Health officials in Thailand said on Thursday that they had confirmed a case of the version of mpox that prompted the World Health Organization to declare a global health emergency. It’s the second time that the new and deadlier version has been found outside Africa.
The announcement of the case in Thailand is likely to stir concerns about the virus spreading more widely, especially after the version was discovered in Sweden last week. Previously the outbreak had been concentrated in the Democratic Republic of Congo.
The version of the mpox virus detected in these recent cases is known as Clade Ib. Health officials are particularly concerned about it because it has a death rate of 3 percent, much higher than the 0.2 percent death rate observed in a 2022 outbreak.
That earlier outbreak was driven by a version called Clade IIb, which is spread predominantly through sexual contact. Men who had sex with men proved to be the most at risk, but behavioral changes and vaccinations curbed the spread.
Clade Ib appears to have spread mainly through heterosexual sex, epidemiologists have said. Another subtype, Clade Ia, has spread through household contact and exposure to affected animals in addition to sexual contact. So far, young children have been the most vulnerable to this subtype.
Thai officials said on Wednesday that the infected person was a 66-year-old European man who worked in an African country with an ongoing outbreak. They did not specify which country. The man, who has a home in Thailand, was not reported to have severe symptoms.
According to health officials, the man flew to Thailand from Africa, transiting in the Middle East, and arrived on the evening of Aug. 14. The next morning, he started to develop a fever and found small bumps on his skin.
Dr. Thongchai Keeratihuttayakorn, general director of Thailand’s disease control department, said the Thai authorities would notify the World Health Organization. In a statement, he said that because most of those infected do not have respiratory symptoms such as coughing or nasal discharge, the chance of spread was “less than Covid-19 or influenza.”
He advised people to wash their hands with soap or alcohol gel sanitizer; to avoid close contact with strangers; to avoid going to places where there were outbreaks; and to avoid rodents such as rats and squirrels from those places.
Thailand’s Department of Disease Control is monitoring 43 people who had been near or in contact with the infected man, Dr. Thongchai said. So far, none had shown any symptoms. They would be monitored for 21 days.
Anyone with fever, rashes or enlarged lymph nodes should head to the hospital immediately, he added.
Thailand is stepping up controls on travelers returning from places known to have mpox outbreaks. Such travelers will have to register with a Thai Health Pass and go through a screening process, according to Dr. Thongchai.
The controls include repeated checks on anyone with a temperature above 36.8 Celsius (98.2 Fahrenheit). Health workers will also examine such people for signs of a rash or bumps. Anyone with additional symptoms that match mpox will be separated and tested. People traveling from risky countries are encouraged to report their own symptoms.
The authorities are preparing 60 rooms for people who need to quarantine.
Since 2022, Thailand has had more than 800 reported cases of the earlier Clade IIb version of mpox. The virus, previously known as monkeypox, can spread through contact with infected animals or people, or through the consumption of contaminated meat. It can also be spread through sexual contact or transmitted in utero.
A virus endemic to Central and Western Africa, mpox spread rapidly to over 70 countries in 2022, prompting the World Health Organization to declare it a global health emergency in July of that year. Since then, it has affected nearly 100,000 people in 116 countries.
Ryn Jirenuwat contributed reporting.
Read More: Thailand Confirms Its First Case of New, Deadlier Mpox Version