With summer well under way and mosquitos out in force, this is the time of year when public health professional start to worry about mosquito-borne diseases. The world’s most famous and deadly mosquito-borne disease, malaria, isn’t a problem here in the U.S., but others are. Eastern equine encephalitis virus, La Crosse virus, St. Louis encephalitis virus and others all caused multiple cases of encephalitis last summer, but West Nile virus remains the leading cause of viral encephalitis nation-wide, which was heavily covered in the media in 2012.
Last year was particularly notable for the number of West Nile virus cases recorded, causing 5,674 of the 5,780 mosquito-borne illnesses reported to the CDC in 2012. Of these 5,674, 2,969 (51%) were designated as neuroinvasive, meaning encephalitis or other neurological complications. 270 patient with neuroinvasive West Nile virus disease died (9%), representing a high mortality rate for viral infection. Considering that less than 1% of West Nile infections are believed to result in neuroinvasive disease it’s certain that non-neuroinvasive disease were drastically underreported, and more than 100,000 people may have actually been sickened by West Nile virus.
Now, all of that sounds quite frightening, but public health professionals are doing everything they can, and telling you what to do, to minimize the chance of this happening to you. County and State public health departments have already started conducting extensive surveillance, trapping and testing mosquitos for West Nile virus. When the virus is detected, local communities often commence pesticide spraying to kill adult mosquitos capable of transmitting the virus. If this kind of spraying is going to be conducted in your community, you WILL be notified and, although pesticides are generally not harmful to people, you’ll be advised to stay inside during praying out of an abundance of caution.
That’s what the government is doing, but there’s plenty you can do too. You can help with surveillance by reporting any dead birds you come across to local health departments, as these may indicate circulating virus in the area. A critical measure you can implement at home is regularly emptying standing water from birdbaths, kiddie pools, unused tires and any other receptacle where water accumulates. These objects are prime mosquito breeding grounds, and failing to keep them clean will absolutely lead to more mosquitos around your house. Keep down the number of mosquitos, and you keep down the risk of West Nile infection.
There’s also plenty you can do to protect yourself and your family. Wearing inect repellant containing up to 50% DEET is always important when spending time outdoors in the summer, and for instructions on proper application and safety information, the CDC website is very informative. Additionally, while a burden, wearing long sleeves and pants offers additional protection. The CDC recommends it, but we all know most people aren’t listening to that advice, especially me. Insect repellant is the practical way to go here.
You will likely start to see West Nile virus mentioned in the media more and more over the next few weeks and months, particularly if this season looks like last season. However, keep in mind the chances of being infected are low, and only 20% of infected people get sick at all! Less than 1% of these will get neuroinvasive disease. With the highest risk part of the year approaching it is worth your time to learn what the symptoms of West Nile infection are (flu-like), and what to do if you suspect you or a family member has West Nile virus disease (call your doctor immediately). For more detailed information, look to the CDC West Nile virus page.
The important thing is to be aware of what you can do to protect yourself from mosquito bites, and get out and enjoy the summer. West Nile virus infection is serious, but it shouldn’t keep you out of the pool, off the golf course, or away from the beach.