Multiple etiological agents associated with the deaths of trafficked pangolins

As the world’s most trafficked mammal, the trafficked pangolins, from which multiple microorganisms are identified, may be more prone to diseases by various zoonotic agents and also accelerate their spread. Herein, we collected internal organ and/or fecal samples from 15 trafficked pangolins rescued at the Jinhua Wildlife Rescue Station in Zhejiang province of China. Through meta-transcriptomics and PCR, pestivirus, canine parvovirus 2 (CPV-2), human parainfluenza virus 2 (HPIV2) and Pseudomonas aeruginosa at high abundances were identified in three dead pangolins, while no potential pathogens were found in the remaining 12 alive pangolins. Of three dead pangolins, Pujiang-Pangolin-2 and Pujiang-Pangolin-3 were co-infected by four and two agents respectively, which led to more pronounced pathological changes in them than in Qingtian-Pangolin-1, from which only CPV-2 was detected. In particular, Pujiang-Pangolin-2 had an extremely high abundance of CPV-2 and P. aeruginosa in lung and spleen, and also exhibited severe pathologic changes, while Pujiang-Pangolin-3 had a higher abundance of pestivirus and exhibited more severe hemorrhage in its internal organs. Notably, the viral agents identified herein were more closely related to the pestiviruses harbored by Manis javanica, CPV-2 sampled from dogs in Vietnam, and HPIV2 sampled from humans in Netherlands, respectively, while P. aeruginosa showed a closer evolutionary relationship to the bacteria sampled from humans in and outside of China. In sum, combing with previous studies, these data suggest that the trafficked pangolins are prone to various infections and also resulted in the spread of zoonotic agents.