Adults' perceived prevalence of enteric fever predicts laboratory-validated incidence of typhoid fever in children.

This study was undertaken to develop a model to predict the incidence of typhoid in children based on adults' perception of prevalence of enteric fever in the wider community. Typhoid cases among children, aged 5-15 years, from epidemic regions in five Asian countries were confirmed with a positive Salmonella Typhi culture of the blood sample. Estimates of the prevalence of enteric fever were obtained from random samples of adults in the same study sites. Regression models were used for establishing the prediction equation. The percentages of enteric fever reported by adults and cases of typhoid incidence per 100,000, detected through blood culture were 4.7 and 24.18 for Viet Nam, 3.8 and 29.20 for China, 26.3 and 180.33 for Indonesia, 66.0 and 454.15 for India, and 52.7 and 407.18 for Pakistan respectively. An established prediction equation was: incidence of typhoid (1/100,000= -2.6946 + 7.2296 x reported prevalence of enteric fever (%) (F=31.7, p<0.01; R2=0.992). Using adults' perception of prevalence of disease as the basis for estimating its incidence in children provides a cost-effective behavioural epidemiologic method to facilitate prevention and control of the disease.

Sexual behaviors of alcohol drinkers and non-drinkers among adolescents and young adults in Nha Trang, Vietnam.

A cross-sectional quantitative survey was conducted during August to November 2005 with 880 youths (16-24 years-old), including 412 males and 468 females in Nha Trang city, Vietnam. It aimed to examine the association between alcohol use and sexual behaviors by gender difference. The data revealed that the majority of respondents (65.9%) had consumed alcohol, 25.8% had sexual touching with boy/girl friends, and 10.1% of respondents had engaged in sexual experiences including vaginal sex, anal sex, and/or oral sex. Young men were significantly more likely to drink than young women were (p < 0.001), and alcohol use was significantly associated with engagement in sexual experiences (p < 0.001). There was a strong significant different between sexual touching and alcohol drinking among males (p < 0.001) and females (p < 0.001). Forty percent of young men who did not use condom in last sex and 45% of young men who had multiple sex partners were drinkers compared to 4.8% and 1.6% of non-drinkers, respectively. These significant findings will be baseline data for integrating and adapting into intervention programs for alcohol and HIV among Vietnamese youth.

Sociobehavioural research methods for the introduction of vaccines in the Diseases of the Most Impoverished Programme.

Participation in vaccination campaigns worldwide, particularly the Expanded Programme on Immunization, has increased significantly in recent years. However, there remain multiple and integrated behavioural, sociocultural and political-economic barriers to vaccination. The Diseases of the Most Impoverished (DOMI) Programme has undertaken shigellosis disease-burden studies and oral cholera and typhoid Vi polysaccharide vaccine trials in seven Asian countries. As part of these projects, sociobehavioural studies have been undertaken to determine the potential demand for vaccines for these diseases and the obstacles and enabling factors that may affect acceptance, delivery, and use of vaccines. A theoretical model of acceptance of vaccination and a triangulation of qualitative and quantitative methods have been used for fully elucidating the range of issues relating to vaccination for shigellosis, cholera, and typhoid fever. In this paper, the theoretical and methodological basis of the DOMI projects has been reviewed in a context of current sociobehavioural research on the acceptability and desirability of vaccination.

Healthcare use for diarrhoea and dysentery in actual and hypothetical cases, Nha Trang, Viet Nam.

To better understand healthcare use for diarrhoea and dysentery in Nha Trang, Viet Nam, qualitative interviews with community residents and dysentery case studies were conducted. Findings were supplemented by a quantitative survey which asked respondents which healthcare provider their household members would use for diarrhoea or dysentery. A clear pattern of healthcare-seeking behaviours among 433 respondents emerged. More than half of the respondents self-treated initially. Medication for initial treatment was purchased from a pharmacy or with medication stored at home. Traditional home treatments were also widely used. If no improvement occurred or the symptoms were perceived to be severe, individuals would visit a healthcare facility. Private medical practitioners are playing a steadily increasing role in the Vietnamese healthcare system. Less than a quarter of diarrhoea patients initially used government healthcare providers at commune health centres, polyclinics, and hospitals, which are the only sources of data for routine public-health statistics. Given these healthcare-use patterns, reported rates could significantly underestimate the real disease burden of dysentery and diarrhoea.

Acceptability and accessibility of a Shigellosis vaccine in Nha Trang city of Viet Nam.

The acceptability and accessibility of a hypothetical Shigella vaccination campaign was explored. A household survey was conducted with 539 randomly-selected residents of six communes in Nha Trang city of Viet Nam. Four categories of acceptability, such as refusers, low acceptors, acceptors, and high acceptors, were established, Refusers were significantly more likely to be elderly women and were less likely to know the purpose of vaccinations. Low acceptors tended to be male, elderly, and live in urban areas. Low acceptors perceived the disease as less serious and themselves as less vulnerable than acceptors and high acceptors. In terms of accessing vaccination, the commune health centre workers and commune leaders were the preferred sources of information and commune health centres the preferred location for vaccination. Direct verbal information from healthcare providers and audio-visual media were preferred to written information. The respondents expressed a desire for knowledge about the side-effects and efficacy of the vaccine. These findings are significant for targeting specific messages about shigellosis and vaccination to different populations and maximizing informed participation in public-health campaigns.