Thailand steps up mpox clade Ib surveillance after two new cases

Thailand’s Department of Disease Control (DDC) has stepped up surveillance of mpox clade Ib after two new confirmed cases were reported among people with risk factors linked to close physical contact and sexual contact with strangers.

Dr Montien Kanasawat, director-general of the DDC, said on Tuesday (May 19) that surveillance data from the Division of Epidemiology showed Thailand had recorded 1,074 confirmed mpox cases and 16 deaths in total.

During weeks 18 and 19 of the year, covering April 26 to May 9, 2026, Thailand reported two new confirmed mpox clade Ib cases.

The first patient was a Thai man who began showing symptoms on April 22 and had a risk history involving sexual contact with a stranger. The second was also a Thai man whose risk factor was prolonged close skin-to-skin contact in a crowded tourist area linked to a festival.

The DDC also received a report from an International Health Regulations coordinator about a foreign tourist who had travelled to Thailand and had a risk history involving sexual contact with a stranger in a tourist area. The reported patients were aged between 25 and 40.

The main risk factor remains close skin-to-skin contact associated with sexual activity, particularly among men who have sex with men (MSM), the department said.

Mpox clade Ib has shown signs of wider spread since it was first detected in Thailand in 2024. The country has recorded 18 cumulative mpox clade Ib cases, with no deaths. Since the beginning of 2026, six cases have been reported, also with no deaths. Four of the cases involved male patients, while most risk factors were linked to close skin-to-skin contact.

“Mpox cases continue to be detected, particularly among groups with risk behaviours. The best prevention is to avoid close skin-to-skin contact with people who have symptoms, and to avoid sexual contact with strangers or anyone with a rash or skin lesions that may suggest infection,” Montien said.

He urged the public to remain vigilant and take precautions consistently.

The DDC has instructed public health agencies at all levels to strengthen surveillance, screening and patient follow-up, particularly in tourist areas and venues considered at risk. The department is also accelerating risk communication to target groups to help reduce the spread of the disease.

Mpox can be prevented

Dr Direk Khampaen, deputy director-general of the DDC, said mpox could be prevented if people avoided risky behaviour, especially sexual contact with strangers in specific tourist venues or through meetings arranged via social media.

He also urged people to avoid close contact with anyone who has a rash or pus-filled blisters, not to share personal items, wash their hands regularly, use condoms every time they have sex, and avoid sexual contact with strangers.

People with suspected symptoms, such as fever, rash or blisters, especially around the genitals or other parts of the body, together with a risk history within the previous 21 days, should see a doctor immediately and inform medical staff of their risk history so they can receive proper diagnosis and treatment.

The DDC said Thailand had an effective surveillance and treatment system, and urged the public to have confidence in the country’s public health system while continuing to cooperate in disease prevention.