As much as 90 percent of TB bacteria released from an infected person may be carried in tiny droplets, called aerosols, that are expelled when a person exhales deeply, the researchers estimated. The findings were presented on Tuesday at a scientific conference held online…

The finding helps explain why tightly packed indoor spaces, like prisons, often are breeding grounds for TB, as they are for Covid. And the research suggests that some of the methods used to limit coronavirus transmission — masks, open windows or doors, and being outdoors as much as possible — are important in curtailing TB.

“Those of us who are TB people look at Covid and say, ‘Wow, it’s just a sped up version of TB,’” said Dr. Robert Horsburgh, an epidemiologist at Boston University who was not involved in the work.