DDC urges calm over Singapore Covid spike, says NB.1.8.1 already dominant in Thailand

Thailand’s Department of Disease Control has urged the public not to panic over Singapore’s latest Covid-19 spike, saying the NB.1.8.1 variant behind much of the concern has already been circulating in Thailand and is now the country’s dominant strain.

DDC director-general Dr Montien Kanasawat said Thailand recorded 3,642 cumulative Covid-19 cases and one death from January 1 to May 23, 2026. Reported cases have risen over the past month, but the number remains below the five-year median, he said.

Variant already found in Thailand

Health officials said NB.1.8.1 is not a new threat suddenly entering Thailand from abroad, as the variant has already been detected in the country and now accounts for 50.95% of sequenced samples.

Data from the Public Health Research Institute under the Department of Medical Sciences, covering January 1, 2025 to April 23, 2026, showed NB.1.8.1 was followed by JN.1 at 24.97% and XEC at 9.14%.

Most Covid-19 patients reported in Thailand this year were aged 30-35, followed by those aged 60 and above, and people aged 20-29.

Singapore surge puts variant in spotlight

The public concern followed a sharp increase in Covid-19 cases in Singapore, where the Communicable Diseases Agency reported 12,700 cases during the week of May 10-16, up from around 8,000 the previous week.

Singapore also saw average daily hospitalisations rise from 56 to 73, while ICU cases remained low at about one patient per day. The agency said public hospitals could manage the increase.

NB.1.8.1 was reported as the main circulating variant in Singapore, accounting for more than half of locally detected cases.

Spreads faster, but no evidence of greater severity

Dr Montien said NB.1.8.1 is a descendant of the JN.1 variant and carries several additional mutations on the spike protein.

These changes may make the virus easier to transmit and better able to evade immunity. However, he stressed that there is still no evidence that NB.1.8.1 causes more severe illness.

The DDC said Thailand also saw Covid-19 cases and cluster outbreaks increase during April-June 2025, with NB.1.8.1 identified as the main variant during the same period.

Officials urge vigilance during respiratory disease season

DDC deputy director-general Dr Direk Khampaen said Covid-19 in Thailand is now treated as an endemic or seasonal communicable disease.

Although the overall severity and transmission trend have declined, he said people should continue basic precautions, particularly during the monsoon season, when respiratory illnesses tend to spread more easily.

The DDC advised people to wash their hands regularly, wear a mask in crowded places, cover their mouth and nose when coughing or sneezing, and avoid close contact with people showing respiratory symptoms.

Officials also urged people with fever, cough or a runny nose to take an ATK test and avoid contact with vulnerable groups, especially young children, elderly people and those with underlying diseases. Anyone who tests positive should seek medical advice promptly.