The United States reported its first case of the more aggressive strain of mpox on Saturday. This case involves a California resident who recently traveled from East Africa.
This case was confirmed by the California Department of Public Health and reported to the Centers for Disease Control and Prevention.
The person was treated in San Mateo County based on his travel history and symptoms, and is now isolated and recovering at home, according to a press release from the state Department of Health. The statement said public health workers are contacting people who had close contact with the patient, but there is “no current concern or evidence” that the virus is spreading in California or the United States.
The U.S. is the sixth country outside Africa where the strain of the virus has been detected, and it can cause more severe illness than the version of the virus that became widespread in 2022, according to the CDC.
The World Health Organization declared a global public health emergency in August, the second time in two years for mpx, as the strain spread to several African countries.
Mpox, formerly known as monkeypox, is a viral infection that causes painful lesions, often with flu-like symptoms. It is divided into two distinct groups: Clade I, which are more aggressive strains, and Clade II, which are somewhat milder strains.
Clade II was behind the 2022 pandemic, resulting in at least 32,000 infections and 58 deaths in the United States
Until recently, clade I had not spread beyond Central and East Africa, where it is considered endemic. However, due to the outbreak in the Democratic Republic of the Congo, cases have also occurred in eight other African countries this year. In August, the first case of the virus outside Africa was confirmed in Sweden. A few days later, an infected person was confirmed in Thailand. Both patients had spent time in Africa.
Travel-related cases have also been confirmed in Germany, India and the United Kingdom, according to the CDC.
Mpox is spread by direct contact with infected people, animals, or contaminated items such as clothing or bedding. The Clade II version that spread in 2022 was primarily transmitted through sexual contact, especially among men who have sex with men.
According to disease experts, in the current outbreak, clade I is mainly spread through contact with infected animals and transmission within households. According to the Centers for Disease Control and Prevention, two-thirds of suspected cases between January 2023 and April 2024 involved children under 15. But one strain, clade type Ib, also spread through sexual contact among female sex workers and men who have sex with men in the Congo.
It is unclear how transmission will occur in the United States, but some experts predict that clade I could spread among the same sexual networks by 2022.
“We expect to see cases confirmed, and we think it’s likely to be transmitted to the same populations that were at higher risk,” said Dr. Mark Siegel, associate professor of medicine at George Washington School of Medicine and Health Sciences. Ta. In the 2022-2023 epidemic. I think this poses little risk to the general public. ”
Previous clade I mpox outbreaks in Africa have killed up to 10% of those who became ill, whereas the current outbreak in the Democratic Republic of Congo has a case fatality rate of approximately 5%. This compares to a global case fatality rate of 0.2% for the 2022 outbreak.
But health officials have reason to believe that clade I may pose a lesser threat in the United States this year than in African countries, given lower malnutrition rates and stronger health systems. said.
The United States is also more prepared for an outbreak than in 2022. The CDC has ordered doctors to test for mpox, and wastewater treatment plants across the country, including some airports, are testing for both clades.
Additionally, the country has a sufficient supply of the two-dose Ginneos vaccine, which is available to men who have sex with men and other high-risk groups. The Department of Health and Human Services says two doses of the vaccine or previous infection can protect against severe clade I disease.
The United States administered approximately 1.2 million vaccine doses between May 2022 and January 2023. Health officials hope to expand coverage as only 23% of the population at significant risk has been fully vaccinated.
Mpox usually begins as a rash, followed by small bumps on the skin, followed by fluid-filled blisters that eventually turn into scabs. You may also experience fever, headache, muscle aches, back pain, low energy, and swollen lymph nodes.
Some people infected with clade II in the United States have described the lesions as extremely painful. Historically, it has appeared on the face, chest, palms, and soles of the feet, but during the 2022 outbreak, lesions appeared around the genitals and anus, or inside the mouth and throat.
