[Surveillance of soil-borne nematodiasis in Yancheng City from 2016 to 2020]

To understand the prevalence of soil-transmitted nematode infections in Yancheng City from 2016 to 2020, so as to provide insights into the development of the scheme for further soil-transmitted nematodiasis surveillance.

Soil-borne nematode infections were detected using the modified Kato-Katz method (two slides for one sample) among the permanent residents living in Yancheng City from 2016 to 2020, and Enterobius vermicularis infection was additionally detected among children at ages of 12 years and lower using the adhesive cellophane-tape perianal swab method. The prevalence and intensity of human soil-borne nematode and E. vermicularis infections were descriptively analyzed.

A total of 51 259 person-time residents were detected for soil-borne nematode infections in Yancheng City from 2016 to 2020, and 48 egg-positives were identified, with a 0.09% prevalence. The soil-borne nematodes infecting residents included Ascaris lumbricoides, hookworm and Trichuris trichiura, with 0.04%, 0.05% and 0.002% prevalence rates of infections, and all infections were mild. There was a region-specific prevalence of soil-borne nematode infections in Yancheng City (χ² = 18.21, P = 0.02), with the highest prevalence seen in Funing County (0.21%), while no infections were detected in Dafeng District for five successive years. The overall prevalence of E. vermicularis infections was 0.22% among children at ages of 12 years and lower in Yancheng City.

The prevalence of soil-borne nematode infections appears a gradual decline in residents living in Yancheng City from 2016 to 2020, and is at an extremely low level. Further surveillance of soil-transmitted nematodiasis requires to be intensified targeting key regions and populations to consolidate the control achievements.