Maha Sarakham freshmen hit by liver flukes - governor probes ‘som tam’ shops

Maha Sarakham governor orders urgent probe into papaya salad vendors after a shocking health screening revealed that 33% of freshmen at Maha Sarakham University are infected with liver flukes, a parasite linked to raw fermented fish (pla ra).

Suksan Sirisuriyasuntorn, head of the Communicable Disease Control Division at the Maha Sarakham Provincial Public Health Office, disclosed the alarming findings on Tuesday. A screening of 20,000 residents across the province found an overall liver fluke infection rate of 11%.

The figures were even higher among newly enrolled university students. Of the 12,733 freshmen screened at Maha Sarakham University for the 2026 academic year, 4,233 students, or 33%, tested positive for liver fluke infection.

A similar screening at Rajabhat Maha Sarakham University found that 380 of 1,922 freshmen (19%) were also infected.

Maha Sarakham Governor Chumpit Decharat has ordered provincial health officials to implement immediate countermeasures. He said the younger generation's fondness for papaya salad made with unpasteurised or non-Thai FDA-approved fermented fish (pla ra) is the likely cause, as improperly prepared fermented fish can carry liver fluke parasites.

Assoc. Prof. Nittaya Wannakit, Vice President for Student Development and Corporate Image at Maha Sarakham University, expressed shock at the findings.

She said the university had not anticipated such a high infection rate among the incoming class and called for all 50,000 students and staff members to be screened.

She noted that most of the students are from the Northeast, where dishes containing raw or under-fermented fish are dietary staples. However, it remains unclear whether the fermented fish used by local vendors is prepared safely or certified to meet food safety standards.

The university plans to launch an urgent campaign inviting vendors from campus cafeterias and the nearby Talat Noi market to undergo food safety training.

The initiative aims to educate vendors about the serious health risks associated with serving raw or improperly fermented fish, which can cause liver fluke infection and significantly increase the long-term risk of cholangiocarcinoma (bile duct cancer).

Meanwhile, Public Health Minister Pattana Promphat said today that more tests are required to confirm whether the freshmen at Maha Sarakham University are actually infected with liver flukes.

He said that the freshmen were administered with urine strip screening tests, which are a new technique producing a quick result, similar to the use of the ATK technique for tests for COVID-19 infection.

For the sake of accuracy and reliability, he said that the use of the Kato-Katz thick smear test, which is a standard laboratory technique to detect and count the eggs of parasite worms in human stool samples, should be administered.