Nearly a third of the participants of a study on the side-effects of Bharat Biotech's COVID-19 vaccine Covaxin reported adverse events of special interest (AESI), ET reported. During the one-year follow-up of 635 adolescents and 291 adults, viral upper respiratory tract infections were reported by 304 adolescents and 124 adults. Menstrual abnormalities were noticed in 4.6% of female participants.