Effects of ozone and ultraviolet radiation treatments on the infectivity of Toxoplasma gondii oocysts.
Clinical toxoplasmosis in humans has been epidemiologically linked to the consumption of drinking water contaminated by Toxoplasma gondii oocysts. We evaluated killing of T. gondii oocysts after ultraviolet (UV) or ozone treatments by bioassay in mice and/or cell culture. A 4-log inactivation of the oocyst/sporozoite infectivity was obtained for UV fluences >20 mJ cm(-2). In contrast, oocysts were not inactivated by ozone with an exposure (Ct) up to 9.4 mg min l (-1) in water at 20 degrees C. In conclusion, UV treatment can be an effective disinfection method to inactivate T. gondii oocysts in drinking water, but ozone did not show promise in this research.
Dumètre
Aurélien
A
Centre de Recherche d'Expertise et de Contrôle des Eaux de Paris, 144 Avenue Paul Vaillant-Couturier, 75014 Paris, France.
Le Bras
Caroline
C
Baffet
Maxime
M
Meneceur
Pascale
P
Dubey
J P
JP
Derouin
Francis
F
Duguet
Jean-Pierre
JP
Joyeux
Michel
M
Moulin
Laurent
L
D000818:Animals; D001681:Biological Assay; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D006801:Humans; D007928:Lethal Dose 50; D051379:Mice; D033661:Oocysts / Q000187:drug effects / Q000528:radiation effects; D010126:Ozone / Q000494:pharmacology*; D011634:Public Health; D014122:Toxoplasma / Q000187:drug effects* / Q000472:pathogenicity / Q000528:radiation effects*; D014123:Toxoplasmosis / Q000517:prevention & control*; D014124:Toxoplasmosis, Animal / Q000517:prevention & control; D014466:Ultraviolet Rays; D014867:Water / Q000469:parasitology*; D014881:Water Supply / Q000592:standards
D014867:Water; D010126:Ozone