Journal
INTERNATIONAL JOURNAL OF EPIDEMIOLOGY
Volume 35, Issue 4, Pages 1044-1050Publisher
OXFORD UNIV PRESS
DOI: 10.1093/ije/dyl100
Keywords
vaccine trial; herd immunity; GIS; neighbourhood analysis
Categories
Funding
- NIAID NIH HHS [1R013AI53214-01] Funding Source: Medline
Ask authors/readers for more resources
Objectives The effectiveness of vaccines in populations must consider both direct and indirect protection. This study reanalyses data from a large individually randomized oral cholera vaccine trial that was conducted in rural Bangladesh from 1985 to 1990. A recent analysis of the results of that trial showed that the proportion of people in household clusters who received the vaccine was inversely related to placebo incidence during the first year of surveillance, which was attributed to herd immunity. Methods in this study we measure the relationship between neighbourhood-level oral cholera vaccine coverage and protective efficacy (PE) during a 2 year follow-up period, controlling for known effect modifiers. We link trial data to a household geographic information system to facilitate the neighbourhood-level analysis. Findings Neighbourhood-level PE can be partially explained by vaccine coverage after adjusting for ecological variables. Conclusions The inverse relationship between vaccine coverage and efficacy illustrates that people living in high-coverage areas may be indirectly protected from cholera because people living around them are vaccinated.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available