A Khon Kaen University doctor is concerned about the increasing liver fluke infections among Gen Z and warns that more than 10,000 people in the Northeast develop bile duct cancer annually.
At 3:00 p.m. on 7 Jul 2026 at the Medical Science Building, Faculty of Medicine, Khon Kaen University, Associate Professor Dr. Watcharin Loailom, acting director of the Bile Duct Cancer Research Institute, revealed that currently, there is an increase in liver fluke infections among Gen Z, and more than 10,000 people in the Northeast develop bile duct cancer each year.
Nowadays, with abundant media and many influencers, there are clips showing people eating raw fish and other raw foods. Recently, videos show eating fresh fermented fish with influencers—many people imitate this trend, squeezing lime and chili powder onto fermented fish before eating. This behavior has emerged recently, and infection rates are increasing in younger age groups.
Random testing of over 200,000 people in the Northeast found an average infection rate of 28.8%. Approximately one in three people tested in the Northeast are infected. When charting infection rates by age group, it was found that while previously older people had higher infection rates, now 20-30% of younger people are infected, similar to before.
"Hearing that 30% of students tested positive, am I surprised? Not at all, because this pattern has been observed for over 10 years. Since developing the test kit, we launched the Isan zero-ov campaign in collaboration with the Thai Health Promotion Foundation, focusing on Gen Z who are more exposed to media and various clips," he said.
Associate Professor Dr. Watcharin Loailom added that although commercially available cooked fermented fish in bottles is popular, some som tam (papaya salad) shops still serve fermented fish floating in the liquid. This certainly carries infection risk. Foods like fermented fish, sour fish, and spicy fermented fish salads increase the chance of liver fluke infection among Gen Z. This is not surprising, and the numbers reflect reality. With about 24 million people in the Northeast, approximately 6 million may be infected, matching the one-third infection rate found in testing.
The real danger is not the liver fluke itself but the bile duct cancer it causes. About 10,000 people in the Northeast develop bile duct cancer annually. Liver fluke infection can be treated effectively with prescribed anti-parasitic medication, but if old eating habits persist, reinfection is possible. Repeated infections increase the risk of bile duct cancer.
The test kit developed by Khon Kaen University has evolved over 15 years and resembles COVID-19 antigen tests. It has FDA approval and meets standards. To improve accessibility, the National Health Security Office has included it as a benefit. People aged 15 and over can check eligibility for a free test kit once a year via the Paotang app by answering three risk questions. If any risk is present, they can receive a test kit at participating pharmacies under the NHSO program.
Meanwhile, Mr. Wachirapant Wantong, 39, owner of Zaap Chatchen restaurant, said customers can be assured of safety when dining at his place because they use 100% boiled fermented fish from a trusted source. Since the news about infections, customer numbers have not decreased but rather increased. The restaurant boils fermented fish at 200 degrees Celsius until fully cooked. Customers can be confident about safety when eating there.
Nowadays, convenience leads people to buy bottled fermented fish, which is already cooked, and most vendors boil it before use because raw fermented fish has a fishy smell and is less fragrant than cooked fermented fish. Consumers are advised to choose safe foods, avoid eating raw or undercooked items, always cook thoroughly, and select reputable establishments for their safety.