Diverse and Highly Recombinant Anelloviruses Associated with Weddell Seals in Antarctica

The viruses circulating among Antarctic wildlife remain largely unknown. In an effort to identify viruses associated withWeddell seals (Leptonychotes weddellii) inhabiting the Ross Sea, vaginal and nasal swabs, and faecal samples were collectedbetween November 2014 and February 2015. In addition, a Weddell seal kidney and South Polar skua (Stercorariusmaccormicki) faeces were opportunistically sampled. Using high throughput sequencing, we identified and recovered 152anellovirus genomes that share 63–70% genome-wide identities with other pinniped anelloviruses. Genome-wide pairwisecomparisons coupled with phylogenetic analysis revealed two novel anellovirus species, tentatively named torque tenoLeptonychotes weddellii virus (TTLwV) -1 and -2. TTLwV-1 (n¼133, genomes encompassing 40 genotypes) is highly recom-binant, whereas TTLwV-2 (n¼19, genomes encompassing three genotypes) is relatively less recombinant. This study documents ubiquitous TTLwVs among Weddell seals in Antarctica with frequent co-infection by multiple genotypes, how-ever, the role these anelloviruses play in seal health remains unknown.