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The early phase (1915-1955)

In 1915, Frederick W. Twort discovered the phenomenon of transformation while working with the variants of vaccinia viruses, simultaneously Felix d'Herelle discovered bacteriophage and developed the assay to titrate the viruses by plaques. Wendell Stanley (1935) first crystallized the TMV and the first electron micrograph of the tobacco mosaic virus (TMV) was taken in 1939. In 1933 Shope described the first papillomavirus in rabbits. The vaccine against yellow fever was made in 1938 by Thieler and after 45 years of its discovery, polio virus vaccine was made by Salk in 1954.

The modern phase (1960-present)

During this phase scientists began to use viruses to understand the basic question of biology. The superhelical nature of polyoma virus DNA was first described by Weil and Vinograd while Dulbecco and Vogt showed its closed circular nature in 1963. In the same year Blumberg discovered the hepatitis B virus. Temin and Baltimore discovered the retroviral reverse transcriptase in 1970 while the first human immunodeficiency virus (HIV) was reported in 1983 by Gallo and Montagnier . The phenomenon of RNA splicing was discovered in Adenoviruses by Roberts , Sharp , Chow and Broker . In the year 2005 the complete genome sequence of 1918 influenza virus was done and in the same year hepatitis C virus was successfully propagated into the tissue culture.

Many discoveries are done using viruses as a model. The transcription factor that binds to the promoter during the transcription was first discovered in SV40. The phenomenon of polyadenylation during the mRNA synthesis was first described in poxviruses while its presence was first reported in SV40. Many of our current understanding regarding the translational regulation has been studied in poliovirus. The oncogenes were first reported in Rous sarcoma virus. The p53, a tumor suppressor gene was first reported in SV40.