The cases include one death, WHO Director General Dr. Tedros Adhanom Ghebreyesus said during opening remarks at the meeting, provided to the media via news release.

The meeting, which is closed to media and the public, was convened to advise the director general on whether the global monkeypox outbreak constitutes a “public health emergency of international concern.” If the committee comes to that conclusion, it will offer temporary recommendations to prevent and reduce spread of the disease, and to manage the global public health response.

A decision will not likely be announced before Friday, WHO officials said.

“I imagine it (an emergency) will be declared,” Dr. Panagis Galiatsatos, an assistant professor at Johns Hopkins’ Division of Pulmonary & Critical Care Medicine and an ICU doctor, told Fortune on Thursday.

“We should have a reasonable concern for monkeypox—we don’t know its long-term complications,” added Galiatsatos, who treats Long COVID patients.

While it should be easier to stop the spread of monkeypox than of COVID, given that the poxvirus is thought to be predominately transmitted via skin-to-skin contact, monkeypox has a long incubation period. Patients can take weeks to become symptomatic, making contact tracing more difficult, he said.

WHO emergency committees only currently exist for COVID-19 and polio. Seven additional past emergency committees have previously been convened for diseases including Ebola, H1N1, and MERS.

As of Wednesday, 156 confirmed cases had been reported from nearly half of the states in the U.S., according to CDC data.

The fact that an emergency committee was convened “tells you that the director is worried,” Dr. Georges Benjamin, executive director of the American Public Health Association, told Fortune last week.

The WHO has often been accused of reacting too slowly, Benjamin said, adding of Adhanom Ghebreyesus, “I think he’s trying to get his hands around this.”

“When you see something this different, you want to know what you’re missing,” Benjamin said. “You want to lay out a strategy to understand what you don’t know, evaluate what you do know.”

Such a meeting would let health officials from around the globe set an agenda for research and treatment of patients, he said.

“Hopefully we think about how we coordinate this across the world, because it’s clearly a worldwide outbreak.”

As the virus continues to move beyond Africa, where it’s endemic, via an atypical pattern, scientists are rushing to figure out just how it’s spreading.

Monkeypox is usually found in rural African areas where people have close contact with infected rats and squirrels. It is typically transmitted from human to human through close contact, which may include sex and could include contact with personal items like sheets and clothing. Airborne transmission is known to be possible but has yet to be confirmed.

Human-to-human transmission of the smallpox-related virus can occur via “respiratory droplets (and possibly short-range aerosols),” the WHO wrote in a June 4 situation update, in which it cautioned against large gatherings, which may promote transmission.

Earlier this month, the CDC raised its alert level for potential monkeypox transmission among travelers, advising them, among other things, to wear a mask while traveling. On Tuesday, the masking advice disappeared from its website. When asked why, the CDC told Fortune it had removed the phrase “because it caused confusion.” The agency did not respond to a request for further elaboration, nor did it respond when asked if there was concern about airborne transmission.

Most cases reported over the past six weeks have been among men who have sex with men. But other populations could have ongoing outbreaks that have gone undetected, experts caution.

The LGBTQ community tends to access health screenings frequently, which may mean its members are diagnosed more often. But it doesn’t mean that other populations aren’t carrying the disease at equal, or greater, levels, Galiatsatos said.

“This is not a gay-related disease,” he said, adding that heterosexual men can transmit monkeypox to women just as easily, but they may not seek health care as frequently.