Scientists are dusting off some decades-old vaccines against other germs to see if they could provide a little stopgap protection against COVID-19 until a more precise shot arrives.
It may sound odd: Vaccines are designed to target a specific disease. But vaccines made using live strains of bacteria or viruses seem to boost the immune system’s first line of defense, a more general way to guard against germs. And history books show that sometimes translates into at least some cross-protection against other, completely different bugs.
There’s no evidence yet that the approach would rev up the immune system enough to matter against the new coronavirus. But given that a brand-new vaccine is expected to take 12 to 18 months, some researchers say it’s time to put this approach to a faster test, starting with a tuberculosis vaccine.
At the U.S. National Institutes of Health, researchers are in early discussions about proposals to study the TB and polio vaccines as a possible COVID-19 defense… .
Scientists not involved in the effort to try these vaccines against COVID-19 say it’s worthwhile to test.
“The scientific rationale I think is quite logical,” said Nizet, the UC-San Diego immune specialist. “The unknown is whether coronaviruses are in the spectrum of things that are efficiently protected” by that first-line innate immunity.