The U.S. Centers for Disease Control and Prevention has clarified its guidance on wearing face masks to avoid monkeypox, which primarily spreads through direct bodily contact.
Last week the agency updated its travel advisory for monkeypox and advised the public to go from practicing the “usual” precautions to practicing “enhanced” precautions, including regular hand washing and wearing a face mask, to avoid catching monkeypox.
That guidance was removed on Monday because it "caused confusion," a CDC spokesperson said in a statement to Reuters.
On Thursday, the CDC issued a media statement about how monkeypox is spread, though it didn’t mention the changed mask guidance.
Monkeypox, unlike COVID-19 or measles, is does not linger in the air and “is not transmitted during short periods of shared airspace,” the statement said. The CDC said it hasn’t heard of anybody catching monkeypox while sitting on an airplane near somebody with monkeypox, even on a long international flight.
However, monkeypox can spread through "saliva or respiratory secretions" during face-to-face contact, though prior studies show this is uncommon, the CDC said.
People who already have monkeypox are advised to continue wearing a mask around others in their homes if close contact is likely, the CDC says. Health care workers and people who may have close contact with somebody with monkeypox are also advised to wear masks.
“There are important differences between airborne transmission and transmission via respiratory secretions,” the CDC said. “Airborne transmission occurs when small virus particles become suspended in the air and can stay there for periods of time. These particles can spread on air currents, or sometimes even infect people who enter a room after the infected person has left. In contrast, monkeypox may be found in droplets like saliva or respiratory secretions that drop out of the air quickly. Long range (e.g., airborne) transmission of monkeypox has not been reported.”
Monkeypox mostly spreads when people have direct contact with body fluids or sores of somebody with monkeypox, or from touching clothing or linens that have touched those fluids, the CDC said.
Many confirmed monkeypox cases around the world have occurred in men who’ve had sex with other men, health authorities have said. The CDC says it’s studying whether monkeypox can be spread by semen.
As of Thursday, the CDC reports 45 confirmed monkeypox cases in 15 states and the District of Columbia. Globally, more than 1,200 cases have been reported.