Two more people have tested positive for what is presumed to be monkeypox in New York City, city health officials said Wednesday.

“Two more people have tested positive for orthopoxvirus in NYC, which is presumed to be monkeypox. We will be conducting contact tracing and monitoring and will refer people for care if necessary. Monkeypox is rare in New York City but we can prevent the spread,” the city Department of Health and Mental Hygiene tweeted.

As of Tuesday night, the CDC said there were 18 confirmed cases nationwide from the recent outbreak. That’s double from the agency’s update last Thursday. Globally, the World Health Organization has identified infections from the current outbreak in 12 countries.

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