To date, more than 130 million doses of Covaxin have been administered in India.
Covaxin, one of the main vaccines used during coronavirus vaccination in India, offers only 50% protection against symptomatic COVID-19, according to a field study that This vaccine is less effective than originally thought.
As India was hit by its second major Covid wave earlier this year, researchers at the All India Institute of Health Sciences in Delhi analyzed data from 2,714 hospital medical staff who showed signs of infection. infection and underwent RT-PCR testing between April 15 and May 15, according to a study published in the Lancet Infectious Diseases journal. At the start of the country’s vaccination campaign in January, staff at AIIMS were exclusively provided with Covaxin, an injectable drug run by India’s state-funded health research agency and a local company. Bharat Biotech International Ltd.
The authors found that two weeks or more after completing the two-dose regimen, the adjusted efficacy of the vaccine against symptomatic Covid was 77.8% lower for which interim results were established in end-stage trials, one that was published in The Lancet earlier this month. High rates of infection and exposure to the virus among hospital staff, the researchers say, may have contributed to Covaxin’s weaker real-world effectiveness, along with its ability to mutate. delta recently appeared to have rendered the shot less protective, the researchers said.
“Our study provides a more complete picture of how BBV152 behaves in the field and should be considered in light of the conditions of the Covid-19 spike in India, combined with the potential for immune evasion. possible epidemic of delta variation,” Manish Soneja, an adjunct professor of medicine at AIIMS in New Delhi, said in a statement referring to the vaccine’s scientific name.
While various studies indicate that almost all Covid vaccines are less effective against the highly infectious delta variant, which started spreading across India in early 2021, new research About Covaxin could reduce the appeal of vaccination at a time when Bharat Biotech is scaling up production and as India restarts vaccine shipments abroad.
To date, more than 130 million doses of Covaxin have been administered in India. Bharat Biotech and the government, which has widely promoted the vaccination, sought to shut down controversy over early licensing of the vaccine in January before it completed phase 3 human trials. , which made many in the country hesitant at the time.
The World Health Organization’s independent technical committee also took months before granting emergency approval for Covaxin in early November, repeatedly asking Bharat Biotech for more data. Krishna Ella, president of the Hyderabad-based vaccine maker, said the WHO had given it the green light for so long because of the criticism surrounding the shot, which was developed using transmissible virus technology. system.
The AIIMs study did not estimate the vaccine’s effectiveness on hospital admissions, serious illness and death, the researchers said, while conceding that it was not designed to estimate protection over time intervals. different time. The patients were not tested to see if they were symptomatic due to a specific variant, and the authors also point out a lack of data on comorbidities and prior infections.
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