Unlocking secrets of some of the world’s smallest viruses

A typical flu virus is so small that a thousand of them could fit in the width of a human hair. For decades, scientists have known about the existence of viruses many times smaller than that, called microviruses. Traces of these most miniscule of microbes were seen in the environment and in genetic sequences of bacteria, which microviruses use as hosts, but scientists had rarely been able to directly observe them until recently. Once they got a good look, researchers at The University of Texas at Austin were surprised to see how many tricks these petite pathogens could pack into a single strand of DNA in a package a quarter the size of an average flu virus. The findings are outlined in a new paper out this week in the journal PNAS and could have implications for future virus research and even potential medical applications. As hard as microviruses were to isolate,...