Breakthrough Infection of Covid-19 in Vaccinated Healthcare Workers at Dhulikhel Hospital and its Associated Factors

With the massive outbreak of pneumonia reported in Wuhan, China in December 2019, the disease was named as Coronavirus disease 2019 (COVID-19). With the declaration of pandemic of COVID-19 on 11th March 2020, caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV2), it has already affected millions of people worldwide. During the early stages of the pandemic, it was thought that SARS-CoV-2 transmission would be slowed by herd immunity because of spontaneous infection, vaccination, or both. Since the pathophysiology and effective immunity gained through vaccination is still not known clearly, we cannot anticipate the protective immune response and breakthrough infection in vaccinated population. COVID-19 breakthrough infection is defined as the detection of SARS-CoV-2 RNA or antigen in a respiratory specimen collected from a person ≥14 days after receipt of all recommended doses of an approved COVID-19 vaccine.6 Serum neutralizing antibodies rapidly appear after SARS CoV-2 infection and vaccination and continue to remain for several months. The level of neutralizing antibodies helps in predicting the level of immune protection against COVID-19. In Nepal, the COVID-19 vaccine rollout was initiated on January 27, 2021, with the administration of Covishield targeting healthcare workers and high-risk groups. At Dhulikhel Hospital-Kathmandu University Hospital, the first dose of vaccination of all the healthcare workers was conducted in January 2021 and the second dose of vaccination was given in April 2021. Around 99% of staff have been vaccinated with a second dose of Covishield (Serum Institute, India) or Vero cell (Sinopharm, China) till date. Remaining 1% are unvaccinated due to pregnancy or active infection with COVID-19. Healthcare workers are at high- risk of being infected with COVID-19 due to occupational exposure to COVID-19 virus at their workplace.

Study Duration: 12/2021-Present

To assess the breakthrough infection of COVID-19 in vaccinated healthcare workers and its associated factors

Breakthrough infection was present in more than one third of health care workers, which was high among the health care workers who were directly involved in patient care. It was found that vaccinations significantly decrease severe diseases and the need for hospitalizations.

Team Members:

Principal Investigator(s): Dr. Dipesh Tamrakar

Co-Investigator(s): Dr. Rajeev Shrestha, Dr. Puspanjali Adhikari, Nishan Katuwal

Project Coordinator: Nishan Katuwal

Research Assistant(s): Manisha Banjara, Nisha Shrestha, Anil Khanal, Aastha Shrestha, Sony Shrestha

Supported by: Nepal Health Research Council (NHRC)