Countries who make use of the century old tuberculosis Bacillus Calmette-Guérin (BCG) vaccine are experiencing lower death rates from the ongoing coronavirus pandemic, which has been plaguing the world since December, a new study has shown.
The scientists from Johns Hopkins Bloomberg School of Public Health found that the death rate is 5.8 times lower in countries that use the century-old vaccine.
According to the researchers, ongoing studies might suggest that there is 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.
Researchers are currently testing to determine the role BCG has played on COVID-19 death rates in countries where the vaccine is being administered.
BCG vaccine is primarily used against tuberculosis (TB). It is recommended that the first jab should be given to a healthy baby as close to the time of birth as possible, while in areas where TB is not common, only children at high risk are typically immunised.
The vaccine is thought to boost a person’s immune system to fend off infections.
The BCG vaccine was invented a century ago and gives immunity to tuberculosis (TB), a bacterial infection.
BCG also has some effectiveness against Buruli ulcer infection and other non-tuberculous mycobacteria infections. Additionally, it is sometimes used as part of the treatment of bladder cancer
“The Johns Hopkins Bloomberg School of Public Health experts pooled publicly available data for the analysis,” it said.
An estimate on case fatality rate was produced from the best available data on mortality for the top 50 countries reporting highest case events.
“In order to mitigate the bias centered around the differential epidemic time curves experienced by the different countries, we calculated days from the 100th COVID-19-positive case to align the countries on a more comparable time curve,” the researchers explained.
Also, an average death rate was found to vary significantly, according to a country’s economic classification.
The BCG jab, which used to go to every child aged between ten to 14, was cut back in 2005 but researchers hope it will turbo-charge the immune system so that it is in a heightened state of readiness and able to detect and destroy the virus before it wreaks havoc on the body.
BCG is currently given to around 130 million babies every year to protect them from TB.
The COVID-19 Research
COVID-19 mortality per one million for low-middle-income, upper-middle-income and high-income countries were 0.4, 0.65 and 5.5, respectively.
The researchers call the fact the wealthier nations have a higher death rate ‘counter-intuitive’.
Previous trials discovered people that receive the jab, which costs as little as £30, have improved immune systems and are able to protect themselves from infection.
For example, in a trial among Native Americans, BCG vaccination in childhood was able to offer protection against TB up to 60 years after vaccination.
The precise way this durable vaccine helps fend off other infections is relatively unknown but it may be by boosting the immune system’s innate mechanisms.
These so-called off-target effects include enhanced protection against respiratory diseases, and have been recognised by the World Health Organization (WHO).
As TB infection rates dropped, doctors abandoned mass vaccination and, in 2005, switched to targeting only the most at risk — such as babies with infected relatives.
Researchers hope it will turbo-charge the immune system so that it is in a heightened state of readiness and able to detect and destroy the virus before it wreaks havoc on the body.
The researchers adjusted for factors which can skew the findings, such as a nation’s wealth and the percentage of elderly people in its population.
They then looked at the mortality per one million residents of every country with sufficient data.
The findings were published online on archive site medRxiv and not in a journal as the research is yet to be peer-reviewed.
It said COVID-19 is known to be more dangerous to people over the age of 65, and this demographic is less populous in poorer nations.
The researchers said their results should be taken with caution as there are several issues that may distort the findings.
“Despite all these caveats, the inverse relationship between country economic status and COVID19-attributable mortality, and the strong ecological association with BCG vaccination are intriguing,” he said.
“The findings warrant deeper epidemiological scrutiny and prospective evaluation in individually randomized trials.”
Trials to assess the usefulness of the BCG vaccine in the fight against the coronavirus pandemic are already underway.
Researchers hope administering the vaccine and boosting ‘innate immunity’ can buy enough time for specialised treatments and vaccines to be developed.