Dataset Information

The effect of time since measles vaccination and age at first dose on measles vaccine effectiveness - A systematic review.

ABSTRACT:

Background

In settings where measles has been eliminated, vaccine-derived immunity may in theory wane more rapidly due to a lack of immune boosting by circulating measles virus. We aimed to assess whether measles vaccine effectiveness (VE) waned over time, and if so, whether differentially in measles-eliminated and measles-endemic settings.

Methods

We performed a systematic literature review of studies that reported VE and time since vaccination with measles-containing vaccine (MCV). We extracted information on case definition (clinical symptoms and/or laboratory diagnosis), method of vaccination status ascertainment (medical record or vaccine registry), as well as any biases which may have arisen from cold chain issues and a lack of an age at first dose of MCV. We then used linear regression to evaluate VE as a function of age at first dose of MCV and time since MCV.

Results

After screening 14,782 citations, we identified three full-text articles from measles-eliminated settings and 33 articles from measles-endemic settings. In elimination settings, two-dose VE estimates increased as age at first dose of MCV increased and decreased as time since MCV increased; however, the small number of studies available limited interpretation. In measles-endemic settings, one-dose VE increased by 1.5% (95% CI 0.5, 2.5) for every month increase in age at first dose of MCV. We found no evidence of waning VE in endemic settings.

Conclusions

The paucity of data from measles-eliminated settings indicates that additional studies and approaches (such as studies using proxies including laboratory correlates of protection) are needed to answer the question of whether VE in measles-eliminated settings wanes. Age at first dose of MCV was the most important factor in determining VE. More VE studies need to be conducted in elimination settings, and standards should be developed for information collected and reported in such studies.

SUBMITTER: Hughes SL

PROVIDER: S-EPMC6970218 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Publications

The effect of time since measles vaccination and age at first dose on measles vaccine effectiveness - A systematic review.

Hughes Stephanie L SL Bolotin Shelly S Khan Sumaiya S Li Ye Y Johnson Caitlin C Friedman Lindsay L Tricco Andrea C AC Hahné Susan J M SJM Heffernan Jane M JM Dabbagh Alya A Durrheim David N DN Orenstein Walter A WA Moss William J WJ Jit Mark M Crowcroft Natasha S NS

Vaccine 20191112 3

<h4>Background</h4>In settings where measles has been eliminated, vaccine-derived immunity may in theory wane more rapidly due to a lack of immune boosting by circulating measles virus. We aimed to assess whether measles vaccine effectiveness (VE) waned over time, and if so, whether differentially in measles-eliminated and measles-endemic settings.<h4>Methods</h4>We performed a systematic literature review of studies that reported VE and time since vaccination with measles-containing vaccine (MC ...[more]

PMID: 31732326

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Dataset Information

The effect of time since measles vaccination and age at first dose on measles vaccine effectiveness - A systematic review.

Background

Methods

Results

Conclusions

Publications

The effect of time since measles vaccination and age at first dose on measles vaccine effectiveness - A systematic review.

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