Impact of rotavirus vaccination in Malawi from 2012 to 2022 compared to model predictions

作者：Virginia E. Pitzer, Latif Ndeketa, Ernest O. Asare, Daniel Hungerford, Benjamin A. Lopman, Khuzwayo C. Jere, Nigel A. Cunliffe · 发表于：npj Vaccines · 年份：2024 · DOI：10.1038/s41541-024-01008-6 · 被引用次数：9 · 研究领域：Viral gastroenteritis research and epidemiology、Animal Virus Infections Studies、Hepatitis Viruses Studies and Epidemiology

Rotarix® vaccine was introduced into the Malawi national immunization program in October 2012. We analyzed data on children <5 years old hospitalized with acute gastroenteritis from January 2012 to June 2022, and compared to pre-vaccination data from 1997 to 2009. We estimated vaccine coverage before, during, and after the COVID-19 pandemic using data from rotavirus-negative children. We compared the observed weekly number of rotavirus-associated gastroenteritis (RVGE) cases by age to predictions from a previously developed mathematical model to estimate overall vaccine effectiveness. The number of RVGE and rotavirus-negative acute gastroenteritis cases declined substantially following vaccine introduction. Vaccine coverage among rotavirus-negative controls was >90% with two doses by July 2014, and declined to a low of ~80% in October 2020 before returning to pre-pandemic levels by July 2021. Our models captured the post-vaccination trends in RVGE incidence. Comparing observed RVGE cases to the model-predicted incidence without vaccination, overall effectiveness was estimated to be modest at 36.0% (95% prediction interval: 33.6%, 39.9%), peaking in 2014, and was highest in infants (52.5%; 95% prediction interval: 50.1%, 54.9%). Our mathematical models provide a validated platform for assessing strategies to improve rotavirus vaccine impact in low-income settings.