Optimizing the Value of Typhoid Fever Vaccine Immunization Programs



Situation Analysis:

Typhoid fever from a bacterial infection with Salmonella typhi is a significant cause of morbidity and mortality in developing countries where access to clean water and basic sanitation is not universal. Annual incidence is estimated to be 13-27 million cases, with greater than 260,000 deaths annually. Typhoid fever has been a challenging disease to address due to poor diagnostics and the emergence of resistance to antibiotics used to treat the disease. Prevention of typhoid fever through vaccination was recommended by the World Health Organization 15 years ago and two vaccines have been licensed for years. These vaccines have key limitations that limit their use, including a short duration of protection (3-5 years) and effective only in those over two years old. Several typhoid conjugated vaccine (TCV) candidates now in development have demonstrated they can overcome the disadvantages of the current vaccines.

Discovery & Solutions:

SDG’s global health unit, Applied Strategies, developed methodology and analytical models and worked with client-identified experts to assess analysis inputs to determine the potential health impact and cost effectiveness of several TCV candidates with alternative implementation strategies. The insight derived from these analyses helped identify the best TCV introduction plan given our client’s mission and goals. Additional analyses were conducted to better understand health impact in typhoid-endemic countries.

Results and Impact:

Analysis results confirmed that TCVs are very cost-effective and also highlighted that health impact could be doubled if immunization programs were focused on infants in high- and medium-burden countries rather than on infants in high-risk regions of high-burden countries. The analysis was subsequently used to communicate the team’s change in strategy to senior management.