CDC issues new guidance on monkeypox symptoms as U.S. cases balloon

The U.S. has reported 72 cases of monkeypox across 18 states in the last month, making it the country’s largest monkeypox outbreak ever.

That total has grown significantly since the beginning of June, when just 19 cases were confirmed.

The Centers for Disease Control and Prevention released new guidance Tuesday about how to identify monkeypox during this outbreak, based on the symptoms doctors have observed so far. Some recent infections have presented differently than past cases in Africa, where monkeypox is endemic in 11 countries.

Traditionally, people with monkeypox have developed a fever, swollen lymph nodes, headaches and muscle aches, followed by a rash that starts on their face or in their mouth then spreads to other parts of their body — particularly the hands and feet.

But in many recent U.S. cases, patients first experienced a rash in the mouth or around the genitals or anus. And instead of widespread rashes, some patients saw scattered or localized lesions in areas other than the face, hands or feet. In some cases, flu-like symptoms developed after the rash, but other people didn’t have those symptoms at all.