Could old vaccines for other germs protect against COVID-19?
WASHINGTON — 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. “This is still a hypothesis,” said Dr. Mihai Netea of Radboud University Medical Center in the Netherlands. But if it works, “it could be a very important tool to bridge this dangerous period until we have on the market a proper, specific vaccine.” The World Health Organization issued a stern warning Monday not to use the TB vaccine against COVD-19, unless