Abstract:

Objective To investigate the infection status of human soil-transmitted helminths (STH) in rural areas of Guizhou Province so as to provide scientific basis for formulating the prevention and control measures for these diseases in the province. Methods The study was performed according to the National Survey Program and Implementation Rules for the Status of Human Key Parasites in 2015. Total 30 survey sites were selected from 12 counties (cities or districts) based on the stratified cluster random sampling method. No less than 250 permanent villagers in each site were enrolled in the survey. The fecal samples were collected from each participant and the eggs of STHs (Ascaris lumbricoides, hookworm, whipworm and Enterobius vermicularis) were examined under microscope using Kato-Katz technique. The eggs of E. vermicularis were examined using transparent adhesive tape around anuses of children with age of 3-6 years old. Results A total of 7 572 residents were investigated with STH infection rate of 14.9% (1 127/7 572). The infection rates of A. lumbricoides, whipworm, hookworm, and E. vermicularis were 8.1% (614/7 572), 2.2% (163/7 572), 6.3% (477/7 572) and 0.3% (21/7 572), respectively. Among the 12 counties surveyed, the infection rate of STH in Zhenfeng County was the highest (30.8%, 160/519), while that in Sinan County was the lowest (5.2%, 13/250), with statistical significance in different counties (P < 0.01). The infection rate of STH in males was 12.6% (472/3 756), which is lower than that in females (17.2%, 655/3 816) with statistical difference (P < 0.01). The STH infections were found in all age groups with the highest infection rate in the age group over 70 years old (21.0%, 111/528). Farmers as well as herdsmen and fishermen, possessed the highest infection rate of 15.8% (780/4 946) compared with people with other occupations. People in Gelao ethnic group owned higher STH infection rate of 22.9% (63/275) than people with other ethnic groups. In terms of education, the STH infection rate was highest among illiterate residents (18.9%, 214/1 133). There was statistical difference in infection rates among the residents with different age groups, occupations, nationalities and education levels (P < 0.01). Conclusion A. lumbricoides and hookworm are the main soil-transmitted helminths that infect people in rural areas of Guizhou Province. There are obvious regional distribution. Female with age over 70, farmers including hersman and fisherman, Gelao minority ethnic group and illiterate people are the main population with high infection and therefore the major control targets.

Key words: Soil-transmitted helminth, Infection, Investigation, Guizhou Province