Soil-transmitted Helminthiasis, Intestinal Protozoa and Clonorchiosis Infections in Southeast China: A Cross-sectional Study

Abstract Background: The large scale epidemiology of parasitic diseases in Zhejiang Province has not been investigated since the second national survey.Methods: We investigated the distribution of three types of parasitic diseases (i.g. soil-transmitted helminthiasis (STH), intestinal protozoa, and clonorchiosis) in Zhejiang province from late 2014 to 2015. Kato-Katz technique was used for STH and Clonorchis. Sinensis detection, transparent adhesive paper anal swab was used for pinworm detection, and iodine smear was for protozoa detection. Hookworm positive samples need to be cultured for identification of Ancylostmoma duodenale or Necator americanus. Results: 23,552 participants were included in this study (19,935 from rural area and 3,617 from urban area). The overall prevalence of any intestinal helminth infection was 1.800%. Seven species of helminth were found: A.duodenale, N.americanus, Trichuris trichiura, Ascaris lumbricoides, C. sinensis, Fasciolopsis buski and pinworm. The prevalence of STH infection was 1.711% (1.941% in rural area, 0.442% in urban area). Hookworm was the most prevalent infection (1.584%). Only 2.79% children were found for pinworm infection in rural area. 0.396% of the rural participants were infected protozoa, and Endolimax nana was the most prevalent (0.231%). C. Sinensis infected only one man. 89.135% of participants had good personal hygiene habits. The awareness of C. Sinensis was 24.467% and 45.963% in rural and in urban area, respectively. Conclusions: Comparing to the second national survey, the prevalence of STH and protozoa infections declined greatly and C. Sinensis infection was still rare in Zhejiang Province. However, hookworm, especially N.americanus was still a parasitic threat to population health. More health education about fertilization and farming habits should be provided in rural areas. The awareness of hookworm and C. Sinensis should be reinforced in both rural and urban areas.