More than 200 people are being tracked in 27 US states due to the possibility of a rare infection with the monkeypox virus, US health officials said.
Officials fear these people may have come into contact with a Texas man who brought the disease from Nigeria earlier this month.
The man, believed to be the first case of monkeypox in the United States since 2003, was hospitalized but is in stable condition.
So far, no infection with the virus has been recorded or new cases found.
The Centers for Disease Control and Prevention says it is concerned that passengers on two flights the man took may have been exposed to the disease.
She added that the patient traveled to Atlanta, Georgia, from Lagos, Nigeria, on July 9, before boarding a flight to Dallas, where he developed the disease and was hospitalized.
It said it was working with airlines to assess “the potential risks to those who may have been in close contact with the traveler”.
She explained that the chances of the disease spreading on the plane were low because all passengers are obliged to wear masks in accordance with the safety procedures of the Covid-19 virus.
A CDC spokesperson told the BBC that they were “working with state and local health departments to monitor individuals who may have been exposed to monkeypox”.
“The risk to the general public is believed to be low,” the spokesperson added, stressing that he did not believe any of the 200 people they were monitoring posed a “high risk”.
Monkeypox is a rare viral disease in the same family as smallpox, but is much less severe.
The disease spreads in remote parts of Central and West African countries, near tropical rainforests.
Symptoms of monkeypox
- Initially fever, headache, swelling, backache, muscle aches, and general lethargy.
- Once the fever is gone, a rash can develop, often starting on the face and then spreading to other parts of the body, most often on the palms of the hands and the soles of the feet.
- The rash, which can be very itchy, changes and goes through various stages before eventually forming a crust that later falls off, and can cause scarring.
Most cases of the virus are mild, sometimes similar to chickenpox, and go away on their own within a few weeks.
Monkeypox can sometimes be more severe, with 1 in 100 cases fatal, according to the Centers for Disease Control.
Although rare, the disease has been discovered in the United States before, and in 2003 caused 47 confirmed or probable infections, and was linked to mice that were transferred to the country.