California health officials have confirmed the first US case of a more severe strain of mpox, also known as monkeypox, in a traveler from Eastern Africa, ABC News reports.
The Centers for Disease Control and Prevention (CDC) announced the case involves a virus strain called clade 1b, which has been linked to a growing outbreak in Africa. Despite this development, the CDC emphasized that the risk to the general public remains low.
Mpox, a viral disease that causes a rash and flu-like symptoms, came into global focus during a 2022 outbreak caused primarily by a less severe strain, clade 2b. That strain spread mainly through close sexual contact, but a widespread vaccination campaign helped curb the outbreak. Clade 1b, however, has been associated with more severe cases and a broader range of transmission methods, including household contact, and has been responsible for over 12,000 cases and 47 deaths in Africa this year.
The individual diagnosed with the clade 1b strain recently traveled from Eastern Africa and sought treatment upon returning to the US Health officials are currently working to identify and notify anyone who may have been exposed. According to the CDC, casual contact during travel is unlikely to lead to significant transmission.
This case prompted the CDC to issue a health advisory, urging healthcare providers to be vigilant about mpox symptoms and report suspected cases to public health authorities.
Mpox symptoms typically include a rash that may appear on the hands, feet, chest, face, or near the genitals. The rash is often accompanied by flu-like symptoms such as fever, fatigue, and muscle aches.
For those already vaccinated against the clade 2b strain, the CDC does not currently recommend booster shots. Vaccination efforts during the 2022 outbreak were instrumental in reducing the spread, but for now, no changes to vaccination guidance have been announced for high-risk individuals.
The emergence of clade 1b in the US underscores the need for continued vigilance, particularly as this strain has shown the potential to spread through routes other than close sexual contact, affecting household members and children. While parts of Africa continue to battle significant outbreaks, the CDC and health officials are closely monitoring the situation to prevent further spread.
