Deadlier strain of mpox spreads to more countries

Cases of a deadlier strain of mpox have been confirmed in four countries in Africa, raising alarm among health officials around the world.

Levels of mpox, formerly known as monkeypox, in the Democratic Republic of Congo have reached more than 14,000 reported cases and 511 deaths, and it has spread to four neighboring countries that had not previously reported cases, according to the World Health Organization- Burundi, Kenya, Rwanda and Uganda. WHO officials said on Wednesday that they plan to convene an emergency committee soon to determine whether the outbreak is a public health emergency of international concern.

The US Centers for Disease Control and Prevention also issued a health advisory on Wednesday to address the “risk of additional spread,” recommending that physicians maintain a “heightened index of suspicion for mpox” in people who recently traveled from the DRC or bordering countries.

Mpox is a viral disease that can spread easily among people and from infected animals. It can spread through close contact such as touching, kissing or sex, as well as through contaminated materials like sheets, clothing and needles, according to WHO. Symptoms include a fever, a painful rash, headache, muscle and back pain, low energy and enlarged lymph nodes. Mpox is characterized by two genetic clades, I and II. A clade is a broad grouping of viruses that has evolved over decades and is a genetic and clinically distinct group.

Clade Ib, which has been circulating in the DRC for years, causes more severe disease and is responsible for the current outbreak there. Although it is deadlier, there is no evidence to suggest that it is more transmissible, according to Dr. Rosamund Lewis, the WHO technical lead for the global mpox response.

Since January 2023, the DRC has reported the largest number of suspected clade I mpox cases on record: more than 22,000, with over 1,200 deaths. The number of cases reported in the first six months of this year matches that reported for all of last year, WHO Director-General Dr. Tedros Adhanom Ghebreyesus said at a news conference Wednesday, July 7.

For decades, the disease had largely been found in Central and West Africa, but it also began spreading in Europe and North America in 2022. No cases of clade I mpox have been reported outside central and eastern Africa, and the CDC classifies the risk that it will be brought into the US as “very low.” However, the agency continues to recommend mpox vaccination for people who are exposed to or at high risk of catching the virus.

The WHO has begun the Emergency Use Listing process for both approved mpox vaccines, aiming to expedite access for lower-income countries that have not granted their own approval.

The CDC advises anyone who has traveled to the DRC or its neighboring countries in the past 21 days and who has developed an unexplained rash to seek medical care immediately and avoid contact with others.