ABSTRACT
In this study,we used publicly available data from the Centrum e-Zdrowia (CeZ) Polish Databank proposing a possible correlation between influenza vaccination and mortality due to COVID-19. We limited our search to the patients with positive COVID19 laboratory tests from 1 January 2020 to 31 March 2021 and who filled a prescription for any influenza vaccine during the 2019-2020 influenza season. In total, we included 116,277 patients and used a generalized linear model to analyze the data.We found out that patients aged 60+ who received an influenza vaccination have a lower probability of death caused by COVID-19 in comparison to unvaccinated, and the magnitude of this difference grows with age. For people below 60 years old, we did not observe an influence of the vaccination. Our results suggest a potential protective effect of the influenza vaccine on COVID-19 mortality of the elderly. Administration of the influenza vaccine before the influenza season would reduce the burden of increased influenza incidence, the risk of influenza and COVID19 coinfection and render the essential medical resources accessible to cope with another wave of COVID-19. To our knowledge, this is the first study showing a correlation between influenza vaccination and the COVID-19 mortality rate in Poland.
ABSTRACT
OBJECTIVES: The disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), termed COVID-19, is asymptomatic or mild in most cases. These patients do not need treatment in hospital and can be isolated at home. To date, most studies have been conducted among inpatients with severe COVID-19. In this study, the authors surveyed patients with mild COVID-19 who remained in home isolation, and analyzed the sources and occupational risk factors for SARS-CoV-2 infections. MATERIAL AND METHODS: This cross-sectional study was carried out on April 17-18, 2020, among patients infected with SARS-CoV-2 who remained in home isolation in Poland. Data were acquired through a structured interview that included questions about the isolation course, symptoms, comorbidities, infection source, household characteristics, occupation, and workplace. Data were presented with descriptive statistics. RESULTS: Of the 4878 patients in home isolation, the authors were able to contact 3313. Of them, 1191 patients declined their invitation, and 2122 agreed to take part. The median age of the patients included in the study was 50 years; 59% were female. Most patients (92%) had not been abroad before the infection. More than half (55%) knew how they became infected; of them, 75% became infected at work. Of all patients, 70% were occupationally active. Nearly half of the occupationally active patients (48%) worked in healthcare, 3% worked in public administration or defense, 3% worked in transportation, and 2% worked in education. Sixty-five percent of the occupationally active patients worked in companies with >100 employees. CONCLUSIONS: Most of the patients with COVID-19 in home isolation in Poland were occupationally active, wherein the majority of people who were aware of the source of SARS-CoV-2 infection worked in healthcare. As most of the infected patients worked in companies with >100 employees, which is not a Polish employment pattern, the authors expect that smaller companies may have a lower risk of SARS-CoV-2 infections. Int J Occup Med Environ Health. 2020;33(6):781-9.