Editing West Nile fever (section)

===Risk factors===
Risk factors independently associated with developing a clinical infection with WNV include infants, having a [[immunodeficiency|weak immune system]], and a patient history of organ transplantation.<ref name=Jong.71>{{cite book |first1=Nicole|last1=Lindsey|first2=Emily|last2=McDonald|first3=Marc|last3=Fischer|first4=J. Erin|last4=Staples|editor1-last=Jong |editor1-first=Elaine C. |editor2-last=Stevens |editor2-first=Dennis L. |title=Netter's Infectious Diseases |date=2022 |publisher=Elsevier |location=Philadelphia |isbn=978-0-323-71159-3 |pages=422–427|edition=2nd |chapter-url=https://books.google.com/books?id=l8skEAAAQBAJ&pg=PA422|language=en |chapter=71. West Nile virus Disease}}</ref><ref>{{cite journal  |vauthors=Kumar D, Drebot MA, Wong SJ, etal |title=A seroprevalence study of West Nile virus infection in solid organ transplant recipients |journal=Am. J. Transplant. |volume=4|issue=11 |pages=1883–8 |year=2004 |pmid=15476490 |doi=10.1111/j.1600-6143.2004.00592.x |s2cid=31695008 |doi-access= }}</ref>   For neuroinvasive disease the additional risk factors include older age (>50+), male sex, [[hypertension]], and [[diabetes mellitus]].<ref>{{cite journal |vauthors=Jean CM, Honarmand S, Louie JK, Glaser CA |title=Risk factors for West Nile virus neuroinvasive disease, California, 2005 |journal=Emerging Infect. Dis. |volume=13 |issue=12 |pages=1918–20 |date=December 2007 |pmid=18258047 |pmc=2876738 |doi=10.3201/eid1312.061265 }}</ref><ref>{{cite journal  |vauthors=Kumar D, Drebot MA, Wong SJ, etal |title=A seroprevalence study of west nile virus infection in solid organ transplant recipients |journal=Am. J. Transplant. |volume=4|issue=11 |pages=1883–8 |year=2004 |pmid=15476490 |doi=10.1111/j.1600-6143.2004.00592.x |s2cid=31695008 |doi-access= }}</ref>

A genetic factor also appears to increase susceptibility to West Nile disease. A mutation of the gene ''[[CCR5]]'' gives some protection against [[HIV]] but leads to more serious complications of WNV infection. Carriers of two mutated copies of ''CCR5'' made up 4.0 to 4.5% of a sample of people with West Nile disease, while the incidence of the gene in the general population is only 1.0%.<ref>{{cite journal | first = WG | last = Glass |author2=Lim JK |author3=Cholera R |author4=Pletnev AG |author5=Gao JL |author6=Murphy PM  | date = October 17, 2005 | title = Chemokine receptor CCR5 promotes leukocyte trafficking to the brain and survival in West Nile virus infection | journal = Journal of Experimental Medicine | volume = 202 | issue = 8 | pages = 1087–98 | pmid = 16230476 | doi = 10.1084/jem.20042530 | pmc = 2213214}}</ref><ref>{{cite journal | first = WG | last = Glass |author2=McDermott DH |author3=Lim JK |author4=Lekhong S |author5=Yu SF |author6=Frank WA |author7=Pape J |author8=Cheshier RC |author9=Murphy PM   | date = January 23, 2006 | title = CCR5 deficiency increases risk of symptomatic West Nile virus infection | journal = Journal of Experimental Medicine | volume = 203 | issue = 1 | pages = 35–40 | pmid = 16418398 | doi = 10.1084/jem.20051970 | pmc = 2118086}}</ref>

The most at risk occupations in the U.S. are outdoor workers, for example farmers, loggers, landscapers/groundskeepers, construction workers, painters, summer camp workers and pavers.<ref>{{Cite web|url=https://www.osha.gov/dts/shib/shib082903b.html|title=Safety and Health Information Bulletins {{!}} Workplace Precautions Against West Nile Virus {{!}} Occupational Safety and Health Administration|website=www.osha.gov|language=en-us|access-date=2018-11-28}}</ref> Two reports of accidental exposure by laboratory personnel working with infected fluids or tissues have been received. While this appears to be a rare occurrence, it highlights the need for proper handling of infected materials. The [[World Health Organization]] states that there are no known cases of health care workers acquiring the virus from infected patients when the appropriate infection control precautions are observed.<ref>{{Cite web|url=https://www.who.int/news-room/fact-sheets/detail/west-nile-virus|title=West Nile virus|website=World Health Organization|language=en-US|access-date=2018-11-28}}</ref>