In March 2002, we performed a small-scale survey to investigate the intestinal helminth and protozoan infection among the inhabitants of Roxas city, and formalin-ether concentration method was used to detect protozoa cysts and helminth ova.

The number of examinees was 301, and infection rate was 64.5% for helminths and protozoa. Among the positives, female showed higher positive rate (72.5%) than that of male (56.6%). The most common infected parasite was Ascaris lumbricoides (51.2%), followed by Trichuris trichiura (27.6%), hookworm (8.0%), and Enterobius vermicularis (0.3%). Intestinal protozoa infection rate was very low, except infection with Entamoeba coli (15.0%). Entamoeba histolytica and Iodoamoeba buetschlii were identified in about 1% of the samples. Multiple infection was also frequent in intestinal helminths. Among the multiple infection, A. lumbricoides and T. trichiura double infection was the most common (79.2%) of all the multiple infection. The age group of 1 to 15 years was the greatest number (87%) of the total examinees. The intestinal helminth infection rate of these school age children was considerably high. Intestinal helminths such as A. lumbricoides showed 54.3% positive rate (Table 1). It is obvious that high infection rate of A. lumbricoides would affect the growth of children, thus necessitating the medication and education against parasite infection. According to earlier studies on intestinal parasite infection in the Philippines (Cabrera, 1984; Oberst et al., 1987; Lee et al., 2000), the soil-transmitted intestinal helminths such as A. lumbricoides, hookworm, and T. trichiura show more than 30% high infection rates. The present study also revealed similar results. In the case of A. lumbricoides, 51.7% infection rate was higher than that of rural area (Yamamoto et al., 2000). Carney et al. (1981a, 1981b) reported that Mindanao and Mindoro had schistosomiasis egg positive rates of 16% and 20%, respectively. Trematodes and cestodes, however, were not detected in the present study, and the snail (Onchomelania quadrasi) is considered to be the habitat.

In summary, the intestinal helminth infection rate of school children of the Roxas city was considerably high and they require special attention to protect them from the parasitic diseases. Since this area is prevalent in intestinal helminthes, mass treatment through wide-spectrum helminthics should be carried out.