West Nile Virus Flashcards
What is the leading cause of domestically acquired arboviral disease in the U.S?
West Nile Virus
What are predisposing factors of West Nile Virus?
1) Outdoor Activities during SPRING and SUMMER
2) Mosquito Bites
How is West Nile Virus transmitted?
1) Culex Mosquito
2) Blood Transfusion
3) Organ Donation
4) Mother to Child transmission
What mosquito is responsible for transmitting West Nile Virus?
Culex Mosquito
What is the incubation period for West Nile Virus?
2-6 days
Is West Nile Virus a reportable disease?
Yes
What type of West Nile Virus is lethal?
Neuroinvasive
When do West Nile Virus outbreaks typically occur?
Spring/Summer
Mid July to Early September
Why do elevated temperatures & rainfall correlate with increased WNV transmission & infection?
The warmer & hotter it is, the more mosquitos will breed
What are considerd “Dead End Hosts” with West Nile Virus?
Humans and Horses
Is a patient infected with west nile virus infectious to others aboard the ship?
Nah, Humans are Dead End Hosts
Mosquitoes become infected with west nile virus when they feed on ______________.
Infected Birds
When should west nile virus be considered?
In any febrile patient or acute neurologic illness with recent exposure to mosquitoes during the summer months in WNV endemic areas.
An acute systemic febrile illness that may be accompanied by:
1) Headache, weakness, myalgia, or arthralgia
2) Gastrointestinal symptoms
3) Transient (Come and Go) maculopapular rash
West Nile Virus
Neuroinvasive West Nile Virus typically manifests as ___________, ____________, or _____________.
1) WNV Meningitis
2) WNV Encephalitis
3) ANV Acute Flaccid Paralysis
What neuroinvasive manifestation of west nile virus presents with fever, headache, and nuchal rigidity.
WNV Meningitis
What neuroinvasive manifestation of west nile virus presents with fever and altered mental status, seizures, focal neurologic deficits, or movement disorders such as tremor or Parkinsonism.
WNV Encephalitis
What neuroinvasive manifestation of west nile virus presents with respiratory paralysis requiring mechanical ventilation, isolated limb paresis or paralysis and can occur without fever or apparent viral prodrome.
WNV Acute Flaccid Paralysis
How is West Nile Virus Diagnosed?
Identifying IgM antibodies in the serum or Cerebral Spinal Fluid with ELISA
Mumps, HSV, Poliovirus, Measles, and Pertussis are differential diagnoses for what infectious disease?
West Nile Virus
What is the first line management protocol for West Nile Virus?
Vigorous supportive measures:
1) Severe meningeal symptoms- Pain control, Antiemetics, and Rehydration
2) Encephalitis symptoms- Monitor for seizures due to increased inracranial pressure. Monitor Airway.
3) Poliomyelitis Symptoms- Monitor Airway
4) Ventilator support if respiratory failure
What is the disposition for West Nile Virus?
MEDEVAC if signs of encephalitis, meningitis, or paralysis.
What are the prevention methods for West Nile Virus?
1) Mosquito Control
2) Protective measures (Repellents, Long sleeve shirts and pants, limit outdoor exposure during the night)
3) Screening blood and organ donors
4) Air conditioning, window and door screens, reducing breeding sites
How long can the fatigue, malaise, and weakness be present for a patient with non-neuroinvasive West Nile Virus?
Weeks to Months
What type of Neuroinvasive West Nile Virus has the lowest fatality rate?
West Nile Virus Meningitis
What types of Neuroinvasive West Nile Virus may have residual neurologic deficits?
WNV Encephalitis
WNV Poliomyelitis
