EFFECTIVENESS OF BCG VACCINATION AGAINST SARS-COV-2
Background: Bacillus Calmette-Guerin (BCG) vaccine is weakened Mycobacterium bovis based preparation that provides protective effects and immunotherapy against many ailments and may be tested against SARS-COV-2. Herein, we compare the prevalence of COVID-19 in countries with and without mandatory BCG vaccination program along with a study to examine its incidence in doctors working at quarantine facility with and without history of prior BCG vaccination. Methods: For cross-sectional examination, the data was collated from worldometer.info, BCG World Atlas and COVID-19 stats at National Command and Operation Centre (NCOC), Government of Pakistan accessed on Apr 30, 2021. For a real-time analysis, total of one hundred random male and female doctors working at a COVID-19 healthcare facility in Pakistan were voluntarily selected. Chi-square test was used to perform the statistical analysis with the help of SPSS-22. Results: The prevalence of COVID-19 in countries with and without a mandatory BCG vaccination policy was found to be 5,512 and 75,592 cases per million, respectively, and mortality rates were 98 and 1,435 per million, respectively. Amongst our randomly selected doctors, only 28% of the BCG vaccinated doctors were affected by COVID-19 contrary to 94% of those who were unvaccinated. Conclusions: The incidence of COVID-19 was considerably lower in the doctors with a history of BCG vaccination supported by the evidence that the countries with a universal BCG vaccine policy had a significantly low incidence and lower mortality rate due to COVID-19.
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