Vaccines are an important public health measure for tiding over the COVID-19 pandemic. Several vaccines have been approved in different countries for emergency use. In India, two vaccines have been currently approved- COVISHIELD (Serum Institute of India (SII)) which is a recombinant simian adenovirus-based vaccine and COVAXIN (Bharat Biotech) which is an inactivated SARS-CoV-2 vaccine. Our current study provides the first post approval safety data on ChAdOx1 nCoV- 19 corona virus vaccine (recombinant) use in healthcare workers in northern India (n=804). Around one half of vaccinees developed adverse events at any time post vaccination with majority of reactions being mild to moderate in severity. AEFIs were seen in 40% participants after first dose and around 16% participants after second dose. This observed reactogenicity is much less compared to 60-88% reactogenicity rate observed with Oxford-AstraZenecas ChAdOx1 vaccine in the UK based population. Individually, fever, injection site pain and headache were the commonly observed AEFIs. Overall, the frequency of systemic events of severity grade 3 was only 0.5% and is much less than the reported rates for other recombinant adenoviral vaccines. The rate of serious AEFIs in our study was only 0.1% (n=1). There was a possibility of this AEFI being an immunization stress related response. No deaths were reported in the vaccinees in our study during the study period. Reactogenicity rate was observed to decrease with age and was higher in females. On the basis of interim findings of this safety study, it may be interpreted that the ChAdOx1 nCoV-19 corona virus vaccine (recombinant) (COVISHIELD, Serum Institute of India) carries a good safety profile overall.
5013663 Canine corona virus vaccine
