The Severity of Breakthrough Infections Post-COVID-19 Vaccination in Healthcare and Public Sector in South India

Abstract

Background: Despite massive vaccination programs implemented to abate COVID-19, breakthrough infections among the vaccinated individuals continue to be a source of worry. Aims and Objective: Therefore, our study aimed to investigate the severity of breakthrough and nonbreakthrough infections of SARS-CoV-2 post-COVID-19 vaccinations among health-care workers, COVID-19 frontline warriors, and the general population in South India. Materials and Methods: A survey was jointly conducted by Jothydev's Diabetes Research Centre and Sree Gokulam Medical College and Research Foundation (Thiruvananthapuram, Kerala, India), to assess the severity of nonbreakthrough and breakthrough infections of COVID-19 after vaccination, especially among health-care workers across South India. Results: Of the 225 vaccinated individuals who responded to the survey, 89.3% were vaccinated with Covishield, 8.9% were vaccinated with Covaxin, and 1.7% with other vaccines. One hundred and fifty-three respondents to the survey had COVID-19 infections. Of these, 82 (53.6%) COVID-19 infections were observed in the health care workers (partially and fully vaccinated) and other COVID-19 frontline warriors. One hundred and forty-two people who developed COVID-19 were vaccinated with Covishield, in which 55 (38.7%) developed COVID-19 after the first dose and 87 (61.3%) developed it after the second dose of vaccination. In the Covaxin group, six people (60%) were affected with COVID-19 after the first dose and 4 (40%) people after the second dose. Only one person out of the four vaccinated with other vaccines developed a breakthrough infection. 65 (72.9%) of the individuals vaccinated with Covishield and 2 (50%) of the individuals vaccinated with Covaxin, and one from other categories of vaccines had reported breakthrough infections, infections occurring ≥14 days after completing the recommended doses of COVID-19 vaccinations. Preexisting comorbidities in the people vaccinated with Covishield. Breakthrough infections included in people with diabetes (n = 14), diabetes and high blood pressure (n = 9), asthma (n = 2), and other diseases including (lung disease, malignancy, kidney diseases, and combined comorbidities) (n = 11), and one person with diabetes in Covaxin vaccinated with one person with diabetes and high blood pressure in the other vaccines group. Breakthrough infections cases (52.3%) were mild to moderate (44.5%) and did not require hospitalization. Conclusion: The incidence of severe or critical COVID-19 illness remained low in fully vaccinated patients, even among patients with comorbidities. Nevertheless, the public should follow strict COVID-19 preventive measures, regardless of vaccination status, to reduce transmission and exposure among persons who might not have achieved protective immunity after vaccination.