At https://phys.org/print442742348.html … the subject is viruses, the most abundant form of life on Earth. These are outliers in the search for life on other planets. Now, astrobiologists are being urged to do the research more thoroughly. The humble virus is integral to life on Earth – a disease causing agenb (but is it as simplistic as that?) Viruses are entities where genomes replicate themselves inside living cells. They can transfer from one cell to another. Viruses comprise the whole reproduction cycle – and use living cells to reproduce. Virions on the other hand are viral seeds that could become viruses if they happen upon a living cell to establish life as a virus. If virions are present on other planets this may indicate cellular life may once have existed there – or the planet has been seeded from space (perhaps). No mention is made of space seeding – in the press release.