The Seroprevalence of SARS-CoV-2 Antibodies among HealthCare Workers in University Hospital in Krakow before the Era of Vaccination

Abstract

Background: Knowledge of occupational health is crucial to the safety of healthcare workers in the pandemic period. The aim of our study was the rating of SARS-CoV-2 seroprevalence in connection with selected demographic, social, and organizational factors, as well as the identification of key elements determining the safety of HCWs and patients of the University Hospital in Krakow. Methods: This was a non-interventional, uncontrolled, open, single-center, cross-sectional online survey on the preparedness for the COVID-19 epidemic and the seroprevalence of medical and non-medical HCWs and students. Serum specimens from 1221 persons were tested using an immunoassay analyzer based on the ECLIA technique for the anti-SARS-CoV-2 antibodies IgM + IgG. Results: The total seroprevalence was 42.7%. In medical students it was 25.2%, while in physicians it was 43.4% and in nurses/midwives it was 48.1%. Of those who tested positive, 21.5% did not know their serological status. The use of personal protective equipment did not have any significant impact on the result of testing for anti-SARS-CoV-2 antibodies. The risk of developing the disease was not influenced by sex, professional work experience, workplace, or intensity of contact with the patient. Among the studied elements, only care of COVID-19 patients significantly increased the risk. The protective factor was starting work between the waves of the epidemic (June–September 2020). Conclusions: PPE is only one element of infection prevention and control—without other components, such as hand hygiene, it can be dangerous and contribute to self-infection. It is also very important to test healthcare workers. Not being aware of the COVID-19 status of HCWs poses a threat to other staff members, as well as patients and the family and friends of the infected. Thus, extreme caution should be applied when employing respirators with exhalation valves during the COVID-19 pandemic.

SARS-CoV-2 antibody response after mRNA vaccination in healthcare workers with and without previous COVID-19, a follow-up study from the University Hospital in Krakow, Poland

“…In our study, up to 41.1% of HCWs had positive antibody test results, before the vaccinations started which may suggest that their exposure to the virus was indeed very high, as it was previously described ( 8 ). According to Afzal et al.…”

“…only 0.028% results of ECLA test can be false positives ( 21 ). Somewhat, the obtained results may be explained by the potentially greater intensity of the contact between HCWs and patients in Polish hospitals than in other countries ( 8 ). Quite recently, our colleagues from the Polish National Institute of Public Health showed in their multicenter study that the seroprevalence for Polish HCWs working in hospitals but also in ambulatory practices before the vaccination campaign was 25.2% ( 22 ).…”

“…Participants could choose different symptoms which were stratified into 3 groups: asymptomatic infection (no symptoms); mild infection (fever, cough, fatigue, loss of smell or taste, body aches and pains, headache, sore throat, runny or stuffy nose, digestive symptoms including nausea, vomiting, or diarrhea) or severe (shortness of breath and difficulty breathing, pneumonia). The methods and population studied in the first stage of the study have previously been described in detail ( 8 ). In the follow-up survey, participants were also asked about vaccination, the type of COVID-19 vaccine and the number of doses received, and side effects after each dose.…”

“…In fact, meta-analyses showed that a significant number of HCWs were reported to be infected with COVID-19 during the first 6 months of the COVID-19 pandemic, 15.1% of infected subjects required hospitalization and death occurs in 1.5% of infected patients ( 6 , 7 ). The contact with infected individuals both inside and outside the hospital was associated with higher risk of SARS-CoV-2 infection among HCWs ( 8 , 9 ) Fortunately, COVID-19 cases among health care workers decreased rapidly with the introduction of the anti- COVID-19 vaccination ( 10 , 11 ).…”

Seroprevalence of SARS-CoV-2 Among Healthcare Workers in Two Governorates Hospitals, Yemen

“…Over the rst 3 years of the pandemic variable seroprevalence rates among HCWs have been reported re ecting the differences in the point of time and the geographical region. In early studies of the pandemic mainly in the year 2020, a COVID-19 seroprevalence rate of 14.8% was reported among HCWs in Saudi Arabia [10], 19% in Turkey [11], 25.6% in Egypt [12], 27% in New York City [13], 42.7% in Poland [14], 45% in Nigeria, [15], and 48% in Ethiopian [16]. As of late 2021 higher seroprevalence rates have been reported among HCWs as it reached 89.3% in Hong Kong [17], and 94.5% in Delhi India [18].…”