The English word "virus" comes from the Latin vīrus, which refers to poison and other noxious liquids. Vīrus comes from the same Indo-European root as Sanskrit viṣa, Avestan vīša, and Ancient Greek ἰός (iós), which all mean "pois… See more

Viruses are found wherever there is life and have probably existed since living cells first evolved. The origin of viruses is unclear because they do not form fossils, so molecular techniques are used to infer how they arose… See more

The first evidence of the existence of viruses came from experiments with filters that had pores small enough to retain bacteria. In 1892, Dmitri Ivanovsky used one of these filters to show that sap from a diseased to… See more