Study of the combined influence of environmental factors on viability of cryptosporidium parvum oocysts in water evaluated by fluorogenic vital dyes and excystation techniques.
Using a factorial experimental design, the combined effect of salinity, temperature and storage time on the viability of Cryptosporidium parvum oocysts in water was evaluated by fluorogenic vital dyes (4',6-diamidino-2-phenylindole and propidium iodide) and an excystation technique. Salinity, storage time and their interaction seemed to be the most influential factors, whereas temperature was not a significant factor. Under unfavourable conditions (salinity 35 per thousand, storage time 40 days), even more than 20% of oocysts remain viable, indicating a high risk of infection for immunocompromised individuals.
Freire-Santos
F
F
Laboratorio de Parasitología, Departamento de Microbiología y Parasitología, Facultad de Farmacia, Universidad de Santiago de Compostela, Coruña, Spain.
Oteiza-López
A M
AM
Vergara-Castiblanco
C A
CA
Ares-Mazás
E
E
D000818:Animals; D016785:Cryptosporidium parvum; D005456:Fluorescent Dyes; D009994:Osmolar Concentration; D010274:Parasitology / Q000379:methods*; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000469:parasitology*
D005456:Fluorescent Dyes; D014867:Water