Likelihood of long COVID varies by variant, sex, and vaccination status

Référence

Azzolini E, Levi R, Sarti R. Association between BNT162b2 vaccination and long COVID after infections not requiring hospitalization in health care workers. JAMA 2022;328(7):676-678.

Sommaire

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.