Assessing the Effectiveness of the R21Matrix-M Malaria Vaccine in Children Under 5 in Burkina Faso and Uganda

What this Trial Is About

Researchers are evaluating the real-world effectiveness of the R21Matrix-M malaria vaccine among children under 5 years old in Burkina Faso and Uganda. This observational study aims to understand how well the vaccine works outside of controlled clinical trials, considering factors like dose number, timing, and local malaria transmission levels. The study includes children who seek outpatient care with suspected malaria and compares vaccinated and unvaccinated cases to estimate vaccine effectiveness. Participants receive the R21Matrix-M vaccine through routine national immunization programs, and the study records the number and dates of vaccine doses received. Children are classified based on microscopy blood smear results as either malaria-positive cases or malaria-negative controls. Data on vaccination history, demographic details, malaria prevention use, and clinical information are collected primarily through caregiver questionnaires and health records during an approximately 7- to 8-month recruitment period. During the study, children undergo malaria testing as part of routine care, and researchers use blood smear microscopy to confirm diagnosis. Information on vaccine doses, timing, and other prevention methods is verified using vaccination cards or facility records. The study measures vaccine effectiveness by comparing vaccination odds between cases and controls. The primary outcome is the dose-specific effectiveness against confirmed clinical malaria at enrollment. Additional analyses will explore factors like time since vaccination, dose spacing, transmission intensity, sex, and use of other malaria prevention strategies. Participation lasts through the enrollment episode within the recruitment period.

Assessing Vaccine Effectiveness of R21/Matrix-M Across Malaria Transmission Settings (AVERT)