The original analog viral media is the virus. Spanish flu, smallpox, ebola, HIV. Throughout history they have co-evolved with humanity with often disastrous consequences. But viruses are not to be outdone by bacteria: cholera and plague have also reached pandemic status. Vaccines, antibiotics, and other medical advances have provided treatment, but the rapid and unpredictable mutation of these highly adaptable organisms makes perfect prevention nearly impossible. As we are now in the unfortunate midst of being reminded. But microfauna can also serve many useful purposes: the bacteria of our microbiome play a key role in our immune defenses against viruses while viruses themselves are deployed by scientists to target genetic interventions. In this issue we'll take a broad look at microbes and parasites, diseases and therapies.