For the time being, said Rao, the general public doesn’t need to be particularly worried. Only weeks into this outbreak, it’s too early to tell what exactly is going on, and whether this outbreak has epidemic potential. “The worldwide concern from public health authorities is trying to understand how these are related to each other and what the causes are,” said Agam Rao, an infectious disease specialist and poxvirus expert at the CDC. With so many monkeypox cases concurrently popping up in different countries, public health officials’ immediate questions are whether the cases are related, and whether monkeypox is spreading in other communities undetected. (These numbers are changing rapidly a University of Oxford epidemiologist tweeted a link to a makeshift tracker where you can see the latest figures.) US authorities are investigating four additional suspected cases, two in Utah and one each in New York and Florida. Since early May, more than 250 cases have been detected in Europe and North America: 100 in Spain, 37 in Portugal, 56 in England, and 23 in Canada, as of May 23. What’s different - and concerning - about this Massachusetts case is that it’s occurring as clusters of monkeypox infections are popping up in other countries where the virus is also rare. Occasionally, public health authorities identify single cases in people recently returned from West or Central Africa, where the disease is more common. It wasn’t the first time the US had seen a case of monkeypox, a virus related to smallpox that causes flu-like symptoms and a rash, and can sometimes be deadly. On Wednesday, May 18, the CDC confirmed a case of monkeypox in a Massachusetts man who had recently traveled to Canada.