Seroepidemiology of five major zoonotic parasite infections in inhabitants of Sidoarjo, East Java, Indonesia.

We conducted a seroepidemiological survey of zoonotic parasite infection in inhabitants of East Java, Indonesia. The subjects of the survey were 244 persons selected from visitors to Sidoarjo City Hospital in East Java between May 1992 and October 1993. Ninety-seven had diarrhea and the rest came to the hospital for routine check-ups. All serum samples were tested for antibodies against five zoonotic parasites: Toxoplasma gondii, Entamoeba histolytica, Toxocara canis. Angiostrongylus cantonensis, and Anisakis species. Tests used were enzyme-linked immunosorbent assays (ELISA), latex agglutination (LA) test, indirect fluorescence antibody (IFA) test, hemagglutination (HA) test, and gel diffusion precipitation (GDP) test. Some 64% of the subjects had antibodies to T. gondii. The prevalence of antibodies to E. histolytica varied from 2 to 15% depending on the test, but the true rate was probably the 7% or 8% obtained by the HA and IFA tests. The proportions of subjects with positive results were 63% for T. canis, 17% for A. cantonensis, and 11% for the Anisakis spp. The prevalence of antibodies to T. gondii and T. canis was lower in subjects aged 1 to 9 years than in older subjects, probably because the persons in this group had less time to be infected. Antibody titers to A. cantonensis and the Anisakis spp. were high in the juvenile group, perhaps because recent changes in eating habits have increased opportunities for infection.

Contamination of soil with parasite eggs in Surabaya, Indonesia.

Soil was examined for contamination by parasite eggs in Surabaya Indonesia. Surveys were carried out on three occassion; July, 1993 (dry season), March, 1994 (rainy season), and August, 1994 (dry season). Throughout the study, five species of nematode eggs (Ascaris lumbricoides, Toxocara cati, Trichuris trichiura, Physaloptera sp, Capillaria sp), two species of cestode eggs (Hymenolepis diminuta, Spirometra erinacei), and one species of protozoa oocyst (Isospora felis) were detected. The contamination rate and number of species found from the soil were significantly different in the dry and rainy seasons. In the dry season, the prevalence was 8-20%, with two to four species detected. During the rainy season, this rate was 83% with eight species, suggesting parasite infection to possibly occur mainly in this season. The reason for this seasonal difference may be that, in spite of constant temperature around 27 to 29 degrees C throughout the year, rainfall in the dry season in only a few percent of that of the rainy season. We concluded that parasite eggs die during the dry season owing to dryness of the soil. Contamination of soil with parasite eggs and the number of species found were greater in alley-ways and at communal water supply sites around residential areas than in open-air parks or sandy beaches. The method used in the present study proved extremely effective for ascertaining the actual dynamics of parasite infection in a certain region.