Two doses of vaccine helps fight Covid better: CMC study

The study, yet to be peer-reviewed, is authored by medical specialists Peter John Victor, K Prasad Mathew, Hema Paul, Malathi Murugesan, and Joy J Mammen.

Published: 12th June 2021 05:21 AM  |   Last Updated: 12th June 2021 05:21 AM   |  A+A-

Vaccination drive underway for fisherfolk and their family members at Kasimedu in Chennai on Friday | Ashwin Prasath

Express News Service

CHENNAI:  Two doses of the Covid vaccine offer higher protection against infection, hospitalisation, requirement for oxygen treatment, and ICU admission, finds a study by the Christian Medical College, Vellore. The study, yet to be peer-reviewed, is authored by medical specialists Peter John Victor, K Prasad Mathew, Hema Paul, Malathi Murugesan, and Joy J Mammen.

The CMC, a 2,600-bed tertiary care hospital with 10,600 employees, vaccinated as many as 8,991 healthcare workers (84.8 per cent of the total workforce) between January 21 and April 30 this year while 1,609 workers were not vaccinated.

Among those vaccinated, 93.4 per cent received the Covishield vaccine of Oxford-AstraZeneca, manufactured by the Serum Institute of India, and the remaining got Covaxin, a killed virus vaccine by Bharat Biotech.

The results showed that of the 7,080 healthcare staff who took both doses, infection was prevented in as much as 65 per cent people, hospitalisation prevented in 77 per cent, the need for oxygen prevented in 92 per cent, and ICU admission prevented in 94 per cent people. 

‘We now have data on how vax works in high-risk group’

Among the 1,878 people who only took the first dose, 61 per cent did not get infected, 70 per cent did not require hospitalisation, 94 per cent did not require oxygen therapy, and 95 per cent did not require ICU care. Among the 1,609 people who did not take vaccine, 27 per cent got infected while four per cent required hospitalisation and one staff with comorbidities died.

The study, however, did not look into the various variants responsible for the second wave, it says. Dr. Joy J Mammen, Professor, Department of Transfusion Medicine, Associate Director, CMC, said that vaccination is important for protection.

“The vaccines reduce infection, severity and reduces the requirement of oxygen treatment and ICU admission,” Mammen said. Reflecting on the study, Dr. Subramanian Swaminathan, infectious diseases specialist, Gleneagles Global Health City, said this was the first time in India, there is a realworld data on how vaccine works in a high-risk population, working in a hospital.


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