BCG vaccine stimulates immune system, may help COVID-19 patients

A new research says that the BCG vaccine, which protects elderly people from respiratory infections, may also possibly offer protection against COVID-19.

Since the beginning of the COVID-19 pandemic, scientists have been trying to see if any existing vaccines can offer protection against the virus that has caused chaos across the world. They have also look at drugs that can do the same. The malaria drug hydroxychloroquine is one example. However, experts have not been able to find any conclusive evidence that these medications can be of any help. Though many studies have already been undertaken and others are still going on, there is no conclusive evidence regarding this yet. Now, researchers from the Netherlands say that the BCG vaccine may help in the fight against the global health crisis.

The Bacille Calmette-Guerin or BCG vaccine, originally made against tuberculosis, gives an effective preventive action against various infections. It may also possibly offer protection against COVID-19 too, say researchers, adding that it also protects elderly people from respiratory infections. This vaccine is frequently given to children. Now a double-blind randomised clinical study from Radboud University in the Netherlands, published in the journal Cell, shows that elderly people also benefit from it. According to researchers, two years ago, they started the ACTIVATE study, with the aim of showing whether BCG vaccination could protect against infections in vulnerable elderly people.

BCG protects the elderly from infections

According to the researchers, patients over 65 years of age who were admitted to hospital were randomised to receive BCG or placebo vaccination at their discharge. All participants were followed for a year to see if BCG could protect them against a broad range of infections. The team revealed that the ACTIVATE study had already started before the corona pandemic. A total of 198 elderly people were given either a placebo or a BCG vaccine upon discharge from the hospital. During the research, there was a noticeable difference: in the placebo group, 42.3 per cent of the elderly developed an infection, while this was the case in only 25 per cent of the BCG group.

Protection against viral diseases

The BCG-vaccinated participants had their first infection on average 16 weeks after vaccination, compared to 11 weeks for the placebo group. There was no difference in side effects. The most important observation was that BCG could mainly protect against respiratory infections: BCG-vaccinated elderly people had 75 per cent fewer respiratory infections than the elderly who received placebo. Although most protection seems to have been against respiratory infections of (probably) viral origin, whether or not BCG also works against COVID-19 has not yet been demonstrated, due to the low prevalence of COVID-19 in this study, the team said.

Safe And effective

However, the study does show that it is safe to give the BCG vaccination to the elderly and that it can protect them against various infections. Several studies are underway that look specifically at the effects of BCG on COVID-19. Last month, a study published in the journal Cell Reports Medicine, revealed that the BCG vaccine has a general stimulating effect on the immune system and is, therefore, effective against COVID-19.

(With inputs from IANS)