A case of monkeypox was confirmed in person in Maryland, the Centers for Disease Control and Prevention reported Wednesday.
It is the second case this year involving a person who traveled to the United States from Nigeria. The first case was in a Texas resident in July and does not relate to the Maryland case.
Prior to this year, the disease had not been seen in the United States since a 2003 epidemic that killed 47 people.
Symptoms of the virus include fatigue, fever, headache and muscle aches. Within a week to 14 days after exposure, patients develop a swollen rash that spreads throughout the body.
Most patients recover within a month, although they are considered contagious until the swollen tubercles have shrunk and fallen off. The disease is rarely fatal.
The CDC said the latter case coincides with an strain of the virus that has been circulating in Nigeria for several years. The patient is isolated, the agency said.
The CDC and other health officials are now working with the airline on which the patient was traveling from Nigeria to make contact with passengers.
The monkeypox virus spreads through respiratory droplets when an infected person sneezes or coughs. Because masks were required during the flight, the CDC said the risk of anyone else on the plane being infected is low.
However, the agency is asking doctors to take care of any unusual rashes on patients, especially if they have traveled from Nigeria.
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