Bovine papillomatosis in Sicily: virus identification, diagnosis and co-infections

Bovine papillomatosis is an infectious disease distributed worldwide among cattle herds consisting of hyper-proliferative lesions affecting cutaneous tissue and mucosa. The disease, known as papillomas, may occur in different part of the body. Bovine papillomaviruses (BPVs) are non-enveloped double stranded DNA viruses belonging to the Papillomaviridae family, a group of viruses that infect all amniotes. Despite the benign characters of the lesions, in some cases bovine papillomatosis may dramatically reduce the productive performances when the lesions are extensive over the body involving teats and udders.Aim - This work was particularly aimed at the identification and characterization of BPVs circulating in Sicily in order to obtain autovaccine against BPVs. Material and methods - Thirty-one epithelial lesions, collected from cattle, clinically diagnosed as papillomas, were referred to the Laboriatories of Istituto Zooprofilattico Sperimentale of Sicily. Samples were analyzed by electron microscopy, PCR amplification, Rolling Circle Amplification, sequencing, negative staining electronic microscopy and standard histological examinations.Results and discussion - The investigation revealed the presence of different BPV types 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, mostly in the form of co-infections. Besides BPV amplification, zoonotic viruses belonging to the genus parapoxvirus within the Poxviridae family were screened and detected in 11 samples. This is the first study performed in Sicily, reporting a wide diversity of BPV genera and types circulating in the territory.Conclusion - The data collected showed the necessity of proper diagnosis to produce an effective vaccine while virus characterization is important to know the epidemiological scenario of the region and set appropriate control measures and reliable diagnostic methods for bovine papillomatosis. The presence of co-infecting zoonotic viral agents underlies the need for a better understanding of the possible interactions between the two viruses and suggests the importance of identifying proper measures to prevent the infection to humans.