Bharat Biotech: Adverse events seen in some participants who took Covaxin, reports new study

Nearly a third of the participants of an observational study on the side-effects of Bharat Biotech’s Covid-19 vaccine Covaxin reported adverse events of special interest (AESI), according to a report on SpringerLink, an integrated platform for journals and other materials published by Springer. Researchers found that female adolescents and those with a history of allergy are at a higher risk of AESI after receiving Covaxin, as per the report.

“The majority of the AESI persisted at the 1-year follow-up,” said the study conducted by Sankha Shubhra Chakrabarti and his team at Banaras Hindu University.

Out of 1,024 individuals enrolled, 635 adolescents and 291 adults could be contacted during the 1-year follow-up. According to the study, viral upper respiratory tract infections were reported by 304 (47.9%) adolescents and 124 (42.6%) adults.

New-onset skin and subcutaneous disorders (10.5%), general disorders (10.2%), and nervous system disorders (4.7%) were the common AESIs in adolescents. General disorders (8.9%), musculoskeletal disorders (5.8%), and nervous system disorders (5.5%) were the common AESIs in adults. Menstrual abnormalities were noticed in 4.6% of female participants. Ocular abnormalities and hypothyroidism were observed in 2.7% and 0.6% of participants, respectively.

Among serious AESIs (1%), stroke and Guillain-Barre Syndrome were identified in 0.3% and 0.1% of participants, respectively. Among the participants, adolescents, female individuals and those with a history of allergy and post-vaccination typhoid were at 1.6, 2.8, and 2.8 times higher risk of AESIs, respectively, it said.

The majority of the AESIs persisted at the 1-year follow-up. Female individuals and adolescents with pre-vaccination Covid-19, those with comorbidities, and those with post-vaccination typhoid had 1.6, 2, 2.7 and 3.2 times higher odds of persistent AESIs, respectively.

Adults with comorbidities had more than two times higher odds of AESIs and persistent AESIs, it said. The patterns of adverse events developing after Covaxin differed from those reported with other Covid-19 vaccines, as well as between adolescents and adults.

With the majority of adverse events persisting for a significant period, researchers warrant extended surveillance of Covid-19-vaccinated individuals to understand the course and outcomes of late-onset adverse events.

“Focussed monitoring for persistent AESIs is warranted for individuals with a pre-vaccination history of Covid,” researchers said. “Adults with comorbidities, hypertension, are at a higher risk of AESIs and persistent AESIs after BBV152 administration. The patterns of AESIs developing after Covaxin differ from those seen after Covishield, as well as among different age groups.”