Booster vaccination and post-COVID-19 condition during the Omicron variant-dominant wave: a large population-based study

Arisa Iba; Mariko Hosozawa; Miyuki Hori; Yoko Muto; Tomomi Kihara; Isao Muraki; Rie Masuda; Nanako Tamiya; Hiroyasu Iso

doi:10.1016/j.cmi.2024.12.002

Booster vaccination and post-COVID-19 condition during the Omicron variant-dominant wave: a large population-based study

Clin Microbiol Infect. 2024 Dec 9:S1198-743X(24)00588-3. doi: 10.1016/j.cmi.2024.12.002. Online ahead of print.

Authors

Arisa Iba¹, Mariko Hosozawa², Miyuki Hori², Yoko Muto², Tomomi Kihara³, Isao Muraki⁴, Rie Masuda⁵, Nanako Tamiya⁶, Hiroyasu Iso²

Affiliations

¹ Institute of Global Health Policy Research, Bureau of International Health Cooperation, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan. Electronic address: [email protected].
² Institute of Global Health Policy Research, Bureau of International Health Cooperation, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan.
³ Institute of Global Health Policy Research, Bureau of International Health Cooperation, National Center for Global Health and Medicine, Shinjuku, Tokyo, Japan; Department of Public Health Medicine, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan; Health Services Research and Development Center, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁴ Public Health, Department of Social and Environmental Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.
⁵ Health Services Research and Development Center, University of Tsukuba, Tsukuba, Ibaraki, Japan.
⁶ Health Services Research and Development Center, University of Tsukuba, Tsukuba, Ibaraki, Japan; Department of Health Services Research, Institute of Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.

PMID: 39662823
DOI: 10.1016/j.cmi.2024.12.002

Abstract

Objectives: The effect of the COVID-19 booster vaccination and the long-term consequences concerning preventing post-COVID-19 condition (PCC) remains unclear. We aimed to investigate the association of COVID-19 booster vaccination dose and vaccination timing before infection with the risk of PCC during the Omicron variant-dominant wave.

Methods: This population-based study included patients confirmed with COVID-19 (extracted from the Health Center Real-time Information-sharing System) aged 20-69 years, who were infected between 1 July and 31 August 2022. We used a self-report questionnaire to evaluate PCC and extracted information on vaccination from the municipal vaccine registry system. We calculated multiple propensity scores for COVID-19 vaccination status (unvaccinated, 1-2 doses and ≥3 doses) to control for baseline population differences. We then used a logistic regression model with inverse probability weighting to analyse the associations between the number of vaccine doses and the risk of PCC. Additionally, we conducted stratified analysis by gender and subgroup analysis for respiratory and neurological symptoms. Multivariable logistic regression was used to analyse the association between vaccination timing and PCC risk, adjusting for vaccination doses.

Results: Of the 7936 participants with COVID-19 (mean age 42.9 years, 4553 women), 940 (11.8%) had at least 1 PCC. Compared with people unvaccinated, those vaccinated ≥3 times before the infection had a lower probability of PCC with the OR of 0.69 (95% CI: 0.53-0.90), although we detected no association with one or two doses. This association was present in women (≥3 doses vs. unvaccinated OR: 0.70, 95% CI: 0.51-0.95) but not in men. Those vaccinated ≥3 times had fewer neurological symptoms compared with those unvaccinated (OR: 0.61, 95% CI: 0.45-0.83); however, no significant association was found for respiratory symptoms.

Discussion: This study suggests that booster vaccination could lower the risk of PCC.

Keywords: Booster vaccine; Japan; Population study; Post-COVID-19 condition; Vaccination effect.