Prevalence of intestinal parasitic infections in military personnel and military dogs, Thailand.

OBJECTIVE To determine the prevalence of intestinal parasitic infections and risk factors among military personnel and military dogs at the Military Dog Center, Veterinary and Remount Department, Royal Thai Army, Thailand. MATERIAL AND METHOD A cross-sectional study was conducted in January 2006 to examine intestinal parasitic infections using wet preparation and, formalin-ethyl acetate concentration. Modified acid fast and gram-chromotrope stains were used to identify Cryptosporidium spp. and microsporidia, respectively. Culture for Blastocystis was performed using Jone's medium. Genotypic characterization of Blastocystis and Giardia duodenalis were also determined using PCR-RFLP. To determine the risk factors and outcomes of intestinal parasitic infections, standardized questionnaires were used in the present study. RESULTS Of 317 military personnel, the prevalence of intestinal parasitic infections was 22.4%. Blastocystis was the most predominant intestinal protozoa infection of 14.5% while G. duodenalis was only 1.3%. The prevalence of other helminthic infections were 4.8% which were Strongyloides stercoralis (2.5%), Hookworm (1.0%), Opisthorchis viverrini (1.0%), and Taenia spp. (0.3%), respectively. Blastocystis subtype 1 was identified in 25 positive culture specimens while all 4 positive of G. duodenalis were analyzed as Assemblage B, subgenotype IV. The presented data could not indicate that intestinal parasitic infections and blastocystosis in this army population were significantly linked to risk association among groups with regard to rank, age group, working unit, area of residence, animal contact, source and treatment of drinking water. Of 189 military dogs, the prevalence of intestinal parasitic infections was only 3.7% which was Blastocystis sp. (2.6%), S. stercoralis (0.5%), and Entamoeba coli (0.5%), respectively. CONCLUSION The predominant intestinal parasites found in this population, such as Blastocystis sp. and G duodenalis transmit to humans via fecal-oral route so that improvement of sanitation and personal hygiene should be emphasized.