COVAXIN found 50% effective against COVID-19 in first real-world study
COVAXIN, India's indigenous coronavirus vaccine, is 50% effective against symptomatic COVID-19, the first real-world study of its effectiveness suggests. The study has been published in The Lancet Infectious Diseases journal. COVAXIN is India's first indigenous vaccine against the coronavirus and is one of the six vaccines approved in the country. Here are more details on this.
Why does it matter?
The new study suggests the shot is much less effective than initially believed. The vaccine was found 77.8% effective in an efficacy analysis of Phase-3 trial published in The Lancet earlier this month. Now the fresh findings may affect drug maker Bharat Biotech's ambitious plans for manufacturing and exports. However, the real-world effectiveness of vaccines often differs from trial findings.
Study assessed 2,714 healthcare workers
The study assessed over 2,700 hospital workers at the All India Institute of Medical Sciences-Delhi. The participants were symptomatic and underwent RT-PCR testing between April 15 and May 15 this year. The study period notably coincided with the second wave of the pandemic in India when the Delta variant was dominant. The vaccine's effectiveness stayed stable over the seven-week follow-up period.
What led to lower vaccine effectiveness?
The factors that may have contributed to lower vaccine effectiveness include the fact the participants were healthcare workers who naturally have a higher risk of exposure to infection. Further, the study was carried out at the peak of the second wave when test positivity rates were generally high. The authors, however, acknowledged the study did not estimate effectiveness against hospitalization, severe disease, and death.
'A more complete picture of COVAXIN's performance'
"Our study offers a more complete picture of how COVAXIN vaccine performs in the field and should be considered in the context of COVID-19 surge conditions in India, combined with possible immune evasive potential of the Delta variant," Dr. Manish Soneja said. "Our findings add to the growing body of evidence that rapid vaccine rollout programs remain the most promising path to pandemic control."
13 crore doses of COVAXIN used in India
COVAXIN is an inactivated whole-virion vaccine. It has been developed by Bharat Biotech in collaboration with the Indian Council of Medical Research's (ICMR) National Institute of Virology (NIV). It is India's second-most prevalent coronavirus vaccine and was cleared here in January this year. So far, over 13 crore doses of COVAXIN have been administered to the eligible population across India.
COVAXIN got WHO nod after a long wait
COVAXIN had secured the crucial Emergency Use Listing (EUL) from the World Health Organization (WHO) earlier this month. The EUL came months after Bharat Biotech submitted a request as it was repeatedly delayed over insufficient trial data.
