[Trends of soil-transmitted nematode infections in Jiangxi Province].

OBJECTIVE: To analyze the status and trends of soil-transmitted nematode infections in Jiangxi Province from 1989 to 2014, so as to provide the evidence for generating the strategy of soil-transmitted nematode prevention and control.

METHODS: The data of three epidemiological surveys on human parasitic diseases (in 1989, 2002 and 2014) were classified and analyzed. The stool examination by Kato-Katz's thick smear method was adopted for the investigation of soil-transmitted nematode infections.

RESULTS: The total infection rate of soil-transmitted nematodes decreased by 91.89% from 77.67% in 1989 to 6.30% in 2014, in which the infection rate of Ascaris lumbricoides decreased by 98.78% from 71.11% to 0.87%, the infection rate of Trichuris trichiura decreased by 96.80% from 29.67% to 0.95%, and the infection rate of hookworm declined by 73.57% from 17.63% to 4.66%. The infection rates of soil-transmitted nematodes in the female were higher than those in the male in three surveys. In different ecological districts, the infection rates of soil-transmitted nematodes in the female were also higher than those in the male, except in Zhe-Min Ecological District in 2002 and 2014. A declined trend of the infection was showed in all age-groups in the three surveys, but it slowed down by the growth of age, i.e., the reduction rate was 97.03% in the age group of < 10 years while 80.62% in the age group of >70 years. In 2014, the number of persons infected with soil-transmitted nematodes occupied 65.4% of the whole number of persons infected with intestinal parasites.

CONCLUSIONS: The mean infection rates of soil-transmitted nematodes decrease obviously in human population in different ecological districts, but the soil-transmitted nematodes are still the main species in intestinal parasite infections. The sequence of dominant species changes from A. lumbricoides , hookworm and T. trichiura in 1989 to hookworm, T. trichiura and A. lumbricoides in 2014. The rural female and elder people are the key population, while hookworm is the key species for the prevention and control of soil-transmitted nematodes.