Unmasking herd protection by an oral cholera vaccine in a cluster-randomized trial.

ABSTRACT:

Background

Several studies have shown that inactivated, whole-cell oral cholera vaccines (OCVs) confer both direct protection on vaccinees and herd protection on populations. Because our earlier cluster-randomized effectiveness trial (CRT) in urban Bangladesh failed to detect OCV herd protection, we reanalysed the trial to assess whether herd effects were masked in our original analysis.

Methods

A total of 267 270 persons were randomized to 90 approximately equal-sized clusters. In 60 clusters persons aged 1 year and older were eligible to receive OCV and in 30 clusters persons received no intervention and served as controls. We analysed OCV protection against severely dehydrating cholera for the entire clusters, as in our original analysis, and for subclusters consisting of

SUBMITTER: Ali M 

PROVIDER: S-EPMC6693801 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature