[Study on the infectivity of Angiostronglus cantonensis in the epidemic foci].
OBJECTIVE
To analyze the degrees on the epidemic foci of Angiostronglus cantonensis and to explore the measurement methods.


METHODS
Snails (Pila gigas) were collected from the spots of Wenzhou, Cangnan, Yongjia, Yueqing in Zhejiang province and Minhou, Changle, Ningde in Fujian province. The snails were examined microscopically in order to calculate their infection rates and the average worm number in the positive snails, then taking the product of multiplication of both values as infestation index.


RESULTS
The infection rates of the epidemic foci were 10.59% (9/85), 60.74% (181/298), 34.96% (79/226), 32.90% (76/231), 57.50% (184/320), 40.00% (82/205), 17.65% (12/68) and the rates of infectivity were 6.57, 183.54, 121.73, 93.45, 276.36, 76.08, 12.65, respectively.


CONCLUSIONS
The epidemic foci were divided into five ranks (super, high, mid-range, low and non-epidemic foci) according to the value of infestation index which ranked from > 75, 30-75, 5-29, < 5 to 0.
Huang
Hui-Cong
HC
Department of Parasitology, Wenzhou Medical College, Wenzhou 325035, China.
Tan
Feng
F
Li
You-Song
YS
Zhuge
Qin-Yun
QY
Ma
Xue-Lian
XL
Pan
Chang-Wang
CW
D000801:Angiostrongylus / Q000472:pathogenicity*; D000818:Animals; D002681:China; D004196:Disease Outbreaks; D012908:Snails / Q000469:parasitology*; D017206:Strongylida Infections / Q000453:epidemiology*