Flu Vaccination Fails to Protect Against COVID-19 Infection; A Cross-sectional Study

Background: vaccination is likely to be the final solution to stop the covid-19 pandemic which has been considered as a global public health emergency. influenza and coronavirus have previously demonstrated antigenic cross-reactivity. methods: this cross-sectional study was aimed to evaluate the transmission rate and the severity of coronavirus infection among health care workers with history of previous influenza vaccination. subjects of the study were asked about their demographics, influenza vaccination history prior to pandemic, infection with covid-19, and the severity indicators of the disease. results: influenza vaccination has correlation neither with the prevalence of covid-19 infection rate nor with the severity of the disease process among those who received flu vaccines and those who were not vaccinated. vaccinated and unvaccinated subjects were equal in terms of sex, age, and comorbidities. asthma has not been demonstrated to contribute to the severity of the disease. conclusion: influenza vaccination regardless of the evidence on its antigenic cross reactivity with coronavirus, is not associated with lesser involvement by or any contribution to the severity of the 2019 novel sars-cov2 disease.