Reduction in COVID-19 prevalence in healthcare workers in a university hospital in southern Brazil after the start of vaccination

Introduction: The quick spread of SARS-CoV-2 led to the development of vaccines that are capable of reducing infection and the number of more severe COVID-19 cases. Aim: To assess COVID-19 prevalence among healthcare workers (HCWs) after vaccination against SARS-CoV-2. Methods: This was a cross-sectional study on the prevalence of COVID-19 diagnosis among 7523 HCWs vaccinated against SARS-CoV-2 with CoronaVac and ChAdOx1 nCoV-19 in a university hospital, in southern Brazil, between January 18 and March 18, 2021.The variables evaluated were: sex, age, work area, role, source of infection, previous diagnosis of COVID-19, date of vaccine administration, type of vaccine, and need for hospitalization. The statistical analysis used Poisson regression and Fisher's exact test with SPSS software version 25, and a level of significance set at 5%. Results: 813 vaccinated HCWs showed symptoms suggestive of COVID-19, of whom 35.4% (288) had a detectable result after undergoing RT-PCR for SARS-CoV-2. There was a reduction of 62% in new cases of COVID-19 among HCWs in the institution 7 weeks after the start of vaccine rollout. Conclusion: Our data suggest that the vaccines used by the institution reduced the number of COVID-19 cases among healthcare workers, demonstrating the effectiveness of the vaccines

Heart failure secondary to myocarditis after SARS-CoV-2 reinfection : a case report

Introduction: Cardiac involvement in COVID-19 can range from mild damage to severe myocarditis. The precise mechanism by which COVID-19 causes myocardial injury is still unknown. Myocarditis following administration of COVID-19 vaccines, especially those based on mRNA, has also been described. How- ever, no reports of heart failure following reinfection with SARS-CoV-2 in patients immunized with an inactivated vaccine have been identified. Case description: The patient was a 47-year-old male construction worker of African descent, with type II diabetes and a history of infection by SARS-CoV-2 in December 2020 and May 2021, confirmed by RT-PCR. He received two doses of an inactivated vaccine against COVID-19. Between the two COVID-19 episodes with positive RT-PCR, he had two episodes of bacterial lung infection. After the second episode of SARS-CoV-2 infection, he was diagnosed with severe heart failure as a sequela of myocarditis. Conclusion: It is essential to perform a thorough follow-up after infection with SARS-CoV-2 since, even with proper immunization, it is possible that the patient was reinfected and suffered severe cardiac se- quelae as a consequence. The hypothesis of an etiology associated with the use of an inactivated vaccine against COVID-19, with a potential immune enhancement mechanism following reinfection with SARS-CoV-2, cannot be rejected