A cost-benefit analysis of typhoid fever immunization programmes in an Indian urban slum community.

Many economic analyses of immunization programmes focus on the benefits in terms of public-sector cost savings, but do not incorporate estimates of the private cost savings that individuals receive from vaccination. This paper considers the implications of Bahl et al.'s cost-of-illness estimates for typhoid immunization policy by examining how community-level incidence estimates and information on distribution of costs of illness among patients and the public-health sector can be used in the economic analysis of vaccination-programme options. The findings illustrate why typhoid vaccination programmes may often appear to be unattractive to public-health officials who adopt a public budgetary perspective. Under many plausible sets of assumptions, public-sector expenditure on typhoid vaccination does not yield comparable public-sector cost savings. If public-health officials adopt a societal perspective on the economic benefits of vaccination, there are many situations in which different vaccination programmes will make economic sense. The findings show that this is especially true when public decision-makers recognize that (a) the incidence of typhoid fever is underestimated by blood culture-positive cases and (b) avoided costs of illness represent a significant underestimate of the actual economic benefits to individuals of vaccination.

The role of epidemiology in the introduction of vi polysaccharide typhoid fever vaccines in Asia.

Despite the availability of at least two licensed typhoid fever vaccines--injectable sub-unit Vi polysaccharide vaccine and live, oral Ty21a vaccine--for the last decade, these vaccines have not been widely introduced in public-health programmes in countries endemic for typhoid fever. The goal of the multidisciplinary DOMI (Diseases of the Most Impoverished) typhoid fever programme is to generate policy-relevant data to support public decision-making regarding the introduction of Vi polysaccharide typhoid fever immunization programmes in China, Viet Nam, Pakistan, India, Bangladesh, and Indonesia. Through epidemiological studies, the DOMI Programme is generating these data and is offering a model for the accelerated, rational introduction of new vaccines into health programmes in low-income countries. Practical and specific examples of the role of epidemiology are described in this paper. These examples cover: (a) selection of available typhoid fever vaccines to be introduced in the programme, (b) generation of policy-relevant data, (c) providing the 'backbone' for the implementation of other multidisciplinary projects, and (d) generation of unexpected but useful information relevant for the introduction of vaccines. Epidemiological studies contribute to all stages of development of vaccine evaluation and introduction.

Reassessment of frequency of occurrence of typhoid fever and cost efficacy analysis of antibiotic therapy.

Typhoid fever has assumed importance due to the increased incidence of drug resistance in India. The exact magnitude of the problem is not accurately known. The objective of this study was to collect retrospectively the data on the incidence and frequency of typhoid fever among hospital admissions at St. Johns Medical College Hospital (SJMCH), Bangalore during the year 1987 to 1992 and also to study the sensitivity pattern and the use of antibiotics. The study was also aimed at comparison of immunogenicity and tolerance of conventional vaccine to the newer polysaccharide vaccine. It was found that the incidence of typhoid fever showed change from epidemic to endemic situation with outbreaks of epidemics. Sensitivity pattern also showed change during the same period and antibiotic resistance was increasingly demonstrated from 1989. Cost per patient and total cost to the hospital due to increased admissions also showed progressive increase. The polysaccharide vaccine (recently made available in India) had very low adverse reaction profile with higher immunogenicity as compared to conventional vaccine. Its single dose effect with long lasting immunity indicates it probable usefulness in the eradication of disease.