The United States has just confirmed its first known case of the more severe clade I mpox strain, according to the CDC, a startling development in the ongoing battle against the viral disease.
The patient, who recently traveled from Eastern Africa, where an outbreak is raging, is now isolating at home after receiving treatment. The CDC emphasizes that the risk to the public remains low, but this news raises pressing questions.
Clade I mpox, known for causing more severe illness and a higher death rate than the clade II strain that sparked a major U.S. outbreak in 2022 and 2023, has been responsible for outbreaks in Africa. The CDC noted that “recent travel-associated clade I mpox cases outside of Africa have all been attributed to subclade Ib,” which has caused relatively mild illness thus far. However, the historical death rates for clade I, ranging from 3% to 11%, demand attention. While recent data suggest better clinical outcomes in countries with robust healthcare systems like the U.S., the sheer emergence of this strain here is **deeply concerning**.
Meanwhile, the WHO reports a surge in mpox cases across Africa, with hotspots in the Democratic Republic of Congo, Burundi, and Uganda. On November 22, the organization’s emergency committee will decide whether the outbreak still constitutes a global public health emergency.
For now, vigilance is key. The CDC recommends avoiding close contact with symptomatic individuals or contaminated materials and urges eligible people to receive two doses of the mpox vaccine.
