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Introduction: Acute febrile illness (AFI), traditionally attributed to malaria, is a common reason for seeking primary healthcare in rural South and Southeast Asia. However, malaria transmission has declined while health workers are often poorly equipped to manage non-malarial AFIs. This results in indiscriminate antibiotic prescribing and care escalation, which promotes antibiotic resistance and may increase healthcare costs. To address this problem, an electronic clinical decision support algorithm (eCDSA) called 'Electronic clinical Decision support for Acute fever Management (EDAM)' has been developed for primary health workers which integrates clinical, epidemiological and vital sign data with simple point-of-care tests to produce a diagnosis and management plan., Methods and Analysis: This is a pragmatic cluster-randomised trial aiming to assess the effect of EDAM and related training on antibiotic prescribing rates in rural Cambodian primary health centres (PHCs) as the primary outcome, along with a range of secondary outcomes including safety. Patients with AFI are eligible for recruitment if they are aged ≥1 year. A cluster is defined as a PHC and PHCs will be randomised to control (standard of care) and intervention (EDAM and associated training) arms, with 15 PHCs per arm. Patients will be followed up after 7 days to ascertain the safety profile of EDAM. Each PHC will recruit 152 patients (total 4560), based on a baseline antibiotic prescription rate of 25% and expected reduction to 17.5% with EDAM., Ethics and Dissemination: Results will be published in international peer-reviewed journals to inform the design of future versions of EDAM and of future trials of similar eCDSAs and other digital health interventions targeted towards rural populations. This study was approved by the Oxford University Tropical Research Ethics Committee (550-23) and the Cambodian National Ethics Committee for Health Research (395-NECHR)., Trial Registration Number: International Standard Randomized Controlled Trial Number Registry (ISRCTN15157105)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

In the Greater Mekong Subregion (GMS), community health workers (CHWs) are a key component of malaria elimination strategies. As malaria declines, support for, and uptake of, malaria services may also subsequently decrease. Expanding their roles beyond malaria has been proposed to sustain the services. A systematic review was conducted to identify and characterize programmes with CHWs providing services in addition to those for malaria in the Asia Pacific. This review describes the expanded roles, identifies evidence of impact or success of the programmes, and explores strategies to ensure sustainability and factors for effective implementation to inform the design of malaria CHW programmes. Searches were conducted in 6 databases, for grey literature, and in bibliographies of retrieved articles. Data were extracted from 38 published articles, 12 programme reports, and 4 programme briefs and analysed using thematic coding and descriptive analysis. Twenty-nine programmes were identified with CHWs performing both malaria and non-malaria roles in the Asia Pacific. There was evidence of impact on malaria incidence in 4 of these, none on malaria mortality, and 4 on other diseases. Monitoring and evaluation mechanisms, multi-sectoral stakeholder collaborations, and adequate training and consistent supervision of CHWs were key to effective programme implementation. Integration of programmes into broader health services, ongoing political and funding support, and engagement with local communities were found to contribute to sustaining provision of health services by CHWs. Expanding CHW roles depends on programme management and strengthening linkages with local health systems. To sustain malaria CHW services, countries need adequate policies and financing, and sufficiently strong health systems to deliver basic health services that are adapted to the health needs of the community which means transitioning away from vertical disease programs. Further research should explore programmes that have not been captured in this review and address gaps in measuring malaria outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Jongdeepaisal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Scrub typhus is underdiagnosed and underreported but emerging as a global public health problem. To inform future burden and prediction studies we examined through a systematic review the potential effect of environmental covariates on scrub typhus occurrence and the methods which have been used for its prediction., Methods: In this systematic review, we searched PubMed, Scopus, Web of Science, China National Knowledge Infrastructure and other databases, with no language and publication time restrictions, for studies that investigated environmental covariates or utilized methods to predict the spatial or temporal human. Data were manually extracted following a set of queries and systematic analysis was conducted., Results: We included 68 articles published in 1978-2024 with relevant data from 7 countries/regions. Significant environmental risk factors for scrub typhus include temperature (showing positive or inverted-U relationships), precipitation (with positive or inverted-U patterns), humidity (exhibiting complex positive, inverted-U, or W-shaped associations), sunshine duration (with positive, inverted-U associations), elevation, the normalized difference vegetation index (NDVI), and the proportion of cropland. Socioeconomic and biological factors were rarely explored. Autoregressive Integrated Moving Average (ARIMA) (n = 8) and ecological niche modelling (ENM) approach (n = 11) were the most popular methods for predicting temporal trends and spatial distribution of scrub typhus, respectively., Conclusions: Our findings summarized the evidence on environmental covariates affecting scrub typhus occurrence and the methodologies used for predictive modelling. We review the existing knowledge gaps and outline recommendations for future studies modelling disease prediction and burden., Trial Registration: PROSPERO CRD42022315209., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Qian Wang reports financial support was provided by Wellcome Trust. Fangyu Ding reports financial support was provided by National Natural Science Foundation of China. Fangyu Ding reports financial support was provided by Chinese Academy of Sciences Youth Innovation Promotion Association. Kartika Saraswati reports financial support was provided by NRF International Partnership Funding Initiative. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

In Thailand, since the 2000s, malaria post (MP) workers have been tasked with promptly detecting and treating all malaria cases to prevent onward transmission in the communities. Expanding their roles to provide health services beyond malaria has been proposed as a strategy to sustain their activities until elimination is reached. This article examines the perspectives of stakeholders on community-based malaria care to assess prospects for expanding the role of MPs. The study incorporated in-depth interviews (IDIs) and focus group discussions (FGDs). In forested communities and local health facilities in northeast Thailand bordering Lao PDR and Cambodia, where malaria transmission is low, IDIs were conducted with 13 MPs and 23 community members. An additional 14 policymakers and implementers across the health sector in Thailand were interviewed. The respondents highlighted how in these border areas population groups most at risk of malaria, namely forest goers and migrants, are reluctant to visit public health facilities. In these areas, MP workers are well integrated in their communities and remain relevant although the communities no longer see malaria as spriority. Common conditions such as dengue, diabetes, insect bites, diarrhea, mental illness and substance abuse, were identified as local health concerns needing potential add-on services from MP workers. Although challenges in terms of training, supervision, and financing were raised, opportunities included additional funds from local administrative offices to maintain and integrate malaria activities with other health programmes. Changes to the roles of MPs should be adapted to changing local needs, some of which were identified in this study, should avoid duplication and potential tensions with other local health programmes, and need to build on the capacity of the community and primary care system. These enabling factors are worthy of consideration by any malaria programmes looking into maintaining their village malaria workers in the Greater Mekong Subregion., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Jongdeepaisal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objectives: Scrub typhus is underdiagnosed and underreported but emerging as a global public health problem. We aimed to provide the first comprehensive review on the seroprevalence, incidence, mortality of and risk factors for scrub typhus., Methods: We searched PubMed, Scopus, Web of Science, China National Knowledge Infrastructure and other databases. Trended incidence and median mortality were calculated and pooled seroprevalence and risk factors for scrub typhus were evaluated using the random-effects meta-analysis., Results: We included 663 articles from 29 countries/regions. The pooled seroprevalence was 10.73% (95%CI 9.47-12.13%) among healthy individuals and 22.58% (95%CI: 20.55%-24.76%) among febrile patients. Mainland China reported the highest number of cases and South Korea and Thailand had the highest incidence rates. Median mortalities were 5.00% (range: 0.00-56.00%) among hospital inpatients, 6.70% (range: 0.00-33.33%) among patients without specified admission status and 2.17% (range: 0.00-22.22%) among outpatients. The significant risk factors included agricultural work, specific vegetation exposure, other outdoor activities, risky personal health habits, and proximity to rodents, livestock, or poultry., Conclusions: Our comprehensive review elucidates the significant yet variable burden of scrub typhus across different regions, underscoring its emergence as a critical public health concern globally., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Malaria Community Health Workers (CHWs) in the Greater Mekong Subregion (GMS) are an important component of malaria elimination efforts. As malaria declines with intensified efforts to eliminate by 2030, expanding their roles beyond malaria could help to sustain funding and provision of malaria services at the community level. Evidence of how programmes have implemented and managed CHWs performing both malaria and non-malaria roles across the Asia-Pacific region can provide insight into the viability of this strategy. A short survey was distributed to national malaria programmes and implementing organizations in the Asia-Pacific region in 2021-2022. The survey identified CHW programmes in the region, and collected information on malaria and non-malarial services provided by CHWs, characteristics of each identified programme, and the impact of COVID-19 on these programmes. 35 survey responses identified 28 programmes in 14 countries. The most frequently reported services provided by malaria CHWs were health promotion and education for malaria (13/14 countries) and other diseases (11/14); and COVID-19 related activities (10/14). Most programmes were financed wholly through donor funding (18/28 programmes), or donor plus government funding (6/28). Of 21 programmes which performed programme evaluation, only 2 evaluated their impacts on diseases beyond malaria. Declining donor funding, and COVID-19 related travel and activity restrictions were identified as implementation challenges. CHWs across the Asia Pacific provide a range of health services with malaria and are resilient under changing public health landscapes such as the COVID-19 pandemic. Further investigation into the impact of additional roles on malaria CHW performance and targeted health outcomes is needed to verify the benefits and feasibility of role expansion. As the GMS approaches elimination, and funding declines, verifying the cost effectiveness of malaria CHW programmes will be vital to persuade donors and countries to invest in malaria CHWs to sustain malaria services, and strengthen community-based health care., Competing Interests: The authors declare that they have no competing interest., (Copyright: © 2024 Jongdeepaisal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Dengue remains a persistent public health concern, especially in tropical and sub-tropical countries like Thailand. The development and utilization of quantitative tools and information technology show significant promise for enhancing public health policy decisions in integrated dengue control. However, the effective implementation of these tools faces multifaceted challenges and barriers that are relatively underexplored., Methods: This qualitative study employed in-depth interviews to gain a better understanding of the experiences and challenges of quantitative tool development and implementation with key stakeholders involved in dengue control in Thailand, using a phenomenological framework. A diverse range of participants, including public health workers and dengue control experts, participated in these interviews. The collected interview data were systematically managed and investigated using thematic analysis to extract meaningful insights., Results: The ability to collect dengue surveillance data and conduct ongoing analyses were contingent upon the availability of individuals possessing essential digital literacy and analytical skills, which were often in short supply. Furthermore, effective space-time early warning and precise data collection were hindered by the absence of user-friendly tools, efficient reporting systems, and complexities in data integration. Additionally, the study underscored the importance of the crucial role of community involvement and collaboration among organizations involved in integrated dengue surveillance, control and quantitative tool development., Conclusions: This study employed a qualitative approach to gain a deeper understanding of the contextual intricacies surrounding the development and implementation of quantitative tools, which, despite their potential for strengthening public health policy decisions in dengue control, remain relatively unexplored in the Thai context. The findings yield valuable insights and recommendations for the development and utilization of quantitative tools to support dengue control in Thailand. This information also has the potential to support use of such tools to exert impact beyond dengue to a broader spectrum of diseases., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Rotejanaprasert et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: In Vietnam, multiple types of community-based malaria workers are recruited to promote access to malaria testing and treatment for at-risk mobile and migrant populations. However, as the country approaches elimination, these roles are at risk from declining investment. This article characterises the different types of workers and relevant health policy in Vietnam, and explores stakeholder perspectives on sustaining and expanding the roles of these workers in the malaria elimination context., Methods: We conducted a rapid policy document review to describe the policy background of community-based health care in Vietnam and identify key informants. In-depth interviews were conducted with policymakers and implementers (n = 11) in different government sectors, international, and civil society organizations. We also conducted interviews (n = 8) and two focus group discussions with community members (n = 12), and interviews with health workers (n = 9) in 18 communities in Phu Yen and Binh Thuan provinces in the central region., Results: Our study identified three main types of malaria workers: village health workers (VHWs), malaria post workers (MPWs) and other groups of workers supported by civil society organisations (CSO). Workers reported being willing to maintain their current roles and potentially provide additional services that respond to community needs, although they were concerned about excess workload and inadequate income. Besides working in a variety of jobs to secure their incomes, mainly in agriculture, VHWs in particular were primarily tasked with supporting the delivery of a wide range of health services from commune health stations. Faced with reduced patients, MPWs and CSO-supported workers could be tasked with the following potential roles: case notification for infectious diseases, real-time data collection and reporting, and screening for non-malaria illnesses using other rapid test kits. There was agreement that the community-based health network is crucial to health care delivery in remote communities and to ensure comprehensive access to care among vulnerable populations. However, policymakers and implementers stressed concerns about their limited skillsets, the inadequate budget to support these workers, and the regulation constraining them from performing diagnosis and treatment activities, highlighting the priority to maintain the capacity of workers and funding allocation through provincial advocacy and multi-programme collaboration., Conclusions: This study highlights the crucial role of community-based health workers in eliminating malaria in Vietnam. Sustained efforts are needed to maintain accessible case detection and treatment while addressing local health concerns beyond malaria. Implementing these strategies requires prioritizing the mapping of groups most in need and developing enablers to raise community awareness and maintain the capacity of these workers. Ensuring political advocacy, financial resources, and coordination between multiple groups are key to maximizing impact and integrating malaria activities into the broader health system., Competing Interests: The authors have declared that no competing interest exist., (Copyright: © 2024 Nguyen et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The government of Lao PDR has increased efforts to control malaria transmission in order to reach its national elimination goal by 2030. Weather can influence malaria transmission dynamics and should be considered when assessing the impact of elimination interventions but this relationship has not been well characterized in Lao PDR. This study examined the space-time association between climate variables and Plasmodium falciparum and Plasmodium vivax malaria incidence from 2010 to 2022., Methods: Spatiotemporal Bayesian modelling was used to investigate the monthly relationship, and model selection criteria were used to evaluate the performance of the models and weather variable specifications. As the malaria control and elimination situation was spatially and temporally dynamic during the study period, the association was examined annually at the provincial level., Results: Malaria incidence decreased from 2010 to 2022 and was concentrated in the southern regions for both P. falciparum and P. vivax. Rainfall and maximum humidity were identified as most strongly associated with malaria during the study period. Rainfall was associated with P. falciparum incidence in the north and central regions during 2010-2011, and with P. vivax incidence in the north and central regions during 2012-2015. Maximum humidity was persistently associated with P. falciparum and P. vivax incidence in the south., Conclusions: Malaria remains prevalent in Lao PDR, particularly in the south, and the relationship with weather varies between regions but was strongest for rainfall and maximum humidity for both species. During peak periods with suitable weather conditions, vector control activities and raising public health awareness on the proper usage of intervention measures, such as indoor residual spraying and personal protection, should be prioritized., (© 2024. The Author(s).)

Background: Thailand aimed to eliminate malaria by 2024, and as such is planning for future prevention of re-establishment in malaria free provinces. Understanding the receptivity of local areas to malaria allows the appropriate targeting of interventions. Current approaches to assessing receptivity involve collecting entomological data. Forest coverage is known to be associated with malaria risk, as an environment conducive to both vector breeding and high-risk human behaviours., Methods: Geolocated, anonymized, individual-level surveillance data from 2011 to 2021 from the Thai Division of Vector-Borne Disease (DVBD) was used to calculate incidence and estimated R c at village level. Forest cover was calculated using raster maps of tree crown cover density and year of forest loss from the publicly available Hansen dataset. Incidence and forest cover were compared graphically and using Spearman's rho. The current foci classification system was applied to data from the last 5 years (2017-2021) and forest cover for 2021 compared between the classifications. A simple risk score was developed to identify villages with high receptivity., Results: There was a non-linear decrease in annual cases by 96.6% (1061 to 36) across the two provinces from 2011 to 2021. Indigenous Annual Parasite Index (API) and approximated R c were higher in villages in highly forested subdistricts, and with higher forest cover within 5 km. Forest cover was also higher in malaria foci which consistently reported malaria cases each year than those which did not. An R c  > 1 was only reported in villages in subdistricts with > 25% forest cover. When applying a simple risk score using forest cover and recent case history, the classifications were comparable to those of the risk stratification system currently used by the DVBD., Conclusions: There was a positive association between forest coverage around a village and indigenous malaria cases. Most local transmission was observed in the heavily forested subdistricts on the international borders with Laos and Cambodia, which are where the most receptive villages are located. These areas are at greater risk of importation of malaria due to population mobility and forest-going activities. Combining forest cover and recent case surveillance data with measures of vulnerability may be useful for prediction of malaria recurrence risk., (© 2024. The Author(s).)

Background: Thailand is approaching local elimination of malaria in the eastern provinces. It has successfully reduced the number of cases over the past decade, but there are persistent transmission hot spots in and around forests. This study aimed to use data from the malaria surveillance system to describe the spatiotemporal trends of malaria in Northeast Thailand and fine-scale patterns in locally transmitted cases between 2011 and 2021., Methods: Case data was stratified based on likely location of infection and parasite species. Annual Parasite Index per 1000 population (API) was calculated for different categories. Time series decomposition was performed to identify trends and seasonal patterns. Statistically significant clusters of high (hot spots) and low (cold spots) API were identified using the Getis-Ord Gi* statistic. The stability of those hot spots and the absolute change in the proportion of API density from baseline were compared by case type., Results: The total number of confirmed cases experienced a non-linear decline by 96.6%, from 1061 in 2011 to 36 in 2021. There has been a decline in both Plasmodium vivax and Plasmodium falciparum case numbers, with only four confirmed P. falciparum cases over the last two years-a 98.89% drop from 180 in 2011. API was generally higher in Si Sa Ket province, which had peaks every 2-3 years. There was a large outbreak in Ubon Ratchathani in 2014-2016 which had a high proportion of P. falciparum reported. The proportion of cases classified increased over the study period, and the proportion of cases classed as indigenous to the village of residence increased from 0.2% to 33.3%. There were stable hot spots of indigenous and imported cases in the south of Si Sa Ket and southeast of Ubon Ratchathani. Plasmodium vivax hot spots were observed into recent years, while those of P. falciparum decreased to zero in Ubon in 2020 and emerged in the eastern part in 2021, the same year that P. falciparum hot spots in Si Sa Ket reached zero., Conclusions: There has been a large, non-linear decline in the number of malaria cases reported and an increasing proportion of cases are classed as indigenous to the patient's village of residence. Stable hot spots of ongoing transmission in the forested border areas were identified, with transmission likely persisting because of remote location and high-risk forest-going behaviours. Future efforts should include cross-border collaboration and continued targeting of high-risk behaviours to reduce the risk of imported cases seeding local transmission., (© 2024. The Author(s).)

Scrub typhus, a vector-borne bacterial infection, is an important but neglected disease globally. Accurately characterizing the burden is challenging because of nonspecific symptoms and limited diagnostics. Prior seroepidemiology studies have struggled to find consensus cutoffs that permit comparisons of estimates across contexts and time. In this study, we present a novel approach that does not require a cutoff and instead uses information about antibody kinetics after infection to estimate seroincidence. We use data from three cohorts of scrub typhus patients in Chiang Rai, Thailand, and Vellore, India, to characterize antibody kinetics after infection and two population serosurveys in the Kathmandu Valley, Nepal, and Tamil Nadu, India, to estimate seroincidence. The samples were tested for IgM and IgG responses to Orientia tsutsugamushi-derived recombinant 56-kDa antigen using commercial enzyme-linked immunosorbent assay kits. We used Bayesian hierarchical models to characterize antibody responses after scrub typhus infection and used the joint distributions of the peak antibody titers and decay rates to estimate population-level incidence rates in the cross-sectional serosurveys. Median responses persisted above an optical density (OD) of 1.8 for 23.6 months for IgG and an OD of 1 for 4.5 months for IgM. Among 18- to 29-year-olds, the seroincidence was 10 per 1,000 person-years (95% CI, 5-19) in Tamil Nadu, India, and 14 per 1,000 person-years (95% CI: 10-20) in the Kathmandu Valley, Nepal. When seroincidence was calculated with antibody decay ignored, the disease burden was underestimated by more than 50%. The approach can be deployed prospectively, coupled with existing serosurveys, or leverage banked samples to efficiently generate scrub typhus seroincidence estimates.

Background: Lao PDR has made significant progress in malaria control. The National Strategic Plans outline ambitious targets, aiming for the elimination of Plasmodium falciparum and P. vivax malaria from all northern provinces by 2025 and national elimination by 2030. This article presents an overview of malaria epidemiology, surveillance, and response systems in Lao PDR, emphasizing experiences and achievements in transmission reduction., Methods: Data on surveillance, monitoring and evaluation systems, human resources, infrastructure, and community malaria knowledge during 2010-2020 were systematically gathered from the national program and relevant documents. The collected information was synthesized, and discussions on challenges and future prospects were provided., Results: Malaria control and elimination activities in Lao PDR were implemented at various levels, with a focus on health facility catchment areas. There has been significant progress in reducing malaria transmission throughout the country. Targeted interventions, such as case management, vector control, and community engagement, using stratification of control interventions by catchment areas have contributed to the decline in malaria cases. In elimination areas, active surveillance strategies, including case and foci investigation, are implemented to identify and stop transmission. The surveillance system has facilitated timely detection and response to malaria cases, enabling these targeted interventions in higher-risk areas., Conclusions: The malaria surveillance and response system in Lao PDR has played a crucial role in reducing transmission and advancing the country towards elimination. Challenges such as importation, drug resistance, and sustaining support require ongoing efforts. Further strengthening surveillance, improving access to services, and addressing transmission determinants are key areas of focus to achieve malaria elimination and enhance population health in Lao PDR., (© 2024. The Author(s).)

Background: Mental illness poses a substantial global public health challenge, including in Thailand, where exploration of access to mental health services is limited. The spatial and temporal dimensions of mental illness in the country are not extensively studied, despite the recognized association between poor mental health and socioeconomic inequalities. Gaining insights into these dimensions is crucial for effective public health interventions and resource allocation., Methods: This retrospective study analyzed mental health service utilization data in Thailand from 2015 to 2023. Temporal trends in annual numbers of individuals visiting mental health services by diagnosis were examined, while spatial pattern analysis employed Moran's I statistics to assess autocorrelation, identify small-area clustering, and hotspots. The implications of our findings for mental health resource allocation and policy were discussed., Results: Between 2015 and 2023, mental health facilities documented a total of 13,793,884 visits. The study found anxiety, schizophrenia, and depression emerged as the top three illnesses for mental health visits, with an increase in patient attendance following the onset of the COVID-19 outbreak. Spatial analysis identified areas of significance for various disorders across different regions of Thailand. Positive correlations between certain disorder pairs were found in specific regions, suggesting shared risk factors or comorbidities., Conclusions: This study highlights spatial and temporal variations in individuals visiting services for different mental disorders in Thailand, shedding light on service gaps and socioeconomic issues. Addressing these disparities requires increased attention to mental health, the development of appropriate interventions, and overcoming barriers to accessibility. The findings provide a baseline for policymakers and stakeholders to allocate resources and implement culturally responsive interventions to improve mental health outcomes., (© 2024. The Author(s).)

Introduction: In low-income and middle-income countries in Southeast Asia, the burden of diseases among rural population remains poorly understood, posing a challenge for effective healthcare prioritisation and resource allocation. Addressing this knowledge gap, the South and Southeast Asia Community-based Trials Network (SEACTN) will undertake a survey that aims to determine the prevalence of a wide range of non-communicable and communicable diseases, as one of the key initiatives of its first project-the Rural Febrile Illness project (RFI). This survey, alongside other RFI studies that explore fever aetiology, leading causes of mortality, and establishing village and health facility maps and profiles, will provide an updated epidemiological background of the rural areas where the network is operational., Methods and Analysis: During 2022-2023, a cross-sectional household survey will be conducted across three SEACTN sites in Bangladesh, Cambodia and Thailand. Using a two-stage cluster-sampling approach, we will employ a probability-proportional-to-size sample method for village, and a simple random sample for household, selection, enrolling all members from the selected households. Approximately 1500 participants will be enrolled per country. Participants will undergo questionnaire interview, physical examination and haemoglobin point-of-care testing. Blood samples will be collected and sent to central laboratories to test for chronic and acute infections, and biomarkers associated with cardiovascular disease, and diabetes. Prevalences will be presented as an overall estimate by country, and stratified and compared across sites and participants' sociodemographic characteristics. Associations between disease status, risk factors and other characteristics will be explored., Ethics and Dissemination: This study protocol has been approved by the Oxford Tropical Research Ethics Committee, National Research Ethics Committee of Bangladesh Medical Research Council, the Cambodian National Ethics Committee for Health Research, the Chiang Rai Provincial Public Health Research Ethical Committee. The results will be disseminated via the local health authorities and partners, peer-reviewed journals and conference presentations., Trial Registration Number: NCT05389540., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)

Background: Dengue is a mosquito-borne disease that causes over 300 million infections worldwide each year with no specific treatment available. Effective surveillance systems are needed for outbreak detection and resource allocation. Spatial cluster detection methods are commonly used, but no general guidance exists on the most appropriate method for dengue surveillance. Therefore, a comprehensive study is needed to assess different methods and provide guidance for dengue surveillance programs., Methods: To evaluate the effectiveness of different cluster detection methods for dengue surveillance, we selected and assessed commonly used methods: Getis Ord [Formula: see text], Local Moran, SaTScan, and Bayesian modeling. We conducted a simulation study to compare their performance in detecting clusters, and applied all methods to a case study of dengue surveillance in Thailand in 2019 to further evaluate their practical utility., Results: In the simulation study, Getis Ord [Formula: see text] and Local Moran had similar performance, with most misdetections occurring at cluster boundaries and isolated hotspots. SaTScan showed better precision but was less effective at detecting inner outliers, although it performed well on large outbreaks. Bayesian convolution modeling had the highest overall precision in the simulation study. In the dengue case study in Thailand, Getis Ord [Formula: see text] and Local Moran missed most disease clusters, while SaTScan was mostly able to detect a large cluster. Bayesian disease mapping seemed to be the most effective, with adaptive detection of irregularly shaped disease anomalies., Conclusions: Bayesian modeling showed to be the most effective method, demonstrating the best accuracy in adaptively identifying irregularly shaped disease anomalies. In contrast, SaTScan excelled in detecting large outbreaks and regular forms. This study provides empirical evidence for the selection of appropriate tools for dengue surveillance in Thailand, with potential applicability to other disease control programs in similar settings., (© 2024. The Author(s).)

Background: Dengue infection ranges from asymptomatic to severe and life-threatening, with no specific treatment available. Vector control is crucial for interrupting its transmission cycle. Accurate estimation of outbreak timing and location is essential for efficient resource allocation. Timely and reliable notification systems are necessary to monitor dengue incidence, including spatial and temporal distributions, to detect outbreaks promptly and implement effective control measures., Methods: We proposed an integrated two-step methodology for real-time spatiotemporal cluster detection, accounting for reporting delays. In the first step, we employed space-time nowcasting modeling to compensate for lags in the reporting system. Subsequently, anomaly detection methods were applied to assess adverse risks. To illustrate the effectiveness of these detection methods, we conducted a case study using weekly dengue surveillance data from Thailand., Results: The developed methodology demonstrated robust surveillance effectiveness. By combining space-time nowcasting modeling and anomaly detection, we achieved enhanced detection capabilities, accounting for reporting delays and identifying clusters of elevated risk in real-time. The case study in Thailand showcased the practical application of our methodology, enabling timely initiation of disease control activities., Conclusion: Our integrated two-step methodology provides a valuable approach for real-time spatiotemporal cluster detection in dengue surveillance. By addressing reporting delays and incorporating anomaly detection, it complements existing surveillance systems and forecasting efforts. Implementing this methodology can facilitate the timely initiation of disease control activities, contributing to more effective prevention and control strategies for dengue in Thailand and potentially other regions facing similar challenges., (© 2024. The Author(s).)

In Southeast Asia malaria elimination is targeted by 2030. Cambodia aims to achieve this by 2025, driven in large part by the urgent need to control the spread of artemisinin-resistant falciparum malaria infections. Rapid elimination depends on sustaining early access to diagnosis and effective treatment. In much of Cambodia, rapid elimination will rely on a village malaria worker (VMW) network. Yet as malaria declines and is no longer a common cause of febrile illness, VMWs may become less popular with febrile patients, as VMWs do not diagnose or treat other conditions at present. There is a risk that VMWs become inactive and malaria rebounds before the complete interruption of transmission is achieved.During 2021-23 a large-scale operational research study was conducted in western Cambodia to explore how a VMW network could be sustained by including health activities that cover non-malarial illnesses to encourage febrile patients to continue to attend. 105 VMWs received new rapid diagnostic tests (including dengue antigen-antibody and combined malaria/C-reactive protein tests), were trained in electronic data collection, and attended health education packages on hygiene and sanitation, disease surveillance and first aid, management of mild illness, and vaccination and antenatal care.In August 2023 the National Malaria Control Programme of Cambodia convened a stakeholder meeting in Battambang, Cambodia. Findings from the study were reviewed in the context of current malaria elimination strategies. The discussions informed policy options to sustain the relevance of the VMW network in Cambodia, and the potential for its integration with other health worker networks. This expansion could ensure VMWs remain active and relevant until malaria elimination is accomplished., (© 2023. The Author(s).)

Introduction: In hospital settings, awareness of, and responsiveness to, COVID-19 are crucial to reducing the risk of transmission among healthcare workers and protecting them from infection. Healthcare professionals can offer insights into the practicalities of infection prevention and control (IPC) measures and on how the guideline aimed to ensure adherence to IPC, including use of personal protective equipment (PPE), could best be delivered during the pandemic. To inform future development of such guideline, this study examined the perspectives of healthcare professionals working in a large hospital during the pandemic regarding their infection risks, the barriers or facilitators to implementing their tasks and the IPC measures to protect their safety and health and of their patients., Method: In-depth interviews were conducted with 23 hospital staff coming into contact with possible or confirmed cases of COVID-19, or were at potential risk of contracting the disease, including medical doctors, nurses, virology laboratory staff, and non-medical workers. This qualitative study was carried out as part of a knowledge, attitudes and practice survey to prevent COVID-19 transmission at Ramathibodi Hospital in Thailand. We used content analysis to categorize and code transcribed interview data. Existing IPC guideline and evidence synthesis of organisational, environmental, and individual factors to IPC adherence among healthcare workers were used to guide the development of the interview questions and analysis., Finding: Factors identified as influencing the use of, and adherence to, prevention measures among healthcare workers included knowledge, perceived risk and concerns about the infection. The extent to which these factors were influential varied based on the medical procedures, among other features, that individuals were assigned to perform in the hospital setting. Beyond availability of PPE and physical safety, ease of and readiness to utilize the equipment and implement IPC measures were crucial to motivate hospital staff to follow the practice guideline. Having a ventilated outdoor space for screening and testing, and interaction through mobile technology, facilitated the performance of healthcare workers while reducing the transmission risk for staff and patients. Adequate training, demonstration of guided practices, and streamlined communications are crucial organisational and management support factors to encourage appropriate use of, and adherence to, implementation of infection prevention and control measures among healthcare workers., Conclusion: This finding could help inform the development of recommendations to optimise compliance with appropriate use of these measures, and to improve guidance to reduce HCW's risk of disease in hospital settings. Further study should explore the perceptions and experiences of health professionals in smaller health facilities and community-based workers during the pandemic, particularly in resource-limited settings., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Jongdeepaisal et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging infectious disease with increasing incidence and geographic extent. The extent to which global climate change affects the incidence of SFTS disease remains obscure. We use an integrated multi-model, multi-scenario framework to assess the impact of global climate change on SFTS disease in China. The spatial distribution of habitat suitability for the tick Haemaphysalis longicornis was predicted by applying a boosted regression tree model under four alternative climate change scenarios (RCP2.6, RCP4.5, RCP6.0, and RCP8.5) for the periods 2030-2039, 2050-2059, and 2080-2089. We incorporate the SFTS cases in the mainland of China from 2010 to 2019 with environmental variables and the projected distribution of H. longicornis into a generalized additive model to explore the current and future spatiotemporal dynamics of SFTS. Our results demonstrate an expanded geographic distribution of H. longicornis toward Northern and Northwestern China, showing a more pronounced change under the RCP8.5 scenario. In contrast, the environmental suitability of H. longicornis is predicted to be reduced in Central and Eastern China. The SFTS incidence in three time periods (2030-2039, 2050-2059, and 2080-2089) is predicted to be increased as compared to the 2010s in the context of various RCPs. A heterogeneous trend across provinces, however, was observed, when an increased incidence in Liaoning and Shandong provinces, while decreased incidence in Henan province is predicted. Notably, we predict possible outbreaks in Xinjiang and Yunnan in the future, where only sporadic cases have been reported previously. These findings highlight the need for tick control and population awareness of SFTS in endemic regions, and enhanced monitoring in potential risk areas., (© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Background: The decline of malaria in Southeast Asia means other causes of fever are increasingly relevant, but often undiagnosed. The objective of this study was to assess the feasibility of point-of-care tests to diagnose acute febrile illnesses in primary care settings., Methods: A mixed-methods study was conducted at nine rural health centres in western Cambodia. Workshops introduced health workers to the STANDARD(TM) Q Dengue Duo, STANDARD(TM) Q Malaria/CRP Duo and a multiplex biosensor detecting antibodies and/or antigens of eight pathogens. Sixteen structured observation checklists assessed users' performances and nine focus group discussions explored their opinions., Results: All three point-of-care tests were performed well under assessment, but sample collection was difficult for the dengue test. Respondents expressed that the diagnostics were useful and could be integrated into routine clinical care, but were not as convenient to perform as standard malaria rapid tests. Health workers recommended that the most valued point-of-care tests would directly inform clinical management (e.g. a decision to refer a patient or to provide/withhold antibiotics)., Conclusions: Deployment of new point-of-care tests to health centres could be feasible and acceptable if they are user-friendly, selected for locally circulating pathogens and are accompanied by disease-specific education and simple management algorithms., (© The Author(s) 2023. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.)

Background: Aedes (Stegomyia)-borne diseases are an expanding global threat, but gaps in surveillance make comprehensive and comparable risk assessments challenging. Geostatistical models combine data from multiple locations and use links with environmental and socioeconomic factors to make predictive risk maps. Here we systematically review past approaches to map risk for different Aedes-borne arboviruses from local to global scales, identifying differences and similarities in the data types, covariates, and modelling approaches used., Methods: We searched on-line databases for predictive risk mapping studies for dengue, Zika, chikungunya, and yellow fever with no geographical or date restrictions. We included studies that needed to parameterise or fit their model to real-world epidemiological data and make predictions to new spatial locations of some measure of population-level risk of viral transmission (e.g. incidence, occurrence, suitability, etc.)., Results: We found a growing number of arbovirus risk mapping studies across all endemic regions and arboviral diseases, with a total of 176 papers published 2002-2022 with the largest increases shortly following major epidemics. Three dominant use cases emerged: (i) global maps to identify limits of transmission, estimate burden and assess impacts of future global change, (ii) regional models used to predict the spread of major epidemics between countries and (iii) national and sub-national models that use local datasets to better understand transmission dynamics to improve outbreak detection and response. Temperature and rainfall were the most popular choice of covariates (included in 50% and 40% of studies respectively) but variables such as human mobility are increasingly being included. Surprisingly, few studies (22%, 31/144) robustly tested combinations of covariates from different domains (e.g. climatic, sociodemographic, ecological, etc.) and only 49% of studies assessed predictive performance via out-of-sample validation procedures., Conclusions: Here we show that approaches to map risk for different arboviruses have diversified in response to changing use cases, epidemiology and data availability. We identify key differences in mapping approaches between different arboviral diseases, discuss future research needs and outline specific recommendations for future arbovirus mapping., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Malaria causes significant morbidity and mortality in tropical and sub-tropical regions, particularly in humanitarian emergencies including refugee camps in malaria endemic areas. An epidemiological investigation was conducted on malaria disease distribution and risk factors in the world's largest refugee settlement, the Rohingya refugee camps on the south-eastern border area of Bangladesh, within 2017-2020., Methods: From February 2017 to March 2020, 30,460 febrile patients were tested for malaria using light microscopy and rapid diagnostic tests. Most were self-presenting symptomatic patients and a minority were from door-to-door malaria screening. Diagnostic tests were done by trained medical technologists upon the advice of the concerned physicians in the camps. Test positivity rate (%) and annual parasite incidence were calculated and compared using chi-squared (χ 2 ) test or odds ratios., Results: The overall average annual test positivity rate (TPR) was 0.05%. TPR was highest in people who had travelled to the forest in the previous 2 months, at 13.60%. Cases were clustered among male adults aged 15-60 years. There were no cases among children under five years or pregnant women and no deaths from malaria., Conclusion: This study found very few malaria cases among Rohingya refugees with the majority of cases being imported from hilly forested areas, which were thus assumed to act as the reservoir for transmission., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Early access to correct diagnosis and appropriate treatment is essential for malaria elimination, and in Cambodia this relies on village malaria workers (VMWs). Decreasing malaria transmission leave VMWs with diminished roles. Activities related to the control of other health conditions could keep these community health workers relevant., Methods: During 2022, 120 VMWs attended training at local health centres on four health education packages: 1. hygiene and sanitation; 2. disease surveillance; 3. management of mild illness; 4. vaccination and antenatal care. All training and evaluation sessions were documented through meeting minutes, and 19 focus group discussions (FGDs) were conducted among VMWs and health centre personnel. Audio-records of FGDs were transcribed and translated in English and underwent thematic analysis., Results: VMWs reported strong interest in the training and welcomed the expansion of their roles thus assuring their continued relevance. VMWs prioritized disease surveillance and management of mild illness among the available training packages because these topics were seen as most relevant. While training was considered comprehensible and important, the low literacy among VMWs was an impediment suggesting training materials need to be delivered visually. Since VMWs have limited resources, incentives could ensure that VMWs are motivated to undertake additional roles and responsibilities., Conclusions: The transformation of VMWs into community health workers with roles beyond malaria is a promising approach for sustaining health care provision in remote areas. Training needs to consider the low scientific literacy, time constraints and limited resources of VMWs., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Betrian et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Malaria transmission in Southeast Asia is increasingly confined to forests, where marginalized groups are exposed primarily through their work. Anti-malarial chemoprophylaxis may help to protect these people. This article examines the effectiveness and practical challenges of engaging forest-goers to participate in a randomized controlled clinical trial of anti-malarial chemoprophylaxis with artemether-lumefantrine (AL) versus a control (multivitamin, MV) for malaria in northeast Cambodia., Methods: The impact of engagement in terms of uptake was assessed as the proportion of people who participated during each stage of the trial: enrolment, compliance with trial procedures, and drug intake. During the trial, staff recorded the details of engagement meetings, including the views and opinions of participants and community representatives, the decision-making processes, and the challenges addressed during implementation., Results: In total, 1613 participants were assessed for eligibility and 1480 (92%) joined the trial, 1242 (84%) completed the trial and received prophylaxis (AL: 82% vs MV: 86%, p = 0.08); 157 (11%) were lost to follow-up (AL: 11% vs MV: 11%, p = 0.79); and 73 (5%) discontinued the drug (AL-7% vs MV-3%, p = 0.005). The AL arm was associated with discontinuation of the study drug (AL: 48/738, 7% vs 25/742, 3%; p = 0.01). Females (31/345, 9%) were more likely (42/1135, 4%) to discontinue taking drugs at some point in the trial (p = 0.005). Those (45/644, 7%) who had no previous history of malaria infection were more likely to discontinue the study drug than those (28/836, 3%) who had a history of malaria (p = 0.02). Engagement with the trial population was demanding because many types of forest work are illegal; and the involvement of an engagement team consisting of representatives from the local administration, health authorities, community leaders and community health workers played a significant role in building trust. Responsiveness to the needs and concerns of the community promoted acceptability and increased confidence in taking prophylaxis among participants. Recruitment of forest-goer volunteers to peer-supervise drug administration resulted in high compliance with drug intake. The development of locally-appropriate tools and messaging for the different linguistic and low-literacy groups was useful to ensure participants understood and adhered to the trial procedures. It was important to consider forest-goers` habits and social characteristics when planning the various trial activities., Conclusions: The comprehensive, participatory engagement strategy mobilized a wide range of stakeholders including study participants, helped build trust, and overcame potential ethical and practical challenges. This locally-adapted approach was highly effective as evidenced by high levels of trial enrolment, compliance with trial procedures and drug intake., (© 2023. The Author(s).)

Dengue is a major public health problem in Myanmar. The country aims to reduce morbidity by 50% and mortality by 90% by 2025 based on 2015 data. To support efforts to reach these goals it is important to have a detailed picture of the epidemiology of dengue, its relationship to meteorological factors and ideally to predict ahead of time numbers of cases to plan resource allocations and control efforts. Health facility-level data on numbers of dengue cases from 2012 to 2017 were obtained from the Vector Borne Disease Control Unit, Department of Public Health, Myanmar. A detailed analysis of routine dengue and dengue hemorrhagic fever (DHF) incidence was conducted to examine the spatial and temporal epidemiology. Incidence was compared to climate data over the same period. Dengue was found to be widespread across the country with an increase in spatial extent over time. The temporal pattern of dengue cases and fatalities was episodic with annual outbreaks and no clear longitudinal trend. There were 127,912 reported cases and 632 deaths from 2012 and 2017 with peaks in 2013, 2015 and 2017. The case fatality rate was around 0.5% throughout. The peak season of dengue cases was from May to August in the wet season but in 2014 peak dengue season continued until November. The strength of correlation of dengue incidence with different climate factors (total rainfall, maximum, mean and minimum temperature and absolute humidity) varied between different States and Regions. Monthly incidence was forecasted 1 month ahead using the Auto Regressive Integrated Moving Average (ARIMA) method at country and subnational levels. With further development and validation, this may be a simple way to quickly generate short-term predictions at subnational scales with sufficient certainty to use for intervention planning., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Zaw et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Human cystic and alveolar echinococcosis are neglected tropical diseases that WHO has prioritized for control in recent years. Both diseases impose substantial burdens on public health and the socio-economy in China. In this study, which is based on the national echinococcosis survey from 2012 to 2016, we aim to describe the spatial prevalence and demographic characteristics of cystic and alveolar echinococcosis infections in humans and assess the impact of environmental, biological and social factors on both types of the disease., Methods: We computed the sex-, age group-, occupation- and education level-specific prevalences of cystic and alveolar echinococcosis at national and sub-national levels. We mapped the geographical distribution of echinococcosis prevalence at the province, city and county levels. Finally, by analyzing the county-level echinococcosis cases combined with a range of associated environmental, biological and social factors, we identified and quantified the potential risk factors for echinococcosis using a generalized linear model., Results: A total of 1,150,723 residents were selected and included in the national echinococcosis survey between 2012 and 2016, of whom 4161 and 1055 tested positive for cystic and alveolar echinococcosis, respectively. Female gender, older age, occupation at herdsman, occupation as religious worker and illiteracy were identified as risk factors for both types of echinococcosis. The prevalence of echinococcosis was found to vary geographically, with areas of high endemicity observed in the Tibetan Plateau region. Cystic echinococcosis prevalence was positively correlated with cattle density, cattle prevalence, dog density, dog prevalence, number of livestock slaughtered, elevation and grass area, and negatively associated with temperature and gross domestic product (GDP). Alveolar echinococcosis prevalence was positively correlated with precipitation, level of awareness, elevation, rodent density and rodent prevalence, and negatively correlated with forest area, temperature and GDP. Our results also implied that drinking water sources are significantly associated with both diseases., Conclusions: The results of this study provide a comprehensive understanding of geographical patterns, demographic characteristics and risk factors of cystic and alveolar echinococcosis in China. This important information will contribute towards developing targeted prevention measures and controlling diseases from the public health perspective., (© 2023. The Author(s).)

Background: Dengue remains a major public health problem in the Philippines, particularly in urban areas of the National Capital Region. Thematic mapping using geographic information systems complemented by spatial analysis such as cluster analysis and hot spot detection can provide useful information to guide preventive measures and control strategies against dengue. Hence, this study was aimed to describe the spatiotemporal distribution of dengue incidence and identify dengue hot spots by barangay using reported cases from Quezon City, the Philippines from 2010 to 2017., Methods: Reported dengue case data at barangay level from January 1, 2010 to December 31, 2017 were obtained from the Quezon City Epidemiology and Surveillance Unit. The annual incidence rate of dengue from 2010 to 2017, expressed as the total number of dengue cases per 10,000 population in each year, was calculated for each barangay. Thematic mapping, global cluster analysis, and hot spot analysis were performed using ArcGIS 10.3.1., Results: The number of reported dengue cases and their spatial distribution varied highly between years. Local clusters were evident during the study period. Eighteen barangays were identified as hot spots., Conclusions: Considering the spatial heterogeneity and instability of hot spots in Quezon City across years, efforts towards the containment of dengue can be made more targeted, and efficient with the application of hot spot analysis in routine surveillance. This may be useful not only for the control of dengue but also for other diseases, and for public health planning, monitoring, and evaluation., (© 2023. The Author(s).)

Background: Malaria outbreaks are important public health concerns that can cause resurgence in endemic regions approaching elimination. We investigated a Plasmodium falciparum outbreak in Attapeu Province, Laos, during the 2020-21 malaria season, using genomic epidemiology methods to elucidate parasite population dynamics and identify its causes., Methods: In this genetic analysis, 2164 P falciparum dried blood spot samples were collected from southern Laos between Jan 1, 2017, and April 1, 2021, which included 249 collected during the Attapeu outbreak between April 1, 2020, and April 1, 2021, by routine surveillance. Genetic barcodes obtained from these samples were used to investigate epidemiological changes underpinning the outbreak, estimate population diversity, and analyse population structure. Whole-genome sequencing data from additional historical samples were used to reconstruct the ancestry of outbreak strains using identity-by-descent analyses., Findings: The outbreak parasite populations were characterised by unprecedented loss of genetic diversity, primarily caused by rapid clonal expansion of a multidrug-resistant strain (LAA1) carrying the kelch13 Arg539Thr (R539T) mutation. LAA1 replaced kelch13 Cys580Tyr (C580Y) mutants resistant to dihydroartemisinin-piperaquine (KEL1/PLA1) as the dominant strain. LAA1 inherited 58·8% of its genome from a strain circulating in Cambodia in 2008. A secondary outbreak strain (LAA2) carried the kelch13 C580Y allele, and a genome that is essentially identical to a Cambodian parasite from 2009. A third, low-frequency strain (LAA7) was a recombinant of KEL1/PLA1 with a kelch13 R539T mutant., Interpretation: These results strongly suggest that the outbreak was driven by a selective sweep, possibly associated with multidrug-resistant phenotypes of the outbreak strains. Established resistant populations can circulate at low frequencies for years before suddenly overwhelming dominant strains when the conditions for selection become favourable-eg, when front-line therapies change. Genetic surveillance can support elimination by characterising key properties of outbreaks such as population diversity, drug resistance marker prevalence, and the origins of outbreak strains., Funding: Bill & Melinda Gates Foundation; The Global Fund to Fight AIDS, Tuberculosis and Malaria; Wellcome Trust., Translation: For the Lao translation of the abstract see Supplementary Materials section., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: To control emerging diseases, governments often have to make decisions based on limited evidence. The effective or temporal reproductive number is used to estimate the expected number of new cases caused by an infectious person in a partially susceptible population. While the temporal dynamic is captured in the temporal reproduction number, the dominant approach is currently based on modeling that implicitly treats people within a population as geographically well mixed., Methods: In this study we aimed to develop a generic and robust methodology for estimating spatiotemporal dynamic measures that can be instantaneously computed for each location and time within a Bayesian model selection and averaging framework. A simulation study was conducted to demonstrate robustness of the method. A case study was provided of a real-world application to COVID-19 national surveillance data in Thailand., Results: Overall, the proposed method allowed for estimation of different scenarios of reproduction numbers in the simulation study. The model selection chose the true serial interval when included in our study whereas model averaging yielded the weighted outcome which could be less accurate than model selection. In the case study of COVID-19 in Thailand, the best model based on model selection and averaging criteria had a similar trend to real data and was consistent with previously published findings in the country., Conclusions: The method yielded robust estimation in several simulated scenarios of force of transmission with computing flexibility and practical benefits. Thus, this development can be suitable and practically useful for surveillance applications especially for newly emerging diseases. As new outbreak waves continue to develop and the risk changes on both local and global scales, our work can facilitate policymaking for timely disease control., (© 2023. The Author(s).)

Background: This report is based on the 2021 annual meeting of the Asia-Pacific Malaria Elimination Network Surveillance and Response Working Group held online on November 1-3, 2021. In light of the 2030 regional malaria elimination goal, there is an urgency for Asia-Pacific countries to accelerate progress towards national elimination and prevent re-establishment. The Asia Pacific Malaria Elimination Network (APMEN) Surveillance Response Working Group (SRWG) supports elimination goals of national malaria control programmes (NMCPs) by expanding the knowledge base, guiding the region-specific operational research agenda and addressing evidence gaps to improve surveillance and response activities., Methods: An online annual meeting was hosted from 1 to 3 November 2021, to reflect on research needed to support malaria elimination in the region, challenges with malaria data quality and integration, current surveillance-related technical tools, and training needs of NMCPs to support surveillance and response activities. Facilitator-led breakout groups were held during meeting sessions to encourage discussion and share experience. A list of identified research priorities was voted on by attendees and non-attending NMCP APMEN contacts., Findings: 127 participants from 13 country partners and 44 partner institutions attended the meeting, identifying strategies to address malaria transmission amongst mobile and migrant populations as the top research priority, followed by cost effective surveillance strategies in low resource settings, and integration of malaria surveillance into broader health systems. Key challenges, solutions and best practices for improving data quality and integrating epidemiology and entomology data were identified, including technical solutions to improve surveillance activities, guiding priority themes for hosting informative webinars, training workshops and technical support initiatives. Inter-regional partnerships and SRWG-led training plans were developed in consultation with members to be launched from 2022 onwards., Conclusion: The 2021 SRWG annual meeting provided an opportunity for regional stakeholders, both NMCPs and APMEN partner institutions, to highlight remaining challenges and barriers and identify research priorities pertaining to surveillance and response in the region, and advocate for strengthening capacity through training and supportive partnerships., (© 2023. The Author(s).)

Background: Microscopic examination is commonly used for malaria diagnosis in the field. However, the lack of well-trained microscopists in malaria-endemic areas impacted the most by the disease is a severe problem. Besides, the examination process is time-consuming and prone to human error. Automated diagnostic systems based on machine learning offer great potential to overcome these problems. This study aims to evaluate Malaria Screener, a smartphone-based application for malaria diagnosis., Methods: A total of 190 patients were recruited at two sites in rural areas near Khartoum, Sudan. The Malaria Screener mobile application was deployed to screen Giemsa-stained blood smears. Both expert microscopy and nested PCR were performed to use as reference standards. First, Malaria Screener was evaluated using the two reference standards. Then, during post-study experiments, the evaluation was repeated for a newly developed algorithm, PlasmodiumVF-Net., Results: Malaria Screener reached 74.1% (95% CI 63.5-83.0) accuracy in detecting Plasmodium falciparum malaria using expert microscopy as the reference after a threshold calibration. It reached 71.8% (95% CI 61.0-81.0) accuracy when compared with PCR. The achieved accuracies meet the WHO Level 3 requirement for parasite detection. The processing time for each smear varies from 5 to 15 min, depending on the concentration of white blood cells (WBCs). In the post-study experiment, Malaria Screener reached 91.8% (95% CI 83.8-96.6) accuracy when patient-level results were calculated with a different method. This accuracy meets the WHO Level 1 requirement for parasite detection. In addition, PlasmodiumVF-Net, a newly developed algorithm, reached 83.1% (95% CI 77.0-88.1) accuracy when compared with expert microscopy and 81.0% (95% CI 74.6-86.3) accuracy when compared with PCR, reaching the WHO Level 2 requirement for detecting both Plasmodium falciparum and Plasmodium vivax malaria, without using the testing sites data for training or calibration. Results reported for both Malaria Screener and PlasmodiumVF-Net used thick smears for diagnosis. In this paper, both systems were not assessed in species identification and parasite counting, which are still under development., Conclusion: Malaria Screener showed the potential to be deployed in resource-limited areas to facilitate routine malaria screening. It is the first smartphone-based system for malaria diagnosis evaluated on the patient-level in a natural field environment. Thus, the results in the field reported here can serve as a reference for future studies., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network.  It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented.  For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations.  We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent.  We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines.  Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website., Competing Interests: No competing interests were disclosed., (Copyright: © 2023 MalariaGEN et al.)

Background: Malaria in the eastern Greater Mekong subregion has declined to historic lows. Countries in the Greater Mekong subregion are accelerating malaria elimination in the context of increasing antimalarial drug resistance. Infections are now increasingly concentrated in remote, forested foci. No intervention has yet shown satisfactory efficacy against forest-acquired malaria. The aim of this study was to assess the efficacy of malaria chemoprophylaxis among forest goers in Cambodia., Methods: We conducted an open-label, individually randomised controlled trial in Cambodia, which recruited participants aged 16-65 years staying overnight in forests. Participants were randomly allocated 1:1 to antimalarial chemoprophylaxis, a 3-day course of twice-daily artemether-lumefantrine followed by the same daily dosing once a week while travelling in the forest and for a further 4 weeks after leaving the forest (four tablets per dose; 20 mg of artemether and 120 mg of lumefantrine per tablet), or a multivitamin with no antimalarial activity. Allocations were done according to a computer-generated randomisation schedule, and randomisation was in permuted blocks of size ten and stratified by village. Investigators and participants were not masked to drug allocation, but laboratory investigations were done without knowledge of allocation. The primary outcome was a composite endpoint of either clinical malaria with any Plasmodium species within 1-28, 29-56, or 57-84 days, or subclinical infection detected by PCR on days 28, 56, or 84 using complete-case analysis of the intention-to-treat population. Adherence to study drug was assessed primarily by self-reporting during follow-up visits. Adverse events were assessed in the intention-to-treat population as a secondary endpoint from self-reporting at any time, plus a physical examination and symptom questionnaire at follow-up. This trial is registered at ClinicalTrials.gov (NCT04041973) and is complete., Findings: Between March 11 and Nov 20, 2020, 1480 individuals were enrolled, of whom 738 were randomly assigned to artemether-lumefantrine and 742 to the multivitamin. 713 participants in the artemether-lumefantrine group and 714 in the multivitamin group had a PCR result or confirmed clinical malaria by rapid diagnostic test during follow-up. During follow-up, 19 (3%, 95% CI 2-4) of 713 participants had parasitaemia or clinical malaria in the artemether-lumefantrine group and 123 (17%, 15-20) of 714 in the multivitamin group (absolute risk difference 15%, 95% CI 12-18; p<0·0001). During follow-up, there were 166 malaria episodes caused by Plasmodium vivax, 14 by Plasmodium falciparum, and five with other or mixed species infections. The numbers of participants with P vivax were 18 (3%, 95% CI 2-4) in the artemether-lumefantrine group versus 112 (16%, 13-19) in the multivitamin group (absolute risk difference 13%, 95% CI 10-16; p<0·0001). The numbers of participants with P falciparum were two (0·3%, 95% CI 0·03-1·01) in the artemether-lumefantrine group versus 12 (1·7%, 0·9-2·9) in the multivitamin group (absolute risk difference 1·4%, 95% CI 0·4-2·4; p=0·013). Overall reported adherence to the full course of medication was 97% (95% CI 96-98; 1797 completed courses out of 1854 courses started) in the artemether-lumefantrine group and 98% (97-98; 1842 completed courses in 1885 courses started) in the multivitamin group. Overall prevalence of adverse events was 1·9% (355 events in 18 806 doses) in the artemether-lumefantrine group and 1·1% (207 events in 19 132 doses) in the multivitamin group (p<0·0001)., Interpretation: Antimalarial chemoprophylaxis with artemether-lumefantrine was acceptable and well tolerated and substantially reduced the risk of malaria. Malaria chemoprophylaxis among high-risk groups such as forest workers could be a valuable tool for accelerating elimination in the Greater Mekong subregion., Funding: The Global Fund to Fight AIDS, Tuberculosis and Malaria; Wellcome Trust., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Scrub typhus is a climate-sensitive and life-threatening vector-borne disease that poses a growing public health threat. Although the climate-epidemic associations of many vector-borne diseases have been studied for decades, the impacts of climate on scrub typhus remain poorly understood, especially in the context of global warming. Here we incorporate Chinese national surveillance data on scrub typhus from 2010 to 2019 into a climate-driven generalized additive mixed model to explain the spatiotemporal dynamics of this disease and predict how it may be affected by climate change under various representative concentration pathways (RCPs) for three future time periods (the 2030s, 2050s, and 2080s). Our results demonstrate that temperature, precipitation, and relative humidity play key roles in driving the seasonal epidemic of scrub typhus in mainland China with a 2-month lag. Our findings show that the change of projected spatiotemporal dynamics of scrub typhus will be heterogeneous and will depend on specific combinations of regional climate conditions in future climate scenarios. Our results contribute to a better understanding of spatiotemporal dynamics of scrub typhus, which can help public health authorities refine their prevention and control measures to reduce the risks resulting from climate change., (© 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Objective: Antimalarial chemoprophylaxis for high risk groups in endemic areas of Southeast Asia has the potential to reduce malaria transmission and accelerate elimination. However, the optimal choice of medication and dosing for many potential candidates is not clear. For a planned randomised controlled trial of prophylaxis for forest goers in Cambodia, artemether-lumefantrine (AL) was selected because of its ongoing efficacy and excellent tolerability and safety. As AL had not been used before for this purpose, a previously published pooled pharmacometric meta-model was used to determine the optimal dosing schedule., Results: A full 3 day AL treatment course given twice a month, and twice daily treatment given once a week, resulted in trough concentrations consistently above the therapeutic threshold of 200 ng/mL. However, the most favourable exposure profile, and arguably most practical dosing scenario, was an initial 3 day full AL treatment course followed by twice daily dosing given once a week for the duration of chemoprevention. The latter was adopted as the dosing schedule for the trial., (© 2022. The Author(s).)

Background: Independent emergence and spread of artemisinin-resistant Plasmodium falciparum malaria have recently been confirmed in Africa, with molecular markers associated with artemisinin resistance increasingly detected. Surveillance to promptly detect and effectively respond to anti-malarial resistance is generally suboptimal in Africa, especially in low transmission settings where therapeutic efficacy studies are often not feasible due to recruitment challenges. However, these communities may be at higher risk of anti-malarial resistance., Methods: From March 2018 to February 2020, a sequential mixed-methods study was conducted to evaluate the feasibility of the near-real-time linkage of individual patient anti-malarial resistance profiles with their case notifications and treatment response reports, and map these to fine scales in Nkomazi sub-district, Mpumalanga, a pre-elimination area in South Africa., Results: Plasmodium falciparum molecular marker resistance profiles were linked to 55.1% (2636/4787) of notified malaria cases, 85% (2240/2636) of which were mapped to healthcare facility, ward and locality levels. Over time, linkage of individual malaria case demographic and molecular data increased to 75.1%. No artemisinin resistant validated/associated  Kelch-13 mutations were detected in the 2385 PCR positive samples. Almost all 2812 samples assessed for lumefantrine susceptibility carried the wildtype mdr86ASN and crt76LYS alleles, potentially associated with decreased lumefantrine susceptibility., Conclusion: Routine near-real-time mapping of molecular markers associated with anti-malarial drug resistance on a fine spatial scale provides a rapid and efficient early warning system for emerging resistance. The lessons learnt here could inform scale-up to provincial, national and regional malaria elimination programmes, and may be relevant for other antimicrobial resistance surveillance., (© 2022. The Author(s).)

Background: The collection and utilization of surveillance data is essential in monitoring progress towards achieving malaria elimination, in the timely response to increases in malaria case numbers and in the assessment of programme functioning. This paper describes the surveillance activities used by the malaria elimination task force (METF) programme which operates in eastern Myanmar, and provides an analysis of data collected from weekly surveillance, case investigations, and monitoring and evaluation of programme performance., Methods: This retrospective analysis was conducted using data collected from a network of 1250 malaria posts operational between 2014 and 2021. To investigate changes in data completeness, malaria post performance, malaria case numbers, and the demographic details of malaria cases, summary statistics were used to compare data collected over space and time., Results: In the first 3 years of the METF programme, improvements in data transmission routes resulted in a 18.9% reduction in late reporting, allowing for near real-time analysis of data collected at the malaria posts. In 2020, travel restrictions were in place across Karen State in response to COVID-19, and from February 2021 the military coup in Myanmar resulted in widescale population displacement. However, over that period there has been no decline in malaria post attendance, and the majority of consultations continue to occur within 48 h of fever onset. Case investigations found that 43.8% of cases travelled away from their resident village in the 3 weeks prior to diagnosis and 36.3% reported never using a bed net whilst sleeping in their resident village, which increased to 72.2% when sleeping away from their resident village. Malaria post assessments performed in 82.3% of the METF malaria posts found malaria posts generally performed to a high standard., Conclusions: Surveillance data collected by the METF programme demonstrate that despite significant changes in the context in which the programme operates, malaria posts have remained accessible and continue to provide early diagnosis and treatment contributing to an 89.3% decrease in Plasmodium falciparum incidence between 2014 and 2021., (© 2022. The Author(s).)

To conduct a multi-center prospective study over more than one year requires an efficient system that can synchronize collection of data from several sources in real-time and facilitate remote data management. This paper describes the design and use of an in-house data collection and sample information management system that was used in a prospective birth cohort study in Thailand. Participants were enrolled from three hospitals and were required to visit their respective hospital and complete self-administered questionnaires (SAQ) at every visit. The in-house informatics system required integration of the data collection streams that can handle three different types of data (SAQ, clinical record, and laboratory sample tracking). The system has been implemented in the pilot phase of a birth cohort study and has demonstrated its usability for further application to an expanded study.

Background: Late treatment failures after artemisinin-based combination therapies (ACTs) for falciparum malaria have increased in the Greater Mekong subregion in southeast Asia. Addition of amodiaquine to artemether-lumefantrine could provide an efficacious treatment for multidrug-resistant infections., Methods: We conducted an open-label, randomised trial at five hospitals or health centres in three locations (western Cambodia, eastern Cambodia, and Vietnam). Eligible participants were male and female patients aged 2-65 years with uncomplicated Plasmodium falciparum malaria. Patients were randomly allocated (1:1 in blocks of eight to 12) to either artemether-lumefantrine alone (dosed according to WHO guidelines) or artemether-lumefantrine plus amodiaquine (10 mg base per kg/day), both given orally as six doses over 3 days. All received a single dose of primaquine (0·25 mg/kg) 24 h after the start of study treatment to limit transmission of the parasite. Parasites were genotyped, identifying artemisinin resistance. The primary outcome was Kaplan-Meier 42-day PCR-corrected efficacy against recrudescence of the original parasite, assessed by intent-to-treat. Safety was a secondary outcome. This completed trial is registered at ClinicalTrials.gov (NCT03355664)., Findings: Between March 18, 2018, and Jan 30, 2020, 310 patients received randomly allocated treatment; 154 received artemether-lumefantrine alone and 156 received artemether-lumefantrine plus amodiaquine. Parasites from 305 of these patients were genotyped. 42-day PCR-corrected treatment efficacy was noted in 151 (97%, 95% CI 92-99) of 156 patients with artemether-lumefantrine plus amodiaquine versus 146 (95%, 89-97) of 154 patients with artemether-lumefantrine alone; hazard ratio (HR) for recrudescence 0·6 (95% CI 0·2-1·9, p=0·38). Of the 13 recrudescences, 12 were in 174 (57%) of 305 infections with pfkelch13 mutations indicating artemisinin resistance, for which 42-day efficacy was noted in 89 (96%) of 93 infections with artemether-lumefantrine plus amodiaquine versus 73 (90%) of 81 infections with artemether-lumefantrine alone; HR for recrudescence 0·44 (95% CI 0·14-1·40, p=0·17). Artemether-lumefantrine plus amodiaquine was generally well tolerated, but the number of mild (grade 1-2) adverse events, mainly gastrointestinal, was greater in this group compared with artemether-lumefantrine alone (vomiting, 12 [8%] with artemether-lumefantrine plus amodiaquine vs three [2%] with artemether-lumefantrine alone, p=0·03; and nausea, 11 [7%] with artemether-lumefantrine plus amodiaquine vs three [2%] with artemether-lumefantrine alone, p=0·05). Early vomiting within 1 h of treatment, requiring retreatment, occurred in no patients of 154 with artemether-lumefantrine alone versus five (3%) of 156 with artemether-lumefantrine plus amodiaquine, p=0·06. Bradycardia (≤54 beats/min) of any grade was noted in 59 (38%) of 154 patients with artemether-lumefantrine alone and 95 (61%) of 156 with artemether-lumefantrine plus amodiaquine, p=0·0001., Interpretation: Artemether-lumefantrine plus amodiaquine provides an alternative to artemether-lumefantrine alone as first-line treatment for multidrug-resistant P falciparum malaria in the Greater Mekong subregion, and could prolong the therapeutic lifetime of artemether-lumefantrine in malaria-endemic populations., Funding: Bill & Melinda Gates Foundation, Wellcome Trust., Competing Interests: Declaration of interests The Mahidol Oxford Research Unit (MORU) has received funding for other studies of antimalarial treatment from Fosun Pharmaceuticals, which manufactures artemisinin combination therapies. We declare no other competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Tuberculosis is a leading cause of infectious disease globally, especially in developing countries. Better knowledge of spatial and temporal patterns of tuberculosis burden is important for effective control programs as well as informing resource and budget allocation. Studies have demonstrated that TB exhibits highly complex dynamics in both spatial and temporal dimensions at different levels. In Thailand, TB research has been primarily focused on surveys and clinical aspects of the disease burden with little attention on spatiotemporal heterogeneity. This study aimed to describe temporal trends and spatial patterns of TB incidence and mortality in Thailand from 2011 to 2020. Monthly TB case and death notification data were aggregated at the provincial level. Age-standardized incidence and mortality were calculated; time series and global and local clustering analyses were performed for the whole country. There was an overall decreasing trend with seasonal peaks in the winter. There was spatial heterogeneity with disease clusters in many regions, especially along international borders, suggesting that population movement and socioeconomic variables might affect the spatiotemporal distribution in Thailand. Understanding the space-time distribution of TB is useful for planning targeted disease control program activities. This is particularly important in low- and middle-income countries including Thailand to help prioritize allocation of limited resources.

In rural areas of South and Southeast Asia malaria is declining but febrile illnesses still account for substantial morbidity and mortality. Village health workers (VHWs) are often the first point of contact with the formal health system, and for patients with febrile illnesses they can provide early diagnosis and treatment of malaria. However, for the majority of febrile patients, VHWs lack the training, support and resources to provide further care. Consequently, treatable bacterial illnesses are missed, antibiotics are overused and poorly targeted, and patient attendance wanes along with declining malaria. This Open Letter announces the start of a new initiative, the Rural Febrile Illness (RFI) project, the first in a series of projects to be implemented as part of the South and Southeast Asian Community-based Trials Network (SEACTN) research programme. This multi-country, multi-site project will run in Bangladesh, Cambodia, Lao PDR, Thailand, and Myanmar. It will define the epidemiological baseline of febrile illness in nine remote and underserved areas of Asia where malaria endemicity is declining and access to health services is limited. The RFI project aims to determine the incidence, causes and outcomes of febrile illness; understand the opportunities, barriers and appetite for adjustment of the role of VHWs to include management of non-malarial febrile illnesses; and establish a network of community healthcare providers and facilities capable of implementing interventions designed to triage, diagnose and treat patients presenting with febrile illnesses within these communities in the future., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Chandna A et al.)

Background: The increase in artemisinin resistance threatens malaria elimination in Asia by the target date of 2030 and could derail control efforts in other endemic regions. This study aimed to develop up-to-date spatial distribution visualisations of the kelch13 ( K13 ) gene markers of artemisinin resistance in Plasmodium falciparum for policy makers., Methods: In this systematic review and spatiotemporal analysis we used the WorldWide Antimalarial Resistance Network (WWARN) surveyor molecular markers of artemisinin resistance database. We updated the database by searching PubMed and SCOPUS for studies published between Jan 1, 1990, and March 31, 2021. Articles were included if they contained data on K13 markers of artemisinin resistance from patients' samples in Asia and articles already included in the WWARN database were excluded. Data were extracted from the published articles and authors were contacted when information was missing. We used the lowest administrative unit levels for the sampling locations of all the K13 data to describe the spatiotemporal distribution. The numbers of samples tested and those with each molecular marker in each administrative unit level were aggregated by year to calculate the marker prevalence over time., Findings: Data were collated from 72 studies comprising K13 markers from 16 613 blood samples collected from 1991 to 2020 from 18 countries. Most samples were from Myanmar (3842 [23·1%]), Cambodia (3804 [22·9%]), and Vietnam (2663 [16·0%]). The median time between data collection and publication was 3·6 years (range 0·9-25·0, IQR 2·7 [2·5-5·2]). There was a steady increase in the prevalence of WHO-validated K13 markers, with the lowest of 4·3% in 2005 (n=47) and the highest of 62·9% in 2018 (n=264). Overall, the prevalence of Cys580Tyr mutation increased from 48·9% in 2002 to 84·9% in 2018., Interpretation: From 2002 to 2018, there has been a steady increase in geographical locations and the proportion of infected people with validated artemisinin resistance markers. More consistent data collection, over more extended periods in the same areas with the rapid sharing of data are needed to map the spread and evolution of resistance to better inform policy decisions. Data in the literature are reported in a heterogeneous way leading to difficulties in pooling and interpretation. We propose here a tool with a set of minimum criteria for reporting future studies., Funding: This research was funded in part by the Wellcome Trust., Competing Interests: We declare no competing interests., (© 2022 Elsevier Ltd. All rights reserved. This is an Open Access article under the CC BY 4.0 license.)

Background: Across the Greater Mekong Subregion, malaria remains a dangerous infectious disease, particularly for people who visit forested areas where residual transmission continues. Because vector control measures offer incomplete protection to forest goers, chemoprophylaxis has been suggested as a potential supplementary measure for malaria prevention and control. To implement prophylaxis effectively, additional information is needed to understand forest goers' activities and their willingness to use malaria prevention measures, including prophylaxis, and how it could be delivered in communities. Drawing on in-depth interviews with forest goers and stakeholders, this article examines the potential acceptability and implementation challenges of malaria prophylaxis for forest goers in northeast Thailand., Methods: In-depth interviews were conducted with forest goers (n = 11) and stakeholders (n = 16) including healthcare workers, community leaders, and policymakers. Interviews were audio-recorded, transcribed and coded using NVivo, employing an inductive and deductive approach, for thematic analysis., Results: Forest goers were well aware of their (elevated) malaria risk and reported seeking care for malaria from local health care providers. Forest goers and community members have a close relationship with the forest but are not a homogenous group: their place and time-at-risk varied according to their activities and length of stay in the forest. Among stakeholders, the choice and cost of anti-malarial prophylactic regimen-its efficacy, length and complexity, number of tablets, potential side effects, and long-term impact on users-were key considerations for its feasibility. They also expressed concern about adherence to the preventive therapy and potential difficulty treating malaria patients with the same regimen. Prophylaxis was considered a low priority in areas with perceived accessible health system and approaching malaria elimination., Conclusions: In the context of multi-drug resistance, there are several considerations for implementing malaria prophylaxis: the need to target forest goers who are at-risk with a clear period of exposure, to ensure continued use of vector control measures and adherence to prophylactic anti-malarials, and to adopt an evidence-based approach to determine an appropriate regimen. Beyond addressing current intervention challenges and managing malaria incidence in low-transmission setting, it is crucial to keep malaria services available and accessible at the village level especially in areas home to highly mobile populations., (© 2022. The Author(s).)

Background: Despite significant decline in malarial incidence and mortality in countries across the Greater Mekong Subregion, the disease remains a public health challenge in the region; transmission continues mainly among people who visit forests in remote areas, often along international borders, where access to primary healthcare is limited. In the absence of effective vector-control measures and limited exposure periods, malaria chemoprophylaxis has been proposed as a strategy to protect forest goers. As a rarely used approach for indigenous populations, questions remain about its feasibility and acceptability. Drawing on in-depth interviews with forest goers and stakeholders, this article examines opportunities and challenges for implementation of anti-malarial chemoprophylaxis for forest goers in Lao PDR., Methods: In-depth interviews were conducted with 16 forest goers and 15 stakeholders in Savannakhet province, Lao PDR. Interview topics included experience of malaria prevention and health services, and perceptions of prophylaxis as a potential component of malaria elimination strategy. The interviews were transcribed and coded using inductive and deductive approaches for qualitative thematic analysis., Results: In ethnically and geographically diverse villages, awareness of malaria risk prompts forest goers to protect themselves, albeit sub-optimally using available preventive measures. Stakeholders highlighted challenges for targeting at-risk populations and approaches to address forest malaria in southern Lao PDR. Among policymakers, choice and cost of anti-malarials, particularly their efficacy and source of funding, were key considerations for the feasibility of malaria prophylaxis. Acceptability of prophylaxis among forest goers was also influenced by the complexity of the regimen, including the number of tablets and timing of doses. Implementation of prophylaxis may be affected by a lack of transportation and communication barriers in remote communities., Conclusion: Adding prophylaxis to existing malaria control activities requires strengthening the capacity of local health workers in Lao PDR. Ideally, this would be part of an integrated approach that includes strategies to address the other febrile illnesses that forest goers describe as priority health concerns. The prophylactic regimen also requires careful consideration in terms of effectiveness and simplicity of dosing., (© 2021. The Author(s).)