How difficult would it be to study the virome of living whales? You might think that sampling would be the hard part, but not if you used a drone.
A drone was used to collect the breath (‘blow’) from 19 humpback whales near Sydney, Australia. The video below show how a sampling chamber carried by a drone was used for this process.
RNA was extracted from the collected samples and subjected to high-throughput sequencing. The results revealed a variety of both DNA and RNA virus sequences that can be placed into 42 known virus families, including 29 containing bacteriophages.
The most abundant eukaryotic virus sequences resembled those of Circoviridae, which are small, ubiquitous, single-stranded DNA containing viruses; the Parvoviridae (with linear, ssDNA genomes), and Tombusviridae (plant viruses with single stranded, positive sense RNA genomes). Other minor viruses include new members of the Picornaviridae and Astroviridae, both with plus strand RNA genomes.
It is difficult to know if these viruses actually infect humpback whales, or if they are simply passengers. For this reason, the authors call their sequences whale-associated.
I love the approach to sampling the whale virome using a drone. But eventually we will have to get up close and personal to determine if any of these sequences are from viruses that actually replicate in whales.