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Introduction to Viruses

Author(s): Christine Herrmann, PhD

How Were Viruses First Discovered? 2

In the same year that Beijerinck discovered the tobacco mosaic agent, the German scientists, Friedrich Loeffler and Paul Frosch, observed that the agent which causes foot-and-mouth illness in livestock also was small enough to pass through a filter and required the host organism to reproduce. The first human virus, the agent that causes yellow fever, was discovered in 1901 by a team of researchers led by Walter Reed. Dr. Reed’s team was sent to Cuba to control an outbreak of yellow fever that occurred during the Spanish-American War.

Bacterial viruses (viruses that infect bacterial cells) were first described in the early 1900s and were named bacteriophages. Many other viruses have since been discovered. Identification of agents that cause disease sometimes is difficult because of the dangers involved in working with infectious agents. In addition, researchers must find a suitable host in which to grow and study certain viruses, but new technologies are facilitating this work.

Funded by the following grant(s)

Video and transcript courtesy of Wah Chiu, PhD, National Center for Macromolecular Imaging at Baylor College of Medicine. Funding for the video provided by NCMI, NIH.