Predictors and burden of injury mortality in the Thai cohort study 2005-2015.

BACKGROUND: Thailand is a high injury burden setting. In 2015 it had the world's second highest rate of road traffic fatalities. In order to develop strategies to reduce this burden an accurate understanding of the development of injury risk over the life course is essential. METHODS: A national cohort of adult Thais was recruited in 2005 (n = 87,151). Participants completed a health questionnaire covering geodemographic, behavioural, health and injury data. Citizen ID numbers were matched with death registration records, identifying deaths from any injury. Adjusted logistic regression models were used to measure associations between baseline exposures and injury deaths between 2005 and 2015. RESULTS: Injury mortality comprised 363 individuals, the majority (36%) from traffic injuries. Predictors of all-injury mortality were being male (AOR 3.55, 95% CI 2.57-4.89), Southern Thai (AOR 1.52, 95% CI 1.07-2.16), smoking (AOR 1.55, 95% CI 1.16-2.17), depression (AOR 1.78, 95% CI 1.07-2.96), previous injury (AOR 1.37, 95% CI 1.03-1.81) and drink driving history (AOR 1.37, 95%CI 1.02-1.85). Age and region of residence were stronger predictors for men, while anxiety/depression was a stronger predictor for women. Among males in the far south, assault caused the largest proportion of injury mortality, elsewhere traffic injury was most common. CONCLUSIONS: This study identifies that a history of drink driving, but not regular alcohol consumption, increased injury risk. The associations between smoking and depression, and injury mortality also need further consideration.

Effect of diabetes on tuberculosis presentation and outcomes in Kiribati.

OBJECTIVES: To determine the association between diabetes and the clinical features and treatment outcomes of TB in Kiribati. METHODS: We enrolled consecutive patients with TB who presented from August 2010 to February 2012 and compared clinical features and TB treatment outcomes for patients with and without diabetes, as measured by haemoglobin A1c assay. Poor outcome was defined as death, default or treatment failure, and good outcome as treatment success or cure. RESULTS: Two hundred and seventy-five eligible persons with TB disease were enrolled; 101 (37%) had diabetes. TB patients with diabetes were more likely to have acid-fast bacilli (AFB) seen on sputum smear microscopy (RR: 1.3; 95% CI: 1.03-1.62). The risk of poor outcome did not differ between patients with or without diabetes (RR: 1.1; 95% CI: 0.5-2.7). CONCLUSION: TB patients with diabetes are more likely than those without to have sputum with AFB on microscopy. This could increase transmission in the community. Early detection of TB by screening patients with diabetes, and the converse, could be important public health interventions where diabetes and TB are prevalent.

Tuberculosis and diabetes mellitus in the Republic of Kiribati: a case-control study.

OBJECTIVES: To better inform local management of TB-diabetes collaborative activities, we aimed to determine the prevalence of diabetes among persons with and without TB and to determine the association between TB and diabetes in Kiribati, a Pacific Island nation. METHODS: We compared consecutively enrolled TB cases to a group of randomly selected community controls without evidence of TB. Diabetes was diagnosed by HbA1c, and clinical and demographic data were collected. A tuberculin skin test was administered to controls. The chi-square test was used to assess significance in differences between cases and controls. We also calculated an odds ratio, with 95% confidence intervals, for the odds of diabetes among cases relative to controls. Unweighted multivariate logistic regression was performed to adjust for the effects of age and sex. RESULTS: A total of 275 TB cases and 499 controls were enrolled. The diabetes prevalence in cases (101, 37%) was significantly greater than in controls (94, 19%) (adjusted odds ratio: 2.8; 95% CI 2.0-4.1). Fifty-five percent (108) of all diabetic diagnoses were new; this proportion was higher among controls (64.8%) than cases (46.5%). Five patients with TB were screened to detect one patient with diabetes. CONCLUSIONS: There is a strong association between TB and diabetes in Kiribati and bidirectional screening should be conducted in this setting.

Validity of self-reported abdominal obesity in Thai adults: a comparison of waist circumference, waist-to-hip ratio and waist-to-stature ratio.

BACKGROUND AND AIMS: Waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-stature ratio (WSR), being common proxy measures of abdominal obesity, are useful tools in epidemiologic studies, but little is known about their validity when the indices are derived from self-reported measurements. We determine and compare the validity of self-reported WC, WHR and WSR in order to identify the optimal index for use in epidemiologic surveys. METHODS AND RESULTS: Technician- and self-reported measurements of height, waist and hip circumference were obtained from 613 Thai adults (mean age 35 years). Regarding technician-reported measurements as reference, diagnostic test properties were derived and performances of the indices compared using receiver-operator-characteristic curves and the area-under-the-curve (AUC) analyses. There was good agreement between technician- and self-reported measurements for WC and WSR (concordance correlation coefficients ranged from 0.84 to 0.90) but not for WHR (0.50 in men, 0.45 in women). The sensitivity and specificity of self-reported WC and self-reported WSR as measures of abdominal obesity were superior to those of self-reported WHR in both sexes. AUCs for WC and WSR were comparable (0.93 and 0.92, respectively, in men; 0.88 and 0.87 in women) and significantly higher than for WHR (0.80 in men; 0.76 in women; p<0.0001). CONCLUSION: WC and WSR derived from self-reported waist and height measurements are valid methods for determining abdominal obesity. Self-reported measurements should not be used to derive the WHR. In Asian populations, WSR may be the optimal index of abdominal obesity when measurements are derived from self-reports in epidemiologic surveys.

Risk factors for injury in a national cohort of 87,134 Thai adults.

BACKGROUND: Information is needed regarding risk factors associated with injury. In middle- and lower-income countries, injury studies have focused on road traffic injuries and less attention has been given to other types of injuries. METHODS: This study is part of overarching health-risk transition research in Thailand with a large national cohort study that began in 2005 (n = 87,134). Associations between potential determinants and overall injury were measured, as well as injury by location (transport, home, work and sport), using data gathered from the baseline questionnaire. RESULTS: In total, 21.5% of the cohort reported at least one incidence of injury over the last 12 months. Risk factors associated with injury were being male [odds ratio (OR) 1.20], having lower income (OR 1.70), having problems with vision (OR 1.46), having epilepsy (OR 3.02), having depression/anxiety (OR 1.62), poor self-assessed health (OR 1.68), being obese (OR 1.24) and death of father due to injury (OR 1.59). Analysis of injury by location provided more specific information on risk factors. For example, females were more likely to report injuries at home, while males, urban residents and regular alcohol drinkers were more likely to report transport injuries. CONCLUSIONS: The risk of injury in Thailand varies considerably by location, sociodemographic group and several categories of co-existing morbidities. Such epidemiological information identifying risk factors for injury is useful for designing targeted injury prevention programmes in Thailand and other middle-income countries.

The effects of aerobic exercise on metabolic risk, insulin sensitivity and intrahepatic lipid in healthy older people from the Hertfordshire Cohort Study: a randomised controlled trial.

AIMS/HYPOTHESIS: We sought to determine the effect of an aerobic exercise intervention on clustered metabolic risk and related outcomes in healthy older adults in a single-centre, explanatory randomised controlled trial. METHODS: Participants from the Hertfordshire Cohort Study (born 1931-1939) were randomly assigned to 36 supervised 1 h sessions on a cycle ergometer over 12 weeks or to a non-intervention control group. Randomisation and group allocation were conducted by the study co-ordinator, using a software programme. Those with prevalent diabetes, unstable ischaemic heart disease or poor mobility were excluded. All data were collected at our clinical research facility in Cambridge. Components of the metabolic syndrome were used to derive a standardised composite metabolic risk score (zMS) as the primary outcome. Trial status: closed to follow-up. RESULTS: We randomised 100 participants (50 to the intervention, 50 to the control group). Mean age was 71.4 (range 67.4-76.3) years. Overall, 96% of participants attended for follow-up measures. There were no serious adverse events. Using an intention-to-treat analysis, we saw a non-significant reduction in zMS in the exercise group compared with controls (0.07 [95% CI -0.03, 0.17], p = 0.19). However, the exercise group had significantly decreased weight, waist circumference and intrahepatic lipid, with increased aerobic fitness and a 68% reduction in prevalence of abnormal glucose metabolism (OR 0.32 [95% CI 0.11-0.92], p = 0.035) compared with controls. Results were similar in per-protocol analyses. CONCLUSIONS/INTERPRETATION: Enrolment in a supervised aerobic exercise intervention led to weight loss, increased fitness and improvements in some but not all metabolic outcomes. In appropriately screened older individuals, such interventions appear to be safe. TRIAL REGISTRATION: Controlled-trials.com ISRCTN60986572 FUNDING: Medical Research Council.

Rationale, design and methods for process evaluation in the HEALTHY study.

The HEALTHY study was a multi-site randomized trial designed to determine whether a 3-year school-based intervention targeting nutrition and physical activity behaviors could effectively reduce risk factors associated with type 2 diabetes in middle school children. Pilot and formative studies were conducted to inform the development of the intervention components and the process evaluation methods for the main trial. During the main trial, both qualitative and quantitative assessments monitored the fidelity of the intervention and motivated modifications to improve intervention delivery. Structured observations of physical education classes, total school food environments, classroom-based educational modules, and communications and promotional campaigns provided verification that the intervention was delivered as intended. Interviews and focus groups yielded a multidimensional assessment of how the intervention was delivered and received, as well as identifying the barriers to and facilitators of the intervention across and within participating schools. Interim summaries of process evaluation data were presented to the study group as a means of ensuring standardization and quality of the intervention across the seven participating centers. Process evaluation methods and procedures documented the fidelity with which the HEALTHY study was implemented across 21 intervention schools and identified ways in which the intervention delivery might be enhanced throughout the study.

Ethical challenges in TB control in the era of XDR-TB.

Tuberculosis (TB) is the second leading cause of preventable illness worldwide and arguably the most important neglected topic in bioethics. This paper 1) explains the ethical importance of TB, 2) documents its neglect in bioethics discourse, 3) maps the terrain of ethical issues associated with TB, and 4) calls for ethicists, activists and socially concerned health professionals to raise and debate the full range of ethical issues associated with TB.

Consumption of sugar-sweetened beverages and type 2 diabetes incidence in Thai adults: results from an 8-year prospective study.

BACKGROUND: The global prevalence of type 2 diabetes mellitus (T2DM) is high and is increasing in countries undergoing rapid socio-economic development, including Thailand. Sugar-sweetened beverage (SSB) intake may contribute to the risk of developing T2DM. However, few studies have assessed this association in Asian populations, and the results have been inconsistent. We aimed to assess that association in a prospective study of Thai adults. METHODS: Data were from Thai Cohort Study participants surveyed in 2005, 2009 and 2013. The nation-wide sample included adult cohort members who were free of diabetes in 2005 and who were followed-up in 2013 (n=39 175). We used multivariable logistic regression to assess associations between SSB intake and eight-year T2DM incidence. We used a counterfactual mediation analysis to explore potential mediation of the SSB intake and T2DM-risk relationship. RESULTS: In women (but not men) consuming SSBs once or more per day (versus rarely) was associated with increased T2DM incidence at the 8-year follow-up (odds ratio (OR)=2.4, 95% confidence interval (CI) 1.5-3.9). Obesity in 2009 was found to mediate ~23% of the total association between SSB intake in 2005 and T2DM risk in 2013 (natural indirect effect 1.15, 95% CI (1.02, 1.31). CONCLUSIONS: Frequent SSB consumption associated with higher T2DM incidence in women but not men. We found that a moderate proportion of the SSB-T2DM relationship was mediated through body mass index (BMI). Our findings suggest that targeting SSB consumption can help prevent a national rise in the incidence of T2DM.

Validity of visceral adiposity estimates from DXA against MRI in Kuwaiti men and women.

OBJECTIVES: The prevalence of obesity and diabetes in the Middle East is among the highest in the world. Valid measures of abdominal adiposity are essential to understanding the metabolic consequences of obesity. Dual-energy X-ray absorptiometry (DXA) is increasingly being utilised to assess body composition in population studies, and has recently been used to estimate visceral adipose tissue (VAT). The aim of this study was to determine the accuracy of DXA-derived VAT in a Middle Eastern population using magnetic resonance imaging (MRI) as the criterion measure. METHOD: VAT was estimated from abdominal DXA measures in 237 adult men (n=130) and women (n=107), aged 18-65 years, participating in the Kuwait Wellbeing Study. These estimates were compared with MRI measures of the corresponding anatomical region. The agreement between methods was assessed using Bland-Altman as well as correlation analysis. RESULTS: Median MRI VAT was 1148.5 cm3 (95% confidence interval: 594.2-1734.6) in men and 711.3 cm3 (95% confidence interval: 395.5-1042.8) in women. DXA estimates of VAT showed high correlations with corresponding MRI measures (r=0.94 (P<0.0001) in men; r=0.93 (P<0.0001) in women). DXA overestimated VAT with a mean bias (95% limits of agreement) of 79.7 cm3 (-767 to 963) in men and 46.8 cm3 (-482 to 866) in women. The imprecision of DXA increased with increasing VAT level in both men and women. CONCLUSION: DXA estimates of VAT are valid for use in Middle Eastern populations, although accuracy decreases with increasing level of visceral adiposity.

Poverty and the economic effects of TB in rural China.

OBJECTIVE: To investigate the economic effects of illness on individual tuberculosis (TB) cases in rural China and to use a case-control study to show a strong TB-poverty link. SETTING: In 2002-2004 we studied 160 new smear-positive pulmonary tuberculosis (PTB) cases and 320 age- and sex-matched controls living in neighbouring houses in four rural counties of Henan Province. DESIGN: Cases and controls were interviewed 1-3 months after patients were diagnosed. We used matched multivariate logistic regression to compare cases with controls for poverty status using household income, household assets and relative wealth within the village. We conducted follow-up interviews of patients 10-12 months later to assess economic effects by collecting data on treatment costs, income losses, coping strategies and treatment completion. RESULTS: Poverty is strongly associated with TB incidence even after controlling for smoking and other risk factors. Excluding income losses, direct out-of-pocket treatment costs (medical and non-medical) accounted for 55.5% of average annual household income, and most TB cases fell into heavy debt. The DOTS cure rate was 91%. When DOTS was incomplete or not done, mortality was high. CONCLUSIONS: Poverty is both a cause and a devastating outcome of TB. Ongoing poverty reduction schemes in China must also include reducing TB.

Trust: The Missing Dimension in the Food Retail Transition in Thailand.

Thailand has experienced dramatic growth of large national and international modern food retailers, such as supermarkets, hypermarkets and convenience stores in large cities and regional centres in the last two decades. Nevertheless, Thai consumers continue to purchase perishables (fruits, vegetables and animal products) from fresh markets (wet markets, talat sot) contradicting predictions from analysts that modern food retail chains will rapidly replace fresh markets as the preferred venue for purchasing all types of foods. This paper examines trust in food retail systems as an under-explored dimension lying behind the continued patronage by Thais of fresh markets to purchase perishable items. It derives from a research program commenced in 2005 that includes fieldwork visits, interviews and questionnaires. In the context of the Thai food retail transition, we propose that trust affects relationships between consumers and (1) individual fresh market-based vendors, (2) the food products sold at fresh markets and (3) the food retail system more broadly. If fresh markets can be maintained in the face of sustained pressure from modern national and international food retailers, Thais will continue to use them. Meanwhile, trust is a relatively unrecognised dimension that is supporting the continued existence of traditional food retail formats.

Body size dynamics in young adults: 8-year follow up of cohorts in Brazil and Thailand.

Increase in body size has appeared as an epidemic in Western countries and is now rapidly emerging in low- and middle-income countries, contributing to the rise in non-communicable diseases worldwide. Brazil and Thailand have gone through similar economic and health transitions, and this unique comparative study investigates changes in body size (body mass index) in relation to socioeconomic status in two cohorts of similar age followed from 2004/2005 to 2012/2013. At 20-24 years of age, Pelotas cohort members had a much higher prevalence of overweight and obesity (20.7 and 8.6%) than the Thai cohort (6.0 and 1.7%); these proportions rose to 34.6% and 22.9% vs 15.8% and 5.1%, respectively, in their early 30s. An association between a higher socioeconomic status and increase in overweight and obesity was observed among males; but an inverse pattern was noted for females in both cohorts and remained statistically significant after 8 years of follow up. Our comparative longitudinal analyses highlight the relationship between two middle-income settings facing rapid increases in body size (2-3 fold increase in the rate of overweight and obesity). Long-term follow up and a lifecourse approach for effective prevention of obesity will minimize adverse health burdens in later life.

HLA class II antigens are associated with resistance or susceptibility to hepatosplenic disease in a Chinese population infected with Schistosoma japonicum.

The major histocompatibility Class II alleles of 108 individuals living in an area endemic for schistosomiasis japonica in China were determined to identify possible immunogenetic associations with advanced schistosomiasis. Two alleles, HLA-DRB1*1202 (P = 0.002) and HLA-DQA*0601 (P = 0.001) were strongly associated with resistance to advanced disease. In contrast, HLA-DQB1*05031 (P = 0.02) was associated with susceptibility to advanced schistosomiasis. The remaining alleles showed no association with advanced disease. Allele DRB1*1202 co-occurred with allele DQA1*0601; therefore, their independent protective effects could not be ascertained. In contrast, alleles DQA1*0601 and DQB1*05031 never co-occurred and had opposite and significant effects on the occurrence of disease.

Epidemiology of Schistosoma japonicum in China: morbidity and strategies for control in the Dongting Lake region.

Dongting Lake, covering a very large surface water area of 2691km(2), is located in Hunan Province in the southern part of the People's Republic of China. It is the second-largest freshwater lake in China and plays an important role in regulating the amount of water in the Yangtze River, China's longest river. The annual water level of the lake changes by as much as 15m, rising in summer and falling in winter. Asian schistosomiasis has been endemic in the Dongting Lake region for centuries and it has had a devastating effect on the public health of the local people. After a difficult struggle for more than four decades, a concerted programme, supported by the World Bank Loan and instigated in 1992, has resulted in remarkable progress in the control of the disease in many endemic areas of the region. However, the great challenge remains to consolidate and maintain the achievements made to date. The Schistosoma japonicum intermediate host (Oncomelania hupensis hupensis) snail habitats are huge, estimated at 1768km(2) in 1996; these are increasing at a rate of 34.7km(2) annually due to high silt deposition from the Yangtze River itself and from the connecting rivers in Hunan province, and construction of embankments in the Dongting Lake region. It is anticipated that the construction of the Three Gorges Super Dam, the largest engineering project ever undertaken, will substantially extend the range of the snail habitats and increase the number of new schistosomiasis cases. In many areas, human re-infections with S. japonicum after drug (praziquantel) treatment remain unacceptably high (up to 20% of those treated are re-infected annually) due to occupational (mainly fishing) water contact. This paper reviews the history and the current status of schistosomiasis control in the lake region, it explores the epidemiological factors which influence the prevalence of the infection and the disease it causes, and it provides insight into future approaches to control which might finally eradicate the infection.

HLA class II antigens positively and negatively associated with hepatosplenic schistosomiasis in a Chinese population.

To identify possible associations between host genetic factors and the onset of liver fibrosis following Schistosoma japonicum infection, the major histocompatibility class II alleles of 84 individuals living on an island (Jishan) endemic for schistosomiasis japonica in the Poyang Lake Region of Southern China were determined. Forty patients exhibiting advanced schistosomiasis, characterised by extensive liver fibrosis, and 44 age and sex-matched control subjects were assessed for the class II haplotypes HLA-DRB1 and HLA-DQB1. Two HLA-DRB1 alleles, HLA-DRB1*0901 (P=0.012) and *1302 (P=0.039), and two HLA-DQB1 alleles, HLA-DQB1*0303 (P=0.012) and *0609 (P=0.037), were found to be significantly associated with susceptibility to fibrosis. These associated DRB1 and DQB1 alleles are in very strong linkage disequilibrium, with DRB1*0901-DQB1*0303 and DRB1*1302-DQB1*0609 found as common haplotypes in this population. In contrast, the alleles HLA-DRB1*1501 (P=0.025) and HLA-DQB1*0601 (P=0.022) were found to be associated with resistance to hepatosplenic disease. Moreover, the alleles DQB1*0303 and DRB1*0901 did not increase susceptibility in the presence of DQB1*0601, indicating that DQB1*0601 is dominant over DQB1*0303 and DRB1*0901. The study has thus identified both positive and negative associations between HLA class II alleles and the risk of individuals developing moderate to severe liver fibrosis following schistosome infection.

Electronic telephone directory listings: preferred sampling frame for a population-based study of childhood cancer in Australia.

PURPOSE: We report our telephone-based system for selecting community control series appropriate for a complete Australia-wide series of Ewing's sarcoma cases. METHODS: We used electronic directory random sampling to select age-matched controls. The sampling has all listed telephone numbers on an up-dated CD-Rom. RESULTS: 95% of 2245 telephone numbers selected were successfully contacted. The mean number of attempts needed was 1.94, 58% answering at the first attempt. On average, we needed 4.5 contacts per control selected. Calls were more likely to be successful (reach a respondent) when made in the evening (except Saturdays). The overall response rate among contacted telephone numbers was 92.8%. Participation rates among female and male respondents were practically the same. The exclusion of unlisted numbers (13.5% of connected households) and unconnected households (3.7%) led to potential selection bias. However, restricting the case series to listed cases only, plus having external information on the direction of potential bias allow meaningful interpretation of our data. CONCLUSION: Sampling from an electronic directory is convenient, economical and simple, and gives a very good yield of eligible subjects compared to other methods.

An outbreak of Chagas' disease in southwestern Bahia, Brazil.

An outbreak of 20 cases of acute Chagas' disease followed the movement of Triatoma infestans into the county of Riacho de Santana, Bahia, Brazil. The outbreak was unusual in that the majority of cases occurred in adults. Vector control measures were implemented. Three years after the outbreak, a rural community was examined to determine the extent of human infection and disease due to Trypanosoma cruzi. Ninety of 440 residents (20.5%) had serologic evidence of infection, but rates of electrocardiographic (EKG) abnormalities were low. Comparison of age-specific rates of seropositivity and EKG abnormalities with rates from areas with endemic Chagas' disease supported the hypothesis of a recent epidemic. Control measures appear to have interrupted transmission in the region.

Epidemiologic features of Schistosoma japonicum among fishermen and other occupational groups in the Dongting Lake region (Hunan Province) of China.

In this study we examined 1,909 individuals (53% males and 47% females) to determine the current status of Schistosoma japonicum among the people in five fishing villages situated on two islands (large, Qingshan island; small, Niangashan island) in the Dongting Lake region in Hunan Province, the People's Republic of China. The results of this study indicate that the overall prevalence for schistosomiasis on the two islands is 16%. Two distinct peaks in prevalence (29%) were observed at 25-35 years of age and again at 45-55 years of age for both the large and small islands. On the small island the overall prevalence (24%) varied significantly (P < 0.01) from the large island (15%). Fishermen had the highest prevalence (22.4%) among all the occupational groups examined but students produced the highest worm intensity (geometric mean = 69 eggs per gram [epg] of feces). There was a significant difference (P < 0.01) in the prevalence of schistosomiasis between males and females. In general, males had a much higher prevalence (22%) than females (8.9%). When the study populations were classified as uninfected, lightly infected (10-100 epg), moderately infected (101-400 epg), and heavily infected (> 401 epg) with S. japonicum, the distribution pattern was similar for each of the five villages. The majority (76-88%) of the population remains uninfected. Lightly infected individuals had the highest prevalence (7-12%) followed by moderately infected individuals (1-9%). Only a very small percentage of the population was heavily infected (0-2%). Hepatomegaly along the midsternal line (MSL > or = 3) was commonly seen in both uninfected (21%) and infected individuals (1939%). Subjects heavily infected with S. japonicum reported significantly higher (P < 0.05) cases of liver enlargement when compared with those uninfected. The reported cases of abdominal pain for both uninfected (9%) and infected individuals (4-19%) was relatively high. Lightly and moderately infected individuals reported significantly (P < 0.05 and P < 0.01, respectively) more episodes of abdominal pain than those uninfected. The occurrence of diarrhea was low (5%) for uninfected individuals but this clinical feature was significantly (P < 0.01) more prevalent in both the lightly and heavily infected categories (8-17%).

A baseline study on the importance of bovines for human Schistosoma japonicum infection around Poyang Lake, China.

We hypothesize that bovine infections are responsible for the persistence of human schistosomiasis transmission in the Yangtze marshlands of China. To test this hypothesis, we are carrying out a comparative intervention among four administrative villages in the Poyang Lake region, Jiangxi Province, two of which are experimental and two are control. The primary design involves treating, at the onset of the study, all the inhabitants in all four villages with praziquantel and all the bovines in two villages (the experimental or intervention villages). Following treatment, rates of reinfection in people of all villages, and in bovines in the experimental villages, will be assessed as will the ongoing prevalence of infection in bovines in the control villages. Before treatment, the prevalence and intensity of infection among humans and bovines was ascertained in the four villages. Our study design and baseline information are presented here, along with a description of the ecology of the study villages.