By Maria Raquel Kronen

Yellow Fever
Japanese Encephalitis
St. Louis Encephalitis
West Nile Virus
Hepatitis C
Hepatitis G

Wednesday March 12, 2008




Important dates in the history of the Flavi family.

Click here to see the Timeline

Sept 1999 - WNV NY Outbreak
Outbreak of West Nile virus occurs in New York, USA. 17 cases are confirmed, 20 human cases are suspected. 7 human deaths occur and many birds die. Virus is isolated from crows and more than 20 avian species in the New York and surrounding areas.

1984 - Birth of Flaviviridae
Flaviviridae family is separated from Togaviridae family due to strong differences in morphogenesis, biochemistry, and replication strategies. *note - Flaviviruses were initially misclassified as a member of the family Togaviridae due to superficial resemblances

1952 - DENV Serotypes Discovery
The existence of Dengue Virus serotypes 1 and 2 is established by HI tests and cross-protection studies in human volunteers by Sabin. Dengue serotypes 3 and 4 were not discovered until an epidemic occurred in the Philippines in 1956.

1951 - WNV Outbreaks
First recorded epidemics of West Nile Virus occur in Israel, 1951 through 1954. A subsequent outbreak occurs in 1957.

1951 - YFV Vaccine
Theiler and Smith discover a vaccine against Yellow Fever that is so efficacious it is still used today. They developed the vaccine by passing the Asibi strain in chick embryo tissue. Theiler receive the only Nobel Prize to ever be awarded for a viral vaccine in 1951.

1951 - MVEV Isolated
The first case of Murray Valley Encephalitis Virus is isolated from humans who died of the disease in the Murray Valley of Victoria and South Australia.

1943 - DENV Isolated
Dengue Virus is first isolated in mice by Kimura and Hotta in 1943. It is isolated in mice by Sabin and Schlesinger in 1944.

1938 - JEV Transmission
Mitamura, et al, report isolation of Japanese Encephalitis virus from the mosquito Culex tritaeniorhynchus.

1937 - WNV - Isolated
West Nile Virus is first isolated in a patient with a viral syndrome in the West Nile region of Uganda.

1935 - JEV Nakayama strain
The prototype Nakayama strain is recovered from a human brain in Tokyo.

1934 - JEV Isolated
Japanese Encephalitis is first isolated and reproduced by Hayashi via intercerebral inoculation of monkeys. The virus is named "Japanese Encephalitis B virus" to indicate its association with "B" also known as "summertime" encephalitis in Japan.

1932 - YFV Cultivated
Yellow Fever Virus is first cultivated in vitro.

1931 - Multiple Isolations
Viruses responsible for Louping ill, Saint Louis encephalitis, Japanese ence[halitis, West Nile fever, and Tickborne encephalitis all isolated. All of these viruses are neurotrophic and transmitted by arthropods, but are believed at time to be unrelated.

1927 - YFV Isolated
Yellow Fever Virus is first isolated by Mahaffy and Bauer via inoculation of Rhesus monkey with blood of infected patient in Ghana. This was the source of the Asibi strain, which was the parent of the 17D vaccine later discovered by Theiler and Smith.

1924 - JEV Outbreak
Severe outbreak of Japanese Encephalitis occurs in Japan. Filterable agent (containing JEV) is extracted from brain of infected human and passed to rabbits at this time.

1916 - MVEV Recognised
Murray Valley Encephalitis Virus is first recognized in Australia. Known primarily as Australian X disease, the virus was renamed in 1974, when the last major outbreak occurred. *note- if you click the following link, you have to actually click the link on the redirect page to be correctly redirected, otherwise the Australian site won't work (I think their site is under construction)*

1915 - YFV Rockefeller Foundation Program
The Rockefeller Foundation establishes a global program to study and attempt to control outbreaks of Yellow Fever.

1906 - DENV Transmission
Dengue Fever Virus is shown to be a filterable agent transmitted by mosquitoes. Transmission by Ae. aegypti (see image) was first described by Bancroft in 1906, then confirmed by Cleland in 1918. In 1907, Asburn and Craig found a filterable agent, infectious agent in human blood.

1900 - Walter Reed Discovery
Sir Walter Reed (1851-1902) discovers the first virus when he conclusively demonstrates that yellow-fever is transmitted by the bite of the mosquito Aëdes aegypti. Sir Walter experimentally transfers the disease via filtered serum of one infected individual to another healthy individual. As a result of Reed's findings, the American sanitationist, William Crawford Gorgas, is then able virtually to eliminate the disease from Havana, Cuba, within three months by exterminating mosquitoes in the area. Since then, incidence of yellow fever has been drastically reduced globally by application of this discovery.

1881 - YFV Hypothsis
Doctor Carlos J. Finlay, a Cuban physician, proposes the idea that the disease is spread by mosquitoes. However, the hypothesis is ridiculed and not excepted.

1871 - JEV Recognition
Disease resembling Japanese Encephalitis virus, with its characteristic meningoencephilitis, is clinically described in Japan to be present in both humans and horses.

1807 - LIV Discovery
Louping ill virus - a disease of sheep - is recognized in Scotland

1793 - YFV Philadelphia
Body: Massive outbreak of Yellow Fever occurs in Philadelphia, which at the time is the nation's capital. Kills 50,000, including Dolly Madison's first husband. Outbreak originally believed to have been imported from Haiti. Doctor Benjamin Rush, one of the original signers of the Declaration of Independence, believes at time disease is spread by decaying vegetable matter and that bleeding is therapeutic for disease treatment.

1684 - YFV Recognised
Yellow Fever first recognized in Yucatan, Mexico (although disease may have been present in Caribbean as early as 1498).


Bless you! Take care of that viral infection!