Download Description of West Nile Virus

Tests to Diagnosis
Laboratory diagnosis is generally testing
of serum or cerebrospinal fluid to detect
virus specific IgM and neutralizing
antibodies. Four FDA cleared WNV IgM
ELISA kits available. (CDC, 2012)
Treatment Options
Mild Symptoms: Patient controls with
assistance from doctor.
Severe Symptoms: Hospital supportive
treatment: Intravenous fluids, breathing
care, nursing care.
(CDC, 2012)
Encephalitis acquired from an insect
borne virus doesn’t respond to antiviral
medications normally given for
encephalitis i.e., Acyclovir and
Ganciclovir. Therefore …
Corticosteroids are given for
inflammation of the brain.
Pheytoin is given to stop and prevent
seizures.
(Mayo Clinic Staff, 2011)
References
Bauman, R. (2010) Microbiology with Diseases by
Taxonomy: Third Edition. New York: Benjamin
Cummings.
Centers for Disease Control. 2012. West Nile Virus.
Retrieved August 04, 2012, from
http://www.cdc.gov/ncidod/dvbid/westnile/index.ht
m
CDC: Morbidity and Mortality Weekly Report
(MMWR). 2012. West Nile Virus Disease and Other
Arboviral Diseases — United States, 2011.
Retrieved August 04, 2012, from
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm
6127a3.htm
EncephalitisSymptoms.net. 2012. Encephalitis
Symptoms. Retrieved from
http://encephalitissymptoms.net/
Mayo Clinic Staff. 2011. Encephalitis. Retrieved
August 04, 2012 from
http://www.mayoclinic.com/health/encephalitis/DS
00226/
Night Owl Urgent Care. 2012. [I.V. Therapy]
Retrieved from
http://www.niteowlurgentcare.com/CommonQues
tions/DehydrationandIVFluidReplacement.aspx
Science Photo Library. [n.d.] West Nile viruses.
Coloured transmission electron micrograph (TEM).
Retrieved from
http://www.sciencephoto.com/media/87493/enlarge
(CDC, 2012)
Wikipedia. (2012). West Nile virus. Retrieved
August 04, 2012, from
http://en.wikipedia.org/wiki/West_Nile_virus
West Nile Virus
Provided for Awareness Purposes by
Jill K. Glanz, Prevention is Key
www.preventioniskey.net
(Night Owl Urgent Care, 2012)
Description of West Nile Virus
Group: IV (+) ssRNA.
Between 11,000 and 12,000 nucleotides long.
Family: Flaviviridae.
RNA strand held within nucleocapsid.
Genus: Flavivirus.
Capsid contained within host-derived membrane.
Species: West Nile virus.
Relatively smooth protein surface.
(Wikipedia, 2012)
West Nile Virus, TEM
(Science Photo Library, n.d.)
Morbidity & Mortality Rates
In 2011, 712 cases of West Nile Virus were
reported in the U.S.
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226 (32%) nonneuroinvasive
486 (68%) neuroinvasive
273 (56%) neuroinvasive patients had
Encephalitis
547 (77%) hospitalized
43 (6%) died
Median age of patients who died: 74
Age range of those infected: 32 – 96
(CDC: MMWR, 2012)
Diseases Caused
West Nile Virus (WNV) is a potentially
serious illness, most commonly spread by
the bite of an infected mosquito.
Mosquitos acquire the WNV infection by feeding on
infected birds; they then transmit the infection to
humans and other animals through their bite.
A seasonal epidemic in nearly all fifty states of North
America, WNV starts in the summer and continues
into the fall.
(CDC, 2012)
(Encephalitissymptoms.net, 2012)
Severe Symptoms:
In approximately 1 of 750 people, West Nile Virus
invades the nervous system causing Encephalitis –
this can be fatal.
(Baumann, 2010)
Encephalitis is inflammation of the brain, most
commonly caused by viral infections.
(Mayo Clinic Staff, 2011)
Severe Symptoms include:
- high fever
- stiff neck
No Symptoms:
- disorientation
80% of infected people have no symptoms.
- muscle weakness
Mild Symptoms:
Neurological effects may be permanent.
20% of infected people develop:
Individuals over age 50 are more likely to develop
severe illness from the West Nile Virus infection.
- fever
- headache
- fatigue
- body aches
(CDC, 2012)
(CDC, 2012)
- headache
- coma
-tremors
- convulsions
- paralysis