Objective: To explore the relationship between fecal examinations and worm collection results in a community investigation of Ascaris lumbricoides infection.
Methods: A total of 1 019 residents in Zhangxi Village, Nanchang County, Jiangxi Province were investigated with the Kato-Katz technique and worm collection after deworming.
Results: Among 1 019 residents investigated, the actual prevalence of A. lumbricoides was 30.23%, and the egg and worm positive rates were 20.41% and 23.75%, respectively. The average burden was 2.64 worms per person, and the heavier worm burden accounted for less proportion. The heavier the worm burden, the higher the probability to got egg in the feces. If one person had 7 worms or more, the probability to got eggs in his feces was 100%. Among people of false negative fecal examination, 61.00% of them were infected with male worms only, whereas 7.00% were infected with immature female worms with or without male worms, and 32.00% were infected with mature female worms with or without male worms. Totally 32.47% of infected people were missed by fecal examination, including 22.08% without egg excreted, and 10.39% missed because of the method itself.
Conclusion: The egg positive rate is obviously lower than the actual infection rate, and the egg detection rate is correlated with the worm burden.