A recent study has highlighted that adolescent females and individuals with a history of allergies are at a higher risk of adverse events of special interest (AESI) following the administration of Covaxin, India’s first indigenous COVID-19 vaccine. Published on SpringerLink, the observational research conducted by Banaras Hindu University found that nearly one-third of the participants experienced AESIs post-vaccination.

According to The Economic Times, the study enrolled 1,024 individuals, including 635 adolescents and 291 adults, who were monitored over a year-long follow-up period. The findings revealed that viral upper respiratory tract infections affected 47.9% of adolescents and 42.6% of adults.

What is AESI?

Adverse events of special interest (AESI) refer to specific conditions or events that may occur following immunization and could potentially be causally linked to the vaccine. Examples of AESIs include anaphylaxis, myocarditis, and thrombosis with thrombocytopenia syndrome (TTS), which is characterized by blood clots and low platelet levels. Medical experts emphasize the need for careful monitoring and further research to confirm these events.

The report identified several types of AESIs, including skin and subcutaneous disorders, nervous system disorders, and common conditions among adolescents such as musculoskeletal disorders, menstrual abnormalities, and hypothyroidism. Serious AESIs were rare but included stroke and Guillain-Barre syndrome, affecting 0.3% and 0.1% of participants, respectively.

The study also indicated that women and adolescents with a pre-vaccination history of COVID-19, comorbidities, or post-vaccination typhoid had significantly higher odds of experiencing persistent AESIs, with increases of 1.6, 2, 2.7, and 3.2 times, respectively.

Need for Extended Surveillance

Researchers advocate for extended surveillance of vaccinated individuals to better understand the progression and outcomes of late-onset AESIs. "Focused monitoring for persistent AESIs is warranted for individuals with a pre-vaccination history of COVID-19," the study noted. It also highlighted that adults with comorbidities, such as hypertension, are at higher risk of AESIs and persistent AESIs following BBV152 (Covaxin) administration.

What is Covaxin?

Covaxin, developed by Bharat Biotech, is also known as BBV152. It is an inactivated vaccine that uses a modified or dead version of the SARS-CoV-2 virus, which cannot replicate and therefore cannot cause disease. The vaccine is administered in two doses and has an efficacy rate of 78%, according to clinical data. India's Central Drugs Standard Control Organization authorized Covaxin for emergency use on January 3, 2021.