[Sensitivity of Oncomelania snail to niclosamide in China].
OBJECTIVE
To understand the variation in response of Oncomelania hupensis to niclosamide.


METHODS
Snails were collected from 37 sampling areas distributed in 10 provinces (municipalities) using random environmental sampling methods in accordance with the different types and categories of snail habitats. In laboratory the snails were immersed in solutions of niclosamide for 24 and 48 hours at 25 degrees C.


RESULTS
1.0 mg/L niclosamide showed 100% killing effect on snails in 24 hours. The LC50 concentrations for snails immersed for 24 hours ranged from 0.0320 to 0.1689 mg/L with a mean value of 0.0920 mg/L. 0.5 mg/L niclosamide showed 100% killing effect on snails in 48 hours. The LC50 values for snails immersed for 48 hours ranged between 0.0299 and 0.1114 mg/L with a mean of 0.0627 mg/L. There is a significant difference in snail sensitivity to niclosamide between sampling areas.


CONCLUSIONS
The sensitivity to niclosamide varied in snails from different sampling fields, but the chemical in a concentration of 1.0 mg/L showed 100% effect of killing snails, which is consistent to the manual of schistosomiasis control.
Dai
Jian-rong
JR
Jiangsu Institute of Parasitic Diseases, Wuxi 214064.
Zhou
Xiao-nong
XN
Liang
You-sheng
YS
Zhang
Yan-ping
YP
Jiang
Yu-ji
YJ
Xi
Wei-ping
WP
Huang
Yi-xin
YX
Chen
Chang
C
Huang
Ming-xi
MX
Zhu
Yin-chang
YC
D000818:Animals; D002681:China; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D007928:Lethal Dose 50; D008975:Molluscacides / Q000494:pharmacology*; D009534:Niclosamide / Q000494:pharmacology*; D012494:Sampling Studies; D012908:Snails / Q000187:drug effects*
D008975:Molluscacides; D009534:Niclosamide