Typhoid conjugate vaccine effectiveness in Malawi: evaluation of a test-negative design using randomised, controlled clinical trial data.

ABSTRACT:

Background

Typhoid conjugate vaccines are being introduced in low-income and middle-income countries to prevent typhoid illness in children. Vaccine effectiveness studies assess vaccine performance after introduction. The test-negative design is a commonly used method to estimate vaccine effectiveness that has not been applied to typhoid vaccines because of concerns over blood culture insensitivity. The overall aim of the study was to evaluate the appropriateness of using a test-negative design to assess typhoid Vi polysaccharide-tetanus toxoid conjugate vaccine (Vi-TT) effectiveness using a gold standard randomised controlled trial database.

Methods

Using blood culture data from a randomised controlled trial of Vi-TT in Malawi, we simulated a test-negative design to derive

SUBMITTER: Liang Y 

PROVIDER: S-EPMC9748309 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature