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Likelihood of long COVID varies by variant, sex, and vaccination status
Clinical Question
How likely are long COVID symptoms to occur among fully vaccinated health care workers after infections that do not require hospitalization?
Bottom line
Among adult health care workers, this study found that long COVID is less likely in those who have been infected with more recent variants of COVID-19 and in those who have received 3 doses of vaccine. 1b
Reference
Study design: Cohort (prospective)
Funding: Foundation
Setting: Outpatient (any)
Synopsis
This study took place in a network of 9 Italian hospitals from March 2020 to April 2022. Personnel were tested weekly or every other week using PCR for SARS-CoV2, as well as any time they developed symptoms. Long COVID was defined as the persistence of a symptom of the acute infection for more than 4 weeks. Over the study period, 739 of 2560 personnel tested positive for COVID-19 (of whom 89 were asymptomatic) and 229 (31%) developed long COVID. The prevalence of long COVID varied greatly by variant: 42% for the ancestral strain, 36% for the alpha variant, and 16% for the delta or omicron variants. The highest risk group was unvaccinated women. In a multivariate analysis, risk was lower for men (adjusted odds ratio [aOR] 0.65; 95% CI 0.44 - 0.98), persons who received 2 vaccine doses (aOR 0.25; 0.07 - 0.87), and persons who received 3 vaccine doses (aOR 0.16; 0.03 - 0.84). Risk of long COVID was also increased with older age, in persons with allergies, and in persons with an increasing number of comorbidities. The illness trajectory for patients with long COVID (duration and severity of symptoms over time) was not reported.
Reviewer
David C. Slawson, MD
Professor and Vice Chair of Family Medicine for Education and Scholarship
Atrium Health
Professor of Family Medicine, UNC Chapel Hill
Charlotte, NC
Comments
Covid
Reassuring to learn that vaccinated patients are less likely to suffer long term effects from Covid.
long haul covid
risk factors