Antibody titres against canine papillomavirus 1 peak around clinical regression in naturally occurring oral papillomatosis.

Abstract

Most forms of canine papillomatosis are believed to be associated with papillomavirus infections. Canine papillomavirus type 1 (CPV1) is considered to be responsible for most oral cases and several forms of cutaneous papillomatosis. The aim of this study was to evaluate cases of naturally occurring oral papillomatosis with regard to the type of virus involved, antibody induction and remission time. Forty dogs showing different degrees of classical oral papillomatosis were included as a single study group. Tissue and serum samples were acquired upon initial presentation; serum samples were collected again upon remission (n = 13) and after 3 months of convalescence (n = 4). None of the dogs underwent antiviral therapy. Tissue samples were tested by PCR to detect CPV DNA, while serum samples were tested using a specific enzyme-linked immunosorbent assay for antibodies against the L1 capsid protein of CPV1. All tissue samples were positive for CPV1 DNA, and 87.5% of all serum samples contained measurable levels of antibody against the virus (cut-off value 0.3). The average optical density measured in the enzyme-linked immunosorbent assay was 0.51 at initial presentation, 1.65 upon remission and 0.83 at 3 months postrecovery. Time to clinical regression varied between 1 month and 1 year. These data support existing evidence for a high prevalence of CPV1 in canine oral papillomatosis. The healing process seems to correlate with a strong antibody response, and antibody titres peaked around the time of clinical recovery. In contrast to previous data from laboratory settings, the variation in remission time was very high.