ABSTRACT
BACKGROUND AND AIM: our study aimed to investigate the association between anti-SARS-CoV-2 IgG level after two doses of BNT162b2 vaccine and the previously infected/infection-naïve status, age, and gender in a population of health care workers (HCWs). METHODS: all the population of immunocompetent HCWs were vaccinated with two doses of BNT162b2 based on a technical data sheet. SARS-CoV-2 IgG assay was performed 25 to 32 days after the second dose. Anti-SARS-CoV-2 IgG level was used as a categorical variable, since 2080 BAU/ml was the median IgG value. The multivariate logistic regression model included the previously infected/infection-naïve status, age groups, and gender. RESULTS: All HCWs tested were seropositive. The odds ratio (OR) for anti-SARS-CoV-2 IgG> 2080 BAU / ml between previously infected and infection-naïve HCWs was 2.05 [95% CI 1.1-3.8]. Older age groups had lower percentage of HCWs with anti-SARS-CoV-2 IgG> 2080 BAU / mL than younger groups. Finally, no association between gender and IgG level was found. CONCLUSIONS: our study showed an excellent antibody response to vaccination with BNT162b2 after two doses. A significant difference was observed between anti-SARS-CoV-2 IgG level with age and previous SARS-CoV-2 infection status.
Subject(s)
BNT162 Vaccine , COVID-19 , Aged , Antibodies, Viral , COVID-19 Vaccines , Humans , Immunoglobulin G , SARS-CoV-2 , Vaccines, Synthetic , mRNA VaccinesABSTRACT
OBJECTIVE: To determine the incidence of COVID-19 and the duration of sick leave among asymptomatic healthcare workers (HCWs) after vaccination with BNT162b2. METHODS: From October 2020 to March 2021, we determined the incidence of COVID-19 in a cohort of 671 asymptomatic HCWs before and after the vaccination. We also analyzed the days required to obtain a negative RT-PCR result after infection. RESULTS: Prior to vaccination 105 (15.6%) HCWs were positive. Positive cases were reduced to 42 (7.5%) after the vaccination period (Pâ<â0.0001). A negative RT-PCR was observed at the first control in 80% of vaccinated HCWs and only in 37% before vaccination. CONCLUSIONS: Even in case of asymptomatic infection, vaccinated HCWs have a reduced incidence and a shorter period of sick leave than before vaccination, suggesting vaccination impacts on the sustainability of the health system and labor costs.
Subject(s)
COVID-19 Vaccines , COVID-19 , Asymptomatic Infections , BNT162 Vaccine , Health Personnel , Humans , Incidence , SARS-CoV-2 , Sick Leave , Vaccination , Vaccines, SyntheticSubject(s)
Asymptomatic Infections , COVID-19 Vaccines , COVID-19 , Health Personnel , Pandemics/prevention & control , SARS-CoV-2/isolation & purification , COVID-19/immunology , COVID-19/transmission , COVID-19 Nucleic Acid Testing , COVID-19 Testing , Contact Tracing , Family Characteristics , Female , Humans , MaleABSTRACT
The paper wants to present the data of infection of the Health Care Workers of a research and teaching hospital in Milan, Italy. The majority (2554, 55.9%) of 4572 HCWs were tested for SARS-CoV-2 and 8.8% were found positive. Most of the tested workers were women, but we found higher relative frequency of positivity for men, even after adjustment for age, working area, and occupation. The higher frequency of positive tests in the medicine area is probably explained by the higher concentration in that area of COVID-19 patients. Conversely, the low frequency of positive HCWs in intensive care units is probably explained by the diffuse and continuous use of PPD. Our results show that HCWs in a research and teaching hospital in the most hit Region in Italy had a similar pattern of infection as all other HCWs all over the world. The problem of SARS-CoV-2 infections among the hospital personnel HCWs should remind us the concerns about hospital acquired infections both for patients and HCWs.