Chiang Mai is currently experiencing a severe outbreak of influenza. Since early November, a large number of school students have fallen ill with both Type A and Type B flu strains. Several schools have closed affected classrooms and shifted to online learning to curb further spread. Many children have been hospitalised with serious symptoms, causing deep concern among parents.
According to Dr. Songyot Kumchai, Head of the Communicable Disease Control Division at Chiang Mai Provincial Public Health Office, flu cases have risen sharply with the onset of winter — a seasonal trend as the cooler weather favours virus transmission.
From the beginning of 2025 up to now, Chiang Mai has reported 21,831 influenza cases — equivalent to an incidence rate of 1,342.77 per 100,000 population — twice as high as last year’s figure. The highest number of patients are school-aged children aged 5–9, followed by working-age groups 20–29 and 30–39, reflecting infections spreading in schools and workplaces where people gather in close contact. The five districts with the highest infection rates are Mueang Chiang Mai, San Sai, Doi Saket, Hang Dong, and San Kamphaeng.
Despite the sharp rise in cases, the outbreak remains mild, with no deaths reported this year — continuing a three-year streak without influenza fatalities in the province. Most patients are outpatients with mild symptoms. Surveillance data shows that the majority of current infections are caused by the Type B strain, which generally causes less severe illness than Type A.
In response, the Chiang Mai Provincial Public Health Office has instructed all healthcare facilities to intensify public risk communication and disease prevention campaigns. Officials urge residents to wash hands frequently, wear masks, maintain distance, and screen for symptoms after visiting crowded places, as well as to get vaccinated against influenza to help curb the outbreak.
