Analysis of the monitoring results for soil-transmitted nematode infections in Hainan Province during 2006-2010

Objective To observe and understand the epidemic dynamics and influence factors of soil-transmitted nematode infections,thus to predict the epidemic trend and provide scientific basis for the development of control strategies and measures.Methods During 2006-2010,the number of annual monitoring persons was not less than 1000 in the Mao Yang,Wuzhishan City.The improved Kato thick smear method was applied to detect the eggs of soil-transmitted nematodes and transparent tape anus wiping method to check ova of pinworm in 3-12 years old children.Ascaris eggs in soil were tested by modified saturated sodium nitrate floatation method.The monitoring data were statistically analyzed.Results The total rate of infection with soil-transmitted nematodes decreased from 51.02％ in 2006 to 27.97％ in 2010.The total rate of decline was 45.18％ while the infection rates of hookworm,roundworm and whipworm decreased from 43.81％,3.88％ and 10.54％ in 2006 to 25.94％,0.19％ and 2.03％ in 2010,decreased by 40.79％,95.10％,80.74％,respectively.The eggs arithmetic mean and geometric mean in infected individuals and populations were decreased year by year.Severe and multiple infection of all species of nematodes also decrease year by year.But the infection rates in elderly people,farmers and illiteracy were 62.77％,33.24％,and 63.64％respectively,still at a higher level.There was no difference in pinworm infection in children with the average infection rate 39.79％.Conclusion The soil-transmitted nematode infection rate was decreased year by year.But the infection rate of hookworm in farmers was still high,so the comprehensive prevention and control measures must be implemented. Key words: Nematode infection; Soil-transmitted nematode; Infection rate; Decline rate; Infectiosity