Top Doctors 2020

An Old Tuberculosis Vaccine Might Be the Key to Fighting Covid-19

Dr. Jeffrey D. Cirillo and scientists at Texas A&M are researching the century-old treatment.

By Timothy Malcolm September 4, 2020 Published in the Fall issue of Houstonia Magazine

Dr. Jeff Cirillo sits in front of his desk.

Dr. Jeff Cirillo hopes the BCG vaccine will help people fight off Covid.

WHEN THE WUHAN MUNICIPAL HEALTH COMMISSION FIRST ANNOUNCED a pneumonia outbreak on December 31, 2019, Dr. Jeffrey D. Cirillo, professor of microbial pathogenesis and immunology at the Texas A&M Health Center, figured it wouldn’t cause a global pandemic. But as Covid-19 swiftly spread across the world, he had to work quickly.

“It takes 10 to 15 years to create and really develop a vaccine, so how do you get something together that can deal with a pandemic in months?” says Cirillo. “That’s the place where we started looking around.”

A race against the clock began immediately, and in April his team at Texas A&M, plus scientists and doctors at the University of Texas MD Anderson Cancer Center, the Baylor College of Medicine, the Harvard School of Public Health, and Cedars-Sinai Medical Center in Los Angeles, found a needle in a haystack. The discovery? Evidence indicated that one of the most widely used vaccines in the world—BCG, which prevents people from contracting tuberculosis—might be employed to lessen the effects of Covid-19. It could potentially mean fewer hospitalizations and deaths.

BCG, formally Bacille Calmette-Guérin, is something of a miracle vaccine. First used to treat tuberculosis in 1921, it’s still the only vaccination available to ward off the disease, which killed indiscriminately for millennia, and has strong success rates even today—a 2014 BMJ study found that BCG reduces TB infections by 27 percent and decreases the disease’s progression by 71 percent. But the vaccine has also been found to essentially train the immune system, providing a longterm boost to the cells in your body that fight off diseases, and respiratory tract infections in particular, a discovery that has caused it to be employed treating numerous other ailments.

When Cirillo and his fellow researchers turned their focus to understanding Covid-9, they noticed that the disease inflames and damages cells in a way similar to tuberculosis and cancer. If cells were reacting the same to the coronavirus, they hypothesized, maybe they would have the same response to the BCG vaccine. They decided to find out.

“For more than 100 years this vaccine has been tested against other infections. It works against cancer; it works against allergies, asthma,” says Cirillo. “So we needed to test this against Covid-19.”

There were more promising indications in the data already available as well. The teams researched the mortality rates of developing countries with mandatory tuberculosis vaccinations, discovering that many of those nations had a relatively low rate of Covid-19 hospitalizations and deaths.

They took their findings to the federal Food and Drug Administration, which approved late-stage clinical trials for investigating BCG’s effect on Covid-19 earlier this year. Cirillo secured $2.5 million from Texas A&M Chancellor John Sharp to begin trials, now ongoing at both the College Station campus and the Texas A&M Health Science Center in the Texas Medical Center, as well as in major cities throughout the Lone Star State. Similar trials using slightly different strains of the vaccine are taking place in other parts of the world, including in Australia and the Netherlands.

Health care workers and first responders such as firefighters and police officers are the focus of these six-month-long trials, which started in May. Once they agree to be part of the study, each subject is given an introductory care assessment, and a vaccination, while those who also participate in a sub-study are given an MRI. From there, doctors conduct periodic assessments. (Doctors are also using the study to research BCG’s efficacy in reducing cognitive impairment, which has been demonstrated in some patients with Covid-19, since there are some indications it might help prevent Alzheimer’s, too.) Each trial subject will take a cognitive test at both the onset and the close of the process. As of July about 300 people in Houston had been vaccinated as part of the study, with new subjects administered every few weeks.

If scientists find a reduced Covid-19 mortality rate, intensive care admission rate, and virus infection rate among the cohort administered with BCG, there’s a likelihood that the FDA will sign off on policy makers and medical professionals developing a national tuberculosis vaccination program, with the initial focus on people who would be high-risk if they were to catch Covid and on health care workers and first responders.

Cirillo says the best-case scenario is that a program develops in the fall. Since rolling out a program in the American health care system is a weighty process, though, it’s more likely to expect vaccinations to begin early next year. If BCG works, of course. While the vaccine wouldn’t eradicate Covid-19 or prevent anyone from getting it, thanks to the sleepless work of scientists and doctors—many right here in the Houston area—it may at least save untold numbers of lives by helping to mitigate the impact of the disease.

“You kind of feel stupid, actually. It’s one of those things that we should’ve had earlier,” says Cirillo. “But all of the foundation with tuberculosis had a purpose in this pandemic, and I think that’s been critical.” 

Show Comments