Long COVID symptoms in hospital employees after post-vaccination SARS-CoV-2 infection in Austria: A study on self-reported incidence and associated factors.

PURPOSE: Post acute sequelae of SARS-CoV-2 infection are defined by persistence or re-occurrence of symptoms six to 12 weeks after SARS-CoV-2 infections. METHODS: Twice vaccinated hospital employees after mild to moderate post-vaccination SARS-CoV-2 infection completed a questionnaire on the incidence of general, respiratory, neuropsychiatric, dermatological and gastrointestinal symptoms, experienced during their acute infection and eight weeks after recovery. Post acute sequelae of SARS-CoV-2 infection were analysed in relation to socio-demographic-, health-, virus- and acute infection-related characteristics. RESULTS: 73 participants, 25 women and 48 men with a mean age of 40.9 years, with a post-vaccination SARS-CoV-2 infection completed the survey. Out of these 93 % reported at least one symptom at time of initial SARS-CoV-2 infection, 31.5 %, predominantly women, reported post acute sequelae at least eight weeks after the acute infection stage. Fatigue, dysgeusia and dysosmia, headache or difficulty concentrating and shortness of breath during acute infection, BMI> 25 and pre-existing pulmonary disorders were associated with post acute sequelae of SARS-CoV-2 infection. Participants with initially more than five symptoms were four times more likely to report post acute sequelae. CONCLUSION: It is suggested that the multiplicity of symptoms during acute SARS-CoV-2 infections increases the risk for post acute symptoms.

Postvaccination infections among staff of a tertiary care hospital after vaccination with severe acute respiratory syndrome coronavirus 2 vector and mRNA-based vaccines.

OBJECTIVES: The identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigen or RNA in respiratory specimens ≥14 days after administration of all recommended doses of authorized coronavirus disease 2019 (COVID-19) vaccines is defined as breakthrough infection. In the present investigation, mRNA and vector-based SARS-CoV-2 vaccines were analysed with respect to postvaccination infections in vaccinated hospital employees. METHODS: A total of 8553 staff members were vaccinated with BNT162b2 (47%) or ChAdOx1-S (53%) between January and May 2021. In a retrospective observational cohort study, incidence of SARS-CoV-2 postvaccination infections was analysed in relation to demographic data, viral load, virus variants, vaccine brand and vaccination status at time of positive PCR test (fully vaccinated: ≥14 days since second dose; partially vaccinated: >21 days since first, but <14 days after second dose; insufficiently vaccinated: <22 days since first dose). RESULTS: Within the follow-up period, ending on 31 July 2021, person-time at risk-adjusted monthly rates for SARS-CoV-2 postvaccination infections were 0.18% (BNT162b2) and 0.57% (ChAdOx1-S) for insufficiently vaccinated, 0.34% (BNT162b2) and 0.32% (ChAdOx1-S) for partially vaccinated and 0.06% (BNT162b2) and 0.04% (ChAdOx1-S) for fully vaccinated participants. The two vaccine types did not differ with respect to hazard ratios for any of the respective postvaccination infection types. No cases of COVID-19-related hospitalizations or deaths were reported. Genotyping of positive PCR specimens revealed 42 variants of concern: B.1.1.7 (Alpha variant; n = 34); B.1.351 (Beta variant; n = 2), B.1.617.2 (Delta variant; n = 6). CONCLUSIONS: BNT162b2 and ChAdOx1-S are both effective in preventing breakthrough infections; however, it seems important, that all recommended vaccine doses are administered.