Investigation on subclinical aspects related to intestinal parasitic infections among Thai laborers in Taipei

Background: The migration of foreign workers from developing regions to developed countries may potentially lead to transmission of intestinal parasitic infections. In order to determine the relationship between intestinal parasitic infections and the health status of foreign workers, 302 Thai laborers brought to Taiwan were examined in this study. Nine species of parasites were found in 64.9% of laborers; Opisthorchis viverrini, hookworm, Strongyloides stercoralis, Giardia lamblia, Trichuris trichiura, Fasciolopsis buski, Taenia sp, Echinostoma sp, Entamoeba coli. Methods: From June 1992 to December 1993, a total of 302 Thai laborers, participating in the mandatory entry health examination at Chang-Gung Memorial Hospital, Lin-Kou Medical Center were interviewed and examined. These subjects underwent a physical examination, chest roentgenography, and serological tests for human immunodeficiency virus anti-body, syphilis (VDRL), and hepatitis B surface antigen. Results: Among the 302 Thai laborers examined, 196 (64.9%) were found to be infected with 1 to 5 species of parasites. All 193 infected Thai laborers were treated in Taiwan. Two or 3 courses of pyrantel pamoate, mebendazole, praziquantel, and metronidazole were administered to 119, 45, 24, and 5 infected patients respectively. After 1 week of treatment, all results of stool examinations were negative. Conclusion: Acquisition of infection has been determined to be related to the consumption of koipla, a dish prepared from uncooked freshwater fish. Not unexpectedly, in the present study, it was found that this species was the most important intestinal parasite among Thai laborers and was significantly associated with the consumption of koipla.