蛔虫病是我国最常见的寄生虫病。蛔虫感染遍及我国各地，据１９８８—１９９２年全国抽样调查的感染率平均为４７．０％，估计全国感染人数达５．３１亿，南方诸省感染率尤高。作为传染源的人感染虫数愈多，污染环境愈严重。一条雌蛔虫每天约产卵２４万个，我们生活的外界环境? Ascariasis is the most common parasitic disease in our country. Roundworm infections spread all over China. According to the national sample survey from 1988 to 1992, the average infection rate was 47.0%. An estimated 531 million people were infected nationwide. Infection rates in the southern provinces were particularly high. As a source of infection, the more infected people, the more serious the pollution of the environment. A female roundworm eggs about 240,000 a day, the external environment of our life?