• Burden of measles in Nigeria: a five-year review of casebased surveillance data, 2012-2016

      Ibrahim, B.S.; Usman, R.; Mohammed, Y. (NLM (Medline), 2019)
      Introduction: measles is a vaccine preventable, highly transmissible viral infection that affects mostly children under five years. We reviewed surveillance data on measles from Nigeria over a five-year period to highlights its burden and make recommendations for improvements. Methods: we conducted a secondary data analysis of measles specific Integrated Disease Surveillance and Response (IDSR) records of all states in Nigeria over a five-year period. Results: a total of 131,732 cases were recorded between January 2012 and September 2016. Most cases 57,892 (43.95%) were recorded in 2013 while the least 11,061 (8.4%) were recorded in 2012. A total of 817 deaths were recorded, with a case fatality rate (CFR) of 0.62%. The highest CFR (1.43%) was recorded in 2012 while the least CFR (0.44%) was recorded in 2016. Only 8,916 (6.7%) cases were confirmed by laboratory tests. The trend of measles cases followed the same pattern throughout the years under review, with cases peaking at March, then gradually reducing to lowest level at June, which was maintained throughout the rest of the year. States in northern region of Nigeria recorded the highest attack rate (Yobe: 480.29 cases per 100,000 population, Sokoto: 284.63 cases per 100,000 population and Katsina: 246.07 cases per 100,000 population) compared to States in the southern region (Rivers: 11.72 cases per 100,000 population and Akwa Ibom: 13.59 cases per 100,000 population). Conversely, States in the southern region recorded the highest CFR (Ebonyi: 13.43% and Rivers: 3.27%). Conclusion: measles infection remains a burden especially in the northern region of Nigeria. Although measles fatalities declined over the years, laboratory confirmation was sub-optimal. We recommended improvement on routine immunization and strengthening of regional laboratories diagnostic capacities, for successful eradication of measles from Nigeria.
    • Forecasting Demand for the Typhoid Conjugate Vaccine in Low- and Middle-income Countries

      Debellut, F.; Hendrix, N.; Pitzer, V.E. (Oxford University Press, 2019)
      BACKGROUND: The World Health Organization (WHO) released a position paper in March 2018 calling for integration of a novel typhoid conjugate vaccine (TCV) into routine immunization along with catch-up campaigns for children up to age 15. Gavi, the Vaccine Alliance, has committed funding to help resource-constrained countries introduce this vaccine. In this article, the Typhoid Vaccine Acceleration Consortium forecasts demand if WHO recommendations are followed. METHODS: We built a model of global TCV introductions between 2020 and 2040 to estimate the demand of the vaccine for 133 countries. We estimated each country's year of introduction by examining its estimated incidence of typhoid fever, its history of introducing new vaccines, and any knowledge we have of its engagement with typhoid prevention, including intention to apply for Gavi funding. Our model predicted use in routine infant vaccination as well as campaigns targeting varying proportions of the unvaccinated population up to 15 years of age. RESULTS: Between 2020 and 2025, demand will predominantly come from African countries, many receiving Gavi support. After that, Asian countries generate most demand until 2030, when campaigns are estimated to end. Demand will then track the birth cohort of participating countries, suggesting an annual routine demand between 90 and 100 million doses. Peak demand is likely to occur between 2023 and 2026, approaching 300 million annual doses if campaign implementation is high. CONCLUSIONS: In our analysis, target population for catch-up campaigns is the main driver of uncertainty. At peak demand, there is some risk of exceeding presently estimated peak production capacity. Therefore, it will be important to carefully coordinate introductions, especially when accompanied by campaigns targeting large proportions of the eligible population. © The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America.