早在1939～1945年战争时期,英国头虱的发生率高达30%,通过卫生人员的积极防治,至1947年降为约18%。其后20年,发生率稳定地降至很低的水平,这可能是由于使用新的有效的杀虫剂特别是丙种——六六六的结果。但70年代初,头虱发生率开始升高。最近(1976年)的估计,英格兰受侵染的儿童有25万,相当于学校全体学生的3%左右。值得注意的是其他国家的头虱发生率也有升高。1976年有二位作者提出,法国学龄儿童患虱病者高达50～60%,并提到在苏联也有类似情况,在丹麦及荷兰1970年前头虱的发生率每年不到10例,而1975年则增加到150例以上。在1965～1970年间西 As early as the 1939-1945 war, the incidence of head lice in the United Kingdom was as high as 30%. By 1947, the active prevention and control of health workers was reduced to about 18%. In the following 20 years, the incidence steadily dropped to a very low level, possibly due to the use of new and effective pesticides, especially Type C - BHC. However, in the early 1970s, the incidence of head lice began to rise. According to a recent (1976) estimate, there are 250,000 children infected in England, equivalent to about 3% of all school pupils. It is noteworthy that the incidence of head lice in other countries also increased. In 1976, two authors suggested that as many as 50-60% of French school-age children suffer from louse disease and mentioned similar cases in the Soviet Union. The incidence of head lice in Denmark and the Netherlands was less than 10 cases per year in 1970, while in 1975 Then increased to more than 150 cases. Between 1965 and 1970 West