Antibodies to Aedes aegypti D7L salivary proteins as a new serological tool to estimate human exposure to Aedes mosquitoes.

Introduction: Aedes spp. are the most prolific mosquito vectors in the world. Found on every continent, they can effectively transmit various arboviruses, including the dengue virus which continues to cause outbreaks worldwide and is spreading into previously non-endemic areas. The lack of widely available dengue vaccines accentuates the importance of targeted vector control strategies to reduce the dengue burden. High-throughput tools to estimate human-mosquito contact and evaluate vector control interventions are lacking. We propose a novel serological tool that allows rapid screening of human cohorts for exposure to potentially infectious mosquitoes. Methods: We tested 563 serum samples from a longitudinal pediatric cohort study previously conducted in Cambodia. Children enrolled in the study were dengue-naive at baseline and were followed biannually for dengue incidence for two years. We used Western blotting and enzyme-linked immunosorbent assays to identify immunogenic Aedes aegypti salivary proteins and measure total anti-Ae. aegypti IgG. Results: We found a correlation (rs=0.86) between IgG responses against AeD7L1 and AeD7L2 recombinant proteins and those to whole salivary gland homogenate. We observed seasonal fluctuations of AeD7L1+2 IgG responses and no cross-reactivity with Culex quinquefasciatus and Anopheles dirus mosquitoes. The baseline median AeD7L1+2 IgG responses for young children were higher in those who developed asymptomatic versus symptomatic dengue. Discussion: The IgG response against AeD7L1+2 recombinant proteins is a highly sensitive and Aedes specific marker of human exposure to Aedes bites that can facilitate standardization of future serosurveys and epidemiological studies by its ability to provide a robust estimation of human-mosquito contact in a high-throughput fashion.

Factors influencing maternal death in Cambodia, Laos, Myanmar, and Vietnam countries: A systematic review.

BACKGROUND: A maternal mortality ratio is a sensitive indicator when comparing the overall maternal health between countries and its very high figure indicates the failure of maternal healthcare efforts. Cambodia, Laos, Myanmar, and Vietnam-CLMV countries are the low-income countries of the South-East Asia region where their maternal mortality ratios are disproportionately high. This systematic review aimed to summarize all possible factors influencing maternal mortality in CLMV countries. METHODS: This systematic review applied "The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Checklist (2020)", Three key phrases: "Maternal Mortality and Health Outcome", "Maternal Healthcare Interventions" and "CLMV Countries" were used for the literature search. 75 full-text papers were systematically selected from three databases (PubMed, Google Scholar and Hinari). Two stages of data analysis were descriptive analysis of the general information of the included papers and qualitative analysis of key findings. RESULTS: Poor family income, illiteracy, low education levels, living in poor households, and agricultural and unskilled manual job types of mothers contributed to insufficient antenatal care. Maternal factors like non-marital status and sex-associated work were highly associated with induced abortions while being rural women, ethnic minorities, poor maternal knowledge and attitudes, certain social and cultural beliefs and husbands' influences directly contributed to the limitations of maternal healthcare services. Maternal factors that made more contributions to poor maternal healthcare outcomes included lower quintiles of wealth index, maternal smoking and drinking behaviours, early and elderly age at marriage, over 35 years pregnancies, unfavourable birth history, gender-based violence experiences, multigravida and higher parity. Higher unmet needs and lower demands for maternal healthcare services occurred among women living far from healthcare facilities. Regarding the maternal healthcare workforce, the quality and number of healthcare providers, the development of healthcare infrastructures and human resource management policy appeared to be arguable. Concerning maternal healthcare service use, the provisions of mobile and outreach maternal healthcare services were inconvenient and limited. CONCLUSION: Low utilization rates were due to several supply-side constraints. The results will advance knowledge about maternal healthcare and mortality and provide a valuable summary to policymakers for developing policies and strategies promoting high-quality maternal healthcare.

Discrimination and violence against women migrant workers in Thailand during the COVID-19 pandemic: A mixed-methods study.

BACKGROUND: Women migrant workers are vulnerable to discrimination and violence, which are significant public health problems. These situations may have been intensified during the COVID-19 pandemic. This study aimed to investigate discrimination against women migrant workers in Thailand during the COVID-19 pandemic and its intersection with their experiences of violence and associated factors. METHODS: A mixed-methods study design was employed to collect data from 572 women migrant workers from Myanmar, Lao People's Democratic Republic, and Cambodia. Face-to-face interviews were conducted with 494 participants using a structured questionnaire for quantitative data, whereas qualitative data was collected through 24 in-depth interviews and focus group discussions with 54 migrant women. Simple and multiple logistic regression and content analysis were employed. RESULTS: This study found that about one in five women migrant workers experienced discrimination during the COVID-19 pandemic. Among those who experienced discrimination, 63.2% had experienced intimate partner violence and 76.4% had experienced non-intimate partner violence in their lifetime. The multivariable analysis revealed that women migrant workers who had experienced any violence (AOR = 2.76, 95% CI = 1.49, 5.12), lost their jobs or income during the pandemic (AOR = 3.99, 95% CI = 2.09, 7.62), and were from Myanmar (AOR = 4.68, 95% CI = 1.79, 12.21) were more likely to have experienced discrimination. CONCLUSION: The results suggest that the intersection of discrimination and violence against women migrant workers in Thailand demands special interest to understand and address the problem. It is recommended that policymakers provide interventions and programs that are inclusive and responsive to the unique needs of women migrants depending on their country of origin and job profile.

Detecting orphanage trafficking and exploitation.

BACKGROUND: There is growing awareness that a proportion of children in orphanages have been recruited or transferred into the facility for a purpose of exploitation and/or profit. These children are often falsely presented as orphans to evoke sympathy and solicit funding. This process is known as orphanage trafficking. Although orphanage trafficking can be prosecuted under legal frameworks in some jurisdictions, including Cambodia, there have been limited prosecutions to date. One factor that likely contributes to a lack of prosecution is poor detection, yet the indicators of orphanage trafficking have not been considered by extant research. OBJECTIVE: The current study was conducted as a first step towards providing evidence-based indicators of orphanage trafficking. PARTICIPANTS AND SETTING: Professionals who had identified or responded to cases of orphanage-based exploitation in Cambodia were interviewed. Participants included criminal justice professionals, investigators from civil society organisations, and child protection social workers. METHODS: Professionals' perspectives on how to identify orphanage trafficking were explored via in-depth interviews, and the data were analysed via thematic analysis. RESULTS: The analysis revealed a distinct set of indicators that may be used to detect orphanage trafficking, including the operation of an unauthorised facility, orphanage tourism and volunteering, and an overt focus on fundraising. CONCLUSION: The indicators revealed in this study point to the need for an effective and thorough monitoring system for orphanages, as well as adequate education and training of relevant personnel to aid in the detection of orphanage trafficking.

Prevalence, Correlates, and Trends of Intimate Partner Violence Against Women in Cambodia: Findings From 2014 and 2021-22 Cross-Sectional Demographic and Health Surveys.

Intimate partner violence (IPV) is globally endemic and a gross violation of human rights, in addition to abuse of intimacy by some men against their female intimate partners. Based on literature review, attitudinal, socio-demographic, and experiential attributes of 15 to 49 year old ever partnered women in the heterosexual relationships were identified. This study used the anonymized 2020-21Cambodia Demographic and Health Survey (CDHS) data to compute the IPV prevalence and its correlates, in addition to computing the changes in IPV prevalence at the urban, rural, and at the national levels using data from the 2014 CDHS. Identified attitudinal, socio-demographic, and experiential attributes were used in the bivariate and multivariable analysis. Simple and multiple logistic regression models were used for computing the bivariate and multivariate associations with IPV; additionally, trend analysis was done to compute changes in IPV prevalence between the 2 surveys. Lifetime prevalence of IPV was 20.70%, while the most common subtype was emotional IPV at 18.70%. Ten out of 12 correlates studied were found to be statistically significantly associated with IPV in the bivariate analysis. These were added in the multivariable model and 7 were found to be statistically significantly associated with IPV. Which included educational attainment of women and their intimate partners, number of living children, women's IPV acceptance, male partner's alcohol use, knowledge of physical beating of mother by one's father, and controlling behavior exercised by partner. During the intervening period between the 2 CDHSs, IPV and its subtypes were decreased in both urban and rural areas, as well as nationally. IPV decrease between the 2 DHSs and lower IPV rates in 2021-22 augur well for the health and human rights of Cambodian women. However, the ultimate target of eliminating IPV against women, will require measures that ensure economic and gender empowerment, and gender equality.

Adherence and acceptability of multiple micronutrient supplementation during pregnancy: Study protocol for a cluster-randomized non-inferiority trial in Cambodia.

BACKGROUND: Iron and folic acid (IFA) supplements are currently provided to Cambodian women during pregnancy. However, recent research has found benefits of a multiple micronutrient supplement (MMS) over just IFA alone on several outcomes of perinatal and infant health. The Ministry of Health in Cambodia has proposed a transition from IFA to MMS but to effectively guide this transition requires implementation research on the acceptability and adherence to MMS (over IFA). METHODS: This non-inferiority trial aims to assess the adherence and acceptability of IFA (60 mg elemental iron and 400 µg folic acid) compared to MMS (standard UNIMMAP formulation including 15 micronutrients) during antenatal care in Cambodia. A prospective cohort of 1545 pregnant women will be assigned to one of three trial arms: (1) IFA for 90 days [IFA-90]; (2) MMS for 180 days with two distributions of 90-count tablet bottles [MMS-90]; or (3) MMS for 180 days with one 180-count tablet bottle [MMS-180]. Each arm will enroll 515 women across 48 health centers (clusters) in Kampong Thom Province in Cambodia. The primary outcome is the non-inferiority of adherence rates of MMS-180 compared to IFA-90, as assessed by tablet counts. Mixed-effects logistic and linear regression models will be used to estimate the difference in the adherence rate between the two groups, with an 'a priori' determined non-inferiority margin of 15%. Acceptability of MMS and IFA will be measured using a quantitative survey conducted with enrolled pregnant women at 30-day, 90-day, and 180-day time-points. DISCUSSION: Findings from this study will guide an effective and feasible MMS scale-up strategy for Cambodia. Additionally, the findings will be shared globally with other stakeholders planning to scale up MMS in other countries. TRIAL REGISTRATION: NCT05867836 ( ClinicalTrials.gov , registered May 18, 2023).

Bayesian modeling of post-vaccination serological data suggests that yearly vaccination of dog aged <2 years old is efficient to stop rabies circulation in Cambodia.

Rabies control remains challenging in low and middle-income countries, mostly due to lack of financial resources, rapid turnover of dog populations and poor accessibility to dogs. Rabies is endemic in Cambodia, where no national rabies vaccination program is implemented. The objective of this study was to assess the short and long-term vaccination-induced immunity in Cambodian dogs under field conditions, and to propose optimized vaccination strategies. A cohort of 351 dogs was followed at regular time points following primary vaccination only (PV) or PV plus single booster (BV). Fluorescent antibody virus neutralization test (FAVNT) was implemented to determine the neutralizing antibody titer against rabies and an individual titer ≥0·5 IU/mL indicated protection. Bayesian modeling was used to evaluate the individual duration of protection against rabies and the efficacy of two different vaccination strategies. Overall, 61% of dogs had a protective immunity one year after PV. In dogs receiving a BV, this protective immunity remained for up to one year after the BV in 95% of dogs. According to the best Bayesian model, a PV conferred a protective immunity in 82% of dogs (95% CI: 75-91%) for a mean duration of 4.7 years, and BV induced a lifelong protective immunity. Annual PV of dogs less than one year old and systematic BV solely of dogs vaccinated the year before would allow to achieve the 70% World Health Organization recommended threshold to control rabies circulation in a dog population in three to five years of implementation depending on dog population dynamics. This vaccination strategy would save up to about a third of vaccine doses, reducing cost and time efforts of mass dog vaccination campaigns. These results can contribute to optimize rabies control measures in Cambodia moving towards the global goal of ending human death from dog-mediated rabies by 2030.

Genomic insights into anthropozoonotic tuberculosis in captive sun bears (Helarctos malayanus) and an Asiatic black bear (Ursus thibetanus) in Cambodia.

Contact between humans and wildlife presents a risk for both zoonotic and anthropozoonotic disease transmission. In this study we report the detection of human strains of Mycobacterium tuberculosis in sun bears and an Asiatic black bear in a wildlife rescue centre in Cambodia, confirming for the first time the susceptibility of these bear species to tuberculosis when in close contact with humans. After genotyping revealed two different strains of M. tuberculosis from cases occurring between 2009 and 2019, 100 isolates from 30 sun bear cases, a single Asiatic black bear case, and a human case were subjected to whole genome sequencing. We combined single nucleotide polymorphism analysis and exploration of mixed base calls with epidemiological data to indicate the evolution of each outbreak. Our results confirmed two concurrent yet separate tuberculosis outbreaks and established a likely transmission route in one outbreak where the human case acted as an intermediatory between bear cases. In both outbreaks, we observed high rates of transmission and progression to active disease, suggesting that sun bears are highly susceptible to tuberculosis if exposed under these conditions. Overall, our findings highlight the risk of bi-directional transmission of tuberculosis between humans and captive bears in high human tuberculosis burden regions, with implied considerations for veterinary and public health. We also demonstrate the use of standard genomic approaches to better understand disease outbreaks in captive wildlife settings and to inform control and prevention measures.

Dermatophytes and skin dermatophytoses in Southeast Asia-First epidemiological survey from Cambodia.

BACKGROUND: Dermatomycoses count to the most frequent dermatoses in Cambodia. OBJECTIVES: The aim of this survey was to investigate the occurrence of dermatophytes in this Southeast Asian country. METHODS: From June 2017 to July 2018, skin scrapings were taken from 67 patients with superficial dermatophytosis for mycological diagnostics. Identification of dermatophytes was confirmed by sequencing of the 'internal transcribed spacer'-(ITS) region of the rDNA, and the gene of the Translation Elongation Factor (TEF)-1α. RESULTS: Patients were suffering from tinea corporis and tinea inguinalis/cruris 42/67 (63%), tinea capitis/faciei 14/67 (21%), tinea corporis/capitis/faciei 6/67 (9%), tinea manuum/pedis 2/67 (3%), tinea pedis 2/67 (3%) and tinea manuum 1/67 (1%). Both, by culture and/or PCR, a dermatophyte was detected in 52 (78%) out of 67 samples. Culture positive were 42 (81%) of 52, PCR positive were 50 (96%). The following dermatophytes were found: Trichophyton (T.) rubrum, 36/52 strains (69%, 29 by culture), T. mentagrophytes/T. interdigitale (TM/TI) 9/52 (17%, six by culture) and Microsporum (M.) canis 5/52 strains (10%, by culture). One strain of Nannizzia (N.) incurvata 1/52 (2%) and N. nana 1/52 (2%) was isolated. Based on sequencing, we demonstrated that two T. mentagrophytes strains out of the nine TM/TI represented the new ITS genotype XXV Cambodia. We found one T. mentagrophytes strain genotype VIII (now, reclassified as T. indotineae). This isolate was terbinafine resistant, and it exhibited the amino acid substitution Phe397Leu in the squalene epoxidase. Three strains of T. interdigitale genotype II* were isolated. CONCLUSION: This is the first survey on epidemiology of dermatophytes in Cambodia. Currently, T. rubrum represents the most frequent species in Cambodia. One Indian strain genotype VIII T. mentagrophytes was found. A highlight was the first description of the new T. mentagrophytes genotype XXV Cambodia.

Comparing malaria risk exposure in rural Cambodia population using GPS tracking and questionnaires.

BACKGROUND: The Great Mekong Subregion has attained a major decline in malaria cases and fatalities over the last years, but residual transmission hotspots remain, supposedly fueled by forest workers and migrant populations. This study aimed to: (i) characterize the fine-scale mobility of forest-goers and understand links between their daily movement patterns and malaria transmission, using parasites detection via real time polymerase chain reaction (RT PCR) and the individual exposure to Anopheles bites by quantification of anti-Anopheles saliva antibodies via enzyme-linked immunosorbent assay; (ii) assess the concordance of questionnaires and Global Positioning System (GPS) data loggers for measuring mobility. METHODS: Two 28 day follow-ups during dry and rainy seasons, including a GPS tracking, questionnaires and health examinations, were performed on male forest goers representing the population at highest risk of infection. Their time spent in different land use categories and demographic data were analyzed in order to understand the risk factors driving malaria in the study area. RESULTS: Malaria risk varied with village forest cover and at a resolution of only a few kilometers: participants from villages outside the forest had the highest malaria prevalence compared to participants from forest fringe's villages. The time spent in a specific environment did not modulate the risk of malaria, in particular the time spent in forest was not associated with a higher probability to detect malaria among forest-goers. The levels of antibody response to Anopheles salivary peptide among participants were significantly higher during the rainy season, in accordance with Anopheles mosquito density variation, but was not affected by sociodemographic and mobility factors. The agreement between GPS and self-reported data was only 61.9% in reporting each kind of visited environment. CONCLUSIONS: In a context of residual malaria transmission which was mainly depicted by P. vivax asymptomatic infections, the implementation of questionnaires, GPS data-loggers and quantification of anti-saliva Anopheles antibodies on the high-risk group were not powerful enough to detect malaria risk factors associated with different mobility behaviours or time spent in various environments. The joint implementation of GPS trackers and questionnaires allowed to highlight the limitations of both methodologies and the benefits of using them together. New detection and follow-up strategies are still called for.

New species and new records of chigger mites (Acariformes, Trombiculidae) from Cambodia.

Two new chigger species, Leptotrombidium mondulkiri sp. nov. and Walchia keoseima sp. nov., and one new subspecies, Leptotrombidium pilosum cambodiensis subsp. nov., are described from Cambodia. Three species, Walchia lupella (Traub and Evans, 1957), W. micropelta (Traub and Evans, 1957), and W. kritochaeta (Traub and Evans, 1957), are for the first time reported from the country. A redescription of W. lupella is given based on new materials from Cambodia and Thailand.

Fairy moths of the genus Nemophora Hoffmannsegg, 1798 (Lepidoptera: Adelidae) from Myanmar, Thailand, Laos, Cambodia and Vietnam.

This study provides a comprehensive account of 40 species (52 valid names and one preoccupied name) of the genus Nemophora Hoffmannsegg, 1798 described or recorded from Myanmar, Thailand, Laos, Cambodia and Vietnam. A key to the species based on external characters and on male genitalia is provided; 14 new species are described: N. auricapitella Kozlov, sp. nov., N. chalcoptera Kozlov, sp. nov., N. karsholti Kozlov, sp. nov., N. kuznetzovi Kozlov, sp. nov., N. meyi Kozlov, sp. nov., N. nielseni Kozlov, sp. nov., N. nieukerkeni Kozlov, sp. nov., N. nigripunctella Kozlov, sp. nov., N. punctifasciella Kozlov, sp. nov., N. rubicunda Kozlov, sp. nov., N. szabokyi Kozlov, sp. nov., N. thailandensis Kozlov, sp. nov., N. vietnamensis Kozlov, sp. nov. and N. yeni Kozlov, sp. nov. Lectotypes are designated for four species, including one junior synonym: Nemotois diplophragma Meyrick, 1938, Nemotois sinicella Walker, 1863, Nemotois cleodoxa Meyrick, 1922 and Adela satrapodes Meyrick, 1894. Eight new synonyms for four species are proposed: Nemophora badagongshana Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora aurifera (Butler, 1881); Nemotois chrysocharis Caradja, 1938, syn. nov. of Nemophora sinicella (Walker, 1863); Nemotois diplophragma Meyrick, 1938, syn. nov. of Nemophora melichlorias (Meyrick, 1907); Nemophora basalistriata Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora melichlorias (Meyrick, 1907); Nemotois limenites Meyrick, 1914, syn. nov. of Nemophora aurifera (Butler, 1881); Nemophora quadrata Liao, Hirowatari & Huang in Liao, Hirowatari, Yagi, Wang, Wang & Huang, 2023, syn. nov. of Nemophora aurifera (Butler, 1881); Nemotois rubrofascia formosicola Matsumura, 1931, syn. nov. of Nemophora sakaii (Matsumura, 1931); Nemotois servata Meyrick in Caradja, 1925, syn. nov. of Nemophora aurifera (Butler, 1881). Four new combinationsare introduced: Nemophora aglaospila (Meyrick, 1928), comb. nov.; Nemophora cleodoxa (Meyrick, 1922), comb. nov.; Nemophora melichlorias (Meyrick, 1907), comb. nov.; and Nemophora sinicella (Walker, 1863), comb. nov. Of 40 species considered, 16 were recorded in Myanmar, 21 in Thailand, 4 in Laos, 4 in Cambodia and 13 in Vietnam.

Defining the hidden burden of disease in rural communities in Bangladesh, Cambodia and Thailand: a cross-sectional household health survey protocol.

INTRODUCTION: In low-income and middle-income countries in Southeast Asia, the burden of diseases among rural population remains poorly understood, posing a challenge for effective healthcare prioritisation and resource allocation. Addressing this knowledge gap, the South and Southeast Asia Community-based Trials Network (SEACTN) will undertake a survey that aims to determine the prevalence of a wide range of non-communicable and communicable diseases, as one of the key initiatives of its first project-the Rural Febrile Illness project (RFI). This survey, alongside other RFI studies that explore fever aetiology, leading causes of mortality, and establishing village and health facility maps and profiles, will provide an updated epidemiological background of the rural areas where the network is operational. METHODS AND ANALYSIS: During 2022-2023, a cross-sectional household survey will be conducted across three SEACTN sites in Bangladesh, Cambodia and Thailand. Using a two-stage cluster-sampling approach, we will employ a probability-proportional-to-size sample method for village, and a simple random sample for household, selection, enrolling all members from the selected households. Approximately 1500 participants will be enrolled per country. Participants will undergo questionnaire interview, physical examination and haemoglobin point-of-care testing. Blood samples will be collected and sent to central laboratories to test for chronic and acute infections, and biomarkers associated with cardiovascular disease, and diabetes. Prevalences will be presented as an overall estimate by country, and stratified and compared across sites and participants' sociodemographic characteristics. Associations between disease status, risk factors and other characteristics will be explored. ETHICS AND DISSEMINATION: This study protocol has been approved by the Oxford Tropical Research Ethics Committee, National Research Ethics Committee of Bangladesh Medical Research Council, the Cambodian National Ethics Committee for Health Research, the Chiang Rai Provincial Public Health Research Ethical Committee. The results will be disseminated via the local health authorities and partners, peer-reviewed journals and conference presentations. TRIAL REGISTRATION NUMBER: NCT05389540.

Using serological diagnostics to characterize remaining high-incidence pockets of malaria in forest-fringe Cambodia.

BACKGROUND: Over the last decades, the number of malaria cases has drastically reduced in Cambodia. As the overall prevalence of malaria in Cambodia declines, residual malaria transmission becomes increasingly fragmented over smaller remote regions. The aim of this study was to get an insight into the burden and epidemiological parameters of Plasmodium infections on the forest-fringe of Cambodia. METHODS: 950 participants were recruited in the province of Mondulkiri in Cambodia and followed up from 2018 to 2020. Whole-blood samples were processed for Plasmodium spp. identification by PCR as well as for a serological immunoassay. A risk factor analysis was conducted for Plasmodium vivax PCR-detected infections throughout the study, and for P. vivax seropositivity at baseline. To evaluate the predictive effect of seropositivity at baseline on subsequent PCR-positivity, an analysis of P. vivax infection-free survival time stratified by serological status at baseline was performed. RESULTS: Living inside the forest significantly increased the odds of P. vivax PCR-positivity by a factor of 18.3 (95% C.I. 7.7-43.5). Being a male adult was also a significant predictor of PCR-positivity. Similar risk profiles were identified for P. vivax seropositivity. The survival analysis showed that serological status at baseline significantly correlated with subsequent infection. Serology is most informative outside of the forest, where 94.0% (95% C.I. 90.7-97.4%) of seronegative individuals survived infection-free, compared to 32.4% (95% C.I.: 22.6-46.6%) of seropositive individuals. CONCLUSION: This study justifies the need for serological diagnostic assays to target interventions in this region, particularly in demographic groups where a lot of risk heterogeneity persists, such as outside of the forest.

A 12-year follow up survey of childhood blindness at schools for the blind in Cambodia.

BACKGROUND: Cambodia is a low-income country in South East Asia with a population of 15.5 million people of whom 4.9 million (38%) are under the age of 16. The causes of childhood blindness in Cambodia have not been investigated since the first survey of schools for the blind done in 2009 by our group. Given the large demographic and economic shifts in Cambodia since 2009 it is important to determine if these causes have changed in order to ensure intervention programmes are appropriately targeted. The purpose of the present study is to investigate the prevalence of causes of childhood blindness at schools for the blind in Cambodia. METHODS: Students between the ages of 5 and 16 years who were attending schools for the blind in Cambodia were examined by a consultant paediatric ophthalmologist and had clinical photographs taken. Distance visual acuity was measured using a logMAR tumbling E chart and the WHO definitions of blindness and severe visual impairment were used. The examining ophthalmologist recorded the anatomical site and aetiology of vision loss using the WHO Prevention of Blindness eye examination record for children. Collected data were compared to a previous survey from 2009. RESULTS: Data from 73 students were included for analysis. The most common anatomical location of abnormality causing vision loss was the cornea (n = 20, 33.9%) followed by the lens and retina (n = 11, 18.64% each). Hereditary factors (n = 29, 49.15%) and childhood diseases (n = 27, 45.76%) were the most common aetiological causes of childhood blindness. The majority (71.19%) of childhood blindness was avoidable. The present study did not demonstrate 0a significant difference in the causes of childhood blindness compared to 2009. CONCLUSIONS: Corneal pathologies continue to represent the most common cause of vision loss amongst the surveyed population and the majority of causes of childhood blindness continue to be avoidable. These findings will facilitate the development of evidence-based targeted interventional programmes in Cambodia.

Metagenomic insight into the pathogenic-related characteristics and resistome profiles within microbiome residing on the Angkor sandstone monuments in Cambodia.

To reveal the characteristics of indigenous microbiome including the pathogenic-related ones on Angkor monuments in Cambodia and the distribution pattern of resistome at different locations, several sites, namely Angkor Wat, Bayon of Angkor Thom, and Prasat Preah Vihear with different exposure levels to tourists were selected to conduct the metagenomic analysis in this study. The general characteristics of the microbiome on these monuments were revealed, and the association between the environmental geo-ecological feature and the indigenous microbiome was delineated. The most common microbial groups included 6 phyla, namely Acidobacteria, Actinobacteria, Gemmatimonadetes, Nitrospirae, Proteobacteria and Verrucomicrobia on the monuments, but Firmicutes and Chlamydiae were the most dominant phyla found in bats droppings. The taxonomic family of Chitinophagaceae could serve as a signature microbial group for Preah Vihear, the less visited site. More importantly, the pathogenic-related characteristics of the microbiome residing on Angkor monuments were uncovered. A set of specific antibiotic resistance genes (ARGs) with cross-niches dispersal capacity (between the environmental microbiome and the microbiome within warm blood fauna) was identified to be high by the source tracking analysis based on ARGs profile varies in this study. Among the 10 ARG-types detected in this study, 6 of them are confined to resistance mechanism of antibiotic efflux-pump. The findings of this study provide new a new direction on public health management and implication globally at archaeological sites for tourism.

Sugar-Sweetened Beverages, Foods of Low Nutritional Value, and Child Undernutrition in Cambodia.

Child undernutrition persists in Cambodia despite recent progress. As Cambodia undergoes a shift in dietary consumption that coincides with economic, demographic, and epidemiologic changes, there is risk of ultra-processed foods and sugar-sweetened beverages displacing nutrient-dense foods during the critical period of infant growth in the first 24 months. The aim of this study was to assess the introduction and intake of foods of low nutritional value and sugar-sweetened beverages and their association with undernutrition among children 24 months of age in rural and semi-urban Cambodia. Cross-sectional analyses of a 24-h dietary recall from a sample (n = 377) of 24-month-olds found that the majority of infants had been introduced to packaged salty snacks and sweets by 12 months of age and to sugar-sweetened beverages by 15 months. By 24 months of age, 78% of children had consumed foods of low nutritional value and 57% consumed a sugar-sweetened beverage on the previous day. Multivariate logistic regression analyses demonstrated that infant intake of a flavored sugary drink on the previous day was associated with over two times the odds of both stunting and wasting, and consumption of packaged sweets on the previous day was associated with over two times the odds of wasting, but no association was found with stunting. These findings underscore the need to improve educational and policy interventions to support healthy feeding practices for infants and young children.

Simplified Criteria to Assess Long-Term Antiviral Treatment Indication in Chronic HBV-Infected Pregnant Women in Cambodia.

Pregnant women identified to carry hepatitis B surface antigen (HBsAg) should be linked to care for the determination of the need for long-term antiviral therapy (LTT). We assessed the performance of simplified criteria, free from HBV DNA quantification, to select women eligible for LTT using different international guidelines as a reference. A retrospective analysis of HBV-infected pregnant women enrolled in the phase 4 ANRS TA-PROHM study was conducted in Cambodia. Sensitivity, specificity, and AUROC were computed to compare three simplified criteria (TREAT-B, HBcrAg/ALT, and TA-PROHM) with the American (AASLD) and European (EASL) guidelines as a reference. An additional assessment was performed at 6 months postpartum. Of 651 HBsAg-positive women, 209 (32%) received peripartum antiviral prophylaxis using tenofovir disoproxil fumarate (TDF). During pregnancy, 9% and 12% of women were eligible for LTT according to AASLD and EASL guidelines, respectively; 21% and 24% of women were eligible for prophylactic TDF and 2% and 5% in those ineligible (p < 0.001). Using the AASLD guidelines, the AUROC of TREAT-B, HBcrAg/ALT, and TA-PROHM scores were 0.88 (95%CI, 0.85-0.90), 0.90 (95%CI, 0.87-0.92), and 0.76 (95%CI, 0.73-0.80), respectively. Using the EASL guidelines, the AUROCs were lower: 0.73 (95%CI, 0.69-0.76), 0.76 (95%CI, 0.73-0.80), and 0.71 (95%CI, 0.67-0.74), respectively. Among those ineligible for prophylactic TDF, only 2% to 6% present an indication for LTT at 24 weeks postpartum. Few pregnant women are eligible for LTT, and the use of simplified criteria could represent an efficient triage option in decentralized areas to identify those negative for whom there is no urgent indication for LTT and focus on those positive for whom other exams must be conducted to confirm LTT indication.

High Prevalence of Echinostoma mekongi Infection in Schoolchildren and Adults, Kandal Province, Cambodia.

A high prevalence of Echinostoma mekongi infection (13.9%; 260/1,876) was found among schoolchildren and adults in Kandal Province, Cambodia, by fecal examination, worm expulsion, and molecular analysis of cox1 and nd1 genes. The source of infection was consumption of Pila sp. snails, a finding confirmed morphologically and molecularly.

Radical cure for Plasmodium vivax malaria after G6PD qualitative testing in four provinces in Cambodia, results from Phase I implementation.

BACKGROUND: Cambodia aims to eliminate all forms of malaria by 2025. In 2020, 90% of all malaria cases were Plasmodium vivax. Thus, preventing P. vivax and relapse malaria is a top priority for elimination. 14-day primaquine, a World Health Organization-recommended radical cure treatment regimen, specifically targets dormant hypnozoites in the liver to prevent relapse. Cambodia introduced P. vivax radical cure with primaquine after glucose-6-phosphate dehydrogenase (G6PD) qualitative testing in 2019. This paper presents Cambodia's radical cure Phase I implementation results and assesses the safety, effectiveness, and feasibility of the programme prior to nationwide scale up. METHODS: Phase I implementation was carried out in 88 select health facilities (HFs) across four provinces. Males over 20kgs with confirmed P. vivax or mixed (P. vivax and Plasmodium falciparum) infections were enrolled. A descriptive analysis evaluated the following: successful referral to health facilities, G6PD testing results, and self-reported 14-day treatment adherence. P. vivax incidence was compared before and after radical cure rollout and a controlled interrupted time series analysis compared the estimated relapse rate between implementation and non-implementation provinces before and after radical cure. RESULTS: In the 4 provinces from November 2019 to December 2020, 3,239 P. vivax/mixed infections were reported, 1,282 patients underwent G6PD deficiency testing, and 959 patients received radical cure, achieving 29.6% radical cure coverage among all P. vivax/mixed cases and 98.8% coverage among G6PD normal patients. Among those who initiated radical cure, 747 patients (78%) completed treatment. Six patients reported side effects. In implementation provinces, an average 31.8 relapse cases per month were estimated signaling a 90% (286 cases) reduction in relapse compared to what would be expected if radical cure was not implemented. CONCLUSIONS: Plasmodium vivax radical cure is a crucial tool for malaria elimination in Cambodia. The high coverage of radical cure initiation and adherence among G6PD normal patients demonstrated the high feasibility of providing radical cure at point of care in Cambodia. Incomplete referral from community to HFs and limited capacity of HF staff to conduct G6PD testing in high burden areas led to lower coverage of G6PD testing. Phase I implementation informed approaches to improve referral completion and patient adherence during the nationwide expansion of radical cure in 2021.