Identifying and Alleviating Bias Due to Differential Depletion of Susceptible People in Postmarketing Evaluations of COVID-19 Vaccines

Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health 2022. This work is written by US Government employees and is in the public domain in the US..

Recent studies have provided key information about SARS-CoV-2 vaccines' efficacy and effectiveness (VE). One important question that remains is whether the protection conferred by vaccines wanes over time. However, estimates over time are subject to bias from differential depletion of susceptible individuals between vaccinated and unvaccinated groups. We examined the extent to which biases occur under different scenarios and assessed whether serological testing has the potential to correct this bias. By identifying nonvaccine antibodies, these tests could identify individuals with prior infection. We found that in scenarios with high baseline VE, differential depletion of susceptible individuals created minimal bias in VE estimates, suggesting that any observed declines are likely not due to spurious waning alone. However, if baseline VE was lower, the bias for leaky vaccines (which reduce individual probability of infection given contact) was larger and should be corrected for by excluding individuals with past infection if the mechanism is known to be leaky. Conducting analyses both unadjusted and adjusted for past infection could give lower and upper bounds for the true VE. Studies of VE should therefore enroll individuals regardless of prior infection history but also collect information, ideally through serological testing, on this critical variable.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:191

Enthalten in:

American journal of epidemiology - 191(2022), 5 vom: 24. März, Seite 800-811

Sprache:

Englisch

Beteiligte Personen:

Kahn, Rebecca [VerfasserIn]
Schrag, Stephanie J [VerfasserIn]
Verani, Jennifer R [VerfasserIn]
Lipsitch, Marc [VerfasserIn]

Links:

Volltext

Themen:

Bias
COVID-19 Vaccines
Epidemics
Journal Article
Research Support, N.I.H., Extramural
SARS-CoV-2
Vaccines
Waning

Anmerkungen:

Date Completed 09.05.2022

Date Revised 11.05.2024

published: Print

Citation Status MEDLINE

doi:

10.1093/aje/kwac015

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM336160224