Senior Biden administration officials said Friday that the United States is preparing for the possible arrival of a more severe version of mpox, which has taken off in the Democratic Republic of Congo and other countries in Africa resulting in more than 600 deaths there.
As of Thursday, there have been more than 24,800 reported cases of this version of the virus, known as clade 1, so far this year, the World Health Organization said at a separate briefing Friday. The WHO declared the outbreak a global health emergency in August.
Last month, Sweden confirmed a case of clade 1, the first known case outside of Africa, followed by a case in Thailand several days later. Both patients had spent time in Africa.
A different version of mpox, clade 2, triggered a global outbreak in 2022 and a surge of cases in the U.S. Clade 1 is more severe and can kill up to 10% of people infected, though recent death rates have been around 1% to 3.3%, according to the CDC.
On a call with reporters, senior administration officials said that as infections have risen in Africa, the U.S. has been gearing up for its own cases.
“We’ve been preparing for the arrival of clade 1 in the United States for many months now, especially as we saw the outbreak in DRC and neighboring countries accelerate,” one official said.
The government is expanding its mpox surveillance efforts, primarily through wastewater analysis, and is reaching out to the medical community to educate members on what to watch for, including the severity of clade 1 and how it spreads, according to officials.
Officials said they're also making sure testing is more widely available.
Any doctor in the U.S. can order an mpox test that can be run through a national laboratory. If positive, it can be tested for clade 2. If those results are negative for clade 2, the doctor can make a presumptive diagnosis of clade 1; that diagnosis will need to be officially confirmed by the Centers for Disease Control and Prevention, according to officials.
The Jynneos mpox vaccine, given in two doses, is effective against both clade 1 and clade 2 of mpox.
The CDC’s vaccine recommendation remains limited to anyone who is considered at high risk of catching the virus, mainly gay and bisexual men.
Most people with health insurance can get the vaccine at major pharmacy retail chains including CVS and Walgreens, the officials said. The vaccine is also available for free at public health departments and community health centers.
More vaccines are being held in the U.S. national stockpile, officials said, although they declined to say how many.
“There is a sufficient amount of vaccine for the U.S. population,” an official said.
The U.S. is also working with government scientists and drug companies to develop potential new treatments. There are currently no approved treatments for mpox. The Food and Drug Administration has approved an antiviral treatment known as TPOXX for smallpox, which is closely related to mpox, although a recent clinical trial found that the drug is not effective against clade 1.
