August 9, 2013
What’s West Nile virus?
West Nile virus (WNV) is a probably severe sickness that’s carried from contaminated birds to people through mosquitoes. The virus first gained consideration within the U.S. in 1999 after an outbreak in New York Metropolis prompted 62 instances of encephalitis and 7 deaths. Since that point, the virus has unfold dramatically. WNV exercise has now been detected in all 48 continental states, the District of Columbia, and Puerto Rico.
Practically all human infections of WNV are attributable to mosquito bites, so, not surprisingly, in North America, human sickness from WNV peaks in late summer season and early fall. This seasonal variation is because of the truth that mosquitoes emerge within the spring in temperate climates and proceed to feed till they die out within the fall when temperatures drop. Nonetheless, sporadic instances of WNV happen all year long in southern states the place mosquitoes survive yr spherical.
What are the signs of West Nile virus?
WNV infections can have variable programs, however luckily generally the an infection is delicate and self-limited. In actual fact, in about 80 p.c of instances, the contaminated individual will show no signs and will not even know they’ve contracted the virus.
As much as 20 p.c of people that change into contaminated with WNV develop West Nile fever with signs together with fever, headache, malaise, muscle aches, and lack of urge for food persisting for 3 to 6 days. Roughly 20 to 50 p.c of instances could expertise the event of a pores and skin rash on the chest, abdomen and again. Sufferers total may additionally expertise swollen glands, eye ache, sore throat, nausea, vomiting, diarrhea, and stomach ache. Regardless of the identify “West Nile fever”, some sufferers report very low grade or no fever in any respect. These signs can final for just a few days or a number of weeks.
In lower than one p.c of instances, contaminated individuals contract extreme West Nile illness, (additionally known as neuroinvasive illness) leading to encephalitis (irritation of the mind), meningitis (irritation of the liner of the mind and spinal wire) or flaccid paralysis. The signs of extreme an infection can embrace excessive fever, extreme headache, neck stiffness, stupor, disorientation, coma, convulsions, muscle weak point, numbness, paralysis and even dying. Older age, alcohol abuse, diabetes and a few immunocompromised states (for instance, transplant sufferers) are important danger elements for creating a extreme West Nile an infection.
Folks usually develop signs of WNV between three and 14 days after being bitten by an contaminated mosquito and the signs could persist for a number of weeks, and in some instances trigger everlasting neurological results.
What’s the remedy for West Nile virus?
Milder instances normally resolve spontaneously and don’t require medical consideration, nonetheless, extra extreme instances, could require hospitalization for monitoring and help, though you will need to notice that there isn’t any particular remedy for WNV.
Anybody experiencing a excessive fever coupled with a extreme headache or different indicators of an infection ought to search speedy medical consideration.
How can I stop West Nile virus?
One of the simplest ways to keep away from contracting WNV is to stop mosquitoes from biting. In the summertime months, decrease exterior exercise between nightfall and daybreak, when mosquitoes are most lively. In case you should spend time outside throughout peak mosquito instances, put on lengthy pants and sleeves and use an insect repellant containing DEET, picaridin, IR3535, and a few oil of lemon eucalyptus and para-menthane-diol.
Picture credit score:
West Nile Virus Exercise by State – United States, 2013 (as of July 23, 2013), out there at: http://www.cdc.gov/westnile/statsMaps/preliminaryMapsData/activitystatedate.html, (accessed on July 28, 2013).