ABSTRACT
Introduction: To combat the COVID-19 pandemic, a mass vaccination campaign was started in Italy and other European countries on December 27, 2020. The first vaccine available to immunize healthcare workers (HCWs) was the BNT162b2 mRNA COVID-19 vaccine (Comirnaty). While many studies have shown a high antibody response after the second vaccine dose, antibody persistence over the medium-long term has yet to be evaluated.Methods: In this study, the medium-long term persistence of anti-SARS-CoV-2 antibodies was determined in a sample of fully vaccinated HCWs at Bari Policlinico General Hospital, Italy. HCWs who completed the vaccination schedule were screened for anti-SARS-CoV-2 IgG on days 15, 30, 60, 90, and 120 after the second vaccine dose.Findings: At each time point, >99% of the screened HCWs were seroprotected. While the geometric mean titer initially declined over time, by 60 days the titer had stabilized. Older subjects seem to lose IgG faster than younger ones.Interpretations: The immunogenicity conferred by the BNT162b2 mRNA vaccine provides further evidence that it is an essential weapon in efforts to bring the COVID-19 pandemic under control. Accordingly, strict measures should be implemented, ranging from the mandatory vaccination of HCWs to strong incentives aimed at achieving vaccination of the large majority of the general population.Funding: None to declare. Declaration of Interest: The authors declare that they have no competing interests.Ethical Approval: The research protocol was approved by Apulian Epidemiological Observatory.
Subject(s)
COVID-19ABSTRACT
Introduction: To combat the COVID-19 pandemic, a mass vaccination campaign was initiated in Italy on December 27, 2020. The vaccine available to immunize Italian healthcare workers (HCWs) was the BNT162b2 mRNA COVID-19 vaccine (Comirnaty). Many studies have shown the high effectiveness of this vaccine in preventing infection and symptomatic disease in the fully immunized.Methods: This study evaluated the effectiveness of the vaccine against documented SARS-CoV-2 infection and symptomatic diseases in the medium- to long-term. HCWs at Bari Policlinico University-Hospital (Italy) who completed the vaccination schedule were matched with HCWs who had refused vaccination; the two groups were followed-up for 5 months (January–May 2021).Findings: Vaccine effectiveness (VE) against infection was 97·7% (95·4–99·0%) at 14–34 days after the first dose, and 94·8% (87·0–97·8%), 83·0% (65·0–92·0%), and 81·0% (42·0-94·0%) at 14–41, 42–69, and >69 days, respectively, after the second dose. The estimated VE for documented symptomatic disease was 99·2% (96·4–99·8%) at 14–34 days after the first dose and 97·2% (90·3–99·2%), 85·0% (63·0–94·2%), and 88·0% (42·0–97·6%) at 14–41, 42–69, and >69 days, respectively, after the second dose.Interpretations: The demonstrated effectiveness and safety of the BNT162b2 mRNA vaccine over the medium- to long-term provides further evidence that it is an essential weapon in ending the COVID-19 pandemic. Efforts to increase vaccination rates should be strengthened, including mandatory vaccination for HCWs and greater incentives to increase vaccine acceptance by the general population.Funding: None to declare. Declaration of Interest: None to declare. Ethical Approval: The research protocol was approved by Apulian Epidemiological Observatory and all human participants gave written informed consent.
Subject(s)
COVID-19 , Barth SyndromeABSTRACT
BackgroundHealthcare workers (HCW) are at increased risk of being infected with SARS-CoV-2, yet limited information is available on risk factors of infection. MethodsWe pooled data on occupational surveillance of 10,654 HCW who were tested for SARS-CoV-2 infection in six Italian centers. Information was available on demographics, job title, department of employment, source of exposure, use of personal protective equipment (PPE), and COVID-19-related symptoms. We fitted multivariable logistic regression models to calculate odds ratios (OR) and 95% confidence intervals (CI). FindingsThe prevalence of infection varied across centers and ranged from 3.0% to 22.0%, being strongly correlated with that of the respective areas. Women were at lower risk of infection compared to men. Fever, cough, dyspnea and malaise were the symptoms most strongly associated with infection, together with anosmia and ageusia. No differences in the risk of infection were detected between job titles, or working in a COVID-19 designated department. Reported contact with a patient inside or outside the workplace was a risk factor. Use of a mask was strongly protective against risk of infection as was use of gloves. The use of a mask by the source of exposure (patient or colleague) had an independent effect in reducing infection risk.