Health Authorities Warn of “Scrub Typhus” Outbreak in Late Rainy Season  Farmers and Tourists at High Risk from Chigger Bites

October marks the start of the scrub typhus outbreak season in Thailand, as humid weather and cooler temperatures create ideal conditions for chigger mites—the disease vector—to thrive. Combined with increased outdoor activities such as trekking, camping, and farming during the late rainy and early winter months, the risk of infection rises significantly.

According to the Department of Disease Control’s surveillance system, between January 1 and October 8, 2025, there were 6,688 reported scrub typhus cases nationwide, with 5 deaths. The provinces with the highest incidence were Mae Hong Son, Nan, Roi Et, Chiang Mai, and Chiang Rai. In Health Region 7 (Khon Kaen, Maha Sarakham, Roi Et, and Kalasin), 477 cases were recorded, with Roi Et province reporting the most patients.

Scrub typhus is a bacterial infection transmitted through bites from infected chigger mites, which typically live in tall grass, scrubland, forests, and rice fields. The mites often use rodents as their natural reservoir. After infection, symptoms usually appear within 10–12 days and may include prolonged high fever, chills, headache, muscle pain, fatigue, cough, nausea, vomiting, and sometimes red eyes. A characteristic black scab at the bite site, resembling a cigarette burn, may also appear. If untreated, the disease can lead to severe complications such as pneumonia, meningitis, or encephalitis, which can be fatal.

Prevention Tips:

  - Wear long-sleeved shirts and long pants when entering high-risk areas.

  - Apply insect repellents to skin and clothing.

  - Avoid sitting or lying directly on grass or soil.

  - After outdoor exposure, shower promptly, wash hair, and launder clothes thoroughly with soap and detergent.

  - Maintain cleanliness around homes and farms by trimming grass, tilling soil, and reducing rodent populations.

Authorities urge farmers and outdoor travelers to take special precautions. Anyone experiencing high fever, headache, body aches, rash, or eye redness—particularly with a black scab-like wound—should seek immediate medical care and inform doctors about recent exposure to forest or field environments. Self-medication with antibiotics is strongly discouraged, as it may delay accurate diagnosis and treatment.

 

Source:

Department Of Disease Control