The Centers for Disease Control and Prevention issued an alert Wednesday for doctors to watch for signs of a more severe strain of mpox that’s currently spreading widely in parts of Africa.
The agency’s alert came hours after the World Health Organization’s Director-General Dr. Tedros Adhanom Ghebreyesu tweeted that he will be convening a group of advisers to determine whether the mpox outbreak should be declared a public health emergency of international concern. The committee will meet as soon as possible, Tedros said.
Cases of the strain, called clade 1, haven’t been reported outside of central and eastern Africa at this time, the CDC said in its alert. However, due to the risk of additional spread, the agency is recommending clinicians in the U.S. consider mpox in patients who have recently been in the Democratic Republic of Congo or to any neighboring country (Angola, Burundi, Central Africa Republic, Republic of Congo, Rwanda, South Sudan, Uganda or Zambia) and have symptoms of mpox.
Mpox, previously called monkeypox, is a virus that causes fevers, headaches, muscle aches and painful boils on the skin. It’s spread from person to person through close, skin-to-skin contact. It can be deadly.
The latest mpox strain is different from the virus that circulated globally in 2022, which mainly affected men who have sex with men. Those cases have decreased significantly in the U.S.
The CDC said in the alert that outbreaks in some provinces in the Democratic Republic of Congo have been associated with sexual contact.
In other parts of the country, however, patients have gotten sick through contact with infected animals, household transmission or patient care, the CDC said, adding that a high proportion of cases have been reported in children younger than 15.
“Most reported cases in known endemic provinces continue to be among children under 15 years of age,” the World Health Organization wrote on its website on June 14. “Infants and children under five years of age are at highest risk of severe disease and death.”
Clade 1 is worrisome because of its severity. Nearly 4% of clade 1 mpox cases are deadly, compared with less than 1% of the 2022 subtype, called clade 2.
The available mpox vaccine, from drugmaker Jynneos, is effective for both clade 1 and clade 2 of mpox, according to the CDC.