A novel pulmonary polyomavirus in alpacas (Vicugna pacos)

Viral metagenomic analysis detected a novel polyomavirus in a 6-month old female alpaca (Vicugna pacos) euthanized after a diagnosis of disseminated lymphosarcoma. The viral genome was fully sequenced, found to be similar to other polyomaviruses in gene architecture and provisionally named Alpaca polyomavirus or AIPyV. Viral nucleic acid was detected by PCR in venous blood, spleen, thymus, and lung. AIPyV phylogenetically clustered in the "Wuki" group of PyVs, which includes WU and MI polyomaviruses, commonly found in human respiratory samples. In an ISH analysis of 17 alpaca necropsies, 7 had detectable virus within the lung. In animals without pneumonia, probe hybridization was restricted to the nuclei of scattered individual bronchiolar epithelial cells. Three of the ISH positive alpacas had interstitial pneumonia of unknown origin, and in these animals there was viral nucleic acid detected in bronchiolar epithelium, type II pneumocytes, and alveolar macrophages. The pattern of AIPyV distribution is consistent with a persistent respiratory virus that has a possible role in respiratory disease. (C) 2017 Elsevier B.V. All rights reserved.