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Background: People living with human immunodeficiency virus (HIV) and comorbid diabetes mellitus (DM) face significant challenges owing to the complex interplay between these chronic conditions and the need for comprehensive and integrated care. Service availability and readiness for primary care are essential for the health of individuals and populations. Aim: This study aimed to explore barriers and facilitators to the provision of care to the patients with HIV and T2DM comorbidity. Setting: The study was conducted at Primary health centres in Harare, Zimbabwe. Methods: A mixed-methods design was applied. Results: An audit of primary care facilities identified that there was adequate infrastructure and equipment for HIV and T2DM diagnosis and treatment. However, there are gaps in the availability of essential medicines and supplies, such as test strips for blood glucose monitoring. The assessment also showed that the centres had a chronic shortage of healthcare providers, including doctors, nurses and counsellors, and there was a need for additional training and support for healthcare providers in the management of HIV and T2DM. Conclusion: The study concludes that the delivery of health services to patients with HIV and T2DM at primary care centres in Harare, Zimbabwe, faces significant challenges. Suggestions included improved resource allocation and multisectoral collaboration to improve the delivery of healthcare services. Contribution: The research contributes insight into disparities between urban and rural primary care facilities in providing services, emphasizing the need for targeted interventions to bridge gaps and enhance care quality.

Abstract Background Snail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for effective control. Given the dearth of knowledge on African trematodes, this study aimed to map snail and trematode diversity, focusing on (i) characterizing gastropod snail species and their trematode parasites, (ii) determining infection rates of snail species as intermediate hosts for medically, veterinary, and ecologically significant trematodes, and (iii) comparing their diversity across endemic regions. Methods A cross-sectional study conducted in 2021 in Chiredzi and Wedza districts in Zimbabwe, known for high human schistosomiasis prevalence, involved malacological surveys at 56 sites. Trematode infections in snails were detected through shedding experiments and multiplex rapid diagnostic polymerase chain reactions (RD-PCRs). Morphological and molecular analyses were employed to identify snail and trematode species. Results Among 3209 collected snail specimens, 11 species were identified, including schistosome and fasciolid competent snail species. We report for the first time the invasive exotic snail Tarebia granifera in Zimbabwe, which was highly abundant, mainly in Chiredzi, occurring at 29 out of 35 sites. Shedding experiments on 1303 snails revealed a 2.24% infection rate, with 15 trematode species identified through molecular genotyping. Five species were exclusive to Chiredzi: Bolbophorus sp., Schistosoma mansoni, Schistosoma mattheei, Calicophoron sp., and Uvulifer sp. Eight were exclusive to Wedza, including Trichobilharzia sp., Stephanoprora amurensis, Spirorchid sp., and Echinostoma sp. as well as an unidentified species of the Plagiorchioidea superfamily. One species, Tylodelphys mashonensis, was common to both regions. The RD-PCR screening of 976 non-shedding snails indicated a 35.7% trematode infection rate, including the presence of schistosomes (1.1%) Fasciola nyanzae (0.6%). In Chiredzi, Radix natalensis had the highest trematode infection prevalence (33.3%), while in Wedza, R. natalensis (55.4%) and Bulinus tropicus (53.2%) had the highest infection prevalence. Conclusions Our xenomonitoring approach unveiled 15 trematode species, including nine new records in Zimbabwe. Schistosoma mansoni persists in the study region despite six mass deworming rounds. The high snail and parasite diversity, including the presence of exotic snail species that can impact endemic species and biomedically important trematodes, underscores the need for increased monitoring. Graphical Abstract

Abstract Background Highly active antiretroviral therapy (HAART) has improved the life expectancy of people living with HIV (PLWH) and has increased the risk of chronic non-communicable diseases. Comorbid HIV and diabetes mellitus (DM) significantly increase cardiovascular disease and mortality risk. This study aimed to determine the prevalence of type 2 diabetes mellitus among HIV-positive patients receiving HAART in Zimbabwe and its associated risk factors. Methods This cross-sectional study was conducted at eight primary healthcare facilities in Harare, Zimbabwe, between January 2022 and March 2023. Non-probability convenience sampling was used to recruit adult HIV-positive patients undergoing HAART attending the facilities. Data were captured on clinical history and socio-demographic and behavioral characteristics, and analyzed using descriptive statistics to determine DM prevalence rates. Additionally, bivariate and multivariate logistic regression models were employed to examine factors associated with HIV and DM comorbidities. Results A total of 450 participants were included in this study, of which 57.6% (n = 259) were female. The majority were married (73.8%) and older than 35 years (80.2%). Most participants had completed high school (87.6%) and 68.9% were employed either formally or self-employed. The prevalence of diabetes mellitus (DM) was 14.9%. HIV/DM comorbidity was more prevalent in patients who were female, self-employed, and smoked (p 30 kg/m2), smoking, and alcohol consumption were associated with an increased risk of DM. Regular physical activity is associated with a reduced risk of DM. Conclusion A substantial burden of DM was found in PLWH. The intersectoral integration approach is advocated, and active screening for DM is recommended. Gender-specific interventions are necessary to target diseases and health behaviors that differ between men and women. These interventions should be customized to the specific diseases and behaviors of each group.

Abstract Climate change is predicted to disproportionately impact sub‐Saharan Africa, with potential devastating consequences on plant populations. Climate change may, however, impact intraspecific taxa differently. The aim of the study was to determine the current distribution and impact of climate change on three varieties of Vachellia sieberiana, that is, var. sieberiana, var. villosa and var. woodii. Ensemble species distribution models (SDMs) were built in “biomod2” using 66, 45, and 137 occurrence records for var. sieberiana, var. villosa, and var. woodii, respectively. The ensemble SDMs were projected to 2041–2060 and 2081–2100 under three general circulation models (GCMs) and two shared socioeconomic pathways (SSPs). The three GCMs were the Canadian Earth System Model version 5, the Institut Pierre‐Simon Laplace Climate Model version 6A Low Resolution, and the Model for Interdisciplinary Research on Climate version 6. The suitable habitat of var. sieberiana predominantly occurs in the Sudanian and Zambezian phytochoria while that of var. villosa largely occurs in the Sudanian phytochorion. The suitable habitat of var. woodii mainly occurs in the Zambezian phyotochorion. There is coexistence of var. villosa and var. sieberiana in the Sudanian phytochorion while var. sieberiana and var. woodii coexist in the Zambezian phytochorion. Under SSP2‐4.5 in 2041–2060 and averaged across the three GCMs, the suitable habitat expanded by 33.8% and 119.7% for var. sieberiana and var. villosa, respectively. In contrast, the suitable habitat of var. woodii contracted by −8.4%. Similar trends were observed in 2041–2060 under SSP5‐8.5 [var. sieberiana (38.6%), var. villosa (139.0%), and var. woodii (−10.4%)], in 2081–2100 under SSP2‐4.5 [var. sieberiana (4.6%), var. villosa (153.4%), and var. woodii (−14.4%)], and in 2081–2100 under SSP5‐8.5 [var. sieberiana (49.3%), var. villosa (233.4%), and var. woodii (−30.7%)]. Different responses to climate change call for unique management and conservation decisions for the varieties.

BackgroundIntegrated health care is an approach characterized by a high degree of collaboration and communication among health professionals. Integration of HIV/NCD is recommended to enhance the quality of healthcare services being provided. Duplication of limited resources is minimized, and a holistic care approach is promoted by shifting from acute and reactive care to care that embraces patient-centredness that includes promotive health and disease surveillance. The high burden of HIV disease in sub-Saharan Africa (SSA) combined with the increasing prevalence of chronic non-communicable diseases (NCDs) necessitates a review of how health systems has been doing to deliver quality integrated care for people living with HIV (PLWH) and comorbid chronic NCDs.MethodsA scoping review was conducted to identify and describe all publications on integrated chronic care management models at the primary care level in the SSA context, particularly those that addressed the care of PLHIV with co-morbid chronic NCDs. The inclusion and exclusion criteria were applied, and duplicates were removed.ResultsA total of twenty-one articles were included in the final review. Integrated healthcare systems were reported in only eight SSA countries-(South Africa, Uganda, Kenya, the United Republic of Tanzania, Zambia, Malawi, Zimbabwe and Swaziland). Integrated care systems adopted one of three health models. These included added-on NCD services to previously dedicated HIV care facilities, expansion of primary care facilities to include HIV care and establishment of integrated care services. Short-term benefits included staff capacitation, improved retention of patients and improved screening and detection of NCDs. However, the expansion of existing services resulted in an increased workload with no additional staff. A significant positive change noted by communities was that there was less or no stigmatisation of people living with HIV when attending dedicated HIV clinics.ConclusionEvidence of integrated healthcare services for PLWH and co-morbid of NCDs in SSA is scanty. Data on some short-term benefits of integrated care was available, but evidence was absent on the long-term outcomes. Randomized clinical trials with clearly defined comparator groups and standardized measures of HIV and NCD outcomes are needed to demonstrate non-inferiority of integrated against non-integrated care.

Abstract The spatial and seasonal distribution, abundance, and infection rates of human schistosomiasis intermediate host snails and interactions with other freshwater snails, water physicochemical parameters, and climatic factors was determined in this study. A longitudinal malacology survey was conducted at seventy-nine sites in seven districts in KwaZulu-Natal province between September 2020 and August 2021. Snail sampling was done simultaneously by two trained personnel for fifteen minutes, once in three months. A total of 15,756 snails were collected during the study period. Eight freshwater snails were found: Bulinus globosus (n = 1396), Biomphalaria pfeifferi (n = 1130), Lymnaea natalensis (n = 1195), Bulinus tropicus (n = 1722), Bulinus forskalii (n = 195), Tarebia granifera (n = 8078), Physa acuta (n = 1579), and Bivalves (n = 461). The infection rates of B. globosus and B. pfeifferi are 3.5% and 0.9%, respectively. In our study, rainfall, pH, type of habitats, other freshwater snails and seasons influenced the distribution, abundance, and infection rates of human schistosomiasis intermediate host snails (p-value

BackgroundThe impact of climate change has led to variations in various biological processes, leading to altered transmission dynamics of infectious diseases, including snail-borne diseases (SBDs). Fascioliasis is one of the neglected zoonotic tropical snail-borne diseases caused by the trematode of the genus Fasciola. This review focused on laboratory experimental and model studies that evaluate the potential effect of temperature change on the ecology and biology of the intermediate host snails (IHS) of Fasciola.MethodsA literature search was conducted on Google Scholar, EBSCOhost, and PubMed databases using predefined medical subject heading terms, Boolean operators, and truncation symbols in combination with direct keywords: Fasciolosis AND Temperature, Lymnaea OR Austropeplea OR Radix OR Galba OR Fossaria OR Pseudosuccinea AND growth, fecundity, AND survival at the global scale. Other search terms used were (Fascioliasis AND Temperature), (Lymnaea AND Temperature), (Austropeplea AND Temperature), (Fossaria AND Temperature), (Galba AND Temperature), (Pseudosuccinea AND Temperature), and (Radix AND Temperature).ResultsThe final synthesis included thirty-five published articles. The studies reviewed indicated that temperature rise may alter the distribution, and optimal conditions for breeding, growth, and survival of IHS, ultimately resulting in changing the transmission dynamics of fascioliasis. The literature also confirmed that the life history traits of IHS and their interaction with the liver fluke parasites are driven by temperature, and hence climate change may have profound outcomes on the population size of snails, parasite density, and disease epidemiology.ConclusionWe concluded that understanding the impact of temperature on the growth, fecundity, and survival of IHS may broaden our knowledge of the possible effects of climate change and hence inform fascioliasis control programs.

The World Health Organization (WHO) recom‑ mends same‑day initiation (SDI) of antiretroviral therapy (ART) for all individuals diagnosed with HIV irrespective of CD4+ count or clinical stage. Implementation of program is still far from reaching its goals. This study assessed the level of implementation of same day ART initiation. A longitudinal study was conducted at four primary healthcare clinics in eThekwini municipality KwaZulu‑Natal. Data was collected between June 2020 to October 2020 using a data extrac‑ tion form. Data on individuals tested HIV positive, number of SDI of ART; and clinicians working on UTT program were compiled from clinic registers, and Three Interlinked Electronic Registers.Net (TIER.Net). Non‑governmental organisations (NGO) supporting the facility and services information was collected. Among the 403 individuals who tested HIV positive, 279 (69.2%) were initiated on ART on the same day of HIV diagnosis from the four facilities. There was a significant association between health facility and number of HIV positive individuals initiated on SDI (chi‑square=10.59; P‑value=0.008). There was a significant association between facilities with support from all NGOs and ART SDI (chi‑square=10.18; P‑value=0.015. There was a significant association between staff provision in a facility and SDI (chi‑square=7.51; P‑value=0.006). Urban areas clinics were more likely to have high uptake of SDI compared to rural clinics (chi‑square=11,29; P‑value=0.003). Implementation of the Universal Test and Treat program varies by facility indi‑ cating the need for the government to monitor and standardize implementation of the policy if the program is to yield success.

Introduction: Climate change alters environmental and climatic conditions, leading to expansion or contraction and possible shifts in the geographical distribution of vectors that transmit diseases. Bulinus globosus and Biomphalaria pfeifferi are the intermediate host snails for human schistosomiasis in KwaZulu-Natal (KZN) province, South Africa.Methods: Using the Maximum entropy (MaxEnt) model, we modelled the current and future distribution of human schistosomiasis intermediate host snails in KZN using two representation concentration pathways (RCP4.5 and RCP8.5) for the year 2085. Thirteen and ten bioclimatic variables from AFRICLIM were used to model the habitat suitability for B. globosus and B. pfeifferi, respectively. The Jack-knife test was used to evaluate the importance of each bioclimatic variable.Results: Mean temperature warmest quarter (BIO10, 37.6%), the number of dry months (dm, 32.6%), mean diurnal range in temperature (BIO2, 10.8%), isothermality (BIO3, 6.7%) were identified as the top four bioclimatic variables with significant contribution to the model for predicting the habitat suitability for B. globosus. Annual moisture index (mi, 34%), mean temperature warmest quarter (BIO10, 21.5%), isothermality (BIO3, 20.5%), and number of dry months (dm, 7%) were identified as the four important variables for the habitat suitability of B. pfeifferi. Area under the curve for the receiving operating characteristics was used to evaluate the performance of the model. The MaxEnt model obtained high AUC values of 0.791 and 0.896 for B. globosus and B. pfeifferi, respectively. Possible changes in the habitat suitability for B. globosus and B. pfeifferi were observed in the maps developed, indicating shrinkage and shifts in the habitat suitability of B. pfeifferi as 65.1% and 59.7% of the current suitable habitats may become unsuitable in the future under RCP4.5 and RCP8.5 climate scenarios. Conversely, an expansion in suitable habitats for B. globosus was predicted to be 32.4% and 69.3% under RCP4.5 and RCP8.5 climate scenarios, with some currently unsuitable habitats becoming suitable in the future.Discussion: These habitat suitability predictions for human schistosomiasis intermediate host snails in KZN can be used as a reference for implementing long-term effective preventive and control strategies for schistosomiasis.

This systematic review and meta-analysis aimed to collate the infection rates of Fasciola spp. in intermediate host snails and their distribution in Africa. The overall infectivity prevalences of Galba truncatula, Radix natalensis, and Pseudosuccinea columella are 52%, 8%, and 3%, respectively. The intermediate host snails native to Africa (R. natalensis and G. truncatula) have been examined more than the invasive P. columella. The studies included in the review ranged from 1999 to 2022. North Africa has the highest prevalence of G. truncatula, with an infection rate of 52%. The review reveals that naturally infected intermediate host snails (G. truncatula, R. natalensis, and P. columella) are found in various regions of Africa. G. truncatula accounts for 22% (from three countries) of the studies included in the review and it was only found in the North African region with the highest overall infection rate of 52%. More studies on infection rate and distribution are needed to effectively control and prevent future transmissions.

This study investigated the spatial distribution, abundance, and infection rates of human schistosome-transmitting snails and related physicochemical parameters and environmental factors in 11 districts in KwaZulu-Natal (KZN) province, South Africa, from December 2020–February 2021. Snail sampling was carried out in 128 sites by two people for 15 min using scooping and handpicking methods. Geographical information system (GIS) was used to map surveyed sites. In situ measurements of physicochemical parameters were recorded, while remote sensing was used to obtain measurements for climatic factors required to achieve the study's objective. Cercarial shedding and snail-crushing methods were used to detect snail infections. Kruskal-Wallis test was used to test the differences in snail abundance among snail species, districts, and habitat types. A negative binomial generalized linear mixed model was used to identify the physicochemical parameters and environmental factors influencing the abundance of snail species. A total of 734 human schistosome-transmitting snails were collected. Bu. globosus were significantly more abundant (n = 488) and widely distributed (found in 27 sites) compared to B. pfeifferi (n = 246) found in 8 sites. Bu. globosus and B. pfeifferi had infection rates of 3.89% and 2.44%, respectively. Dissolved oxygen and normalized difference vegetation index showed a statistically positive relationship, while normalized difference wetness index showed a statistically negative relationship with the abundance of Bu. globosus. However, there was no statistically significant relationship between B. pfeifferi abundance, physicochemical parameters, and climatic factors. Our study described the current distribution, abundance, and infection status of human schistosome-transmitting snails in KZN province, which will contribute to informing control measure policies for schistosomiasis.

Primary health care facilities are at the forefront of helping communities affected by natural disasters. However, such facilities are also vulnerable to the effects of extreme weather events triggered by climate change. The April 2022 floods in the south-eastern region of South Africa claimed the lives of over 400 people, the loss of 16 000 houses and resulted in major damage to infrastructure. Most damage was localised in the eThekwini area in KwaZulu-Natal, which is the country’s third most populous city. This report describes the impact of the floods on primary health care facilities in eThekwini and their preparedness for extreme weather events. Contribution: Extreme weather events induced by climate change highlight the need for primary health care facilities to develop disaster management strategies that consider climate change.

Abstract Background Schsistosomiasis is endemic in sub-Saharan Africa. It is transmitted by intermediate host snails such as Bulinus and Biomphalaria. An understanding of the abundance and distribution of snail vectors is important in designing control strategies. This study describes the spatial and seasonal variation of B. globosus and Bio. pfeifferi and their schistosome infection rates between May 2014 and May 2015 in Ingwavuma, uMkhanyakude district, KwaZulu-Natal province, South Africa. Methods Snail sampling was done on 16 sites once every month by two people for 30 min at each site using the scooping and handpicking methods. Snails collected from each site were screened for schistosome mammalian cercariae by the shedding method. The negative binomial generalised linear mixed model (glmm) was used to determine the relationship between abundances of the intermediate host snails and climatic factors [rainfall, land surface temperatures (LST), seasons, habitats, sampling sites and water physico-chemical parameters including pH and dissolved oxygen (DO)]. Results In total, 1846 schistosomiasis intermediate host snails were collected during the study period. Biompharia pfeifferi was more abundant (53.36%, n = 985) compared to B. globosus (46.64%, n = 861). Bulinus globosus was recorded at 12 sites (75%) and Bio. pfeifferi was present at 7 sites (43.8%). Biompharia pfeifferi cohabited with B. globosus at all the sites it was present. High numbers of Bio. pfeifferi (n = 872, 88.5%) and B. globosus (n = 705, 81.9%) were found between winter and mid-spring. Monthly rainfall showed a statistically significant negative relationship with the abundance of B. globosus (p

Abstract Background Bulinus species are freshwater snails that transmit the parasitic trematode Schistosoma haematobium. Despite their importance, the diversity of these intermediate host snails and their evolutionary history is still unclear in Zimbabwe. Bulinus globosus and B. truncatus collected from a urogenital schistosomiasis endemic region in the Madziwa area of Zimbabwe were characterized using molecular methods. Methods Malacological survey sites were mapped and snails were collected from water contact sites in four communities in the Madziwa area, Shamva district for a period of one year, at three-month intervals. Schistosoma haematobium infections in snails were determined by cercarial shedding and the partial mitochondrial cytochrome c oxidase subunit 1 gene (cox1) was used to investigate the phylogeny and genetic variability of the Bulinus spp. collected. Results Among the 1570 Bulinus spp. snails collected, 30 (1.9%) B. globosus were shedding morphologically identified schistosomes. None of the B. truncatus snails were shedding. The mitochondrial cox1 data from 166 and 16 samples for B. globosus and B. truncatus, respectively, showed genetically diverse populations within the two species. Twelve cox1 haplotypes were found from the 166 B. globosus samples and three from the 16 B. truncatus samples with phylogenetic analysis showing that the haplotypes fall into well-supported clusters within their species groups. Both B. truncatus and B. globosus clustered into two distinct lineages. Overall, significant negative values for both Tajima’s D statistic and the Fu’s Fs statistic were observed for B. globosus and B. truncatus. Conclusions The study provided new insights into the levels of genetic diversity within B. globosus and additional information on B. truncatus collected from a small geographical area in Zimbabwe. Low prevalence levels of infection observed in the snails may reflect the low transmission level of urogenital schistosomiasis in the area. Our results contribute towards the understanding of the distribution and population genetic structure of Bulinus spp. supporting the mapping of the transmission or risk of transmission of urogenital schistosomiasis, particularly in Zimbabwe.

Abstract Floods are one of the most devastating weather‐related hazards that are affecting millions of people over the world every year. In some poor resource areas such as Mbire District in Zimbabwe, the floods are difficult to anticipate and prepare for. Hence the need for spatial modelling of the past flood events for effective response and management. This study modelled the flood extent and depth based on data from household surveys, transect walks and a digital elevation model (DEM). A sample of 304 households was used, with 70% for calibration and 30% for validation of the flood extent. Twenty‐four flood depth measurements obtained from transect walks were used to validate the modelled flood depths based on a linear regression model. The flood depth of the worst most recent flood (January 2015) at each household was combined with altitude from the DEM using the sum function, and the inverse distance weighting was applied to model the worst flood depth. The flood extent was considered as those areas where flood depth was higher than the DEM. Approximately 24% of the area was covered by floods. The modelled flood extent agreed reasonably well with what was reported during the survey (probability of detection 0.93 and accuracy level about 0.8). Most of the areas in the wards experienced flood depths greater than 2 m, especially along the major rivers. Such areas are dangerous for people, animals and properties such as boreholes, houses, schools and clinics located on the floodplain. These results can be used for planning purposes in preparing and responding to stages of the flood management cycle. However, there is a need for further research to improve the performance and applicability of the methodology applied in this study in other settings.

Schistosomiasis is a serious water-borne disease of public health importance in southern Africa and is characterised by high morbidity and negative socio-economic repercussions. Limited knowledge on the mode of transmission and treatment contribute towards increase in the risk of infection. This study assessed community knowledge levels, perceptions and the co-constructed realities of social actors with regards to schistosomiasis in rural resource-poor communities of Ndumo in South Africa and Ntalale in Zimbabwe. We hypothesised that there was association between community knowledge level on schistosomiasis and location of residency and socio-demographic factors. Two-hundred and eight questionnaires were used to gather quantitative data on socio-demographics and knowledge levels while 18 focus group discussions were used to collect qualitative data on perceptions and social constructs. The Fisher's exact and Chi-square tests were used to determine the differences in community knowledge levels based on localities, gender, religion and age. Results showed that awareness level of schistosomiasis was assessed as ‘good’ in both Ndumo (91%) and Ntalale (81%). Majority of the respondents identified schistosomiasis as a water-borne disease with significantly higher proportion in Ndumo (89%) compared to Ntalale (68%) (p = 0.005). A significant proportion of participants in both localities were aware of the symptoms of schistosomiasis especially the passing of urine with blood (82.5% in Ndumo and 77.0% in Ntalale; p = 0.039). However, presence of schistosomiasis eggs in human stool apart from urine as a sign of infection was highly acknowledged in Ntalale (57.4%) compared to Ndumo (11.7%; p

Abstract Background During the last 30 years, the development of geographical information systems and satellites for Earth observation has made important progress in the monitoring of the weather, climate, environmental and anthropogenic factors that influence the reduction or the reemergence of vector-borne diseases. Analyses resulting from the combination of geographical information systems (GIS) and remote sensing have improved knowledge of climatic, environmental, and biodiversity factors influencing vector-borne diseases (VBDs) such as malaria, visceral leishmaniasis, dengue, Rift Valley fever, schistosomiasis, Chagas disease and leptospirosis. These knowledge and products developed using remotely sensed data helped and continue to help decision makers to better allocate limited resources in the fight against VBDs. Main body Because VBDs are linked to climate and environment, we present here our experience during the last four years working with the projects under the, World Health Organization (WHO)/ The Special Programme for Research and Training in Tropical Diseases (TDR)-International Development Research Centre (IDRC) Research Initiative on VBDs and Climate Change to integrate climate and environmental information into research and decision-making processes. The following sections present the methodology we have developed, which uses remote sensing to monitor climate variability, environmental conditions, and their impacts on the dynamics of infectious diseases. We then show how remotely sensed data can be accessed and evaluated and how they can be integrated into research and decision-making processes for mapping risks, and creating Early Warning Systems, using two examples from the WHO TDR projects based on schistosomiasis analysis in South Africa and Trypanosomiasis in Tanzania. Conclusions The tools presented in this article have been successfully used by the projects under the WHO/TDR-IDRC Research Initiative on VBDs and Climate Change. Combined with capacity building, they are an important piece of work which can significantly contribute to the goals of WHO Global Vector Control Response and to the Sustainable Development Goals especially those on health and climate action.

Abstract Background Although there has been a decline in the number of malaria cases in Zimbabwe since 2010, the disease remains the biggest public health threat in the country. Gwanda district, located in Matabeleland South Province of Zimbabwe has progressed to the malaria pre-elimination phase. The aim of this study was to determine the spatial distribution of malaria incidence at ward level for improving the planning and implementation of malaria elimination in the district. Methods The Poisson purely spatial model was used to detect malaria clusters and their properties, including relative risk and significance levels at ward level. The geographically weighted Poisson regression (GWPR) model was used to explore the potential role and significance of environmental variables [rainfall, minimum and maximum temperature, altitude, Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), rural/urban] and malaria control strategies [indoor residual spraying (IRS) and long-lasting insecticide-treated nets (LLINs)] on the spatial patterns of malaria incidence at ward level. Results Two significant clusters (p

Background:Schistosomiasis remains a public health burden in South Africa, particularly in KwaZulu-Natal. The study aimed to identify the risk factors for transmission of Schistosoma haematobium among school-going children in the Ndumo area of uMkhanyakude district, KwaZulu-Natal. Methods: A cross-sectional study involving 320 school-going children, aged 10–15 years, was conducted in 10 local primary schools in the Ndumo area, from May to June 2015. Data were collected using a structured questionnaire based on sociodemographic information, sanitation and water access, recreational, occupational activities, and knowledge about bilharzia. A filtration technique was used to detect S. haematobium eggs in 10 ml of urine. A Chi square test, bivariate and logistic regressions were performed to assess the association between variables. Odds ratios were used to determine the strength between significant predictors with 95% confidence interval and p value 0.05. Results: From the 320 participants, 120 (37.5%) were positive for Schistosoma haematobium infection. The risk factors associated with schistosomiasis were age, household head, poor sanitation, access to water source and knowledge about schistosomiasis. Conclusion: The Ndumo area is considered a moderate zone for schistosomiasis endemicity according to the World Health Organisation (WHO) classification. The significant factors identified should be considered in designing an effective schistosomiasis control program.

Abstract Background Despite its low cure rates and possible resistance, praziquantel (PZQ) is the only drug available for schistosomiasis treatment. Hence, monitoring its efficacy is crucial. This study assessed the efficacy of PZQ, determined re-infection and incidence rates of Schistosoma haematobium infection among school-going children in the Ndumo area, KwaZulu-Natal. Methods A cohort of 320 school-going children (10 – 15 years) in 10 primary schools was screened for S. haematobium infection using the filtration technique. Infected children were treated at different times and hence were divided into two sub-cohorts; A1 and A2. Non-infected children constituted the sub-cohort B. Children who continued excreting viable eggs 4 weeks post-treatment received a second dose of PZQ. Re-infection rates were determined in sub-cohort A1 and A2 at 28 and 20 weeks post-treatment, respectively. Cure rates (CR) and egg reduction rates (ERR) were calculated. Incidence rate was assessed 28 weeks post baseline survey using children that were negative for schistosome eggs at that survey. Analysis of data was done using the Chi square and the Wilcoxon rank test. A 95% confidence interval with a P-value

Abstract Background Schistosomiasis is a snail-borne disease endemic in sub-Saharan Africa transmitted by freshwater snails. The distribution of schistosomiasis coincides with that of the intermediate hosts as determined by climatic and environmental factors. The aim of this paper was to model the spatial and seasonal distribution of suitable habitats for Bulinus globosus and Biomphalaria pfeifferi snail species (intermediate hosts for Schistosoma haematobium and Schistosoma mansoni, respectively) in the Ndumo area of uMkhanyakude district, South Africa. Methods Maximum Entropy (Maxent) modelling technique was used to predict the distribution of suitable habitats for B. globosus and B. pfeifferi using presence-only datasets with ≥ 5 and ≤ 12 sampling points in different seasons. Precipitation, maximum and minimum temperatures, Normalised Difference Vegetation Index (NDVI), Normalised Difference Water Index (NDWI), pH, slope and Enhanced Vegetation Index (EVI) were the background variables in the Maxent models. The models were validated using the area under the curve (AUC) and omission rate. Results The predicted suitable habitats for intermediate snail hosts varied with seasons. The AUC for models in all seasons ranged from 0.71 to 1 and the prediction rates were between 0.8 and 0.9. Although B. globosus was found at more localities in the Ndumo area, there was also evidence of cohabiting with B. pfiefferi at some of the locations. NDWI had significant contribution to the models in all seasons. Conclusion The Maxent model is robust in snail habitat suitability modelling even with small dataset of presence-only sampling sites. Application of the methods and design used in this study may be useful in developing a control and management programme for schistosomiasis in the Ndumo area.

Schistosomiasis continues to impact socio-economic development negatively in sub-Saharan Africa. The advent of spatial technologies, including geographic information systems (GIS), Earth observation (EO) and global positioning systems (GPS) assist modelling efforts. However, there is increasing concern regarding the accuracy and precision of the current spatial models. This paper reviews the literature regarding the progress and challenges in the development and utilization of spatial technology with special reference to predictive models for schistosomiasis in Africa. Peer-reviewed papers identified through a PubMed search using the following keywords: geo-spatial analysis OR remote sensing OR modelling OR earth observation OR geographic information systems OR prediction OR mapping AND schistosomiasis AND Africa were used. Statistical uncertainty, low spatial and temporal resolution satellite data and poor validation were identified as some of the factors that compromise the precision and accuracy of the existing predictive models. The need for high spatial resolution of remote sensing data in conjunction with ancillary data viz. ground-measured climatic and environmental information, local presence/absence intermediate host snail surveys as well as prevalence and intensity of human infection for model calibration and validation are discussed. The importance of a multidisciplinary approach in developing robust, spatial data capturing, modelling techniques and products applicable in epidemiology is highlighted.