The urgent mystery of where viruses hide

Everything comes from somewhere. Dangerous new viruses typically come from animals.Human influenza viruses? Those come from wild aquatic birds. Hantaviruses come from rodents. Mpox virus also comes from rodents, including squirrels, which is one reason it’s no longer called monkeypox virus. The pandemic-causing form of HIV came from chimpanzees.There are reasons for this pattern. Viruses can replicate only in the cells of cellular creatures (animals, plants, fungi, microbes), and because we humans are animals ourselves, animal viruses most readily adapt to infect us. This connection is worth remembering as we deal with the continuous onslaught of newly emerging and reemerging viruses.