Intestinal parasites of man in Northern Bohol, Philippines, with emphasis on schistosomiasis.

A survey for intestinal parasites with emphasis on Oriental schistosomiasis was conducted in the townships of Trinidad and Talibon, Bohol Province, Philippines and approximately 1,700 stool samples were examined. Schistosoma japonicum is still endemic to these areas of northern Bohol but infection rates were much lower than expected, 5% rather than 30%. Soil-transmitted helminths were the most common parasitic infections. Hookworms were found in 71% of the samples tested, most infections were due to Necator americanus 97% and Ancylostoma duodenale accounted for only 3%. Trichuris trichiura and Ascaris lumbricoides eggs were diagnosed in 58% and 45% respectively of the fecal samples examined. Other helminths and protozoan parasites detected were Enterobius vermicularis, Stronglyoides stercoralis, Entamoeba histolytica, Entamoeba hartmanni, Entamoeba coli, Endolimax nana, Iodamoeba bütschlii, Giardia lamblia and Chilomastix mesnili.