Flaviviruses yellow fever, dengue, west nile

reservoir of each flavivirus

yellow fever: primates

dengue: humans

west nile virus: birds

yellow fever

endemic to south america and africa

cases of yellow fever, why reemerging?

increased in past two decades due to poor vaccination coverage, forged immunization cards, counterfeit vaccines, climate change

yellow fever transmission

3-6 day incubation, jaundice and destroys liver, headaches and hemorrhages DEATH

how mosquitos transmit

transovarial: larva are birthed with the disease, does not need infected host. infected howl monkeys in the new world

Cuba and America war 1898

Major Walter Reed, military physician who studied microbiology sent to oversee health of US soldiers in Cuba

Carlos Juan Finlay

US trained physician to first propose mosquitos being the vectors for yellow fever in 1881. jesse lazear tested that theory

william crawford gorgas

helped eliminate yellow fever through the control of aedes mosquitoes

sylvatic yellow fever

when monkeys in the jungle infected by mosquitos pass to humans

intermediate yellow fever

semi domestic mosquitos come into contact with humans

urban yellow fever

when virus is transmitted human to human without other primates

Dr. Max Thieler Peeler

isolated the virus in 1930’s from Ghana patient to create live attenuated virus

DENGUE transmission

spread in 15th and 19th century due to globalization and slave trade. Currently a leading cause of death in tropical regions

Dengue symptoms

fever headache rash joint ache. dengue infection w/ serotype will give you immunity to that one, only one is lifelong. getting two serotypes worsens conditions

dengvaxia

9-16 y/o can now use who have previously contracted

Dengue

400 million cases, wild monkeys can be reservoir, spread by mosquito vector

West Nile Virus

First in Uganda in 1937, US in 1999 from exotic birds in Bronx zoo

WNV Symptoms

nausea, muscle weakness, swollen lymph nodes, encephalitis or meningitis sometimes

WNV THREE OUTCOMES

asymptomatic (4 out of 5), west nile virus (mild febrile syndrome), invades the nervous system