BCG vaccine does protect against severe coronavirus, study finds

by Assistant Professor Luis Escobar of the College of Natural Resources and Environment and two colleagues at the National Institutes of Health found that in places with a 10 per cent greater prevalence of the BCG vaccine there was also a 10.4 per cent reduction in Covid-19 deaths.

This was after the researchers had taken differences in social, economic and demographics into account.

Writing in their paper, they say: “This epidemiological study assessed the global linkage between BCG vaccination and COVID-19 mortality. 

“Signals of BCG vaccination effect on COVID-19 mortality are influenced by social, economic, and demographic differences between countries. 

“After mitigating multiple confounding factors, several significant associations between BCG vaccination and reduced COVID-19 deaths were observed.”

Escobar, a faculty member in the Department of Fish and Wildlife conservation and an affiliate of the Global Change Centre said: “In our initial research, we found that countries with high rates of BCG vaccinations had lower rates of mortality.

"But all countries are different: Guatemala has a younger population than, say, Italy, so we had to make adjustments to the data to accommodate those differences.

“The purpose of using the BCG vaccine to protect from severe COVID-19 would be to stimulate a broad, innate, rapid-response immunity.”

Escobar stresses that the team’s findings are preliminary and that further research is needed to support their results to determine what the next steps should be for the researchers. 

The World Health Organization noted that there is no current evidence that the BCG vaccine can protect people from COVID-19 infections.

They also stated that it does not currently recommend BCG vaccinations for the prevention of COVID-19.

'CLINICAL TRIALS UNDERWAY'

There are currently clinical trials underway to establish whether BCG vaccination in adults confers protection from severe COVID-19.

"We're not looking to advise policy with this paper," Escobar said.

"This is, instead, a call for more research.

"We need to see if we can replicate this in experiments and, potentially, in clinical trials.

"We also need to come back to the data as we get more information, so we can reevaluate our understanding of the coronavirus pandemic."

Peter Openshaw, a professor of experimental medicine at Imperial College London, believes the vaccine could work as it seems to trigger something known as "trained immunity" - where the whole immune system is on alert.

He told : "The level of alertness remains high for weeks or months after having the vaccine.

"It means you may be less likely to catch infections during that period because the immune system is more likely to respond very quickly if it spots a foreign invader."