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Abstract Background Helminths are endemic in more than half of the world’s countries, raising serious public health concerns. Accurate diagnosis of helminth infection is crucial to control strategies. Traditional parasitological methods, serological tests and PCR-based assays are the major means of the diagnosis of helminth infection, but they are time-consuming and/or expensive, and sometimes provide inaccurate results. Loop mediated isothermal amplification (LAMP) assay, a sensitive, simple and rapid method was therefore developed for detection of helminths. This study aims to discuss the current status of application of LAMP on helminths detection and to make a comprehensive evaluation about this updated technology and its future outlook by comparing with several other diagnostic methods. Main body This review summarizes LAMP assay applied for helminth detection and helminthiasis surveillance. The basic principle of LAMP is introduced to help better understand its characteristics and each reported assay is assessed mainly based on its detection sensitivity, specificity and limitations, in comparison with other common diagnostic tests. Moreover, we discuss the limitations of the assays so as to clarify some potential ways of improvement. Conclusions Here, we summarize and discuss the advantages, disadvantages and promising future of LAMP in heliminth detection, which is expected to help update current knowledge and future perspectives of LAMP in highly sensitive and specific diagnosis and surveillance of helminthiasis and other parasitic diseases, and can contribute to the elimination of the diseases from endemic areas.

Young transgender women (YTGW) who sell or trade sex have among the highest HIV incidence rates in Thailand. Using qualitative methods, we assessed perceived acceptability, feasibility, and optimal design of a combination HIV prevention intervention including PrEP for YTGW. Key informant interviews were conducted during July 2016-July 2018 with 21 YTGW, aged 18-26 years, who sold sex and resided in Bangkok or Pattaya, Thailand. Grounded theory and content analysis were used for data analysis. Most YTGW interviewed reported high interest in HIV prevention research and believed participation in it supported sexual health. However, participants perceived HIV studies as complicated and time-consuming. Regarding PrEP, participants suggested more PrEP options beyond daily oral PrEP and expressed concerns related to perceived side effects of PrEP, including interaction with gender-affirming hormone therapy. Improving PrEP knowledge, being able to self-assess HIV risk, and reducing HIV/PrEP stigma could increase interest in research and PrEP uptake among YTGW.

Targeted mass primaquine treatment (TPT) might be an effective intervention to facilitate elimination of vivax malaria in Myanmar by 2030. In this study, we explored the factors hindering coverage of a TPT campaign conducted in a malarious township of northern Myanmar. From August 2019 to July 2020, a cross-sectional exploratory design including quantitative and qualitative data was conducted in five villages with high P. vivax prevalence following a TPT campaign. Among a targeted population of 2322; 1973 (85.0%) participated in the baseline mass blood survey (MBS) and only 52.0% of the total targeted population (1208, 91.9% of total eligible population) completed the TPT. G6PD deficiency was found among 13.5% of total MBS participants and those were excluded from TPT. Of 1315 eligible samples, farmers and gold miners, males, and those aged 15 to 45 years had higher percentages of non-participation in TPT. Qualitative findings showed that most of the non-participation groups were outside the villages during TPT because of time-sensitive agricultural and other occupational or education-related purposes. In addition to mitigating of some inclusion criteria (i.e. including young children or offering weekly PQ treatment to G6PD deficient individuals), strengthening community awareness and increasing engagement should be pursued to increase community participation., (© 2023. The Author(s).)

Background: Mass drug administration (MDA) with primaquine (PQ) is being considered for accelerating Plasmodium vivax elimination in remaining active foci. This study aimed to determine the acceptability of MDA with PQ in malaria endemic villages in a malarious setting in the South of Thailand undergoing MDA with PQ., Methods: A cross-sectional mixed-methods approach was conducted in seven malaria endemic villages where MDA with PQ was implemented. The data were collected from community villagers and health workers using structured questionnaires, in-depth interviews, and focus group discussions. Descriptive statistics and logistic regression models were used for quantitative data analysis. Thematic analysis was applied for qualitative data., Results: Among a total of 469 participants from the MDA villages, 293 participants were eligible for MDA with PQ and 79.86% (234) completed 14-days of PQ. The logistic regressions indicated that males (adjusted odds ratio: 2.52 [95% confidence interval: 1.33-4.81]) and those who are farmers (2.57 [1.12-5.90]) were most likely to participate in the MDA. Among 293 participants in the post-MDA study, 74.06% had originally agreed to participate in the MDA with PQ while 25.94% had originally reported not wanting to participate in the MDA. Of those who originally reported being willing to participate in the MDA, 71.23% followed through with participation in the first or second round. Conversely, 93.24% of those who originally reported not being willing to participate in the MDA did in fact participate in the MDA. Factors contributing to higher odds of agreeing to participate and following through with participation included being male (1.98 [1.06-3.69]) and correctly responding that malaria is preventable (2.32 [1.01-5.35]) with some differences by village. Five key themes emerged from the qualitative analyses: concern about side effects from taking PQ; disbelief that malaria could be eliminated in this setting; low overall concern about malaria infections; misunderstandings about malaria; and a general need to tailor public health efforts for this unique context., Conclusion: While the reported likelihood of participating in MDA was high in this setting, actual follow-through was relatively moderate, partially because of eligibility (roughly 71% of those in the follow-up survey who originally agreed to participate actually followed through with participation). One of the largest concerns among study participants was PQ-related side effects-and these concerns likely heavily influenced participant adherence to the MDA. The results of this study can be used to tailor future MDAs, or other public health interventions, in this and potentially other similar settings., (© 2023. The Author(s).)

Objectives: To explore factors associated with prescribing confidence and competence of final-year medical students for prescribing antiplatelet and fibrinolytic agents in ST-segment elevation myocardial infarction (STEMI)., Methods: The study was conducted among final-year medical students with a triangular convergent mixed-methods approach. First, an online survey was conducted using a voluntary sampling method with concurrent in-depth interviews performed. The survey data was analysed using descriptive statistics and paired t-tests, while survey factors were compared using the chi-squared or Fisher's exact test. The interview data were coded and analysed thematically. The relations between the qualitative and quantitative findings were finally described., Results: Totally 92 validly replied to the questionnaire, and 20 participated in the interviews. The quantitative analysis indicated that they had high competence in the diagnosis of STEMI and prescribing antiplatelet and fibrinolytic agents. The mean confidence score of prescribing for both was medium and was significantly lower in fibrinolytic agents. (M=3.3, SD=1.1 vs. M=2.8, SD=1.0, t (91) =5.39, p<0.01). Their experience, knowledge, and mentoring were accounted for, considering the prescribing confidence factors in both approaches. Besides, providing guidelines and standing orders were derived from the interview data., Conclusions: This study has demonstrated that final-year medical students have a high ability to diagnose and prescribe essential medications in STEMI but tend to have low confidence in prescribing fibrinolytic agents. Experiential learning, mentorship and providing guidelines can help them, especially in emergency settings to prescribe confidently and safely. Further multicenter studies on undergraduate and graduate medical students' confidence and perspective of prescribing are required, especially for high-alert medications.

Background: Radical cure of the Plasmodium vivax latent liver stage is required to effectively manage vivax malaria. Targeted mass treatment with primaquine may be an effective mechanism for reducing reservoirs of the disease. Since community engagement and high coverage are essential for mass treatment programs, this study aimed to determine the acceptability of mass primaquine treatment in a targeted community in a northern Myanmar township., Methods: A cross-sectional mixed-methods study was deployed among household leaders in July 2019. Face-to-face interviews using structured questionnaires and standardized qualitative guidelines were conducted to gather information. Descriptive and inferential statistics, including logistic regression models, were applied., Results: Among 609 study respondents, > 90% agreed to participate in an upcoming targeted mass primaquine treatment (TPT) program. Factors contributing to higher odds of acceptability of the program were older age [adjusted odds ratios (aOR): 2.38, 95% confidence intervals (CI) 1.08-8.96], secondary education level (aOR: 3.99, 95% CI 1.12-20.01), having good knowledge of malaria (aOR: 2.12, 95% CI 1.04-4.76), experiencing malaria within the family (aOR: 1.92, 95% CI 1.14-5.13), and believing eliminating malaria from the village is possible (aOR: 2.83, 95% CI 1.07-4.07). Furthermore, 50 community respondents, 6 midwives, and 4 public health staff (grade II) participated in the qualitative component of the study. Many thought that TPT seemed feasible and stressed that high coverage of underserved groups and health education are needed before commencing the activity., Conclusions: Most respondents agreed to participate in the proposed mass treatment campaign. Older people with secondary education level and those who had experienced malaria within their families were most likely to report willingness to participate. These same individuals may be important in the community engagement process to increase community acceptance of the program., (© 2021. The Author(s).)

Background: Controlling sites where mosquitos breed is a key strategy in breaking the cycle of infectious transmission of the dengue virus. Preventive behaviors, such as covering water containers with lids and adding temephos (commercially named Abate sand) in water containers are needed to reduce and control mosquito breeding sites. This study aimed to investigate the impact of dengue-preventive behaviors on Aedes immature production., Methods: This cross-sectional study used in-person interviews to record occurrence of dengue-preventive behaviors in Bang Kachao, Samut Prakan Province, Thailand. Larval mosquitos in and around houses were observed and recorded, and covered 208 households., Results: It was found that 50% of these households had containers for drinking water and 94% used water containers. Covering water containers with effective lids showed the best success among dengue-preventive behaviors for reducing Aedes immature production. Adding temephos in water containers also was effective., Conclusions: Such behaviors substantively affected development of Aedes immatures in and around households.

Phthalates are anti-androgenic chemicals and may cause long-lasting adverse effects on growing fetuses. Understanding their exposure profile during pregnancy, therefore, is of public health importance. Because both behavioral and physiological changes of pregnant women are expected to be substantial, the amount of phthalate exposure is expected to vary significantly over the course of pregnancy. Temporal trend of phthalate exposure during pregnancy, however, is largely unknown, especially in Asian women. The purpose of this study is to investigate the urinary concentrations of metabolites for major phthalates and alternative plasticizers over the course of pregnancy among Korean (n = 81) and Thai women (n = 102). Twenty-four metabolites from 15 plasticizers, such as dimethyl phthalate (DMP), diethyl phthalate (DEP), di-isobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP), benzyl butyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), dioctyl phthalate (DnOP), diisononyl phthalate (DiNP), diisodecyl phthalate (DiDP), di(2-ethylhexyl) terephthalate (DEHTP), and di-(iso-nonyl)-cyclohexane-1,2-dicarboxylate (DINCH), were measured in urine samples collected in each trimester from pregnant women. While the levels of several phthalate metabolites were significantly different by trimester among Korean women, those of Thai women were relatively consistent. Urinary metabolites of DEP and DnOP were higher in Thai pregnant women compared to Korean pregnant women. The detection frequencies of the DINCH metabolite were 67.4% and 44.9% among Korean and Thai pregnant women, respectively. However, the ratio of DINCH to DEHP metabolites was significantly higher in Thai women. According to risk assessment, 11.9% of Korean and 5.3% of Thai women were considered at risk due to phthalate exposure, and DEHP, DnBP and DiBP were identified as major risk drivers. Considering the vulnerability of growing fetuses, further studies are warranted to identify major sources of exposure to these plasticizers during pregnancy., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest regarding the publication of this article., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background: Pre-exposure prophylaxis (PrEP) is highly effective in the prevention of HIV acquisition, particularly for men who have sex with men (MSM). Questions remain on the benefits of PrEP and implementation strategies for those at occupational risk of HIV acquisition in sex work, as well as on methods to support adherence among young people who initiate PrEP., Objective: The Combination Prevention Effectiveness study for young cisgender MSM and transgender women (TGW) aims to assess the effectiveness and cost-effectiveness of a combination intervention among HIV-uninfected young MSM and TGW engaged in sex work in Thailand., Methods: This open-label, nonrandomized assessment compares the relative effectiveness of a combination prevention intervention with and without daily oral emtricitabine and tenofovir disoproxil fumarate (Truvada) PrEP with SMS-based adherence support. HIV-uninfected young MSM and TGW aged 18 to 26 years in Bangkok and Pattaya who self-report selling/exchanging sex at least once in the previous 12 months are recruited by convenience sampling and peer referral and are eligible regardless of their intent to initiate PrEP. At baseline, participants complete a standard assessment for PrEP eligibility and may initiate PrEP then or at any time during study participation. All participants complete a survey and HIV testing at baseline and every 3 months. Participants who initiate PrEP complete monthly pill pickups and may opt-in to SMS reminders. All participants are sent brief weekly SMS surveys to assess behavior with additional adherence questions for those who initiated PrEP. Adherence is defined as use of 4 or more pills within the last 7 days. The analytic plan uses a person-time approach to assess HIV incidence, comparing participant time on oral PrEP to participant time off oral PrEP for 12 to 24 months of follow-up, using a propensity score to control for confounders. Enrollment is based on the goal of observing 620 person-years (PY) on PrEP and 620 PY off PrEP., Results: As of February 2019, 445 participants (417 MSM and 28 TGW) have contributed approximately 168 PY with 95% (73/77) retention at 12 months. 74.2% (330/445) of enrolled participants initiated PrEP at baseline, contributing to 134 PY of PrEP adherence, 1 PY nonadherence, and 33 PY PrEP nonuse/noninitiation. Some social harms, predominantly related to unintentional participant disclosure of PrEP use and peer stigmatization of PrEP and HIV, have been identified., Conclusions: The majority of cisgender MSM and TGW who exchange sex and participate in this study are interested in PrEP, report taking sufficient PrEP, and stay on PrEP, though additional efforts are needed to address community misinformation and stigma. This novel multilevel, open-label study design and person-time approach will allow evaluation of the effectiveness and cost-effectiveness of combination prevention intervention in the contexts of both organized sex work and exchanged sex., International Registered Report Identifier (irrid): RR1-10.2196/15354., (©Andrea L Wirtz, Brian Wilson Weir, Sandra Hsu Hnin Mon, Pachara Sirivongrangson, Tareerat Chemnasiri, Eileen F Dunne, Anchalee Varangrat, Andrew C Hickey, Michele R Decker, Stefan Baral, Kamolnetr Okanurak, Patrick Sullivan, Rachel Valencia, Michael C Thigpen, Timothy H Holtz, Philip A Mock, Betsy Cadwell, Adeola Adeyeye, James F Rooney, Chris Beyrer, Combination Prevention Effectiveness (COPE) Study Team. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 27.01.2020.)

Background: Dengue prevention is important for controlling the spread of dengue infection. Transmission of dengue can be prevented by controlling mosquito breeding sites. Indonesia has dengue a prevention program to minimize mosquito breeding sites known as 3 M Plus. This study aimed to investigate factors associated with dengue prevention behaviour among respondents in the Lowokwaru subdistrict, an urban area in Malang, Indonesia., Methods: This cross-sectional study used a semi-structured questionnaire that was conducted by face-to-face interview., Results: Older respondents (> 60 years and 41-60 years) showed better dengue prevention behaviour than younger respondents (21-40 years and < 21 years) (p value = 0.01). Proportionally more male respondents showed poor dengue prevention behaviour compared with female respondents (p value = 0.007). Respondents who lived in Malang for long durations showed better dengue prevention behaviour compared with those who lived there for a shorter period (p value = 0.016). Those with more family members in their households practiced better dengue prevention behaviour compared with those with fewer family members (p value = 0.004). Perception was associated with dengue prevention behaviour. Respondents who had higher perceived susceptibility showed better dengue prevention behaviour compared with those who had moderate perceptions (p value = 0.000)., Conclusions: Age, gender, duration of stay in Malang, number of family members, and perception of dengue susceptibility were associated with dengue prevention behaviour.

Background: Snail-borne parasitic diseases, such as angiostrongyliasis, clonorchiasis, fascioliasis, fasciolopsiasis, opisthorchiasis, paragonimiasis and schistosomiasis, pose risks to human health and cause major socioeconomic problems in many tropical and sub-tropical countries. In this review we summarize the core roles of snails in the life cycles of the parasites they host, their clinical manifestations and disease distributions, as well as snail control methods., Main Body: Snails have four roles in the life cycles of the parasites they host: as an intermediate host infected by the first-stage larvae, as the only intermediate host infected by miracidia, as the first intermediate host that ingests the parasite eggs are ingested, and as the first intermediate host penetrated by miracidia with or without the second intermediate host being an aquatic animal. Snail-borne parasitic diseases target many organs, such as the lungs, liver, biliary tract, intestines, brain and kidneys, leading to overactive immune responses, cancers, organ failure, infertility and even death. Developing countries in Africa, Asia and Latin America have the highest incidences of these diseases, while some endemic parasites have developed into worldwide epidemics through the global spread of snails. Physical, chemical and biological methods have been introduced to control the host snail populations to prevent disease., Conclusions: In this review, we summarize the roles of snails in the life cycles of the parasites they host, the worldwide distribution of parasite-transmitting snails, the epidemiology and pathogenesis of snail-transmitted parasitic diseases, and the existing snail control measures, which will contribute to further understanding the snail-parasite relationship and new strategies for controlling snail-borne parasitic diseases.

Background: Angiostrongylus cantonensis has been the only parasite among Angiostrongylidae to cause human central nervous system infection characterized by eosinophilic meningitis or meningoencephalitis. The mechanism of the extensive neurological impairments of hosts caused by A. cantonensis larvae remains unclear. The aim of the present study was to investigate apoptosis, necroptosis and autophagy in the brains of mice infected with A. cantonensis, which will be valuable for better understanding the pathogenesis of angiostrongyliasis cantonensis., Methods: Functional and histological neurological impairments of brain tissues from mice infected with A. cantonensis were measured by the Morris water maze test and haematoxylin and eosin (H&E) staining, respectively. The transcriptional and translational levels of apoptosis-, necroptosis- and autophagy-related genes were quantified by quantitative real-time polymerase chain reaction (RT-PCR), and assessed by western blot and immunohistochemistry (IHC) analysis. Apoptotic and necroptotic cells and their distributions in infected brain tissues were analysed by flow cytometry and transmission electron microscopy (TEM)., Results: Inflammatory response in the central nervous system deteriorated as A. cantonensis infection evolved, as characterized by abundant inflammatory cell infiltration underneath the meninges, which peaked at 21 days post-infection (dpi). The learning and memory capacities of the mice were significantly decreased at 14 dpi, indicating prominent impairment of their cognitive functions. Compared with those of the control group, the mRNA levels of caspase-3, -4, -6, and RIP3 and the protein levels of caspase-4, cleaved caspase-3, cleaved caspase-6, RIP3, and pRIP3 were obviously elevated. However, no changes in the mRNA or protein levels of FADD, Beclin-1 or LC3B were evident, indicating that apoptosis and necroptosis, but not autophagy, occurred in the brain tissues of mice infected with A. cantonensis. The quantitative RT-PCR, western blot, IHC, flow cytometry and TEM results further revealed the apoptotic and necroptotic microglia, astrocytes and neurons in the parenchymal and hippocampal regions of infected mice., Conclusions: To our knowledge, we showed for the first time that A. cantonensis infection causes the apoptosis and necroptosis of microglia and astrocytes in the parenchymal and hippocampal regions of host brain tissues, further demonstrating the pathogenesis of A. cantonensis infection and providing potential therapeutic targets for the management of angiostrongyliasis.

Parasites are significant groups for carcinogenesis among which liver flukes, including Opisthorchis viverrini and Clonorchis sinensis, are typical representatives causing cholangiocarcinoma (CCA), the second most common primary hepatic malignancy with dismal prognosis. O. viverrini is prevalent in Southeast Asia, infecting 10 million people while C. sinensis has a wider distribution in East Asia and several Southeast Asian countries, affecting more than 35 million people's health. These two worms have some common characteristics and/or discrepancies in life cycle, genome, and transcriptome. As hot spots in recent years, genome and transcriptome research has extracted numerous novel fluke worm-derived proteins, which are excellent for carcinogenic exploration. However, just a handful of these studies have focused on the metabolic pathway. In this study, the main mechanisms of carcinogenesis of both worms, in terms of mechanical damage, metabolic products and immunopathology, and other possible pathways, will be discussed in detail. This review retrospectively describes the main traits of C. sinensis and O. viverrini, their molecular biology and core carcinogenic mechanisms in a contrast pattern.

Background: The influenza vaccine is recommended in older population. However the immunization coverage varies globally. It has been reported as low as 10-20 % in some countries. This study explored the acceptance of and willingness to pay for influenza vaccination, comparing acceptance and willingness to pay before and after health education., Methods: The study was conducted with 2693 older people in Bangkok, Thailand. Participants were divided into an education group (n = 1402) and a control group (n = 1291). A validated questionnaire measuring acceptance of and willingness to pay for vaccination was administered during semi-structured interviews before and after education. Data on factors influencing acceptance were analyzed., Results: Participants' mean age was 69.5 years, 80 % were women and 82.1 % had at least one co-morbidity. Of the participants, 43.5 % had previously received vaccination more than once, although 92.8 % expressed acceptance of vaccination. Acceptance was associated with a positive attitude toward vaccination (OR 2.1, 95 % CI 1.5-2.9) and a history of receiving vaccination (OR 4.1, 95 % CI 2.8-6.1). At baseline, there were no differences between the education and control groups in terms of work status (p = 0.457), co-morbidities (p = 0.07), medical status (p = 0.243), and previous vaccination (p = 0.62), except for educational background (p = 0.004). Acceptance of vaccination increased to 95.8 % (p < 0.001) after education and willingness to pay increased to 82.1 % (p < 0.001). Education significantly affected those with primary school-level education and no previous vaccination history, with acceptance increasing from 83.3 to 92.6 % (p < 0.001); more than twice as high as the control group (OR 2.4, 95 % CI 1.2-4.7). Viewing an educational video increased the proportion of participants with a high level of knowledge from 29.2 to 49.2 % (p < 0.001), and increased the proportion of participants with a positive attitude from 52.4 to 70.7 % (p <0.001). No significant difference was found in any parameter between the first and second assessment in the control group., Conclusions: The strategies to increase positive attitudes may enhance the acceptance of vaccination. Health education using an educational video demonstrated a significant impact on acceptance, willingness to pay, knowledge and attitude in older people. This may lead to increased sustainability of the immunization program in older people.

Background: Schistosomiasis is considered second only to malaria as the most devastating parasitic disease in tropical countries. Schistosome cercariae invade the host by penetrating the skin and migrate though the lungs and portal circulation to their final destination in the hepatic portal system and eventually the mesenteric veins. Previous studies have shown that the cytotoxic pathways that target schistosomulum in the lung-stage involve nitric oxide (NO) produced by macrophages. By contrast, skin-stage schistosomulas can evade clearance, indicating that they might be freed from macrophage NO-mediated cytotoxicity to achieve immune evasion; however, the critical molecules and mechanisms involved remain unknown., Methods: Recombinant SjCa8 (rSjCa8), an 8-kDa calcium-binding protein that is stage-specifically expressed in cercaria and early skin-stage schistosomulas of Schistosoma japonicum, was incubated with mouse RAW264.7 macrophages. Effects on macrophage proliferation were determined using Cell Counting Kit-8. Next, transwell assay was carried out to further investigate the role of rSjCa8 in macrophage migration. The effects of rSjCa8 on macrophage apoptosis were evaluated using confocal microscopy and flow cytometry. Additional impacts of rSjCa8 on NO release by lipopolysaccharide (LPS)-stimulated macrophages as well as the underlying mechanisms were explored using fluorescent probe, nitric oxide signaling pathway microarray, quantitative real-time PCR, mutagenesis, and neutralizing antibody approaches., Results: rSjCa8 exhibited a striking inhibitory effect on macrophage migration, but did not markedly increase cell proliferation or apoptosis. Additionally, rSjCa8 potently inhibited NO release by LPS-stimulated macrophages in a dose- and time-dependent manner, and the inhibitory mechanism was closely associated with intracellular Ca(2+) levels, the up-regulation of catalase expression, and the down-regulation of the expression of 47 genes, including Myc, Gadd45a, Txnip, Fas, Sod2, Nos2, and Hmgb1. Vaccination with rSjCa8 increased NO concentration in the challenging skin area of infected mice and reduced the number of migrated schistosomula after skin penetration by cercariae., Conclusions: Our findings indicate that SjCa8 might be a novel molecule that plays a critical role in immune evasion by S. japonicum cercaria during the process of skin penetration. The inhibitory impacts of rSjCa8 on macrophage migration and [Ca(2+)]i-dependent NO release suggest it might represent a novel vaccine candidate and chemotherapeutic target for the prevention and treatment of schistosomiasis.

Epidemiological surveys have demonstrated that helminth infections are negatively related to atopic diseases, including asthma. Defining and characterising specific helminth molecules that have excellent immunomodulatory capacities as potential therapeutics for the treatment or prophylaxis of allergic manifestations are of great interest. AcCystatin, a cystatin protease inhibitor of Angiostrongylus cantonensis, is a homologue of other nematode cystatins with immunoregulatory properties. Here, we aim to determine the effects of AcCystatin on an ovalbumin/aluminium hydroxide (OVA/Al[OH]3)-induced rat model of asthma. Wistar rats were randomly divided into four groups, including a control group, an OVA/Al[OH]3-induced asthma group, a group receiving AcCystatin immunisation prior to OVA/Al[OH]3-induced asthma and a group receiving AcCystatin treatment after OVA/Al[OH]3-induced asthma. The numbers of eosinophils, basophils, neutrophils, lymphocytes and monocytes in the peripheral blood and of eosinophils in the bronchoalveolar lavage fluid (BALF) were counted for each animal. The expression levels of the cytokines interferon-γ, interleukin (IL) 4, IL-5, IL-6, IL-10, IL17A and tumour necrosis factor receptor-α in BALF, of OVA-specific immunoglobulin E in BALF and serum and of the chemokines eotaxin-1, eotaxin-2, eotaxin-3, MCP-1 and MCP-3 in lung tissue were measured. In addition, the degree of peribronchial and perivascular inflammation and the intensity of goblet cell metaplasia were qualitatively evaluated. The sensitised/challenged rats developed an extensive cell inflammatory response of the airways. AcCystatin administration significantly reduced the cellular infiltrate in the perivascular and peribronchial lung tissues and reduced both goblet mucous production and eosinophil infiltration. The rats that were treated with AcCystatin before or after sensitisation with OVA showed significant decreases in eotaxin-1, eotaxin-3 and MCP-1 expression in the lung tissue. The production of IL-4, IL-5, IL-6 and IL-17A and of OVA-specific IgE antibodies was also significantly reduced in AcCystatin-treated rats compared with untreated asthmatic rats. The AcCystatin treatment was associated with a significant increase in IL-10 levels. Our present findings provide the first demonstration that AcCystatin is an effective agent in the prevention and treatment of the airway inflammation associated with asthma.

Background: Schistosomiasis japonicum remains a considerable economic and public health concern in China, the Philippines and Indonesia. Currently available measures to control the unique intermediate host Oncomelania hupensis are frequently associated with severe side effects. Previous studies have demonstrated that linalool-rich extracts from various plants exhibited promising biological activities including cytotoxic, anti-microbial and anti-parasitic properties., Methods: We identified the components of leaf extracts from Cinnamomum camphora by gas chromatography coupled to mass spectrometry (GC-MS) and investigated molluscicidal and larvicidal effects of linalool against O. hupensis and Schistosoma japonicium. The ultrastructural alterations in gills, salivary gland, stomach and hepatopancreas of snails were observed under the light microscope and transmission electron microscope, and lesions to tegument of cercaria were examined under a light microscope and fluorescence microscope. We then evaluated the effects of linalool on skin penetration and migration of schistosomula and adult survival by measurement of worm burden and egg counts in Balb/C mice infected with linalool-treated cercariae., Results: In the present work, 44 components were identified from the leaf extracts of C. camphora, of which linalool was the most abundant constituent. Linalool exhibited the striking molluscicidal and larvicidal effects with LC50 = 0.25 mg/L for O. hupensis and LC50 = 0.07 mg/L for cercaria of S. japonicium. After exposure to linalool, damage to the gills and hepatopancreas of the snails, and to the tegument and body-tail joint of cercariae was apparent. In addition, linalool markedly reduced the recovered schistosomulum from mouse skin after challenge infection, and therefore decreased the worm burden in infected animals, but not fecundity of female adults of the parasite., Conclusions: Our findings indicated that linalool might be a novel chemotherapeutic agent against S. japonicium and the snail intermediate host.

This is the first report of the large-scale utilization of migrants as health volunteers in a migrant primary-healthcare program. The program recruited migrants who volunteered to serve their communities. This study explores the identities of these volunteers, their relationship with program management, and their attitudes. The study also investigates the impact of the volunteers, from the migrants' and healthcare workers' perspective. The study was conducted in two provinces, Tak (northern Thailand) and Samut Sakhon (central Thailand). Primary and secondary information was collected. Mixed methods, comprising in-depth interviews, observation and questionnaires, were used to gather primary data from three groups of participants-migrant volunteers, migrants and healthcare workers. Secondary data, and in-depth interviews with healthcare workers, showed that migrant volunteers made a significant contribution to the provision of both preventive and curative services. The quantitative study covered 260 migrant volunteers and 446 migrants. The results found that <5% of volunteers were selected by the community. Almost all attended a training course. Most were assigned to be health communicators; four stated they did nothing. Volunteers' attitudes were very positive. Most migrants reported that the volunteers' work was useful. It was concluded that the migrant health-volunteer program did help deal with migrant health problems. However, management of the program should be closely considered for more effective outcomes.

This evaluative research study aimed to assess the effects of the central healthcare incinerator project on waste management in Yala Province. The study data were collected twice: at baseline and during the operational phase. A combination of structured interview and observation were used during data collection. The study covered 127 healthcare facilities: government hospitals, healthcare centres, and private clinics. The results showed 63% of healthcare risk waste (HCRW) handlers attended the HCRW management training. Improvements in each stage of the HCRW management system were observed in all groups of facilities. The total cost of the HCRW management system did not change, however; the costs for hospitals decreased, whereas those for clinics increased significantly. It was concluded that the central healthcare waste incinerator project positively affected HCRW management in the area, although the costs of management might increase for a particular group. However, the benefits of changing to a more appropriately managed HCRW system will outweigh the increased costs.

Setting: Chest Clinic, Ministry of Public Health and health care centres, Bangkok Metropolitan Administration., Objective: To determine patient factors predicting successful tuberculosis (TB) treatment., Design: A prospective cohort was conducted during May 2004 to November 2005. Newly diagnosed TB patients aged > or = 15 years were recruited after giving informed consent. Three sets of questionnaires were used to collect data from the patients three times. Data were also gathered from treatment cards., Results: Of 1241 patients, 81.1% were successfully treated. Bivariate analysis indicated that patients' sex, education, occupation, level of knowledge about TB and adverse effects were associated with treatment success. Unconditional logistic regression analysis showed that females had a higher success rate than males (OR = 1.9, 95%CI 1.2-2.9). Patients with regular incomes had twice the likelihood of success of the unemployed (OR = 2.0, 95%CI 1.1-3.5). Patients with high knowledge levels were more likely to complete treatment (OR = 2.0, 95%CI 1.2-3.4), while those with adverse effects were less likely to adhere (OR = 0.6, 95%CI 0.4-0.9)., Conclusion: The current low treatment success rate may be partly due to inadequate knowledge about TB among patients. Improvements in health education and early detection and management of adverse effects should be prioritised by the National Tuberculosis Programme.

Setting: All health care centres under the Department of Health, Bangkok Metropolitan Administration., Objectives: To investigate patterns of drug administration for tuberculosis (TB) patients and to determine whether these patterns affect treatment success rates., Design: In a prospective cohort study conducted during May 2004 to November 2005, newly diagnosed TB patients aged > or = 15 years were enrolled after giving informed consent. The cohort was followed until treatment outcome. Structured questionnaires were used to interview patients three times: at the first visit, at the end of the intensive phase and at treatment completion. Data were also collected from treatment cards., Results: Five patterns of drug administration were used in the health centres: centre-based directly observed treatment (DOT), family-based DOT, self-administered treatment (SAT), centre-based DOT + SAT and centre- + family-based DOT. The pattern of drug administration had a significant impact on treatment success (P < 0.001). Using unconditional binary multiple logistic regression controlling for confounding factors, centre- + family-based DOT had the highest success rates compared with centre-based DOT (OR 20.9, 95%CI 5.0-88.3)., Conclusion: The pattern of drug administration impacted on treatment success. Centre- + family-based DOT, family-based DOT and centre-based DOT + SAT achieved higher rates of treatment success than the World Health Organization target. Centre-based DOT had the lowest success.

The informed consent process has become a universal requirement for research involving human subjects. Its goal is to inform volunteers regarding research in order to make decision to participate or not. This study aimed to measure volunteers' comprehension levels concerning the clinical trial and to find out factors associated with that comprehension levels. Eighty-one volunteers who enrolled in a malaria clinical trial were recruited into the study. A semi-structured questionnaire was used to collect the information. Non-participant observation was used to observe the process of informed consent. Volunteers were interviewed three days after being recruited into the trial. The results show the volunteers' comprehension was low. Only 44% of volunteers had an acceptable level of comprehension. It also revealed that 20 volunteers were not aware of being volunteers. Most volunteers knew about the benefits of participating in the trial and realized that they had the right to withdraw from the study, but not many knew about the risks of the trial. The results indicated the method of informing about the trial affected the volunteers' comprehension level. No relationship was found between comprehension level and volunteers' socio-demographic characteristics and their attitude toward the consent process. The findings from this study demonstrate volunteers who participated in the clinical trial were not truly informed. Further studies regarding enhancing volunteers' understanding of the trial are needed.

A potential test for early detection of dementia in the elderly is the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), which is based on information from the informant for the elderly about the changes of the elderly in everyday cognitive functioning associated with dementia. The present study aimed to modify and assess the reliability and validity of the modified IQCODE consisting of 32 items. The study consisted of two methods of assessing dementia: DSMIV diagnosis carried out by clinicians, and informants responding to the IQCODE. The subjects were 200 pairs of elderly subjects and their informants who visited the Geriatric Clinic, Ramathibodi Hospital. The optimal cutoff score on the modified IQCODE was 3.42, with 90% sensitivity and 95% specificity. The positive predictive values, negative predictive values, and accuracy were 0.94, 0.90, and 0.92, respectively. The IQCODE items had high internal consistency. The IQCODE associated with the elderly person's age, but not with their gender and educational level; nor were they associated with the demographic characteristics of the informant. Therefore, the IQCODE could be used as an alternative screening test for dementia in Thailand with acceptable sensitivity and specificity. This tool may be useful for dementia screening in the community and the geriatric clinic for early detection of disease.

This descriptive cross-sectional study was conducted to investigate gender differences in the epidemiological factors associated with the treatment seeking behaviors of TB cases in the rural communities of Bangladesh. The study reveals that there is significant gender difference in treatment seeking behaviors of rural TB cases and the majority of them (52%) have taken prior treatment from various traditional healers, 70% of them are females who attended health centers (UZHCs) as the other choice (adjusted OR: 4.2, 95% CI: 2.0-8.4). It was found that the mean patient delay was 63 days (range 14-210 days) where half of the females delayed more than 60 days while they were spreading their disease. The study findings reveal gender differences in treatment seeking behaviors associated with socio-cultural barriers, particularly among females in their access to TB care. Fifty-five percent of cases wanted the diagnosis of TB remain confidential to avoid being labeled as TB patients, where 82.7% were female, 85.6% of female TB patients had problems in their relationships with their spouse (61%) and family members (58%) after being diagnosed with TB. The results of the TB service factors found that 39% of females were not satisfied with their provider's behaviors, which was significantly associated with treatment seeking behavior (adjusted OR: 2.6, 95% CI: 1.0-6.6). The study findings strongly suggest that there was a significant gender difference in treatment seeking behavior in rural Bangladesh. Based on the study findings, we recommend developing an appropriate gender strategy for developing a TB control program, comprised of operational, socio-cultural and community awareness interventions aimed at treating undiscovered reservoirs of female TB cases in rural Bangladesh.

The economic burden of DHF patients and of the Thai government in providing treatment and prevention and control of dengue hemorrhagic fever were assessed. Patient burden was reported by caretakers who stayed with the patients when they were admitted to three hospitals: Children's Hospital in Bangkok; Suphan Buri Provincial Hospital and Don Chedi Community Hospital, Don Chedi District in Suphan Buri Province. The hospital costs--medicine and laboratory costs--were collected from the treatment forms and the routine service cost was estimated by the staff of the hospitals. Cost of prevention and control were compiled from the budget report of Departments of the Ministry of Public Health and the Ministry of Interior. Based on 184 DHF patients admitted at the three hospitals, the direct patient costs--treatment cost and the costs of travel, food and lodging--was 66.99 US$ and 61.02 US$ per patient for one episode of DHF in Bangkok and Suphan Buri, respectively. The total patient costs--direct patient costs and opportunity costs were 118.29 US$ for a child patient and 161.49 US$ for an adult patient in Bangkok, 102.82 US$ for a child patient and 138.02 US$ for an adult patient in Suphan Buri. The net hospital cost in providing treatment for each DHF patient was 54.6 US$ and 38.65 US$ in Bangkok and Suphan Buri, respectively. The total cost of prevention and control of DHF in Thailand from government agencies in 1994 was 4.8724 million US$. Based on these findings, the whole expenditure of Thailand for DHF in 1994, would be at least 12.596 million US$, of which 54.8% was from the government budget, the rest, 45.2%, was the expenses paid by 51,688 patients and their families. The study concluded that in recording the economic-loss of DHF both the expenditures of the government and also the patient costs--direct and indirect--should be taken into account.

A study on treatment seeking behavior of dengue hemorrhagic fever (DHF) patients was made from 184 clinically diagnosed patients in three hospitals: Children's Hospital, Bangkok; Suphan Buri Provincial Hospital, Suphan Buri Province and Don Chedi Community Hospital in the district of Don Chedi, Suphan Buri Province. The information was collected by interviewing the patients' caretakers while they were attending the patients in the hospitals, using a series of closed- and open-ended questions. Based on the first place of treatment, five patterns of treatment seeking behavior were identified, the most common one was using the clinic as the first step. Different patterns of treatment seeking behavior had the impact on the duration of illness, the number of steps in seeking treatment and the direct patient costs. The socio-demographic characteristics of the patient's caretaker that influenced the decision making to take treatment alternatives included the level of education, occupation, residential area and lay symptom assessment. In addition, economic factors: the capability to reimburse the cost of treatment, the family income and the financial sources, were also important for caretakers to take into consideration when making treatment choices.

The focus of this paper is on community participation in the Thai Malaria Control Program. Two projects concerned are reviewed. First, the Village Voluntary Malaria Collaborator Program has been established for case detection. Second, the Village Malaria Self-Reliance Project aims at malaria prevention. Both projects have been able to get community participation at a certain level. The success of the projects depend on the community, the structures of the projects and the malaria situation in the communities.

In the Malaria Control Program of Thailand, villagers were recruited as village malaria volunteers to assist and participate in passive case detection at the community level by preparation of blood smears and provision of presumptive treatment to suspected cases. Among these volunteers, there were some folk healers. This study was intended to investigate the role of the folk healer volunteer in the Malaria Control Program in the northern area under the responsibility of the Malaria Zone 1, Region 2 in Fang, Mae Ai and Chiang Dao Districts of Chiang Mai Province. The combination of qualitative and quantitative research methodologies (participant and non-participant observations and structured questionnaires) were used to get information from 246 volunteers, of whom 113 were folk healers. Most of the volunteers were male and more than half were in the age group 30-50 years. Almost all volunteers had completed the compulsory education and farming was their main occupation. Folk healer volunteers were older and had been in the service longer than the non-folk healer volunteers. Both groups of volunteers shared some negative attitudes towards the Malaria Control Program, such as the interference with their occupation and the waste of time. However, the folk healer volunteers had more positive attitudes towards the program in terms of gaining social respect and the willingness to stay on. It was also found that the folk healer volunteers performed their assignment better than the non-folk healer volunteers.(ABSTRACT TRUNCATED AT 250 WORDS)

The preliminary results of a study of rural-rural migration in an endemic area of malaria is reported. The study on socio-economic status of migrant workers was made during the post planting season of sugarcane plantation in Tambon Nong Rhee Kanchanaburi Province. Among 9,311 population in four villages of this Tambon, 15.4% were migrants and 45.5% were from the northeast provinces of Thailand. Almost half of the migrant population came to the area for the first time and stayed for six months mostly during the sugarcane cutting season. No significant difference in experience with malaria (as recognized by the people not from blood examination) between the local population and the migrants was observed from the interview. However, the duration of migration seemed to relate with the risk of contracting malaria.