OPISTHORCHIS-VIVERRINI INFECTION IN THAILAND - STUDIES ON THE MORBIDITY OF THE INFECTION AND RESOLUTION FOLLOWING PRAZIQUANTEL TREATMENT

A community study on opisthorchiasis was conducted in Prachinburi Prov ince in eastern Thailand during 1990-1992. The morbidity from opisthor chiasis in the community and reversibility of biliary pathology follow ing treatment with praziquantel at a single dose of 40 mg/kg were asse ssed by longitudinal investigations of clinical laboratory, and ultras onographic changes. A total of 913 voluntary subjects infected with Op isthorchis viverrini were randomly selected for longitudinal study, an d 579 subjects without liver duke infection were recruited as controls . The majority of the study group suffered from mild and moderate infe ctions that were associated with nonspecific gastrointestinal symptoms . Grade I and II ultrasonographic changes, which indicated chronic inf lammation of the biliary tract and gallbladder, were detected in 32% o f the infected individuals. Clinical symptoms and ultrasonographic cha nges were common in subjects 21-40 years of age and older. Satisfactor y resolution of morbidity was observed during two years follow-up on d ays 0, 60, 180, 360, and 720, as shown by significant clinical improve ment, normalization of laboratory parameters, and downgrading of ultra sonographic abnormalities. Portable ultrasonography has proved to be a reliable noninvasive technique in the evaluation of the morbidity due to opisthorchiasis in rural areas.