No Evidence BCG Vaccine Works Against Coronavirus – WHO

No Evidence BCG Vaccine Works Against Coronavirus – WHO

The World Health Organisation (WHO) says there is no evidence that Bacille Calmette-Guérin (BCG) vaccination results in fewer deaths from coronavirus for countries that use it.

The global health agency on its website said two clinical trials addressing this question are underway.

“There is no evidence that the Bacille Calmette-Guérin vaccine (BCG) protects people against infection with COVID-19 virus,” WHO said.

Scientists from Johns Hopkins Bloomberg School of Public Health found that the death rate is 5.8 times lower in countries that use the BGC vaccine.

According to the researchers, ongoing studies might suggest that there was a correlation between the death rates and the use of BCG vaccine.

“Although the research is still ongoing, statistical data from the ongoing COVID-19 outbreak has shown that death rates in countries where BCG have been administered as part of the immunisation routine are lower, when compared to countries where the vaccine is not used,” the researchers said.

However, WHO said it will evaluate the evidence when it is available.

“In the absence of evidence, WHO does not recommend BCG vaccination for the prevention of COVID-19,” it said

WHO continues to recommend neonatal BCG vaccination in countries or settings with a high incidence of tuberculosis.

“There is experimental evidence from both animal and human studies that the BCG vaccine has non-specific effects on the immune system. These effects have not been well characterised and their clinical relevance is unknown,” it said.

BCG vaccination prevents severe forms of tuberculosis in children.

Review

Meanwhile, WHO has updated its ongoing evidence review of the major scientific databases and clinical trial repositories, using English, French and Chinese search terms for COVID-19, coronavirus, SARS-CoV-2 and BCG.

It said ecological studies are prone to significant bias from many confounders, including differences in national demographics and disease burden, testing rates for COVID-19 virus infections, and the stage of the pandemic in each country.

It said the review also yielded two registered protocols for clinical trials, “both of which aim to study the effects of BCG vaccination given to healthcare workers directly involved in the care of patients with COVID-19.”