Post COVID-19 condition after Wildtype, Delta, and Omicron variant SARS-CoV-2 infection and vaccination: pooled analysis of two population-based cohorts

Abstract

Background: Post COVID-19 condition (PCC) is an important complication of SARS-CoV-2 infection, affecting millions worldwide. Further evidence is needed on the risk of PCC after vaccination and infection with newer variants. This study aimed to evaluate the prevalence and severity of PCC across different variants and vaccination histories. Methods: We used pooled data from 1350 SARS-CoV-2-infected individuals from two representative population-based cohorts in Switzerland, diagnosed between Aug 5, 2020, and Feb 25, 2022. We descriptively analysed the prevalence and severity of PCC, defined as the presence and frequency of PCC-related symptoms six months after infection, among vaccinated and non-vaccinated individuals infected with Wildtype, Delta, and Omicron SARS-CoV-2. We used multivariable logistic regression models to assess the association and estimate the risk reduction of PCC after infection with newer variants and prior vaccination. We further assessed associations with the severity of PCC using multinomial logistic regression. To identify groups of individuals with similar symptom patterns and evaluate differences in the presentation of PCC across variants, we performed exploratory hierarchical cluster analyses. Findings: We found strong evidence that vaccinated individuals infected with Omicron had a reduced risk of developing PCC compared to non-vaccinated Wildtype-infected individuals (odds ratio 0.42, 95% confidence interval 0.24-0.68). The risk among non-vaccinated individuals was similar after infection with Delta or Omicron compared to Wildtype SARS-CoV-2. We found no differences in PCC prevalence with respect to the number of received vaccine doses or timing of last vaccination. The prevalence of PCC-related symptoms among vaccinated, Omicron-infected individuals was lower across severity levels. In cluster analyses, we identified four clusters of diverse systemic, neurocognitive, cardiorespiratory, and musculoskeletal symptoms, with similar patterns across variants. Interpretation: The risk of PCC appears to be lowered with infection by the Omicron variant and after prior vaccination. This evidence is crucial to guide future public health measures and vaccination strategies. Study registrations: ISRCTN14990068, ISRCTN18181860

Impairments following COVID-19 infection: Manifestations and investigations of related factors

“…This nding is in line with previous studies showed that the risk of post-COVID complaints are differed as function of vaccinate status. In that, post-COVID complaints are more common in non-vaccinated individuals compared to vaccinated individuals 45,47,48,49,50,51,52,53 . In the current study, been hospitalized didn't contribute to the explained variances in post-COVID impairments.…”

“…It is well established that early variants of SARS-CoV-2 in prior waves appeared to cause more severe acute illness than later variants 43,44 . Moreover, recent studies showed that the prevalence and pro le associated with post-COVID condition vary across different SARS-CoV-2 variants 44,45,46 . It is therefore reasonable to conclude that those infected in the early waves of pandemic in Sweden continue to be a vulnerable group to have more severe complaints due to COVID-19 infection and in need of support.…”

Clinical Manifestations of Infections with the Omicron Sub-Lineages BA.1, BA.2, and BA.5: A Retrospective Follow-Up Analysis of Public Health Data from Mecklenburg-Western Pomerania, Germany

“…In previous waves, including the Delta variant and those preceding Omicron, a significant number of individuals were not vaccinated. However, vaccination, particularly booster shots, plays a crucial role in providing protection against severe Omicron infections and the need for hospitalization [ 25 , 26 , 27 , 28 ]. Nevertheless, the vaccination data within our study are limited, given the relatively high number of unreported cases.…”

Lower prevalence of Post-Covid-19 Condition following Omicron SARS-CoV-2 infection

“…Likewise, prevalence of at least one possible PCC-related symptom was similar between both groups. Studies have shown a partial protection of the primary course compared to unvaccinated cases for pre-Omicron variants (8,30,31) and for Omicron (32). Research on the effect of the booster is limited but one study shows a lower association with PCC for threedose vaccinated Omicron cases compared to two-dosed (23).…”