Liver Fluke Tests Show High False Positives in University Screening
Thailand's health ministry will review urine testing kits for liver flukes after a university screening found high false positive rates, with only 4 confirmed infections among 380 positive urine tests. Officials say stool examination remain
On July 14, Dr. Somruk Cheusamuan, Permanent Secretary of the Public Health Ministry, announced after the 4th National Communicable Disease Committee meeting that authorities will jointly review technical guidelines for urine testing kits and care protocols for positive cases. The ministry's current standard treatment policy covers only patients with confirmed parasitic eggs found in stool samples, while a proposal to treat patients based on urine test results requires further academic review.
The urine test kit was originally developed and evaluated in laboratory settings using samples from high-infection areas, but its sensitivity and accuracy may change in regions with lower disease prevalence. Disease surveillance data shows an average prevalence of only 5%, requiring real-world field performance assessment before adoption as a standard diagnostic tool. Dr. Somruk noted that while the urine test's development had good intentions—stool examination is cumbersome and people are often reluctant to cooperate—it remains in the field evaluation phase and cannot yet replace standard testing methods.
The ministry's primary concern is cholangiocarcinoma (bile duct cancer), which is linked to long-term liver fluke infection. Officials are advancing parallel strategies including screening in high-risk areas for early cancer detection and public campaigns against risky behaviors such as consuming undercooked or raw food, alongside developing more convenient and effective screening tools before implementing them in routine healthcare services.
Dr. Niti Hattanurak, Deputy Director-General of the Disease Control Department, reported that of 380 students testing positive with the urine kit, 292 underwent stool examination, revealing only 4 confirmed liver fluke infections and 11 other parasitic infections such as roundworms. This discrepancy reflects differences between the two testing methods, reinforcing reliance on the World Health Organization's stool examination as the diagnostic standard.
Dr. Yongjuea Laeosiritathorn, Director of the General Communicable Diseases Division, clarified that the ministry continues to use stool examination as the primary screening method and provides treatment only to confirmed cases, while the urine test serves as preliminary self-screening. Positive urine results require confirmatory stool testing.
