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West Nile VirusMiyuki Horie, MPH student
Walden UniversityPUBH 6165-3
Dr. Howard RubinWinter Qrt., 2012/13
Introduction
First West Nile virus cases in the world … Uganda, 1937
West Nile virus in the US … New York, 1999 Continue to re-emerge every year during the
summer Worst outbreaks in the US record … 2012
o Involved 48 stateso Killed 89 peopleo 1 death in Washington, DC
Objectives Know about West Nile virus (WNV) infection
o Route of Transmissiono Vectorso Clinical Symptomso People at Risko Treatment
Preventiono Around Youo Around Homestead
Where to contacto If contracted WNVo For additional Information
West Nile VirusFacts
Arthropod-borne virus = Arbovirus
Transmitted by mosquitos Can infect people, birds,
horses, and other mammals
Causes mild-flu like symptoms or sever symptoms in some
Seasonal epidemic between Summer –Fall(CDC, 2012c; DOH, 2012b; Winn et al., 2006)
WNVRoute of Transmission
Primary Transmission Cycle = Birds Mosquitos Incidental Transmission = Mosquitos Human, Horses
o Birds = Reservoiro Mosquitos = Vector o Human, Horses = Incidental host/Dead-end
(CDC, 2012a; DOH, n.d.; Huhn et al., 2003; Winn et al., 2006)
WNVBirds / Reservoir
Primary host/reservoir of West Nile virus
200+ species affected Infected birds become ill,
die, or survive with permanent immunity
Develops infectious viremia for 1-4 days
Migrant birds “ferry” WNV(CDC, 2012a; DHMH, 2013; Rappole, Derrickson, &
Hubálek, 2000; Winn et al., 2006)
WNVMosquitos / Vector
Life cycleEggs (in swamp/standing water) Larvae (in water) Pupae Adult
Maleso Live up to 7-10 dayso Feed on plant juice
Femaleso Live 30+ dayso Feed on animal bloodo Become infected with WNV when
feed on infected birdso Transmit WNV when feed on other
animal(CDC, 2012a; DOH, n.d.; EPA, 2012b; EPA, 2012c)
male female
WNVMosquitoes /Vector
Culex mosquito Asian Tiger mosquito
(cdc, 2005; DOH, n.d.)
• “Common house mosquito” in North America
• Yellow body + brown stripes on abdomen
• Feed on birds, other mammals• Active at dusk and down• Attracted by swampy/stagnant
water
• Originally from Asia• Large size• Black & white stripes on legs
and abdomen• Feed on mammals• Active all day• Attracted by CO2, humidity
WNVClinical Significance
No symptoms – 80% Mild symptoms – 20%
o Full-like symptomso Fevero Headacheo Body acheo Nauseao Skin rashes (torso)
Sever symptoms – Approx. 1 in 150 caseso “Neuroinvase WNV”: Encephalitis, Meningitis
• Disorientation, Comma, Convulsion, Tremors, Numbness, Paralysiso High fevero Headache + Neck stiffness o Death (3-15%)
(CDC, 2012c; Huhn et al., 2003; Salinas & Steiner, 2012)
WNVWho’s at Risk?
People who are risk are:o 0ver 50 years oldo Immunocompromisedo Working/spending many
hours outside Pregnant or nursing
women do NOT have increased risk for WNVo Only 1 case of mother-
fetus transmissiono No report/data on WNV
infection through Breastfeeding
(CDC, 2012b; CDC, 2012c; Huhn et al., 2003)
She’s Okay!
WNVTreatment
No specific treatment for WNV Self-limiting – Mild symptoms last only a few days No/Rare chronic case – person infected with WNV most
likely to acquire immunity Sever cases (Neuroinvasive WNV) should seek
medical attentiono Hospitalizationo Supportive care: IV fluids, Respiratory supporto Secondary prevention to reduce morbidityo Notification to Department of Health (DOH)(CDC, 2012b; DOH, 2012b)
WNVPrevention
No WNV Vaccine Primary prevention =
Avoid mosquito bite Use mosquito repellant
(e.g. DEET) when outside
Wear long-sleeve clothes Apply permethrin on to
the clothes Stay inside during the
mosquito-feeding hours (at dusk & dawn)
(CDC, 2012b; DOH, 2012a; EPA, 2012b)
ANTI
M
OSQU
ITO
(F51
06)
WNVMosquito Repellant
2 types of mosquito repellant recommended are… DEET (N, N-dimethyl-m-toluamide)
o Most effective & Widely availableo Directly apply onto the skino Select appropriate % for your need
• <30% DEET for children• 23.8% DEET… 5-hr protection• 6.65% DEET… 2-hr protection• 4% DEET… ~90-min protection
Permethrino Apply onto clothes for additional
protectiono No health concerns at low level(CDC, 2005; DOH, 2012a; DOH, 2012b; EPA, 2012a; FDACS, 2012)
WNVControl
“West Nile virus program”o Reduce mosquito-breeding sites in all 8 Wards in DC
• Dispose of old tires, cans and bottles and other containers• Clean roof gutters• Clear garbage area – Close the lid• Place tarp over grills, firewood piles, tires, boats• Turn over wading pools • Clean & Chlorinate swimming pools
Notify DOH for suspected West Nile virus outbreaks – Clinicians(DOH, 2005; DOH, n.d.)
WNVFor Your Information
For Mosquito control…
If you find a dying bird…o Contact
If you find a dead bird… o Do not touch it by bare hand o Report to
o For pick-up of dead animal… For any questions/concerns about WNV…
Animal Disease Control Program
Phone: (202) 535-2323DC Animal ShelterPhone: (202) 576-
6664West Nile Virus Call
CenterPhone: (202) 535-2323
Call #311
Department of HealthPhone: (877) 672-2174
Office Hours: M - F 8:15 am – 4:45 pm www.doh.dc.gov
WNVReview
Mosquito-borne disease Birds are the primary host of WNV Mosquitos are the vector of WNV
o become infected through infected birds through biteo transmit the infection to humans through bite
Usually mild, flu-like symptoms for a few days Neuroinvasive WNV is rate and sever condition People older than 50 years are at higher risk!! Primary prevention for WNV is use of Mosquito
repellant! Control of WNV is clearing mosquito’s breeding site! Contact DOH @(877) 672-2174 for questions &
Concerns
References Centers for Disease Control and Prevention. (2005). What you need to know about mosquito
repellant. Retrieved January 14, 2013,from CDC website: http://www.cdc.gov/ncidod/dvbid/westnile/mosquitorepellent.htm
Centers for Disease Control and Prevention. (2012a). Fight the bite! Retrieved January 14, 2013, from CDC website: http://www.cdc.gov/ncidod/dvbid/westnile/index.htm
Centers for Disease Control and Prevention. (2012b). West Nile virus: Epidemiologic information for clinicians. Retrieved January 14, 2013,from CDC website: http://www.cdc.gov/ncidod/dvbid/westnile/clinicians/epi.htm
Centers for Disease Control and Prevention. (2012c). West Nile virus: What you need to know. Retrieved from http://www.cdc.gov/ncidod/dvbid/westnile/wnv_factSheet.htm
Department of Health. (2012a). Controlling and repelling mosquitoes. Retrieved January 14, 2013, from DOH website: http://doh.dc.gov/node/164922
Department of Health. (2012b). West Nile virus. Retrieved January 14, 2013, from DOH website: http://doh.dc.gov/service/west-nile-virus
Department of Health. (n.d.). West Nile virus brochure [pdf format]. Retrieved January 14, 2013, from DOH website: http://doh.dc.gov/sites/default/files/dc/sites/doh/publication/attachments/West-Nile-Virus-Brochure.pdf
References Department of Health and Mental Hygiene. (2013). West Nile virus. Retrieved January 19, 2013,
from DHMH website: http://ideha.dhmh.maryland.gov/oideor/czvbd/sitepages/west-nile.aspx#
Florida Department of Agriculture & Consumer Services. (2012). Frequently asked questions about permethrin [pdf format]. Retrieved January 19, 2013, from http://www.flaes.org/pdf/Permethrin%20QA%20final%208-25-11.pdf
Howell, T. Jr. (August, 2012). D.C. resident contracts West Nile virus. Times. Retrieved January 14, 2013 from http://www.washingtontimes.com/news/2012/aug/22/dc-resident-contracts-west-nile-virus/
Huhn, G. D., Sejvar, J., Montgomery, S. P., & Dwokin, M. S. (2003). West Nile virus in the United States: An update on an emerging infectious disease. American Family Physician, 68(4), 653-661. Retrieved from AAFP website: http://www.aafp.org/afp/2003/0815/p653.html
Medical News Today. (2012, September). West Nile virus, Worst year ever says CDC, USA. Retrieved January 19, 2013, from MNT website: http://www.medicalnewstoday.com/articles/249974.php
National Center for Biotechnology Information, U.S. National Library of Medicine. (2012). West Nile virus. Retrieved February 1, 2013 from PubMed Health website: http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004457/
References Rappole, J. H., Derrickson, S. R., & Hubálek, Z. (2000, August). Migratory birds and spread
of West Nile virus in the Western Hemisphere. Emerging Infectious Disease, 6(4). Retrieved from CDC website: http://wwwnc.cdc.gov/eid/article/6/4/00-0401_article.htm
Salinas, J.D., & Steiner, M.L. (2012). West Nile virus. Retrieved January 19, 2013, from Medscape Reference website: http://emedicine.medscape.com/article/312210-overview
Ticinfo.com. (2000). Permethrin repellant. Retrieved January 19, 2013, from http://www.tickinfo.com/permethrin.htm
U.S. Environmental Protection Agency. (2012a). Alphabetical list of pesticide fact sheets. Retrieved January 14, 2013, from EPA website: http://www.epa.gov/pesticides/factsheets/alpha_fs.htm
U.S. Environmental Protection Agency. (2012b). Joint statement on mosquito control in the United States from the U.S. Environmental Protection Agency (EPA) and the U.S. Centers for Disease Control and Prevention (CDC). Retrieved January 19, 2013, from EPA website: http://www.epa.gov/pesticides/health/mosquitoes/mosquitojoint.htm
References U.S. Environmental Protection Agency. (2012d). The insect repellent DEET.
Retrieved January 14, 2013, from EPA website:http://www.epa.gov/pesticides/factsheets/chemicals/deet.htm
Washington Examiner. (2012, September). West Nile virus kills D.C. resident. Retrieved from: http://washingtonexaminer.com/west-nile-virus-kills-d.c.-resident/article/2507261#.UPvmR2_hrZI
Winn, W. C., Jr., Allen, S. D. A., Janda, W. M., Koneman, E. W., Procop, G. W., Schreckenberger, P. C., & Woods, G. L. (2006). Koneman’s color atlas and textbook of diagnostic microbiology (6th ed.). Philadelphia: Lippincott Williams & Wilkins.
Images Cited Bentley, T. (2007). Mosquito - Culex territans - Male [Photo]. Retrieved January 20,
2013, from Bugguide website: http://bugguide.net/node/view/141495 Eastern Idaho Public Health District. (n.d.) Fight the bite [Image]. Retrieved January
20, 2013, from EIPHD website: http://www.phd7.idaho.gov/Infectious%20Disease/WNV/wvnmain.html
Centers for Disease Control and Prevention. (2007). Number of West Nile virus neuroinvasive disease cases, by week of illness onset -- United States, 2007 [Figure]. Retrieved from Medscape website: http://www.medscape.com/viewarticle/577372
Centers for Disease Control and Prevention. (2012). West Nile virus (WNV) activity reported to ArboNET, by county, United States, 2012 (as of December 11,2012)[Figure]. Retrieved from CDC website: http://www.cdc.gov/ncidod/dvbid/westnile/Mapsactivity/surv&control12MapsAnybyCounty.htm
Clark, G. (n.d.). Shoo fly [Photo]. Retrieved January 20, 2013, from ScienceNewsforKIDS website: http://www.sciencenewsforkids.org/2008/06/bug-bug-go-away/
Images Cited Firstyle Products Ltd. (n.d.) Anti Mosquito (F5106) [Product photo]. Retrieved January
20, 2013, from http://www.made-in-china.com/showroom/firstyle/product-detailDqMxQeEJjGVn/China-Anti-Mosquito-F5106-.html
Gathany, J. (n.d.) Culex quinquefasciatus, a representative of the Culex genus of mosquitoes [Photo]. Retrieved January 20, 2013, from University of California, Riverside website: http://newsroom.ucr.edu/2434
Goldsmith, C. (n.d.). West Nile virus [Image]. Retrieved January 20, 2013, from News-Medical.Net website: http://www.news-medical.net/health/West-Nile-Virus.aspx
Kane Country Health Department. (n.d.). West Nile cycle [Figure]. Retrieved January 20, 2013, from: http://kanehealth.com/west_nile_info.htm
Klemm, D. (2003). Transmission cycle of West Nile virus [Figure]. Retrieved from AAFP website: http://www.aafp.org/afp/2003/0815/p653.html
TomMyersPhoto.com. (n.d.). 5 Asian Tiger mosquito 640 [Photo]. Retrieved January 20, 2013, from AllRite Pest Control website: http://www.allritepest.com/?publications=pr-management-3