Vaccines continue to be a controversial topic. But you will be relieved to know that this article is not about modern COVID vaccines. Rather, it is about a vaccine that is 101 years old. A new study suggests that the very old BCG vaccine might help people avoid COVID-19. The Bacillus Calmette-Guerin or BCG vaccine was first tested in humans in 1921 in Paris to protect babies against tuberculosis. BCG is still being administered to infants in countries where TB is common.
Type 1 Diabetes, BCG and an Accidental COVID Study:
A study begun before the start of the pandemic has revealed some intriguing results in the fight against COVID (Cell Reports Medicine, Aug. 8, 2022). Investigators were testing whether patients with type 1 diabetes could be protected from a variety of pathogens. People with this kind of diabetes are especially vulnerable to infections. The theory was that BCG vaccination might activate the immune system broad-based manner.
Some volunteers received BCG injections while others got placebo shots.
Early in the pandemic the researchers tracked which participants came down with the coronavirus.
Only 1 of the 96 volunteers who had gotten active BCG injections was infected with COVID-19. That’s about 1 percent.
On the other hand, over 12 percent of those who received placebo injections caught COVID. That’s at least as good at the results for mRNA vaccines.
The authors conclude that:
“The BCG vaccine effectively protects against COVID-19 and provides broad infectious disease protection…Also the BCG vaccine is safe, effective, affordable, and potentially protective against every changing viral variant of the COVID-19 pandemic, based on its broad-based protection against other infections.”
Did you appreciate the importance of that last sentence? Here we are, over 2.5 years into this pandemic and people are still catching and dying from COVID-19. Even after 2 vaccinations and 2 boosters, people are still catching SARS-CoV-2. Dr. Fauci caught it. So did President Biden and, more recently, First Lady Jill Biden.
The authors of the new study state:
“BCG’s broad-based infection protection suggests that it may provide platform protection against new SARS-CoV-2 variants and other pathogens.”
Did you also note the words “safe, effective, affordable“? Unless you are totally opposed to all vaccines, that should come as good news.
The BCG Vaccine Has Existed for Over 100 Years!
After 101 years we should know a lot about this vaccine. No one can claim that it was rushed to the market. And the new study is not the first to report protection against COVID.
A study published in the Journal of Clinical Investigation (Nov. 19, 2020) also revealed that the BCG vaccine might protect against COVID-19.
The authors of this study point out that:
“Bacillus Calmette-Guérin (BCG) is a live-attenuated vaccine strain of Mycobacterium bovis used against tuberculosis, however various studies have demonstrated that the BCG vaccine also induces potent and non-specific protection against other non-related diseases. Early administration of the BCG vaccine reduces child mortality by ~38-45%, mainly as a result of decreased neonatal sepsis, respiratory infections, and fever. Non-specific effects of BCG vaccination are not limited to children, as BCG vaccination in adolescents leads to a 70% decrease in the incidence of respiratory tract infections, and BCG-vaccinated elderly people (age 60-75) also experience fewer respiratory infections.”
The FDA has also approved BCG as an immunotherapy to treat bladder cancer.
The BCG vaccine stimulates what is called the body’s innate immune system. This trained immunity leads to activated natural killer (NK) cells and macrophages. These are the body’s first line of defense against invading viruses and other organisms. You can learn more about this aspect of the immune system by listening to our podcast with a noted virologist and immunologist at this link.
Show 1233: How Does Your Immune System Overcome Viruses?
Understanding innate immunity can help us appreciate how can the immune system overcome viruses, including SARS-CoV-2.
The Results of the “Old” BCG Vaccine Study:
In that study, over 6,000 healthcare workers were tested for SARS-CoV-2 antibodies. They also provided information about prior vaccinations. People who had received a BCG vaccination were much less likely to have developed COVID-19.
Here is what the authors concluded:
“Overall, in our cohort of HCWs [health care workers], we observe a protective and non-specific association between history of BCG vaccination and reduced SARS-CoV-2 infection, seroprevalence, as well as presence of COVID-19-related symptoms. The reported observation that BCG vaccination might be effective against SARS-CoV-2 infection and could potentially be used preventively to prevent COVID-19 needs to be further confirmed by randomized placebo-controlled blinded clinical trials, which are currently underway.”
BCG Vaccine vs TB:
It is estimated that over 100 million kids get a BCG vaccine every year to prevent tuberculosis. Although TB is not common in many developed countries, it is a killer around the world.
An article published in EMBO Molecular Medicine back on May 8, 2020, describes the Japanese situation:
“Japan, like many other countries including China, Korea, India, and the Russian Federation, have mandatory childhood BCG vaccines against tuberculosis. These countries have so far a relatively low per capita death rate from COVID‐19 compared to countries that have no mandatory BCG vaccines (USA, Spain, France, Italy, The Netherlands)…This association between BCG vaccination and apparent low COVID‐19 incidence in Japan has spurred the idea that these two things may be linked.”
BCG Vaccine vs. COVID-19: A Canadian Perspective
An article published in the Canadian Journal of Public Health (Nov. 19, 2020) offers this overview of the BCG vaccine:
“Currently, there is a widespread discussion in the scientific community regarding BCG vaccination as an effective intervention to mitigate the COVID-19 pandemic. The objective of this short commentary is to briefly present the state of knowledge and perspectives regarding the potential of BCG studies and vaccination in the Canadian context.
“Since the beginning of the COVID-19 pandemic, randomized clinical trials have been launched to assess BCG protection, targeting health care workers mainly. A total of 19 phase 3 trials in 13 countries were registered in ClinicalTrials.gov as of September 30, 2020, and first results are expected in early 2021. One of these trials is conducted by the University Health Network in Toronto.”
Final Thoughts:
The BCG vaccine has a 100-year history. The FDA has approved this vaccine for treating bladder cancer. People who are traveling to countries with a high incidence of tuberculosis can also get a BCG shot. Now that randomized clinical trials demonstrate that this vaccine can help protect against COVID-19, we hope that manufacturing will gear up quickly. The cost should be quite affordable. Stay tuned for the latest research in our newsletter.
