Associations of effort-reward imbalance at work and quality of life among workers after stroke: a one-year longitudinal study in Thailand.

Stroke incidence is increasing among working-age population, but the role of psychosocial stress in the workplace in predicting quality of life (QoL) after stroke onset is understudied. This longitudinal study aimed to investigate the relationship between work stress, measured by the effort-reward imbalance (ERI) model, and QoL over one-year period among 103 Thai workers who had experienced a stroke. The study evaluated the effort (E)-reward (R) ratio and over-commitment, the extrinsic and intrinsic components of the ERI model, before discharge; QoL was repeatedly measured at baseline, six months, and 12 months after discharge, respectively, using the Short Form Version 2 (SF-12v2) indicators of physical and mental health composite scores. Generalized estimating equations were used to examine longitudinal relationships between work stress at baseline and QoL over one year by testing the hypotheses that E-R ratio and over-commitment would have direct effects on QoL, and potential moderating effects of over-commitment on E-R ratio and QoL. The results supported the ERI model partially, as over-commitment was significantly associated with poor mental health (coefficient - 8.50; 95% CI: -13.79, -3.20) after adjusting baseline sociodemographic, behavioral, and clinical characteristics, while the E-R ratio was not significantly associated with physical or mental health; the interaction between the E-R ratio and over-commitment was also not significant. These findings suggest that more attention should be paid to workers' personal coping skills and ability to handle work-related problems and prioritize interventions that address over-commitment to promote long-term mental health among workers with stroke.

Corrigendum: Handwashing among caregivers of young children in a protracted and complex refugee and immigration context: a mixed methods study on the Thai-Myanmar border.

[This corrects the article DOI: 10.3389/fpubh.2023.1099831.].

Handwashing among caregivers of young children in a protracted and complex refugee and immigration context: a mixed methods study on the Thai-Myanmar border.

Introduction: Protracted refugee situations create complex contexts that present significant health risks for young children. Effective hand hygiene practices by caregivers can reduce respiratory infections and diarrhoeal disease, the two largest contributors to mortality among children between 1 month and 5 years of age. This study documented handwashing patterns and access to water, sanitation and hygiene (WASH) infrastructure among caregivers of young children living along the Thai-Myanmar border, one of the world's most protracted and complex refugee and immigration contexts. It also examined the association between handwashing and socio-demographic variables and captured participants' explanations for when and how hands are washed. The study broadened the scope of previous research by also including the large number of caregivers living outside formal camps. Methods: Caregivers of children attending 11 preschools in Tak province, Thailand participated in a mixed-methods cross-sectional study. Quantitative questionnaire data (n = 384) were supplemented by a thematic analysis of data from in-depth interviews (n = 9). Results: Fewer than half the caregivers reported routinely washing their hands before preparing meals or after using the latrine/toilet. Fewer than one-in-five routinely used soap in these situations. Interviewees explained that handwashing was only necessary when a substance could be felt or seen, in which case wiping with a cloth or a rinsing with water were sufficient to clean hands. However, their explanations also suggested some potential avenues for culturally appropriate and feasible interventions to improve hand hygiene. Conclusion: The results confirmed previous research on the multi-dimensional barriers to good hand hygiene in protracted refugee situations and other low-resource settings. Additional investment to overcome shortages in the infrastructure necessary to support good hand hygiene and creative means of drawing on and developing human capital will be necessary to realize the potential hand hygiene holds for reducing ill-health and mortality among young children living in these contexts.

Efficacy of household Aedes larval control practices in a peri-urban township, Yangon, Myanmar: Implication for entomological surveillance.

Dengue is a major public health concern in Myanmar. We carried out a cross-sectional study to investigate the efficacy of larval control practices in household water containers, such as the use of the larvicide, temephos, covering the containers with lids and weekly cleaning. We surveyed 300 households in Kaw Hmu Township, a peri-urban community in the Yangon region. We inspected 1,892 water storage containers and 342 non-water storage/household waste containers during the rainy season and 1,866 water storage containers and 287 non-water storage/household waste containers during the dry season. The presence of Aedes larvae and larval control measures were recorded for each container. Results revealed that larval indices were higher than World Health Organization standard indices, and infestations in water storage containers were more common in the rainy season (6.6%) than in the dry season (5.7%). Infestations were also more likely in containers of non-potable water (9.1%-9.9%) than in containers of potable water (0.1%-0.7%). Two thirds of water storage containers were treated with temephos. Containers most likely to contain Aedes larvae were cement basins and barrels. Temephos was effective in controlling infestations in cement basins, while weekly cleaning was effective in controlling infestations in barrels. Combinations of control methods were more effective at larval control than the use of a single method. Larval infestations were high (18.4% in the rainy season) in unused containers and in containers which were household waste. Overall, we found a complex interaction between household water use, container characteristics, and larval control practices. Larval control strategies in Myanmar will require ongoing entomological surveillance and the identification of key breeding sources and optimal control methods.

Effectiveness of dengue training programmes on prevention and control among high school students in the Yangon region, Myanmar.

Background: Dengue is one of the health problems in Myanmar. Thus, health promotion in schools is considered a key approach for reducing risk-taking behaviours related to dengue. Objectives: The study aimed to evaluate a dengue training programme for high school students to measure changes in knowledge, attitude and practices (KAP) towards dengue; evaluate the effectiveness of the programme in improving prevention and control practices among families and determining changes in larval indices in their dwelling places. Methodology: The dengue school training programme was conducted for Grades 9 and 10 students in Yangon. In total, 300 students in the intervention school received training and were compared with 300 students as control. KAP was assessed using a self-administered questionnaire, whereas larval and control practice surveys were conducted at the homes of both groups 3 months before and after the programme. Results: The KAP scores of the intervention group increased after the programme. Moreover, the programme improved prevention and control practices and decreased the larval indices in the intervention group. Students from the same group with high scores in knowledge and self-reported practices were less likely to exhibit Aedes larval positivity in their residential areas. Conclusion: This study demonstrated the impact of the dengue training programme on the KAP of students and short-term family larval control practices, which influenced household larval indices.

Community acceptability, participation, and adherence to mass drug administration with primaquine for Plasmodium vivax elimination in Southern Thailand: a mixed methods approach.

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.

HIV and syphilis knowledge, perceptions, and practices among Myanmar migrant workers in Samut Sakhon Province, Thailand.

BACKGROUND: Thailand has been one of the largest migration hubs in Southeast Asia for the past four decades and keeps attracting migrants from neighboring countries. Due to difficulties associated with their status, migration can place individuals at a heightened risk for sexually transmitted diseases. This study aimed to examine factors influencing HIV and syphilis preventive behaviors among Myanmar migrants in Samut Sakhon, Thailand. METHODS: A cross-sectional mixed-method study was conducted among Myanmar migrants aged 18 years and above in Samut Sakhon Province, Thailand. To fulfill this study's aims, four hundred seventy-three respondents completed a survey to provide quantitative data, and eight participants completed in-depth qualitative interviews. The factors associated with protective sexual behaviors were identified with multiple logistic regression analysis of the quantitative study data and thematic analysis of the qualitative data. RESULTS: The respondents showed good knowledge of HIV and syphilis (50.1%), but over half (55.6%) exhibited the negative perception of sexually transmitted disease prevention; about 81.4% of male respondents never used a condom when they had sexual intercourse in the past year. Based on multivariate analysis, income expenses-balance (adjusted odds ratio (AOR) = 2.379, 95% confidence interval (CI): 1.002-5.731, p = 0.049), number of sex partners (AOR = 3.044, 95% CI: 1.339-6.924, p = 0.008), and having sex with a prostitute (AOR = 6.085, 95% CI: 1.28-28.918, p = 0.023) were all statistically associated with unprotected sex. In the qualitative analysis, knowledge, understanding, beliefs; the influence of culture, community, and environment; and condom perceptions were also important factors. CONCLUSION: Low use of condoms in sexual practice was identified, and the appropriate intervention or approach to improve the utilization of condoms in the community was provided.

Multidisciplinary Investigations of Sustained Malaria Transmission in the Greater Mekong Subregion.

In the course of malaria elimination in the Greater Mekong Subregion (GMS), malaria epidemiology has experienced drastic spatiotemporal changes with residual transmission concentrated along international borders and the rising predominance of Plasmodium vivax. The emergence of Plasmodium falciparum parasites resistant to artemisinin and partner drugs renders artemisinin-based combination therapies less effective while the potential spread of multidrug-resistant parasites elicits concern. Vector behavioral changes and insecticide resistance have reduced the effectiveness of core vector control measures. In recognition of these problems, the Southeast Asian International Center of Excellence for Malaria Research (ICEMR) has been conducting multidisciplinary research to determine how human migration, antimalarial drug resistance, vector behavior, and insecticide resistance sustain malaria transmission at international borders. These efforts allow us to comprehensively understand the ecology of border malaria transmission and develop population genomics tools to identify and track parasite introduction. In addition to employing in vivo, in vitro, and molecular approaches to monitor the emergence and spread of drug-resistant parasites, we also use genomic and genetic methods to reveal novel mechanisms of antimalarial drug resistance of parasites. We also use omics and population genetics approaches to study insecticide resistance in malaria vectors and identify changes in mosquito community structure, vectorial potential, and seasonal dynamics. Collectively, the scientific findings from the ICEMR research activities offer a systematic view of the factors sustaining residual malaria transmission and identify potential solutions to these problems to accelerate malaria elimination in the GMS.

The acceptability of targeted mass treatment with primaquine for local elimination of vivax malaria in a northern Myanmar township: a mixed-methods study.

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.

Ownership and utilization of bed nets and reasons for use or non-use of bed nets among community members at risk of malaria along the Thai-Myanmar border.

BACKGROUND: With the goal for malaria elimination in Thailand set for 2024, increased coverage and utilization of bed net, especially insecticide-treated net (ITN) or long-lasting insecticidal net (LLIN) is a key strategy. This study aims to provide the necessary information about bed net ownership and utilization among the population at risk of malaria living along the Thai-Myanmar border in Tak province. METHODS: A cross-sectional study was conducted using a mixed-method approach in 331 households from 5 hamlets in the villages of the Thai-Myanmar border. The research tools included a questionnaire, bed net inspection, and semi-structured interviews. Logistic regression was used to explore the sociodemographic factors associated with bed net utilization. The qualitative analysis employed a thematic analysis approach. RESULTS: This survey found that 98.5% of households had at least one bed net per household, and 74.3% had at least one ITN/LLIN. However, only 30.8% of households reached the standard policy set by the Minister of Public Health of one ITN/LLINs per two persons. Most residents used bed net (92.1% used in the previous night and 80.9% used every day). For those using bed nets, however, 61.9% used ITNs or LLINs the night before and 53.1% used them every day. Nonetheless, the usage rates of bed nets (any type) in the previous night among children and pregnant women were high, reaching 95.3% and 90.0%, respectively. Seven explanatory variables showed statistically significant associations with bed net use every day, including: "not staying overnight in the forest or the field", "sleeping pattern based on gender", "sufficient numbers of bed nets to cover all sleeping spaces", "preference for free bed nets", "age", "gender", and "SES score" showed statistically significant association with bed net use every day. The major reasons for the regular use of bed nets in both household and the forest were to prevent mosquito biting. The reasons for not using bednets in the household were discomfort feelings from heat, perception of unnecessity due to low mosquito density, whereas the reason for not using bed nets in the forest was inconvenience. CONCLUSION: Despite that overall coverage and usage of bed nets was high, only one third reached the standard level specified by the policy. Overnight in the forest, the dissatisfaction with the quality of free bed nets, insufficient number of bed nets, sleeping alone, male gender, age more than 10 years, low socioeconomic status, discomfort from heat, perception of no benefits of bed nets due to low mosquito density, and inconvenience were factors influencing bed net use. Maintaining high coverage and utility rate of bed nets should be a priority for the malaria high-risk population.

Field evaluation of the gut microbiome composition of pre-school and school-aged children in Tha Song Yang, Thailand, following oral MDA for STH infections.

Soil-transmitted helminths, such as roundworms (Ascaris lumbricoides), whipworms (Trichuris trichiura) and hookworms (Necator americanus and Ancylostoma spp.), are gastrointestinal parasites that occur predominantly in low- to middle-income countries worldwide and disproportionally impact children. Depending on the STH species, health status of the host and infection intensity, direct impacts of these parasites include malnutrition, anaemia, diarrhoea and physical and cognitive stunting. The indirect consequences of these infections are less well understood. Specifically, gastrointestinal infections may exert acute or chronic impacts on the natural gut microfauna, leading to increased risk of post-infectious gastrointestinal disorders, and reduced gut and overall health through immunomodulating mechanisms. To date a small number of preliminary studies have assessed the impact of helminths on the gut microbiome, but these studies are conflicting. Here, we assessed STH burden in 273 pre-school and school-aged children in Tha Song Yang district, Tak province, Thailand receiving annual oral mebendazole treatment. Ascaris lumbricoides (107/273) and Trichuris trichiura (100/273) were the most prevalent species and often occurred as co-infections (66/273). Ancylostoma ceylanicum was detected in a small number of children as well (n = 3). All of these infections were of low intensity (<4,999 or 999 eggs per gram for Ascaris and Trichuris respectively). Using this information, we characterised the baseline gut microbiome profile and investigated acute STH-induced alterations, comparing infected with uninfected children at the time of sampling. We found no difference between these groups in bacterial alpha-diversity, but did observe differences in beta-diversity and specific differentially abundant OTUs, including increased Akkermansia muciniphila and Bacteroides coprophilus, and reduced Bifidobacterium adolescentis, each of which have been previously implicated in STH-associated changes in the gut microfauna.

Glucose-6-phosphate dehydrogenase mutations in malaria endemic area of Thailand by multiplexed high-resolution melting curve analysis.

BACKGROUND: Glucose-6-phosphate dehydrogenase (G6PD) deficiency, the most common enzymopathy in humans, is prevalent in tropical and subtropical areas where malaria is endemic. Anti-malarial drugs, such as primaquine and tafenoquine, can cause haemolysis in G6PD-deficient individuals. Hence, G6PD testing is recommended before radical treatment against vivax malaria. Phenotypic assays have been widely used for screening G6PD deficiency, but in heterozygous females, the random lyonization causes difficulty in interpreting the results. Over 200 G6PD variants have been identified, which form genotypes associated with differences in the degree of G6PD deficiency and vulnerability to haemolysis. This study aimed to assess the frequency of G6PD mutations using a newly developed molecular genotyping test. METHODS: A multiplexed high-resolution melting (HRM) assay was developed to detect eight G6PD mutations, in which four mutations can be tested simultaneously. Validation of the method was performed using 70 G6PD-deficient samples. The test was then applied to screen 725 blood samples from people living along the Thai-Myanmar border. The enzyme activity of these samples was also determined using water-soluble tetrazolium salts (WST-8) assay. Then, the correlation between genotype and enzyme activity was analysed. RESULTS: The sensitivity of the multiplexed HRM assay for detecting G6PD mutations was 100 % [95 % confidence interval (CI): 94.87-100 %] with specificity of 100 % (95 % CI: 87.66-100 %). The overall prevalence of G6PD deficiency in the studied population as revealed by phenotypic WST-8 assay was 20.55 % (149/725). In contrast, by the multiplexed HRM assay, 27.17 % (197/725) of subjects were shown to have G6PD mutations. The mutations detected in this study included four single variants, G6PD Mahidol (187/197), G6PD Canton (4/197), G6PD Viangchan (3/197) and G6PD Chinese-5 (1/197), and two double mutations, G6PD Mahidol + Canton (1/197) and G6PD Chinese-4 + Viangchan (1/197). A broad range of G6PD enzyme activities were observed in individuals carrying G6PD Mahidol, especially in females. CONCLUSIONS: The multiplexed HRM-based assay is sensitive and reliable for detecting G6PD mutations. This genotyping assay can facilitate the detection of heterozygotes, which could be useful as a supplementary approach for high-throughput screening of G6PD deficiency in malaria endemic areas before the administration of primaquine and tafenoquine.

Effective low-cost preservation of human stools in field-based studies for helminth and microbiota analysis.

Molecular studies of gastrointestinal infections or microbiotas require either rapid sample processing or effective interim preservation. This is difficult in remote settings in low-income countries, where the majority of the global infectious disease burden exists. Processing or freezing of samples immediately upon collection is often not feasible and the cost of commercial preservatives is prohibitive. We compared fresh freezing (the 'gold standard' method), with low-cost chemical preservation in (i) a salt-based buffer consisting of DMSO, EDTA and NaCl (DESS) or (ii) 2.5% potassium dichromate (PD), for soil-transmitted helminth detection and microbiota characterisation in pre-school and school-aged children from north-western Thailand. Fresh frozen samples were frozen at -20°C on collection and maintained at -80°C within ~3 days of collection until molecular analysis, with international shipping on dry ice. In contrast, chemically preserved samples were collected and stored at ~4°C, transported on wet ice and only stored at -20°C on arrival in Australia ~8 weeks after collection, with international shipping on wet ice. DESS and PD provided better sensitivity for STH diagnosis, estimating higher infection rates (>80% for Ascaris lumbricoides and >60% for Trichuris trichiura; versus 56% and 15% for these parasites in fresh frozen samples) and egg abundance (inferred as gene copy number estimates). All methods performed similarly for microbiota preservation, showing no significant differences in alpha-diversity based on overall richness or inverted Simpson's Index. All three methods performed similarly for RNA and protein preservation in a small subset of samples. Overall, DESS provided the best performance, with the added benefit of being non-toxic, compared with PD, hence making it particularly applicable for studies in remote and resource-poor settings.

Perception and belief in oral health among Karen ethnic group living along Thai-Myanmar border, Thailand.

BACKGROUND: Utilization of oral health services has been low among rural populations in Thailand, especially for minority ethnicity populations living along the borders. The aim of this study was to increase understanding of the determinants of the underutilization of oral health services among these populations. METHODS: A qualitative study using in-depth interview and semi-structured interview was conducted among participants of Karen ethnicity living in Mae Tan Sub-district, Thasongyang District, Tak Province, Thailand. The interviews focused on exploring the participants' perceptions of oral health problems, oral health and hygiene, and oral health-seeking behaviors. The verbatim-transcribed interviews were analyzed using thematic analysis. RESULTS: A total of 101 participants (50 adults and 51 children) with a Karen ethnic background took part in the interviews. Most participants could not identify oral health problems and did not perceive dental disease as a problem unless there was severe pain that could not be relieved by painkillers. The Karen ethnic community worked as subsistence farmers, and their busy daily activities consisted of farming, going to the forest to hunt and gather, performing housework, and taking care of their children. Dental health was given a lower priority compared with general health. The perceived value of primary teeth was low, which was identified as an underlying factor resulting in delayed oral health care seeking among this population. The participants had relied on self-care throughout their lifetimes, using either traditional medicines or modern painkillers to relieve toothaches. Fear of dental procedures among children was also described as a barrier to seeking dental health care. CONCLUSIONS: This study found that the lifestyle and traditions of Karen people living in this area influence their oral health care and hygiene activities as well as their health-seeking behaviors. Further research should emphasize how to improve oral health promotion by providing necessary services and health education appropriately to Karen ethnic populations living along the Thai-Myanmar border.

Diarrhoeal disease surveillance in Papua New Guinea: findings and challenges.

Diarrhoeal diseases are among the leading causes of morbidity and mortality in the Western Pacific Region. However, data on the major causes of infectious diarrhoea are limited in many countries within the Region, including Papua New Guinea. In 2013-2014, we conducted surveillance for acute diarrhoeal illness in four provinces in Papua New Guinea. One rural health clinic from each province participated in the surveillance activity. Samples were sent to central laboratories and batch analysed for bacterial and viral gastrointestinal pathogens that are commonly associated with diarrhoea. Across the four sites, the most commonly detected pathogens were Shigella spp., Campylobacter spp. and rotavirus. In this paper, we report the results of the surveillance activity and the challenges that we faced. The lessons learnt may be applicable to other parts of the Region with a similar socioeconomic status.

Spatial Heterogeneity and Temporal Trends in Malaria on the Thai⁻Myanmar Border (2012⁻2017): A Retrospective Observational Study.

Malaria infections remain an important public health problem for the Thai-Myanmar border population, despite a plan for the elimination by the end of 2026 (Thailand) and 2030 (Myanmar). This study aimed to explore spatiotemporal patterns in Plasmodium falciparum and Plasmodium vivax incidence along the Thai-Myanmar border. Malaria cases among Thai citizens in 161 sub-districts in Thailand's Kanchanaburi and Tak Provinces (2012-2017) were analyzed to assess the cluster areas and temporal trends. Based on reported incidence, 65.22% and 40.99% of the areas studied were seen to be at elimination levels for P. falciparum and P. vivax already, respectively. There were two clear clusters of malaria in the region: One in the northern part (Cluster I), and the other in the central part (Cluster II). In Cluster I, the malaria season exhibited two peaks, while there was only one peak seen for Cluster II. Malaria incidence decreased at a faster rate in Cluster I, with 5% and 4% reductions compared with 4% and 3% reductions in P. falciparum and P. vivax incidence per month, respectively, in Cluster II. The decreasing trends reflect the achievements of malaria control efforts on both sides of the Thai-Myanmar border. However, these clusters could act as reservoirs. Perhaps one of the main challenges facing elimination programs in this low transmission setting is maintaining a strong system for early diagnosis and treatment, even when malaria cases are very close to zero, whilst preventing re-importation of cases.

The epidemiological transition in Papua New Guinea: new evidence from verbal autopsy studies.

BACKGROUND: Recent economic growth in Papua New Guinea (PNG) would suggest that the country may be experiencing an epidemiological transition, characterized by a reduction in infectious diseases and a growing burden from non-communicable diseases (NCDs). However, data on cause-specific mortality in PNG are very sparse, and the extent of the transition within the country is poorly understood. METHODS: Mortality surveillance was established in four small populations across PNG: West Hiri in Central Province, Asaro Valley in Eastern Highlands Province, Hides in Hela Province and Karkar Island in Madang Province. Verbal autopsies (VAs) were conducted on all deaths identified, and causes of death were assigned by SmartVA and classified into five broad disease categories: endemic NCDs; emerging NCDs; endemic infections; emerging infections; and injuries. Results from previous PNG VA studies, using different VA methods and spanning the years 1970 to 2001, are also presented here. RESULTS: A total of 868 deaths among adolescents and adults were identified and assigned a cause of death. NCDs made up the majority of all deaths (40.4%), with the endemic NCD of chronic respiratory disease responsible for the largest proportion of deaths (10.5%), followed by the emerging NCD of diabetes (6.2%). Emerging infectious diseases outnumbered endemic infectious diseases (11.9% versus 9.5%). The distribution of causes of death differed across the four sites, with emerging NCDs and emerging infections highest at the site that is most socioeconomically developed, West Hiri. Comparing the 1970-2001 VA series with the present study suggests a large decrease in endemic infections. CONCLUSIONS: Our results indicate immediate priorities for health service planning and for strengthening of vital registration systems, to more usefully serve the needs of health priority setting.

Human population movement and behavioural patterns in malaria hotspots on the Thai-Myanmar border: implications for malaria elimination.

BACKGROUND: Malaria is heterogeneously distributed across landscapes. Human population movement (HPM) could link sub-regions with varying levels of transmission, leading to the persistence of disease even in very low transmission settings. Malaria along the Thai-Myanmar border has been decreasing, but remains heterogeneous. This study aimed to measure HPM, associated predictors of travel, and HPM correlates of self-reported malaria among people living within malaria hotspots. METHODS: 526 individuals from 279 households in two malaria hotspot areas were included in a prospective observational study. A baseline cross-sectional study was conducted at the beginning, recording both individual- and household-level characteristics. Individual movement and travel patterns were repeatedly observed over one dry season month (March) and one wet season month (May). Descriptive statistics, random effects logistic regressions, and logistic regressions were used to describe and determine associations between HPM patterns, individual-, household-factors, and self-reported malaria. RESULTS: Trips were more common in the dry season. Malaria risk was related to the number of days doing outdoor activities in the dry season, especially trips to Myanmar, to forest areas, and overnight trips. Trips to visit forest areas were more common among participants aged 20-39, males, individuals with low income, low education, and especially among individuals with forest-related occupations. Overnight trips were more common among males, and individual with forest-related occupations. Forty-five participants reported having confirmed malaria infection within the last year. The main place of malaria blood examination and treatment was malaria post and malaria clinic, with participants usually waiting for 2-3 days from onset fever to seeking diagnosis. Individuals using bed nets, living in houses with elevated floors, and houses that received indoor residual spraying in the last year were less likely to report malaria infection. CONCLUSION: An understanding of HPM and concurrent malaria dynamics is important for consideration of targeted public health interventions. Furthermore, diagnosis and treatment centres must be capable of quickly diagnosing and treating infections regardless of HPM. Coverage of diagnosis and treatment centres should be broad, maintained in areas bordering malaria hotspots, and available to all febrile individuals.

Correction: Socio-economic status and behavioural and cardiovascular risk factors in Papua New Guinea: A cross-sectional survey.

[This corrects the article DOI: 10.1371/journal.pone.0211068.].

High Efficacy of Primaquine Treatment for Plasmodium vivax in Western Thailand.

Primaquine is the only licensed antimalarial drug that is capable of clearing dormant Plasmodium vivax liver stage parasites. To date, there is no clear evidence of resistance of the liver stage parasite against this drug, because of the difficulty in ascertaining the cause of recurrent infection. We followed 52 Thai P. vivax patients for 9 months after directly observed treatment of 15 mg primaquine daily for 14 days. Blood samples taken at 2-4 weekly intervals were assessed by microscopy and polymerase chain reaction (PCR) for the presence of parasites. Only four of 52 (7.7%) volunteers had recurrent P. vivax infections, all at least 8 weeks after treatment. This demonstrates that primaquine retains a high efficacy in this population. Although a risk of new infections could not be ruled out, parasite genotyping at two polymorphic markers suggested a high probability of late relapsing infections in these volunteers. Continued monitoring of primaquine efficacy in this region is advisable.