Systematic Veterinary Virology

PATHOGENESIS

• The viruses are widespread in nature and infect birds and mammals. The usual outcome of infection is the formation of a benign outgrowth of cells, a wart or papilloma. These may occur almost anywhere in or on the body. Skin warts are divided into flat warts (superficial) and plantar warts (deeper). Genital warts (condylomas) occur in the genital tract and are transmitted by sexual intercourse.
• Warts can be treated by topical application of caustic substances or freezing, but surgical removal is more reliable, and is required for internal warts e.g. laryngeal. Warts may persist for many years, but may regress spontaneously due to a CTL response. There may be some enhanced risk of skin warts exposed to U.V. light developing into invasive squamous cell carcinoma .