Detection of Toxoplasma gondii-like oocysts in cat feces and estimates of the environmental oocyst burden.
OBJECTIVE
To estimate the analytic sensitivity of microscopic detection of Toxoplasma gondii oocysts and the environmental loading of T gondii oocysts on the basis of prevalence of shedding by owned and unowned cats.


METHODS
Cross-sectional survey.


METHODS
326 fecal samples from cats.


METHODS
Fecal samples were collected from cat shelters, veterinary clinics, cat-owning households, and outdoor locations and tested via ZnSO(4) fecal flotation.


RESULTS
Only 3 (0.9%) samples of feces from 326 cats in the Morro Bay area of California contained T gondii-like oocysts. On the basis of the estimated tonnage of cat feces deposited outdoors in this area, the annual burden in the environment was estimated to be 94 to 4,671 oocysts/m(2) (9 to 434 oocysts/ft(2)).


CONCLUSIONS
Despite the low prevalence and short duration of T gondii oocyst shedding by cats detected in the present and former surveys, the sheer numbers of oocysts shed by cats during initial infection could lead to substantial environmental contamination. Veterinarians may wish to make cat owners aware of the potential threats to human and wildlife health posed by cats permitted to defecate outdoors.
Department of Pathology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Haydee A
HA
Dabritz
Melissa A
MA
Miller
E Robert
ER
Atwill
Ian A
IA
Gardner
Christian M
CM
Leutenegger
Ann C
AC
Melli
Patricia A
PA
Conrad
D000818:Animals; D000829:Animals, Domestic; D002371:Cat Diseases / Q000175:diagnosis / Q000453:epidemiology*; D002415:Cats; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D004787:Environmental Pollution; D005243:Feces / Q000469:parasitology*; D005260:Female; D008297:Male; D016017:Odds Ratio; D033661:Oocysts; D010270:Parasite Egg Count / Q000662:veterinary; D016133:Polymerase Chain Reaction / Q000662:veterinary; D015995:Prevalence; D014122:Toxoplasma / Q000302:isolation & purification*; D014124:Toxoplasmosis, Animal / Q000175:diagnosis / Q000453:epidemiology*