• Discovery of Viruses
• Introduction to Viruses
• Structure of Viruses
• Classification of Viruses
• Viral Disease
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- The word "virus" comes from Latin and means slimy liquid or poison. In 1984, a scientist named Charles Chamberland, who worked with Louis Pasteur, invented a special filter made of porcelain called the Chamberland-Pasteur filter. This filter had very tiny pores, measuring 0.1 micrometers, which were small enough to remove all bacteria measuring 0.2 micrometers or larger from any liquid that passed through it.
- Later, in 1892, Dmitri Ivanovslcy used the Chamberland filter to study an extract from infected tobacco plant leaves. Even after removing the bacteria from the filtrate, Ivanovslcy found that it still caused disease in plants. He concluded that there must be an infectious component smaller than a bacterium causing the tobacco mosaic disease (TMD).
- In 1899, another scientist named Martinus Beijerinck continued the investigation and described the pathogenic agent responsible for TMD as a "contagious living fluid." These filterable agents were later named viruses.
- In 1935, M. Stanley successfully crystallized the infectious particle known as the tobacco mosaic virus (TMV). The invention of the electron microscope allowed scientists to discover many more viruses, which are now studied in the field of virology.
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