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Background: Urban Kaohsiung City (KC), in southern Taiwan, has experienced annual dengue epidemics for decades despite considerable vector control efforts. Substantial research has been undertaken to characterize Aedes aegypti breeding habitats, but no systematic assessment has been completed for Aedes albopictus present in KC., Methods: A cross-sectional survey was conducted from 2013 to 2015 in a predefined area of KC. Each identified container was characterised by season, location, ownership, function and number of juvenile A. aegypti. Negative binomial hurdle analyses were applied to evaluate the association between the number of juvenile A. albopictus and the characteristics of each identified container., Results: For all containers, high numbers of A. albopictus were significantly predicted by containers identified during the wet season (vs dry), located on government (vs private) property and classified as a discarded item (vs water storage). For outdoor containers, more A. albopictus were significantly predicted by wet season (vs dry) and discarded item (vs container in use)., Conclusions: In order to improve dengue prevention in KC, we propose that vector control efforts be expanded to include A. albopictus through an increased focus during the wet season on discarded containers that are located outdoors and on government property., (© The Author(s) 2019. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Evidence from high income countries (HICs) suggests that individuals who present to hospital after self-harm are an important target for suicide prevention, but evidence from low and middle-income countries (LMICs) is lacking. We aimed to investigate the risk of repeat self-harm and suicide, and factors associated with these outcomes, in a large cohort of patients presenting to hospital with self-harm in rural Sri Lanka., Methods: In this cohort study, hospital presentations for self-harm at 13 hospitals in a rural area of North Central Province (population 224 000), Sri Lanka, were followed up with a self-harm surveillance system, established as part of a community randomised trial, and based on data from all hospitals, coroners, and police stations in the study area. We estimated the risk of repeat non-fatal and fatal self-harm and risk factors for repetition with Kaplan-Meier methods and Cox proportional hazard models. Sociodemographic (age, sex, and socioeconomic position) and clinical (past self-harm and method of self-harm) characteristics investigated were drawn from a household survey in the study area and data recorded at the time of index hospital presentation. We included all individuals who had complete data for all variables in the study in our primary analysis., Outcomes: Between July 29, 2011, and May 12, 2016, we detected 3073 episodes of self-harm (fatal and non-fatal) in our surveillance system, of which 2532 (82·3%) were linked back to an individual in the baseline survey. After exclusion of 145 ineligible episodes, we analysed 2259 index episodes of self-harm. By use of survival models, the estimated risk of repeat self-harm (12 months: 3· 1%, 95% CI 2·4-3·9; 24 months: 5·2%, 4·3-6·4) and suicide (12 months: 0·6%, 0·4-1·1; 24 months: 0·8%, 0·5-1·3) in our study was considerably lower than that in HICs. A higher risk of repeat self-harm was observed in men than in women (fatal and non-fatal; hazard ratio 2·0, 95% CI 1·3-3·2; p=0·0021), in individuals aged 56 years and older compared with those aged 10-25 years (fatal; 16·1, 4·3-59·9; p=0·0027), and those who used methods other than poisoning in their index presentation (fatal and non-fatal; 3·9, 2·0-7·6; p=0·00027). We found no evidence of increased risk of repeat self-harm or suicide in those with a history of self-harm before the index episode., Interpretation: Although people who self-harm are an important high-risk group, focusing suicide prevention efforts on those who self-harm might be somewhat less important in LMICs compared with HICs given the low risk of repeat self-harm and subsequent suicide death. Strategies that focus on other risk factors for suicide might be more effective in reducing suicide deaths in LMICs in south Asia. A better understanding of the low incidence of repeat self-harm is also needed, as this could contribute to prevention strategies in nations with a higher incidence of repetition and subsequent suicide death., Funding: Wellcome Trust., (Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: Irresponsible media reporting may influence suicidal behavior. Adherence to guidelines for responsible reporting of suicide has not been examined in Sri Lanka in recent times., Aims: To examine the quality of reporting on self-harm and suicide in Sri Lankan newspapers and compare the quality between Sinhala and English newspapers., Method: From December 1, 2014 to January 31, 2015, 407 editions of newspapers were screened. Reporting quality was measured using the PRINTQUAL tool., Results: We identified 68 articles covering an episode of self-harm or suicide (42 Sinhala and 26 English). The majority of articles were noncompliant with guidelines for sensitive reporting. Indicators of noncompliance included that newspaper articles frequently reported method in the headline (53%), included detailed characteristics of the individual (100%), used insensitive language (58% of English articles), and attributed a single-factor cause to the self-harm (52%). No information about help-seeking was included., Limitations: The study involved a relatively short period of data collection. Including social media, Tamil language newspapers, and online publications would have provided additional understanding of reporting practices., Conclusion: The majority of Sri Lankan newspapers did not follow the principles of good reporting, indicating a need for further training of journalists.

Background: In South Asia, up to one in five individuals who use pesticides for self-harm purchase them immediately prior to the event., Aims: From reviewing the literature we proposed four interventions: (a) farmer identification cards (ID); (b) prescriptions; (c) cooling-off periods; and (d) training pesticide vendors. We aimed to identify the most promising intervention., Method: The study was conducted in Sri Lanka. We mapped stakeholders' interest and power in relation to each intervention, and followed this by a ranking exercise. Seven focus group discussions (FGDs) were conducted to assess facilitators and barriers to implementation., Results: Vendor training was the most supported intervention, being ranked first by the stakeholders. The participants in the FGDs strongly supported training of vendors as it was seen to be easy to implement and was considered more convenient. Farmer IDs, prescriptions, and cooling-off periods were thought to have more barriers than facilitators and they were strongly opposed by end users (farmers and vendors), who would potentially block their implementation., Limitations: Cost considerations for implementing the proposed intervention were not considered., Conclusion: Training vendors might be the most appropriate intervention to restrict sales of pesticides to people at risk of suicidal behavior. This requires field testing.

Background: Pesticide self-poisoning accounts for 14-20% of suicides worldwide. Regulation aimed at restricting access to pesticides or banning highly hazardous pesticides is one approach to reducing these deaths. We systematically reviewed the evidence of the effectiveness of pesticide regulation in reducing the incidence of pesticide suicides and overall suicides., Methods: We did a systematic review of the international evidence. We searched MEDLINE, PsycINFO, and Embase for studies published between Jan 1, 1960, and Dec 31, 2016, which investigated the effect of national or regional bans, and sales or import restrictions, on the availability of one or more pesticides and the incidence of suicide in different countries. We excluded other interventions aimed at limiting community access to pesticides. We extracted data from studies presenting pesticide suicide data and overall suicide data from before and after national sales restrictions. Two reviewers independently assessed papers for inclusion, extracted data, and assessed risk of bias. We undertook a narrative synthesis of the data in each report, and where data were available for the years before and after a ban, we pooled data for the 3 years before and the 3 years after to obtain a crude estimate of the effect of the ban. This study is registered through PROSPERO, number CRD42017053329., Findings: We identified 27 studies undertaken in 16 countries-five low-income or middle-income countries (Bangladesh, Colombia, India, Jordan and Sri Lanka), and 11 high-income countries (Denmark, Finland, Germany, Greece, Hungary, Ireland, Japan, South Korea, Taiwan, UK, and USA). Assessments largely focused on national bans of specific pesticides (12 studies of bans in six countries-Jordan, Sri Lanka, Bangladesh, Greece [Crete], South Korea, and Taiwan) or sales restrictions (eight studies of restrictions in five countries- India, Denmark, Ireland, the UK and the USA). Only five studies used optimum analytical methods. National bans on commonly ingested pesticides in five of the six countries studied, including four studies using optimum analytical methods, were followed by reductions in pesticide suicides and, in three of these countries, falls in overall suicide mortality. Greece was the only country studied that did not show a decrease in pesticide suicide following a ban. There were no high-quality studies of restricting sales to people for occupational uses; four of the seven studies (in three of the five countries studied-India, Denmark, and the USA) showed sales restrictions were followed by decreases in pesticide suicides; one of the two studies investigating trends in overall suicide mortality reported a fall in deaths in Denmark, but there were also decreases in suicide deaths from other methods., Interpretation: National bans on highly hazardous pesticides, which are commonly ingested in acts of self-poisoning, seem to be effective in reducing pesticide-specific and overall suicide rates. Evidence is less consistent for sales restrictions. A worldwide ban on the use of highly hazardous pesticides is likely to prevent tens of thousands of deaths every year., Funding: None., (Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

In 15% to 20% of self-poisoning cases, the pesticides used are purchased from shops just prior to ingestion. We explored how pesticide vendors interacted with customers at risk of self-poisoning to identify interventions to prevent such poisonings. Two strategies were specifically discussed: selling pesticides only to farmers bearing identity cards or customers bearing pesticide 'prescriptions'. Vendors reported refusing to sell pesticides to people thought to be at risk of self-poisoning, but acknowledged the difficulty of distinguishing them from legitimate customers; vendors also stated they did want to help to improve identification of such customers. The community did not blame vendors when pesticides used for self-poison were purchased from their shops. Vendors have already taken steps to restrict access, including selling low toxic products, counselling and asking customer to return the next day. However, there was little support for the proposed interventions of 'identity cards' and 'prescriptions'. Novel public health approaches are required to complement this approach.

Background: In Vietnam, initiatives have been started aimed at increasing the practice of handwashing with soap (HWWS) among primary schoolchildren. However, compliance remains low., Objective: This study aims to investigate responses to a teacher-centred participatory HWWS intervention in a multi-ethnic population of primary schoolchildren in northern rural Vietnam., Design: This study was implemented in two phases: a formative research project over 5 months (July-November 2008) and an action research project with a school-based HWWS intervention study in two rural communes during 5 months (May, September-December 2010). Based upon knowledge from the formative research in 2008, schoolteachers from four selected schools in the study communes actively participated in designing and implementing a HWWS intervention. Qualitative data was collected during the intervention to evaluate the responses and reaction to the intervention of teachers, children and parents. This included semi-structured interviews with children (15), and their parents (15), focus group discussions (FGDs) with schoolchildren (32) and school staff (20) and observations during 15 HWWS involving children., Results: Observations and interview data from children demonstrated that children were visibly excited and pleased with HWWS sessions where teachers applied active teaching methods including rewards, games and HWWS demonstrations. All children, schoolteachers and parents also viewed the HWWS intervention as positive and feasible, irrespective of ethnicity, gender of schoolchildren and background of schoolteachers. However, some important barriers were indicated for sustaining and transferring the HWWS practice to the home setting including limited emphasis on hygiene in the standard curriculum of schools, low priority and lack of time given to practical teaching methods and lack of guidance and reminding HWWS on a regular basis at home, in particular by highland parents, who spend most of their time working away from home in the fields. Access to soap and water at the household level did not seem a barrier for the uptake of HWWS but continuous access to these might be a challenge at schools., Conclusions: This study demonstrated that it is feasible to engage teachers and implement active teaching methods for behaviour change of HWWS in a group of multi-ethnic primary schoolchildren without the need for major investments in water and hygiene infrastructures. However, in those areas there was limited transfer of practice from school promotion to home. Continuous access to soaps at schools needs to be invested.

Background: In Vietnam, efforts are underway to improve latrine use in rural and remote areas with particular focus on increasing coverage of sanitation in schools. However, there is a lack of information on how the school program affects latrine use by schoolchildren and at community level. This paper analyzes sanitation use among schoolchildren in a multi-ethnic area to inform future school-based sanitation promotion programmes., Methods: A combination of quantitative and qualitative methods was applied during a 5 months period in six primary and secondary schools and in the homes of schoolchildren in four different ethnic villages in Northern rural Vietnam. Using a structured questionnaire, 319 children were interviewed face-to-face to collect quantitative data. Qualitative methods included extensive observations at schools and in the homes of 20 children, a single day's diary writings of 234 children, in-depth interviews with children (20), their parents (20) and school staff (10), and focus group discussions with parents (4) and teachers (6), and picture drawing with children (12)., Results: All surveyed schools had student latrines. However, the observed schoolchildren most commonly urinated and defecated in the open. Main barriers for latrine use included inadequate number of latrines, limited accessibility to latrines, lack of constant water supply in latrines and lack of latrine maintenance by school management. Programs promoting latrine use for children were not conducted in either schools or communities and were not established as a preferred social norm in such settings. Children perceived existing school latrines as unappealing and expressed a wish to have basic, functional, clean, and colorful school latrines with privacy., Conclusions: The paper shows that the current school based sanitation promotion is insufficient to change sanitation behavior of school children irrespective of their ethnicity. It is important that schools, households and communities work more closely together to increase use and uptake of latrine use among schoolchildren. Also, the contractors of latrine facilities must work more closely with local school management when constructing latrines, including identifying location, design and appropriate systems of water supply. A separate budget needs to be allocated to allow the school to maintain the sanitation infrastructure and keep it hygienic and appealing for users.

Background: The WHO recognises pesticide poisoning to be the single most important means of suicide globally. Pesticide self-poisoning is a major public health and clinical problem in rural Asia, where it has led to case fatality ratios 20-30 times higher than self-poisoning in the developed world. One approach to reducing access to pesticides is for households to store pesticides in lockable "safe-storage" containers. However, before this approach can be promoted, evidence is required on its effectiveness and safety., Methods/design: A community-based cluster randomised controlled trial has been set up in 44,000 households in the North Central Province, Sri Lanka. A census is being performed, collecting baseline demographic data, socio-economic status, pesticide usage, self-harm and alcohol. Participating villages are then randomised and eligible households in the intervention arm given a lockable safe storage container for agrochemicals. The primary outcome will be incidence of pesticide self-poisoning over three years amongst individuals aged 14 years and over. 217,944 person years of follow-up are required in each arm to detect a 33% reduction in pesticide self-poisoning with 80% power at the 5% significance level. Secondary outcomes will include the incidence of all pesticide poisoning and total self-harm., Discussion: This paper describes a large effectiveness study of a community intervention to reduce the burden of intentional poisoning in rural Sri Lanka. The study builds on a strong partnership between provincial health services, local and international researchers, and local communities. We discuss issues in relation to randomisation and contamination, engaging control villages, the intervention, and strategies to improve adherence.

Rotavirus infections are the most common cause of severe diarrhoea in children worldwide. Two internationally licensed rotavirus vaccines have proven to be efficacious in middle and high-income countries and they could potentially be valuable tools for the prevention of rotavirus-associated diarrhoea in low-income countries where the disease burden is greatest. However, before the vaccines can be introduced into the national immunisation programmes in these countries, many challenges related to the financing of vaccine purchase, the cold chain capacity and vaccine efficacy must be overcome. There is also a need for political commitment to prevent rotavirus infections as well as a need for an overall strengthening of the health systems in low-income countries. If these challenges were met, rotavirus vaccination could substantially improve child health and survival from rotavirus-associated diarrhoea.

When implementing water and sanitation in a disaster situation, it is of crucial importance that the intervention is grounded in the local cultural and socioeconomic context. The assistance provided in the response phase should facilitate short and long-term recovery and sustainable development of the affected community. The new model for disaster management which comprises an integrated continuous risk reduction phase, calls for a cross-disciplinary approach which combines the known life-saving response methods with modern development practices.

The predicted changes in climate have raised concerns that vector-borne diseases may emerge or expand in tempered regions. Malaria, leishmaniasis and tick-borne illnesses are discussed in terms of climate change and their endemic potential, especially in Denmark. While climate may play an important role in disease patterns, it is evident that transmission potential is governed by a complex of factors, including socio-economy, health-care capacity and ecology. In Denmark, malaria and leishmaniasis are unlikely to become public health problems, whereas the potential for tick-borne illnesses may increase.

The use of human excreta as fertiliser in agriculture is a common practice in parts of South East Asia benefiting production but at the same time a risk factor for increased helminth infections. This paper describes the hygienic handling of human excreta for use in agriculture in Central Vietnam from a practical farming perspective presenting the farmers perceived health risks and benefits of its use. Further, in the study findings are discussed relating to the new Vietnamese guidelines for the use of human excreta in agriculture to their implications on an on-farm context. A total of 471 households in five communes responded to a structured questionnaire. This survey was supplemented by focus group discussions, key informant interviews and participant observations. More than 90% of the surveyed households used their own excreta as fertiliser and a total of 94% composted the excreta before use, either inside or outside the latrine. However, due to the prevailing design of the latrine and the three annual cropping seasons, it was found that for a minimum of one cultivation season per year 74% of the households will have only 3-4 months for composting before the input is needed in production, which is short of the 6 months stipulated in the national guidelines. The community associated great benefits from using human excreta in agriculture, especially if composted, and did not associate risks with the use of composted excreta if it was dry and lacked odour. It is recommended that the guidelines be revised and attempts made to identify ways of reducing the time needed to ensure the die-off of helminth eggs, including the use of pH regulators, such as an increased use of lime in the latrines.

Vietnamese farmers' health-risk awareness, knowledge, and practices related to their use of wastewater and human excreta was investigated in an anthropological study by a multidisciplinary team in peri-urban Hanoi and Nghe An Province. Farmers identified health risks associated with their use of excreta and wastewater, but they viewed these as unavoidable risks related to production. They perceived the health risks as different for the use of wastewater and human feces. They perceived health risks from wastewater as non-serious because it remained on the skin and only caused skin problems, but they considered health risks from non-composted smelly feces serious because it entered the body through 'polluted' air. Most farmers were more aware of threats to health from 'dirt' entering the domestic environment than of the health risks during their work. The concept of 'dirt' should be separated from understanding of germs, viruses, and parasites so that it is understood that things that carrying health risks cannot always be identified by their 'dirtiness' or smell. Farmers mainly considered hygiene and health as women's issues. Men's responsibility for the health and hygiene of the family should therefore be emphasized.

Acute pesticide poisoning has become a major public health problem worldwide, following the intensification of agriculture and the promotion of agro-chemicals in low and middle income countries, with more than 300,000 deaths each year. The easy availability of highly toxic pesticides in the homes of farming communities has made pesticides the preferred means of suicide with an extremely high case fatality. Similarly, the extensive use of pesticides exposes the community to both long-term and acute occupational health problems. A concerted effort is urgently needed to address the situation.

Following the intensification of agriculture and the promotion of agro-chemicals in low and middle income countries, acute pesticide poisoning has become a major public health problem with more than 300,000 deaths each year around the world. The easy availability of highly toxic pesticides in the homes of farming communities has made pesticides a preferred choice for suicide with an extremely high case fatality. Similarly, the extensive use of pesticides exposes the community to both long-term and acute occupational health problems. A concerted effort is urgently needed to address this problem.

Background: Acute poisoning, especially deliberate self-poisoning with agricultural pesticides, is an emerging global public health problem, but reliable incidence estimates are lacking. Only a few previous studies have assessed the impact of regulatory or other preventive measures., Objective: To estimate trends in incidence and causes of acute poisoning over time in rural Sri Lanka, and to assess the possible impact of policies that aimed to restrict availability of highly toxic pesticides., Methods: Time series of incidence of acute poisoning based on retrospective in-patient records of six government hospitals in southern Sri Lanka from 1990 to 2002., Results: Data of 8,110 admissions for acute poisoning were available for analysis. Most cases were young adults, who deliberately self-poisoned themselves with pesticides, males outnumbering females. Average incidence rate of acute poisoning over the study period was 318 per 100,000 (95% confidence interval [CI], 311 to 325). Incidence of all poisoning showed an increase over the period of study. However, this increase was lower for pesticide poisoning, and the mortality rate and case fatality ratio of pesticides went down towards the end of the 1990s. The decline in mortality was attributed to regulatory controls for the group of highly hazardous organophosphorus compounds implemented in 1995 and for the organochlorine endosulfan in 1998., Conclusions: Regulatory control of highly toxic pesticides provides important health benefits, especially in terms of lower number of deaths from self-poisoning. However, despite the positive effect of these bans, many deaths from pesticide self-poisoning still occur after ingestion of agricultural pesticides classified as only moderately poisonous.

Malaria risk factor studies have traditionally used microscopy readings of blood slides as the measure of malaria infection in humans, although alternatives are available. There is the need for an assessment of how the use of these alternative diagnostic approaches will influence the efficiency and significance of epidemiological studies. In an area of Sri Lanka with known risk factors for malaria, two cross-sectional surveys were done at the start and at the peak of transmission season. Microscopy was compared with enzyme-linked immunosorbent assays (ELISA) and polymerase chain reaction (PCR). The major risk factor in this area was the location of houses relative to confirmed vector breeding sites. At the peak of the transmission season, the results pointed in the same direction, irrespective of the diagnostic method used. However, the importance of distance from the breeding site was not statistically significant when microscopy was used, which can be explained by the lower prevalence of microscopy positivity in comparison to the prevalence of ELISA- and PCR-positivity. This study suggests that in low-transmission areas, such as Sri Lanka, smaller sample sizes can be used for epidemiological research studies using PCR instead of microscopy to estimate parasite prevalence. This efficiency gain has to be weighed against the higher cost and complexity of the PCR. PCR cannot replace microscopy as the standard diagnostic procedure at the field level. ELISA is not directly comparable with microscopy and PCR but it can also be a useful tool in malaria epidemiological studies. This study indicates that cross-sectional surveys are only efficient if they take place during peak transmission season. Cross sectional surveys currently implemented by the Sri Lankan government in response to local malaria outbreaks can form the basis for valid epidemiological studies and be used for the generation of malaria risk maps if samples were also analyzed using PCR.

This study was carried out in the southern Punjab, Pakistan, to outline the causes of childhood diarrhea as perceived by mothers. Two hundred households in ten villages were randomly selected. Information was obtained from mothers, through a questionnaire, in-depth interviews, and direct observations. The focus was on obtaining information from mothers of children who were below five years of age. Causes of diarrhea reported by mothers were categorized in seven different domains. Causes relating to the digestive system, especially consumption of too much food, were the most important, followed by causes pertaining to contamination and those pertaining to the humoral theory of 'hot' and 'cold'. The mothers' health status was perceived as determining the health of her child through her breast milk. Through in-depth interviews, diarrhea as a symptom of envy and malice was brought up. The study draws attention to the complexity and heterogeneity of beliefs, attitudes and practices concerning diarrhea. This makes it difficult to come up with general rules for health education campaigns. Rather, in health education, the outstanding 'good' and 'bad' behavior should be selected and should be the focus. On the other hand, the heterogeneity of beliefs, attitudes and practices prevailing in the community could make mothers more receptive to new ideas than when a small set of rigid cultural norms would dominate thinking on disease transmission and hygiene. The study found that despite the mother's central role as caretaker one should not focus only on the traditional mother-child relationship, but also include the husband-wife relationship, and target other individuals involved in setting norms within the household or within the nearby community.

Mosquito breeding within the wastewater irrigation system around the town of Haroonabad in the southern Punjab, Pakistan, was studied from July to September 2000 as part of a wider study of the costs and benefits of wastewater use in agriculture. The objective of this study was to assess the vector-borne human disease risks associated with mosquito species utilizing wastewater for breeding. Mosquito larvae were collected on a fortnightly basis from components of the wastewater disposal system and irrigated sites. In total, 133 samples were collected, about equally divided between agricultural sites and the wastewater disposal system. Overall, 17.3% of the samples were positive for Anopheles, 12.0% for Culex and 15.0% for Aedes. Four anopheline species, viz, Anopheles stephensi (84.3% of total anophelines), An. subpictus (11.8%), An. culicifacies (2.0%) and An. pulcherrimus (0.2%) were present, as were two species of Culex, viz, Cx. quinquefasciatus (66.5% of culicines) and Cx. tritaeniorhynchus (20.1%). Aedes were not identified to species level. The occurrence of different species was linked to particular habitats and habitat characteristics such as physical water condition, chemical water quality and the presence of fauna and flora. Anophelines and Aedes mosquitos were mainly collected during the month of July, while Culex were collected in September. The prevalence of established vectors of human diseases such as An. stephensi (malaria), Cx. tritaeniorhynchus (West Nile fever, Japanese encephalitis) and Cx. quinquefasciatus (Bancroftian filariasis, West Nile fever) in the wastewater system indicated that such habitats could contribute to vector-borne disease risks for human communities that are dependent upon wastewater use for their livelihoods. Wastewater disposal and irrigation systems provide a perennial source of water for vector mosquitos in semi-arid countries like Pakistan. Vector mosquitos exploit these sites if alternative breeding sites with better biological, physical, and chemical conditions are not abundant.

This paper provides a review of surveys on soil-transmitted helminths that were done in Vietnam between 1990 and 2001. Prevalence estimates could be obtained for 29 of the 61 provinces. Extrapolating from this, it is estimated that 33.9 million people in Vietnam are infected with Ascaris (prevalence 44.4%), 17.6 million with Trichuris (prevalence 23.1%), and 21.8 million with hookworm (prevalence 28.6%). Prevalence of Ascaris and Trichuris showed a declining trend from the north to the south of the country. This is probably related to differences in climatic conditions. Hookworm prevalence is more evenly distributed throughout the country, but is concentrated in peri-urban and rural agricultural areas. Vegetable cultivation in which nightsoil is used as fertilizer is a risk factor for hookworm infection, especially among adult women. Helminth control programs should be targeted at school-age children in the northern provinces. Specific interventions are needed throughout the country for women of agricultural communities that are at risk for hookworm infection. There is clearly a need for more detailed analysis of risk factors to quantify the relative contribution of climatic, environmental, and human behavioral factors in the transmission of intestinal nematode infections in Vietnam.

This study assessed whether availability of water for domestic use had any impact on nutritional status of children in an area where people depend on irrigation water for all their domestic water needs. During May 1998-April 1999, data on the occurrence of diarrhoea among 167 children aged less than five years were collected from 10 villages in the command area of the Hakra 6R canal in southern Punjab, Pakistan. Anthropometric measurements were taken at the end of the study period. Additional surveys were conducted to collect information on the availability of water, sanitary facilities, hygiene, and socioeconomic status. Height-for-age and longitudinal prevalence of diarrhoea were used as outcome measures. Quantity of water available in households was a strong predictor of height-for-age and prevalence of diarrhoea. Children from households with a large storage capacity for water in the house had a much lower prevalence of diarrhoea and stunting than children from families without this facility. Having a toilet was protective for diarrhoea and stunting. Increased quantity of water for domestic use and provision of toilet facilities were the most important interventions to reduce burden of diarrhoea and malnutrition in this area. An integrated approach to water management is needed in irrigation schemes, so that supply of domestic water is given priority when allocating water in time and space within the systems.