ABSTRACT
Objective To understand the epidemic situation of soil-transmitted nematodiasis in the national surveillance site in Henan Province. Methods Over 1000 fecal samples from inhabitants in Huaiyang County of Henan Province,which was a national surveillance site,were collected each year from 2006 to 2015,the eggs of soil-transmitted nematodes and other intesti-nal helminths were examined by Kato-Kats technique. The cellophane swab method was used to detect Enterobius vermicularis eggs in children aged 3 to 12 years. In addition,the soil samples were collected from vegetable fields,lavatories,courtyards and kitchens of 10 families randomly selected in each year to examine Ascaris eggs by a modified saturated sodium nitrate floatation method. Results From 2006 to 2015,10419 persons were investigated,and the eggs of five species of intestinal helminths, Ascaris lumbricoides,Trichuris trichiura,hookworm,E. vermicularis,and Trichostrongylus orientalis,were detected,The aver-age infection rate of soil-transmitted nematodes in residents in Huaiyang County was 3.69%. The intensity of infection was mild and a family clustering was obvious. Both the infection rates of E. vermicularis in children and soil-transmitted nematodes in vil-lagers had no significant differences between different genders (both P>0.05). The infection rates of soil-transmitted nema-todes,A. lumbricoides and E. vermicularis all reached the highest in the age group of 1-10 years. For different education back-ground,the people with primary school education had the highest infection rate,and the infection rate showed a decreasing trend with the increase of the educational level. The infection rate of soil-transmitted nematodes in the national surveillance site in Henan Province showed a decreasing trend from 2006 to 2015. Unfertilized and fertilized A. lumbricoides eggs were detected in the soil samples,but the positive rate was very low. Conclusions In the recent 10 years,the infection rate of soil-transmit-ted nematodes in the national surveillance site in Henan Province shows a decreasing trend and maintains at a low level. The in-fection shows a family clustering. The children,especially those aged 3-9 years are the main infected population,and E. vermic-ularis infection is the key point of prevention and control.