The Aryavarth Express
Agency (New Delhi): A recent study conducted by researchers at Banaras Hindu University (BHU) revealed that nearly one-third of 926 individuals who received Bharat Biotech’s Covaxin reported ‘adverse events of special interest’ (AESI). The study, which followed participants for one year, found that serious AESIs, including stroke and Guillain-Barre syndrome, were reported in 1% of the cases.
Guillain-Barre syndrome is an autoimmune disorder causing weakness in the nerves of the arms and legs. The study, conducted from January 2022 to August 2023, included 635 adolescents and 291 adults. It noted that nearly 50% of the sample experienced infections during the follow-up period, predominantly viral upper respiratory tract infections.
Bharat Biotech responded to the study by stating that multiple studies have demonstrated Covaxin’s excellent safety track record. The study, published in Springer Nature, comes amid global concerns about vaccine side effects, highlighted by AstraZeneca’s recent admission in a UK court about its Covid vaccine causing rare blood clotting and lowered platelet counts.
Key Findings:
Adolescents: Common AESIs included new-onset skin and subcutaneous disorders (10.5%), general disorders (10.2%), and nervous system disorders (4.7%).
Adults: Common AESIs included general disorders (8.9%), musculoskeletal disorders (5.8%), and nervous system disorders (5.5%).
Women: Menstrual abnormalities were reported by 4.6% of female participants, and ocular abnormalities and hypothyroidism were observed in 2.7% and 0.6% of participants, respectively.
Deaths: Four adult deaths were reported, with stroke being the main cause in two cases and post-COVID-19 rhinocerebral mucormycosis in another. The fourth death involved multiple episodes of unconsciousness post-vaccination, with no identified cause.
The study noted that adults receiving three doses of Covaxin were at a higher risk of AESIs compared to those receiving two doses. The researchers called for extended surveillance of vaccinated individuals to understand the long-term effects of AESIs.
Bharat Biotech highlighted the need for comprehensive data to avoid investigator bias and suggested that all study participants should be followed throughout the study period. The company also stressed the importance of comparing vaccinated and non-vaccinated individuals to accurately assess the safety profile.
The BHU study found that AESI patterns and incidence vary with vaccine type and study population. It compared its findings with another study on the Covishield vaccine, which reported a 14% incidence of AESIs, lower than the one-third rate observed for Covaxin.
The researchers emphasized the need for larger studies to understand the long-term safety of Covaxin, particularly in adults, and to explore ethnicity-related differences in vaccine tolerability. The study’s findings are specific to Covaxin and should not be generalized to other types of vaccines, such as viral vector or mRNA vaccines.