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.

Private demand for cholera vaccines in Hue, Vietnam.

Objectives: This study aims to measure the private demand for oral cholera vaccines in Hue, Vietnam, an area of relatively low endemicity of cholera, using the contingent valuation method.

Methods: Interviews were conducted with either the head of household or spouse in 800 randomly selected households with children less than 18 years old. Respondents were asked whether they would purchase an oral cholera vaccine with different levels of effectiveness and durations of effectiveness (both for themselves and for other household members) at a specified price.

Comparison of cost-of-illness with willingness-to-pay estimates to avoid shigellosis: evidence from China.

Previous studies have shown that cost of illness (COI) measures are lower than the conceptually correct willingness-to-pay (WTP) measure of the economic benefits of disease prevention. We compare COI with stated preference estimates of WTP associated with shigellosis in a rural area of China. COI data were collected through face-to-face interviews at 7 and 14 days after culture-confirmed diagnosis.

Private demand for cholera vaccines in rural Matlab, Bangladesh.

Objectives: To estimate household willingness to pay (WTP) for cholera vaccines in a rural area of Bangladesh, which had participated in a 1985 oral cholera vaccine trial.

Methods: A contingent valuation study was undertaken in Matlab, Bangladesh in summer 2005. All respondents (N=591) received a description of a cholera vaccine that was 50% effective for 3 years and had negligible side effects.

The use of typhoid vaccines in Asia: the DOMI experience.

Background: Two currently licensed typhoid vaccines have been evaluated in Asia, yet few Asian countries have considered including typhoid vaccines in their vaccination programs. The Diseases of the Most Impoverished (DOMI) Program was initiated to provide evidence to decide on the introduction of typhoid vaccines in Asian countries.

Methods: The centerpiece of the program is a multidisciplinary demonstration project with Vi vaccine in 5 Asian countries.

Private demand for cholera vaccines in Beira, Mozambique.

In the summer of 2005, we interviewed 996 randomly selected respondents in Beira, Mozambique concerning their willingness and ability to pay for cholera vaccine for themselves and for other household members. Respondents were told that two doses of the vaccine would be required 2 weeks apart, and that the cholera vaccine would offer excellent protection against infection for the first year following vaccination, and some protection during the second and third year after a person is vaccinated. This research was carried out in order to learn more about private demand for vaccines in a cholera-endemic area.

Household demand for typhoid fever vaccines in Hue, Vietnam.

The demand function for vaccines against typhoid fever was estimated using stated preference data collected from a random sample of 1065 households in Hue, Vietnam, in 2002. These are the first estimates of private willingness-to-pay (WTP) and demand functions for typhoid vaccines in a developing country. Mean respondent WTP for a single typhoid fever vaccine ranged from USD 2.

Willingness to be vaccinated against shigella and other forms of dysentery: a comparison of three regions in Asia.

We conducted a cross sectional survey of 3163 women and men in six Asian countries to examine willingness for children and adults to be vaccinated against shigellosis and other forms of dysentery. The six sites were clustered into three regions for ease of comparison. The regions are: Northeast Asia (China), Southeast Asia (Thailand, Vietnam, and Indonesia) and South Asia (Bangladesh and Pakistan).

Policymakers' views regarding the introduction of new-generation vaccines against typhoid fever, shigellosis and cholera in Asia.

Face-to-face interviews and meetings with more than 160 policymakers and other influential professionals in seven large Asian countries (Bangladesh, China, India, Indonesia, Pakistan, Thailand and Vietnam) were conducted to survey opinions regarding the need for, and potential uses of new-generation vaccines against cholera, typhoid fever and shigellosis. Despite several barriers to their uptake--notably uncertainty of the burden of enteric diseases; preference for water, sanitation and other environmental improvements over vaccination for disease control; and high prices of the current vaccines relative to basic EPI vaccines, and their moderate protection levels--considerable interest was found in the targeted use of Vi typhoid vaccine in most countries, followed by (future) Shigella and oral cholera vaccines. The introduction of these vaccines in Asia could be greatly facilitated by country-specific evidence of disease burden, local or regional vaccine production, field studies demonstrating their safety and efficacy in local populations, evidence of potential economic savings from vaccination, and effective dissemination of research results to all those who make or influence immunization policy.

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.

The health belief model and factors relating to potential use of a vaccine for shigellosis in Kaeng Koi district, Saraburi province, Thailand.

Shigellosis is an important cause of morbidity and mortality throughout the world. Approximately, 1.1 million deaths occur a year due to this disease, making it the fourth leading cause of mortality worldwide.