J 2022

Protection by Vaccines and Previous Infection Against the Omicron Variant of Severe Acute Respiratory Syndrome Coronavirus 2

ŠMÍD, Martin, Luděk BEREC, Lenka PŘIBYLOVÁ, Ondřej MÁJEK, Tomáš PAVLÍK et. al.

Basic information

Original name

Protection by Vaccines and Previous Infection Against the Omicron Variant of Severe Acute Respiratory Syndrome Coronavirus 2

Authors

ŠMÍD, Martin (guarantor), Luděk BEREC, Lenka PŘIBYLOVÁ (203 Czech Republic, belonging to the institution), Ondřej MÁJEK (203 Czech Republic, belonging to the institution), Tomáš PAVLÍK (203 Czech Republic, belonging to the institution), Jiří JARKOVSKÝ (203 Czech Republic, belonging to the institution), Jakub WEINER, Tamara BARUSOVÁ and Jan TRNKA

Edition

The Journal of Infectious Diseases, Oxford University Press, 2022, 0022-1899

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

30303 Infectious Diseases

Country of publisher

United States of America

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 6.400

RIV identification code

RIV/00216224:14110/22:00126263

Organization unit

Faculty of Medicine

DOI

UT WoS

000805341600001

Keywords in English

COVID-19; postinfection immunity; vaccine effectiveness; SARS-CoV-2; Omicron variant; hospitalization

Tags

Tags

International impact, Reviewed
Změněno: 14/3/2023 12:30, Mgr. Tereza Miškechová

Abstract

V originále

Background The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evades immunity conferred by vaccines and previous infections. Methods We used a Cox proportional hazards model and a logistic regression on individual-level population-wide data from the Czech Republic to estimate risks of infection and hospitalization, including severe states. Results A recent (≤2 months) full vaccination reached vaccine effectiveness (VE) of 43% (95% confidence interval [CI], 42%–44%) against infection by Omicron compared to 73% (95% CI, 72%–74%) against Delta. A recent booster increased VE to 56% (95% CI, 55%–56%) against Omicron infection compared to 90% (95% CI, 90%–91%) for Delta. The VE against Omicron hospitalization of a recent full vaccination was 45% (95% 95% CI, 29%–57%), with a recent booster 87% (95% CI, 84%–88%). The VE against the need for oxygen therapy due to Omicron was 57% (95% CI, 32%–72%) for recent vaccination, 90% (95% CI, 87%–92%) for a recent booster. Postinfection protection against Omicron hospitalization declined from 68% (95% CI, 68%–69%) at ≤6 months to 13% (95% CI, 11%–14%) at >6 months after a previous infection. The odds ratios for Omicron relative to Delta were 0.36 (95% CI, .34–.38) for hospitalization, 0.24 (95% CI, .22–.26) for oxygen, and 0.24 (95% CI, .21–.28) for intensive care unit admission. Conclusions Recent vaccination still brings substantial protection against severe outcome for Omicron.