Changing patterns in intestinal parasitic infections among Southeast Asian laborers in Taiwan.

In order to determine whether there are changing patterns in intestinal parasitic infections among foreign laborers in North Taiwan, one fecal specimen was obtained from each of 1,569 laborers and examined by the formalin-ethyl acetate sedimentation technique. The prevalence of intestinal parasitic infections was 8.2%. Females (11.7%) had a significantly higher prevalence than males (6.9%), although there was no significant difference between Filipinos (7.7%), Thais (8.3%) and Indonesians (12.5%). Blastocystis hominis (3.4%) had the highest prevalence among the nine species of parasites detected. The significantly higher prevalence of B. hominis in the entry examination indicates an increasing trend in incoming Southeast Asian laborers. In addition, the prevalence of soil-transmitted helminth infections has become extremely low. Female laborers had a significantly higher positive rate. Although Opisthorchis viverrini/Clonorchis sinensis remains prevalent among Thais, the positive rate was also significantly reduced. These epidemiological patterns are different from those observed in previous studies and may be attributed to the long-term and constant movement of the foreign laborers.