COVID-19 vaccination and breakthrough infections among healthcare workers: an online survey

Ramesh Masthi, Gowri Hebbar


Background: COVID-19 vaccinations were started in India among health care workers in January, 2021. These vaccinations provide protective immunity against the infection but may not completely exclude the possibility of contracting the infection. The objective was to assess the risk of contracting COVID-19 disease following vaccination; to describe the adherence to COVID appropriate behavior by vaccinated individuals.

Methods: A cross-sectional study was conducted using an online questionnaire. The subjects selected were health care workers, medical students and other frontline workers. The sample size was 393. The risk of COVID-19 following vaccination was assessed against various factors like age, type of vaccination, status of vaccination, pre-existing comorbidities etc.

Results: Out of the 393 vaccinated subjects, 57 (14.5%) acquired COVID-19 breakthrough infection. Majority of these individuals (75.4%) experienced mild symptoms. All vaccinated individuals were protected from severe COVID-19 disease. Most vaccinated individuals continued to strictly adhere to COVID appropriate behavior i.e., masks (97.0% and 98.0%), sanitized hands (93.0% and 98.0%) and maintain social distanced (91.6% and 86%) in both fully and partially vaccinated groups following vaccination.

Conclusions: One tenth of the subjects were infected with COVID-19 following vaccination. Most experienced mild symptoms and risk of severe disease was significantly reduced.  There was no significant association between the type of vaccine administered and risk of infection.


Breakthrough infection, COVID appropriate behaviour, COVID-19 vaccine

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