COVID-19 VACCINE BREAKTHROUGH INFECTIONS AMONG HEALTH CARE WORKERS IN MILITARY INSTITUTES OF PAKISTAN - TILL 30TH JUNE 2021

ABSTRACT Objective: To measure incidence of COVID-19 vaccine breakthrough infections among health care workers vaccinated with both doses of Sinopharm Vaccine. Study Design: Prospective cohort study. Place and Duration of Study: All Military Institutes of Pakistan, from Feb to Jun 2021. Methodology: Detailed surveillance mechanism was developed before the start of Health Care Workers vaccination in Pakistan Military to report any PCR positive COVID-19 infection post vaccination. Among 39512 health care workers vaccineted with both doses of COVID-19 vaccine; those who developed COVID-19 infection ≥14 days post 2nd dose were included in the study. Total 124 participants till 30 Jun 2021 fulfilled the criteria of COVID-19 vaccine breakthrough infection and were analyzed. Results: Mean age of the participants was 38.8 ± 11 years. Males were 69.4% while females were 30.6%. Median duration from 2 nd dose to development of COVID-19 vaccine breakthrough infection was 36.5 days (IQR, 26-62). Asymptomatic/mild infections were reported among 94.4% and only 5.6% had moderate disease. No severe/critical disease requiring oxygen supplementation or ventilator support was observed. Recovery rate was 100% with no mortality. There was no significant statistical association of age, gender, job category with COVID-19 vaccine breakthrough infection (p>0.05). Conclusion: Vaccines remain an important weapon in the battle against COVID-19. No vaccine is 100% effective against all strains of COVID-19; however among the completely vaccinated health care workers less severe disease was observed. There was no mortality.