Portal:Viruses/Calendar/April

1 April 1911: Peyton Rous showed that a cell-free isolate could transmit sarcoma in chickens, an early demonstration of cancer caused by a virus

7 April 1931: First electron micrograph taken by Ernst Ruska and Max Knoll

8 April 1976: Bacteriophage MS2 (pictured) sequenced by Walter Fiers and coworkers, first viral genome to be completely sequenced

8 April 1990: Death from AIDS of Ryan White, haemophiliac teenager for whom the Ryan White Care Act is named

8 April 1992: Tennis player Arthur Ashe announced that he had been infected with HIV from blood transfusions

9 April 1982: Stanley Prusiner proposed proteinaceous prions as the cause of scrapie

12 April 1955: Success of trial of Jonas Salk's polio vaccine announced

12 April 2013: New order of double-stranded DNA bacteriophages, Ligamenvirales, announced

15 April 1957: André Lwoff proposes a concise definition of a virus

21 April 1989: Discovery of hepatitis C virus by Qui-Lim Choo and colleagues

28 April 1932: First yellow fever vaccine announced at an American Societies for Experimental Biology meeting by Wilbur Sawyer

29 April 2015: PAHO and WHO declared the Americas region free from rubella transmission

30 April 1937: Discovery of Theiler's murine encephalomyelitis virus, later a model for multiple sclerosis research