Social and behavioral factors associated with Clonorchis infection in one commune located in the Red River Delta of Vietnam.

Social behavioral factors associated with Clonorchis infection are needed for control measures. The population in Nga Tan commune were randomly sampled and questioned to determine knowledge, perception, and health behavioral factors associated with Clonorchis infection among heads of households. The cellophane thick smear method was applied to examine their stool samples. Seven hundred and seventy-one cases were examined, the positive rates were 17.2%, 66.9%, 78.7%, 15.9%, and 0.14% for Clonorchis sinensis, Ascaris lumbricoides, Trichuris trichiura, hookworm, and Dicrocoelium dendriticum respectively. There was no significant difference between the infection rate of clonorchiasis, education level, and family income groups (p > 0.05). But there was significance difference between the infection rate of clonorchiasis and people living in different family sizes (p < 0.01). Thirty-four clonorchiasis patients treated with praziquantel 25 mg/kg/day for three days showed a cure rate in 30 days of 97.1%.

Epidemiology, symptoms and treatment of paragonimiasis in Sin Ho district, Lai Chau province, Vietnam.

Sin Ho is a district of the northern mountainous province of Lai Chau, Vietnam, where the people have the habit of eating undercooked crabs. A study on paragoniamiasis carried out from 1994 to 1995 with 1,642 persons in this endemic area, showed that the rate of eating raw-crab was 72.5%. Crab examination (Ranguna kimboiensis) showed an infection rate of Paragonimus metacercaria of 98.1%. With 624 stool samples examined by Kato technique, the infection rate of Paragonimus in humans was 6.4%. With 338 sputum samples examined by direct and centrifuge methods, the infection rate of Paragonimus was 7.4%. Most of the patients were children (63.2%). The infection rate of Paragonimus in dogs was 18.2 - 33.3%. Adult worms, collected from the dogs in the field and from the cats in laboratory, were identified as Paragonimus heterotremus. The main symptoms of Paragonimus patients were cough and hemoptysis (92%), discontinuously developed (96%), without fever (94%), chest pain (70%), pleural effusion (26%), neurogical symptoms (8%), eosinophilia (88.9%), nodular ring shadows in the lungs, as shown by chest X-ray examination and more in lower lobe, (76.2%). Paragonimiasis patients were treated by (a) Praziquantel 25 mg/kg/day x 3 days; the cure rate was 68.8%. (b) Praziquantel 50 mg/kg/day x 3 days; the cure rate was 75%.