Health officials said on Friday that there are two different types of monkeypox in the US. Many of the cases in the US were caused by the same strain as the cases in Europe, but some samples show a different strain, he said.
Monkeypox usually begins with a flu-like illness and swelling of the lymph nodes, followed by a rash on the face and body. (Photo: Reuters/File)
Genetic analysis of recent cases of monkeypox suggests there are two distinct strains in the US, health officials said on Friday, raising the possibility that the virus has been running for some time.
US Many of the cases were caused by the same stress as Recent cases in EuropeBut some samples show a different strain, federal health officials said.
Each strain had seen US cases last year, before the most recent international outbreak was recognized.
Jennifer McQuiston of the Centers for Disease Control and Prevention said analysis of many more patients would be needed to determine how long monkeypox has been spreading in the US and elsewhere.
“I think it’s certainly possible that there may be cases of monkeypox in the United States that were previously under the radar, but not to any degree,” he told reporters on Friday.
Read | Monkeypox outbreak ‘moderate’, but large part of population vulnerable, says WHO
Monkeypox usually begins with a flu-like illness and swelling of the lymph nodes, followed by a rash on the face and body.
The disease is endemic in parts of Africa, where people have been infected by bites from rodents or small animals.
It does not usually spread easily between people.
Last month, cases began to emerge in Europe and the United States. Many – but not all – of those who contracted the virus had traveled internationally, and a growing number of health officials are investigating.
As of Friday, the US had identified at least 20 cases in 11 states. Hundreds of other cases have been found in other countries, many of which have been linked to sexual activity, in two recent waves in Europe.