Survey of Sparganum mansoni infection in frogs and snakes in Hangzhou

Objective To develop preventive strategies for Sparganosis mansoni in Hangzhou based on the analysis of the natural infection of Sparganum mansoni in frogs and snakes. Methods Wild frogs (671) and snakes (3) were captured from all 7 rural areas in Hangzhou and artificial breeding bullfrogs (80) were bought from 5 urban markets. The specimens were dissected to detect Sparganum mansoni. Results Of 671 wild frogs,a total of 209 (31.15%) were infected with Sparganum mansoni (1 to 60 worms per frog.),and 3 wild snakes were all infected with Sparganum mansoni (2 to 99 worms per snake). For 80 artificial breeding bullfrogs,the detection results were negative. Sparganum could be detected in the muscles of any site in frogs,and the infection rate in leg muscles was 78.99% (391/495),but in snakes,sparganum mainly parasitized in subcutis with the positive rate of 61.21% (71/116). The differences on infection rates of frogs with different size was significance (χ2=6.561,P0.05). Conclusion The infection rate of Sparganum mansoni in wild frogs and snakes was relatively high. These frogs and snakes widely distribute in Hangzhou,and the natural focis of sparganosis mansoni do exist. It is necessary to conduct the prevention of sparganosis by improving life style and changing diet habit of the people.