Tuberculosis is an illness very similar in effect to Covid19, the Wuhan – China virus
This is coming up on a vaccine that is 100 years old. Timely.
It’s not fool proof and will probably be only a part of the over all approach
Explainer: How an old tuberculosis vaccine might help fight the new coronavirus
By Lisa Rapaport
(Reuters) – There is no vaccine against the novel coronavirus, called SARS-CoV-2, that is spreading rapidly around the world. But scientists in several countries are testing a century-old tuberculosis (TB) vaccine to see if it might boost the immune system to reduce respiratory symptoms in people who get new coronavirus infections.
Researchers in Australia and Europe are testing whether the Bacille Calmette-Guerin (BCG) vaccine, introduced in the 1920s to fight tuberculosis, might be deployed to combat COVID-19, the respiratory disease caused by the novel coronavirus. Clinical trials are focused on two groups at high-risk for COVID-19: health care workers and the elderly.
Here is what scientists know, and what they are trying to find out:
HOW CAN A TB VACCINE HELP WITH OTHER INFECTIONS?
The BCG vaccine contains a live but weakened strain of tuberculosis bacteria that provokes the body to develop antibodies to attack TB bacteria. This is called an adaptive immune response, because the body develops a defense against a specific disease-causing microorganism, or pathogen, after encountering it. Most vaccines create an adaptive immune response to a single pathogen.
Unlike other vaccines, the BCG vaccine may also boost the innate immune system, first-line defenses that keep a variety of pathogens from entering the body or from establishing an infection. One study in Guinea-Bissau found 50% lower mortality rates in children vaccinated with BCG than in kids who did not get this vaccine. That is a much bigger drop in deaths than could be explained by a reduction in TB cases. Some studies have found similar reductions in respiratory infections among teens and the elderly.
WHAT SCIENTISTS DO NOT KNOW
Scientists do not have data yet on the effect of BCG vaccination on coronaviruses in general or SARS-CoV-2 in particular.
There are also many BCG vaccines, with different capacities to protect against various TB strains. Scientists need to determine which BCG vaccines might have the best ability to boost the innate immune system to fight COVID-19.
WHO SHOULD GET THE BCG VACCINE RIGHT NOW?
Scientists say it will take several months to get results from trials testing the BCG vaccine to fight COVID-19. In the meantime, people should not rush to get it because it has not been widely tested in adults and might be harmful. Also, a run on the BCG vaccine to fight COVID-19 might cause shortages for children who need it to prevent TB.
(Reporting by Lisa Rapaport; editing by Christine Soares, Nancy Lapid and David Gregorio)
Nations with Mandatory TB Vaccines Show Fewer Coronavirus Deaths
New study finds a correlation, but clinical trials are still in progress
The preliminary study posted on medRxiv, a site for unpublished medical research, finds a correlation between countries that require citizens to get the bacillus Calmette-Guerin (BCG) vaccine and those showing fewer number of confirmed cases and deaths from Covid-19. Though only a correlation, clinicians in at least six countries are running trials that involve giving frontline health workers and elderly people the BCG vaccine to see whether it can indeed provide some level of protection against the new coronavirus.
, assistant professor at the New York Institute of Technology and lead author of the study, started working on the analysis after noticing the low number of cases in Japan. The country had reported some of the earliest confirmed cases of coronavirus outside of China and it hadn’t instituted lockdown measures like so many other countries have done.
Otazu said he knew about studies showing the BCG vaccine provided protection against not just tuberculosis bacteria but also other types of contagions. So his team put together the data on what countries had universal BCG vaccine policies and when they were put in place. They then compared the number of confirmed cases and deaths from Covid-19 to find a strong correlation.
Among high-income countries showing large number of Covid-19 cases, the U.S. and Italy recommend BCG vaccines but only for people who might be at risk, whereas Germany, Spain, France and the U.K. used to have BCG vaccine policies but ended them years to decades ago. China
, where the pandemic began, has a BCG vaccine policy but it wasn’t adhered to very well before 1976, Otazu said. Countries including Japan
and South Korea, which have managed to control the disease, have universal BCG vaccine policies. Data on confirmed cases from low-income countries was considered not reliable enough to make a strong judgment.
With nearly 900,000 cases and 45,000 deaths, the world is struggling to control Covid-19. Any vaccine for the disease is more than a year away from being available and the effectiveness of drugs under trial won’t be known for months to come. That’s why it’s reasonable to look at whether BCG vaccine could provide protection against Covid-19, said Eleanor Fish, professor at the University of Toronto’s immunology department. Otazu’s study is yet to undergo review by peers, a strict criteria for science studies.
“I would read the results of the study with incredible caution,” Fish said.
Otazu, who said he’s already received comments from other experts, is working on a second version of his study that will address some of their concerns. He has also submitted the study for a formal review process with the journal Frontiers in Public Health.
One of the first to conduct the trial of BCG vaccine’s effectiveness against coronavirus is Mihai Netea, an infectious-disease expert at Radboud Universty Medical Center in the Netherlands. Netea’s team has already enrolled 400 health workers in the trial—200 got the BCG vaccine and 200 received a placebo. He doesn’t expect to see any results for at least two months. He’s also about to start a separate trial to study the effectiveness of the BCG vaccine on those older than 60. Other trials are taking place in Australia, Denmark, Germany, the U.K. and the U.S.