Investigation on Schistosoma japonicaun infection pattern of human in different seasons in a hilly area

  Objective   To understand the pattern of human schistosoma infection among different seasons in the hilly areas under the present rural social and economic conditions so as to provide a theoretical foundation for the formulation of the strategy of Schistosomiasis control.

  Methods   About 500 permanent people aged older than 5 in Xitan village were selected randomly in the last ten-day period of Junn and September, and the first ten days of December respectively.Their stool specimen were examined with the method of Kato-Katz(three slides were made from one specimen).

  Results   The infection rate of human was generally 11.8% in Spring, 6.4% in Summer and 3.3% in F all with a significant difference among different seasons.The infection rate in Summer was significantly higher than that in Spring and F all in the population younger than 20, students in primary and middle schools, and both male and female people.For farmers, the infection rates in spring and summer were sig nificantly higher than the in autumn.For people older than 20, the infection rates reduced gradually and significantly with the seasons going.

  Conclusion   Spring is the chiefinfection season and fall is the season with the least opportunity for infection in hilly areas.