“Then you have to touch that part of your hair or clothing that has those droplets, which already have a significant reduction in viral particles,” Dr. Janowski said. “Then you have to touch that, and then touch whatever part of your face, to come into contact with it. When you go through the string of events that must occur, such an extended number of things have to happen just right. That makes it a very low risk.”

Should I worry about doing laundry and sorting clothes? Can I shake viral particles loose from my clothes and send them into the air?

The answer depends on whether you’re doing routine laundry or cleaning up after a sick person.

Routine laundry should not cause worry. Wash it as you normally would. While some types of viruses, like the norovirus, can be tough to clean, the new coronavirus, like the flu virus, is surrounded by a fatty membrane that is vulnerable to soap. Washing your clothes in regular laundry detergent, following the fabric instructions, followed by a stint in the dryer is more than enough to remove the virus — if it was even there in the first place.

“We do know that viruses can deposit on clothing (from droplets) and then be shaken loose into the air with movement, but you would need a lot of viruses for this to be a concern, far more than a typical person would encounter while going for a walk outdoors or going to a grocery store,” Dr. Marr said.

The exception is if you are in close contact with a sick person. The Centers for Disease Control and Prevention recommends that you wear gloves when cleaning up after someone who is sick, and take care not to shake laundry and bedding. Use the warmest water setting possible and dry completely. You can mix laundry from an ill person with the rest of the household load. But just leaving laundry to sit for a while also reduces risk, because the virus will dry out and decay. “We know these types of viruses tend to decay faster on fabric than on hard, solid surfaces like steel or plastic,” said Dr. Marr.

So how long can the virus remain viable on fabric and other surfaces?

Most of what we know about how long this novel coronavirus lives on surfaces comes from an important study published in The New England Journal of Medicine in March. The study found that the virus can survive, under ideal conditions, up to three days on hard metal surfaces and plastic and up to 24 hours on cardboard.

But the study did not look at fabric. Still, most virus experts believe that the cardboard research offers clues about how the virus probably behaves on fabric. The absorbent, natural fibers in the cardboard appeared to cause the virus to dry up more quickly than it does on hard surfaces. The fibers in fabric would be likely to produce a similar effect.

A 2005 study of the virus that causes SARS, another form of coronavirus, provides further reassurance. In that study, researchers tested increasingly large amounts of viral samples on paper and on a cotton gown. Depending on the concentration of the virus, it took five minutes, three hours or 24 hours for it to become inactive. “Even with a relatively high virus load in the droplet, rapid loss of infectivity was observed for paper and cotton material,” the researchers concluded.