Ixodid ticks on domestic animals in Samut Prakan Province, Thailand.

The prevalence of tick-harboring domestic animals, tick density, and the species of ticks were studied throughout the year 2000, in Muang Samut Prakan, Bang Phli and Phra Pradaeng districts of Samut Prakan Province. The animals examined were Canis lupus familiaris (450), Bos indicus (cross-bred) (189), Bos taurus (30), Bubalus bubalis (171) and Sus scrofa domestica (450). The total number of collected ticks was 1,491. The pigs did not harbor ticks. The stages of ticks collected were larvae, nymphs and adults. The prevalence rates of tick-harboring were 46% (Canis lupus familiaris), 42.86% (Bos indicus, cross-bred), 33.33% (Bos taurus) and 9.35% (Bubalus bubalis). The tick densities were 2.22 (Bos indicus, cross-bred), 2.16 (Canis lupus familiaris), 1.16 (Bos taurus) and 0.36 (Bubalus bubalis). Only 2 species of ixodid ticks, Boophilus microplus and Rhipicephalus sanguineus, were found. R. sanguineus was the dominant species of tick. The percentage of R. sanguineus was 65.2% and B. microplus was 34.8%. In Muang district, R. sanguineus was the dominant species in C. lupus familiaris; in Bang Phli district, B. microplus was the dominant species in Bos indicus (cross-bred). The density of B. microplus was high in the summer season; the density of R. sanguineus was high in the winter season. The number of ticks depended on the geographic location, animal host and season.

The present situation of paragonimiasis in endemic area in Phitsanulok Province.

A cross-sectional survey and evaluation of paragonimiasis situation from endemic area in Phitsanulok Province was studied. Studies on the species and prevalence of parasites which infected people in Noen Maprang, Phitsanulok Province were also conducted during October 1999-March 2000. The sputum specimens were collected and examined to identify Paragonimus heterotremus eggs. In addition fecal samples were collected and examined for parasites by the formalin-ethyl acetate concentration technique. P. heterotremus eggs were detected in 2 out of 391 sputum specimens; a prevalence of 0.51%. A total of 584 stool specimens were obtained and examined. It was found that the prevalence of parasitic infection was 36.30%. Opisthorchis viverrini infection was the most prevalent (10.78%), followed by Strongyloides stercoralis (9.59%), hookworm (8.22%), Echinostoma spp (2.23%), minute intestinal flukes (1.54%), Taenia species (1.37%), Enterobius vermicularis (0.68%), Entamoeba coli (1.03%) and Giardia lamblia (0.86%). The prevalent rate of paragonimiasis in this endemic area in Phitsanulok Province has decreased during the past decade. However, there were other important parasite infections, especially opisthorchiasis and strongylodiasis and these should be studied further.