BANGKOK, Thailand – The Department of Disease Control (DDC) said there is currently no evidence that the COVID-19 variant NB.1.8.1 causes more severe illness than previously circulating strains, although health authorities continue to closely monitor its spread through nationwide surveillance systems. According to the Department of Medical Sciences, the variant has become the dominant strain circulating in Thailand. DDC Director-General Dr Montien Kanasawat said surveillance data collected between Jan. 1, 2025, and April 23, 2026, showed NB.1.8.1 accounted for 50.95% of detected cases, followed by JN.1 at 24.97% and XEC at 9.14%. The variant has been circulating in Thailand since around the middle of 2025. While NB.1.8.1 appears to be more transmissible and better able to evade existing immunity, current epidemiological and clinical evidence does not indicate a higher risk of severe illness or death.
According to the Digital Disease Surveillance system, Thailand recorded 4,156 COVID-19 cases and one death as of June 2. The highest number of reported infections was among people aged 30–39, followed by those aged 60 and older and individuals aged 20–29. Authorities said case numbers have increased over the past month in line with seasonal patterns but remain below the five-year median. The DDC said most infections continue to present symptoms commonly associated with respiratory illnesses, including fever, cough, sore throat, and runny nose. Authorities have advised the public to maintain preventive measures such as regularly washing hands, wearing masks in crowded places or when experiencing symptoms, and avoiding close contact with vulnerable groups, including older adults, people with underlying health conditions, and pregnant women. (NNT)
