The study also claimed the BCG vaccine could be a ‘game-changer’ in the fight against coronavirus
Researchers in the US claimed to have established a link between the Bacillus Calmette-Guerin (BCG) vaccine, administered to millions of Indian children soon after birth to fight tuberculosis (TB), with lower cases of Covid-19 infection.
According to a report published by The Economic Times on Thursday, the yet to be published study from the New York Institute of Technology (NYIT) states that the harshness of coronavirus impact may be linked to national policies on BCG childhood vaccination, while citing the examples of Italy and the US.
The study also claimed that the BCG vaccine could be a "game-changer" in the fight against the deadly coronavirus.
"We found that countries without universal policies of BCG vaccination, such as Italy, the Netherlands, and the United States, have been more severely affected compared to countries with universal and long-standing BCG policies," the report quoted Gonzalo Otazu, assistant professor of biomedical sciences at NYIT, who leads the research team.
The team compared BCG vaccination policies of various nations with their Covid-19 morbidity and mortality and found a "significant positive correlation" between the year when universal BCG vaccination policies were adopted and the country's mortality rate, the report said.
According to the study, a combination of reduced morbidity and mortality could make the BCG vaccination a game-changer in the fight against Covid-19.
As one of the most widely used vaccines in the world, the BCG vaccine has existed for nearly a century and has been shown to be an effective tool in preventing meningitis and disseminated TB in children, the US researchers said in the report.
The inoculation is also believed to offer broad-ranging protection against respiratory infections, which present similar symptoms to Covid-19, they said.
The study comes at a time when the US reported almost 190,000 cases with more than 4,000 deaths, Italy with 105,000 cases and over 12,000 fatalities, and the Netherlands reported more than 12,000 cases of the disease and over 1,000 deaths.
However, Indian experts in the report said they were hopeful and encouraged but it was too early to say anything.
With the world's highest TB burden, India introduced its BCG mass immunization program in 1948.
As part of the program, the BCG vaccine is administered to millions of children at birth or soon after it, the report added.
The vaccine is the live weakened form of mycobacterium bovis -- the causative agent of tuberculosis in cattle -- related to mycobacterium tuberculosis, the bacteria which causes tuberculosis in humans.
"Every small thing gives us a ray of hope. It will be premature to say anything now. But the silver lining is that the BCG vaccine has proved quite effective against the SARS infection also," Lovely Professional University (LPU)’s Senior Dean for Applied Medical Sciences Monica Gulati said in the report.
"It was effective not in the sense that it was able to cure, but it was able to reduce the intensity," she added.
Saying that SARS virus was also basically a "coronated virus," Gulati further explained: "So since the current pandemic is less intense in the countries with BCG vaccine intervention and that it was effective.”
The report also quoted Rakesh Mishra, director of the CSIR-Centre for Cellular and Molecular Biology (CCMB) in Hyderabad, as saying that the NYIT findings were interesting but more scientific details were needed.
"We have come across the study, but we don't have a lot of scientific details about it. At the same time, it is interesting, but this is not something we can depend on while making policies or approaches against COVID-19," Mishra added.
The report also mentioned that the study also highlighted Australian researchers announcing plans to fast track large-scale testing to see if the BCG vaccination can protect health workers from the coronavirus.
As TB cases fell in the late 20th century, several higher-income countries in Europe dropped their universal BCG policies between 1963 and 2010.
The researchers noted that among the 180 countries with BCG data available today, 157 countries currently recommend universal BCG vaccination, the report said.
The remaining 23 countries have either stopped BCG vaccination due to a reduction in TB incidence or have traditionally favoured selective vaccination of "at-risk" groups, they added.