US officials have confirmed a case of monkeypox in a Massachusetts resident who had recently traveled to Canada, where health officials are investigating 17 cases in the Montreal area.

This is the first monkeypox case detected this year in the United States. In 2021, both Maryland and Texas reported single cases in residents who had recently traveled to Nigeria, where the virus is endemic.

But the current case and more than two dozen cases in Europe do not involve recent travel to endemic countries. Instead, community spread is suspected among men who have sex with men, suggesting close sexual and personal contact is behind the recent uptick in cases.

"Many of these global reports of monkeypox cases are occurring within sexual networks. However, healthcare providers should be alert to any rash that has features typical of monkeypox," said Inger Damon, MD, PhD, a poxvirus expert at the Centers for Disease Control and Prevention (CDC) in a press release. "We're asking the public to contact their healthcare provider if they have a new rash and are concerned about monkeypox."

According to the CDC, monkeypox is being spread through contact with body fluids, monkeypox sores, or shared items (such as clothing and bedding) that have been contaminated with fluids or sores of a person with monkeypox.