Regional seroprevalence of Cryptosporidium parvum-specific IgG of cats in the United States

Abstract The objective of this study was to determine the regional prevalence of Cryptosporidium parvum -specific IgG in the sera of cats in the United States. The continental United States was partitioned into eight regional areas. Serum samples from 75 cats from each region were assayed for C. parvum -specific IgG using an indirect enzyme-linked immunosorbent assay (ELISA). Age, sex, breed, and indoor/outdoor status were examined as possible risk factors for developing a positive C. parvum -specific IgG antibody titer. The presence of gastro-intestinal signs and Toxoplasma gondii -specific IgG in the serum were also evaluated for association with C. parvum seropositivity. Of the 600 samples assayed, 50 (8.3%) were positive for C. parvum -specific IgG. Regional seroprevalence ranged from 1.3% in the mid-Atlantic states to 14.7% in the south-eastern states. The oldest group of cats (>10 years) had the highest seroprevalence (15.3%). The prevalence of C. parvum -specific IgG was higher among male (10.1%) than among female cats (6.9%), although, the difference was not statistically significant ( p  = 0.17). Seropositivity was not associated with pure-bred status. C. parvum -specific IgG antibodies was detected most frequently in T. gondii -specific IgG seropositive cats, outdoor cats, and cats with gastro-intestinal signs. These results suggest that cats in the United States are commonly exposed to C. parvum .