Thailand has reported Asia’s first case of the highly contagious and potentially more lethal Clade 1b strain of the mpox virus. Health authorities confirmed on Thursday that a 66-year-old European national, who had traveled to Thailand from Africa, was diagnosed with the new strain.
The World Health Organization (WHO) recently declared a global public health emergency due to the Clade 1b variant, which can spread through routine contact and has a fatality rate of approximately 3.6%. The strain has led to a significant surge in cases across Africa, particularly in the Democratic Republic of Congo, Burundi, Kenya, Rwanda, and Uganda, resulting in over 500 deaths since July, according to WHO data.
Dr. Thongchai Keeratihattayakorn, the director-general of Thailand’s Department of Disease Control, stated that the infected individual, who arrived in Thailand on August 14, likely contracted the virus in an endemic region, although the specific country was not disclosed. Health officials are closely monitoring 43 people who had been in contact with the patient, all of whom are currently asymptomatic. These individuals will be under observation for 21 days.
In response to the detection of Clade 1b, the Thai government has implemented new health measures. Travelers arriving from 42 designated “risk countries” are now required to register and undergo testing upon arrival in Thailand.
This case marks the second occurrence of the Clade 1b strain outside Africa, with the first being reported in Sweden.
While the WHO has emphasized the seriousness of the Clade 1b outbreak and called for increased vaccine production, it has reassured the public that this virus is not another COVID-19 pandemic. The organization noted that much is already known about mpox and how to control its spread.
The Clade 1b strain is a more severe version of the mpox virus, which saw an earlier outbreak in 2022 involving a milder variant known as Clade 2. That outbreak, which primarily affected gay and bisexual men, resulted in around 140 deaths and 90,000 cases worldwide.
Since 2022, Thailand has reported approximately 800 cases of mpox caused by Clade 2. However, this is the first time the more virulent Clade 1b variant has been detected in the country.
Mpox, caused by a virus transmitted from infected animals and spread among humans through close physical contact, leads to symptoms such as fever, muscle aches, and large boil-like skin lesions.