Serological survey for antibodies to Encephalitozoon cuniculi in cats within the United States

Encephalitozoon cuniculi is an obligate intracellular microsporidian parasite that causes clinical and subclinical infection in many species. It is also considered a potential zoonotic disease. In the present study, a serological survey was conducted using samples from pet cats using an ELISA with a confirmed positive control sample from a cat with E. cuniculi related uveitis. Thirty-four of 127 serum samples or 26.8% were found to demonstrate reactivity with titers ranging from 1:32 to 1:1024. There were no significant differences by age or sex (p=0.99 and p=0.32, respectively). This is the first description of the use of an enzyme linked immunosorbent assay for the detection of E. cuniculi antibodies in cats in the United States.