Second person tests positive for monkeypox in United States

A second person in the United States tested positive for monkeypox Friday, days after the country’s first case was identified in Massachusetts, officials said.

Health officials in New York said the person tested positive for the rare but potentially serious virus typically seen in central and western Africa.

The case has not yet been confirmed by the Centers for Disease Control and Prevention, but the person believed to have contracted the virus is isolating after showing symptoms consistent with the disease, the state’s health department said.

The department did not say how the person, from New York City, may have caught the virus, which has recently been reported in Europe, Australia and North America.

A disease expert at the University of California Los Angeles called the outbreak the “the most important” in the “history of monkeypox in the Western Hemisphere.”

A second suspected case in New York City was ruled out, the department said.

In a statement, the state health commissioner said the risk to the public was low, but she alerted health care providers to the case “so that they can consider this unusual diagnosis if their patients present with symptoms.”

The illness typically begins with flu-like symptoms that progress into a rash. The version of the virus that appears in central Africa is the most lethal, with a fatality rate of 10%.

One percent of the people who contract the West African virus die.

Monkeypox can be spread by animals and through person-to-person contact.

Disease experts are trying to determine how the virus is spreading and the origin of the current outbreak.

This story first appeared on NBCNews.com.