Background
Only two cases of papillomavirus infections in North American porcupines (Erethizon dorsatum) have been described thus far, and molecular investigation linked these cases to two distinct papillomavirus species.
Methods
In this report, we present the clinical, histological and molecular investigation of a third case of a porcupine papillomavirus infection. Papillomatous lesions occurred on the upper and lower lip of an otherwise healthy three-year old female that was kept in captivity. Within one month, the lesions progressed into exophytic black nodules, followed by a temporary stabilization and ultimately spontaneous regression within seven months of their initial observation. PCR-based screening using specific primers for Erethizon dorsatum papillomavirus 1 and 2 revealed the presence of both these virus types, after which nanopore sequencing was used to determine the complete sequences of the two virus genomes.
Results
One of the genomes shares 99.9% similarity with the only known sequence for Erethizon dorsatum papillomavirus 1, while the second represents a distinct lineage of Erethizon dorsatum papillomavirus 2, sharing only 93.3% similarity with the previously discovered strain.
Conclusions
This report marks the first observation of a papillomavirus co-infection in a North American porcupine, although the individual contribution of the two virus types to the clinical presentation was not assessed.