Time and temperature effects on the viability and infectivity of Cryptosporidium parvum oocysts in chlorinated tap water.
The authors compared the viability and infectivity of Cryptosporidium parvum oocysts in chlorinated tap water at various storage durations (i.e., 2 wk, 4 wk, 6 wk, or 8 wk) and at 2 cool temperatures (i.e., 10 degrees C and 4 degrees C), using in vitro (excystation) and in vivo (suckling mouse) methods. After 8 wk, mean oocyst excystation decreased to 33.4% and 26.7% at 10 degrees C and 4 degrees C, respectively. Suckling mice infectivity was higher after storage at 10 degrees C than after storage at 4 degrees C. These data suggest that Cryptosporidium parvum oocysts can survive and remain infectious for 8 wk in cool chlorinated tap water.
Li
Xunde
X
Laboratory of Medical Parasitology, Faculty of Medicine-Pharmacy, Rouen, France.
Brasseur
Philippe
P
Agnamey
Patrice
P
Ballet
Jean Jacques
JJ
Clemenceau
Chu
C
D000818:Animals; D000831:Animals, Newborn; D001681:Biological Assay; D016785:Cryptosporidium parvum / Q000472:pathogenicity* / Q000502:physiology; D051379:Mice; D033661:Oocysts; D013534:Survival; D013696:Temperature; D013997:Time Factors; D014881:Water Supply