title: Efficacy of amine-based disinfectant KENO™COX on the infectivity of Cryptosporidium parvum oocysts.
abstract: Cryptosporidium parvum is a zoonotic protozoan parasite that may cause severe neonatal diarrhoea or even mortality in newborn ruminants: its oocysts are extremely resistant to normal environmental conditions and to most common disinfectants. KENO™COX, a patent pending amine-based formula, was tested for its ability to inactivate C. parvum oocysts. The Daugschies assay (2002), a standardized assay for chemical disinfection initially described for Eimeria spp., was adapted for C. parvum oocysts. KENO™COX diluted in water at 2% and 3% concentration and incubated with oocyst suspensions for 2h, allowed a significant reduction in viability, lysing 89% and 91% of oocysts respectively. Infectivity of the remaining C. parvum oocysts was assessed by inoculation to C57 Bl/6 neonatal mice. Each mouse received 2.5 μl of a suspension initially containing 500,000 oocysts before contact with KENO™COX. Six days post inoculation, the intestinal parasite load was significantly reduced by 97.5% with KENO™COX 2% compared to that of the mice inoculated with untreated parasites. KENO™COX 3% completely eliminated infectivity of oocysts. The number of oocysts remaining infectious in the inoculum treated with KENO™COX 2% was calculated from an inoculated dose-response curve: it was estimated at about 48.6 oocysts among the 500,000 oocysts initially treated corresponding to 99.99% of inhibition. These results demonstrate the high efficacy of KENO™COX against C. parvum oocysts. Combined with an appropriate method of cleaning, the application of KENO™COX may be a useful tool to reduce cryptosporidial infectious load on farm level.
authors.affiliation: Institut National de la Recherche Agronomique, Animal Infectiology and Public Health, Site 213, Centre INRA de Tours, 37380 Nouzilly, France.
authors.forename: M
authors.initials: M
authors.lastname: Naciri
authors.forename: R
authors.initials: R
authors.lastname: Mancassola
authors.forename: G
authors.initials: G
authors.lastname: Fort
authors.forename: B
authors.initials: B
authors.lastname: Danneels
authors.forename: J
authors.initials: J
authors.lastname: Verhaeghe
mesh_terms: D000588:Amines / Q000737:chemistry*; D000818:Animals; D000831:Animals, Newborn; D003457:Cryptosporidiosis / Q000517:prevention & control*; D016785:Cryptosporidium parvum / Q000187:drug effects*; D004202:Disinfectants / Q000494:pharmacology*; D004203:Disinfection; D004305:Dose-Response Relationship, Drug; D051379:Mice; D008810:Mice, Inbred C57BL; D033661:Oocysts / Q000187:drug effects; D013047:Specific Pathogen-Free Organisms
chemical_list: D000588:Amines; D004202:Disinfectants