A population-based study of the clinical, laboratory and ultrasonographic findings in patients suffering from mild or moderate
opisthorchiasis in Prachinburi province, Thailand was conducted in 1990-1992. The effectiveness of treatment with
praziquantel at 40 mg/kg
body weight was evaluated.
After treatment, a long-lasting, marked improvement in the well-being of the study group was observed. Symptoms common in
opisthorchiasis infection decreased in intensity and the clinical response showed total or partial remission in 98% of all cases studied. Total and direct
bilirubin concentrations decreased significantly and remained low up to the end of the follow-up period of 2 years, indicating a reduction in
cholestasis. Also, white blood cell counts decreased initially, which can be interpreted as a reduction in
inflammation intensity. No relationship was found between intensity of
infection and age or clinical findings. Population-based treatment of
opisthorchiasis appears to have had a significant impact on public health in north-east Thailand. However, it is also evident that
drug therapy alone will not solve the
opisthorchiasis problem, as indicated by the
reinfection rate of almost 10% at the end of the study.