Environmental soil contamination with zoonotic soil-transmitted helminths in the temple grounds of Chachoengsao Province, Thailand

Abstract

Background and Aim: Soil-transmitted helminth infections are a serious public health problem. The soil is an important reservoir for several helminth species. This study aimed to estimate the prevalence of soil contamination with zoonotic soil-transmitted helminths. Materials and Methods: Soil samples were collected on the grounds of 19 temples in Ratchasan and Bang Khla districts, Chachoengsao Province, Thailand, between June 2021 and February 2022. A total of 190 soil samples were collected from ten different areas on the grounds of each temple, of which 31 (16.3%) were contaminated. The samples were analyzed by a centrifugal flotation technique using a saturated sodium nitrate solution. Results: Six genera of helminths were recovered from the soil samples, of which five genera were identified as helminth eggs and two genera were identified as helminth larvae. The prevalence of soil contamination with helminth eggs was as follows: Toxocara spp. 15.8% (30/190), hookworm/strongylid 12.1% (23/190), Trichuris spp. 6.8% (13/190), Taenia spp. 2.1% (4/190), Ascaris spp. 1.6% (3/190), and unidentified helminth eggs 5.8% (11/190). Moreover, nematode larvae consisted of 8.4% (16/190) hookworm/strongylid, 3.7% (7/190) of Strongyloides spp., and 4.2% (8/190) unidentified nematode larvae. The rates of soil-transmitted helminth contamination were not significantly different between Ratchasan and Bang Khla districts (p = 0.878). Conclusion: Soil-transmitted helminth contamination was found in the soil environment of the community temples with a high probability of spreading intestinal helminthiasis to the local residents. Therefore, public awareness campaigns should be conducted targeting people in the community to increase their knowledge and understanding about animal healthcare to prevent and control the spread of soil-transmitted helminthiasis. Keywords: soil contamination, soil-transmitted helminth, temple, Thailand, zoonotic helminth.