ICMR study reveals effectiveness of Covid vaccine in preventing deaths

A study by the Indian Council of Medical Research (ICMR) on Covid vaccine has revealed the jabs have proven effective in preventing deaths in frontline personnel, with the study on Tamil Nadu policemen who have been inoculated showing significant results.

ICMR said in a tweet Tuesday its "study reveals that COVID-19 vaccine is effective in preventing deaths among front line workers," showing 82 per cent effectiveness on state police personnel who had received single dose and 95 per cent on those administered with two.

The study was done by the state police department, ICMR-National Institute of Epidemiology and Christian Medical College, Vellore.

Of the 1,17,524 police personnel in Tamil Nadu, between February 1 and May 14, 2021, 32,792 received one dose, 67,673 received two doses while 17,059 did not receive any vaccine dose at all, it said.

Among the 31 deaths of police personnel between April 13 and May 14 this year "four had taken two doses of the vaccine, seven had taken one dose and the rest 20 were unvaccinated," it said.

"The incidence of COVID-19 deaths among the vaccinated with zero, one and two doses were 1.17, 0.21 and 0.06 per 1,000 police personnel, respectively."

"The vaccine effectiveness in preventing COVID-19 deaths with one and two doses was 82 per cent (95 per cent CI: 57 - 92 per cent) and 95 per cent respectively," it said.

The incidence of mortality among vaccinated and unvaccinated individuals was compared to calculate the relative risk of mortality associated with COVID-19 vaccination, along with 95 per cent confidence interval (CI), it added.

Further, it said a 'cohort' study conducted among healthcare workers from a tertiary care hospital in the state indicated a strong protective effect of two doses of vaccines against hospitalisation, the need for oxygen therapy and need for ICU care.

"The analysis, however, has certain limitations as potential confounders including age, comorbidities and previous exposure to COVID-19 infection could not be adjusted for, as the vaccination details were collected as aggregated numbers," it said.

Also the effectiveness could not be estimated separately for each vaccine.

"In conclusion, our analysis indicated COVID-19 vaccination, even with single dose, was effective in preventing deaths."

"It is necessary to increase coverage of COVID-19 vaccines, regardless of the type of vaccines, to reduce mortality in current as well as future waves of COVID-19 epidemic," it added.