Study on the possible use of Vi polysaccharide typhoid fever vaccine to control endemic typhoid fever in Nepal

Abstract

This review of literature was conducted to explore the various aspects of typhoid fever in Nepal and to identify the factors concerned in the possible use of the Vi polysaccharide typhoid fever vaccine in Nepal as the tool for prevention and control. There are hotspots of Typhoid fever in developing countries, urban areas and slums, where poor conditions of safe drinking water and sanitation prevail. The use of currently available typhoid fever vaccines, especially the Vi polysaccharide vaccine has been recommended by World Health Organization to control typhoid fever in endemic areas. However, factors like, the burden and the changing epidemiological pattern of the disease, efficacy of the vaccines, ease for intervention, cost effectiveness, financing, and programmatic issues should be considered in local settings before the introduction of vaccines as a public health tool for prevention. We concluded that the possible use of currently available Vi polysaccharide vaccine to control endemic typhoid fever in Nepal might not have the same positive impact as reported in trials from different Asian countries. The major issues to be considered are emergence of Salmonella Paratyphi A as a major cause of enteric fever, no difference in prevalence of typhoid fever in preschool and school children, similar clinical profiles and severity of typhoid and paratyphoid fever. So, an ideal vaccine that can provide the protection both to typhoid and paratyphoid fever, and the vaccination programs that also includes preschool children would be the best option for Nepal.