West Nile Virus

In experiments, the Asian Tiger Mosquito was found to transmit West Nile Virus

Classified by the Center for Disease Control as part of the Japanese encephalitis strain of flavivirus (yellow fever) and also similar to dengue fever, West Nile Virus first came to widespread public attention in the United States following an outbreak in Queens, New York in 1999 and gained further notoriety during the epidemic of 2002. The virus is transmitted to humans principally through mosquito bites, though it can affect other mammals including horses, dogs, cats, and rabbits (among others) as well as a variety of birds including crows and robins.

Infection, Incubation, and Symptoms

Infection is humans has proven to be largely asymptomatic; the Louisiana Department of Health and Hospitals reports that 90% of people infected with West Nile Virus never present symptoms. Others contract West Nile Fever, a condition which includes feverishness, fatigue, sore muscles and rash.

Some extreme cases develop into one of several neuroinvasive diseases called West Nile Meningitis, West Nile Encephalitis, and West Nile Meningoencephalitis. Encephalitis is an inflammation of the brain; meningitis is an inflammation of the membrane around the brain of of the spinal cord. Meningoencephalitis is an inflammation of both.

Transmission

The virus is transmitted from mosquitoes to birds, who act as incubators and who pass the strengthened virus to mosquitoes via further bites. According to the CDC, the disease is not transmitted from human-to-human contact, although one documented case involved a mother passing it to her infant child through breast milk. People older than 50 and patients with compromised immune systems are at higher risk of becoming seriously infected.

In 2009, U.S. health officials recorded 663 confirmed cases of West Nile Virus infection among humans. Of these, less than one percent of those infected contracted one of the neuroinvasive diseases.

Prevention

Mosquito Magnets

An electronic microscope image of the West Nile Virus

The CDC recommends applying EPA-approved insect repellent to both skin and clothing, or wearing long-sleeved shirts and full-length pants (not shorts) when weather permits. Insect netting should be placed over children’s cribs and strollers.

Homeowners can reduce the presence of mosquitoes in their home and on their property by installing window and door screens to keep mosquitoes from getting into the house. As mosquitoes tend to congregate around standing water, draining all flower pots and pans, storm drains and gutters will also discourage mosquitoes from lingering around the house and yard. Finally, a variety of mosquito traps are available which act to replicate human breathing and temperatures, working to divert mosquitoes from attacking human targets.

Where to Get More Information

Additional information is available at the CDC’s West Nile Virus information page

Mosquito MagnetsIt’s sometimes said that the female of the species is deadlier than the male, and that’s certainly true of mosquitoes. Despite common knowledge, it’s only the female mosquito that bites – and only when she’s pregnant.

But mosquitoes breed often and in large amounts, so managing their population is a goal that needs constant attention. Unfortunately, many homeowners are slow and confused about what steps to take.

Every breath we take: mosquito behavior

Mosquitoes and other airborne insects are always annoying but many are sometimes dangerous: many carry potentially deadly diseases including malaria, dengue fever, West Nile virus, and several strains of encephalitis. Worse still, mosquitoes are attracted to humans by the scent of carbon dioxide. We attract mosquitoes, in other words, every time we breathe.

Bad news for the Southern United States

Mosquitoes typically congregate in low-lying areas near still water or areas prone to high humidity, the same areas that are often the sites of suburban and semi-rural housing developments. It’s not uncommon, especially in the Southern United States, for suburban residents to find themselves seemingly besieged even in their own backyard. An old joke describes the mosquito as “the state bird of Louisiana.”

Treating mosquito bites: alternate solutions

Given the mosquito’s almost universal presence, it’s no wonder that a number of folk remedies find new generations of fans every year. Some of the more common include rubbing toothpaste or vinegar on stings, while other people prefer to apply ice directly to the stung area of the body to slow swelling and numb the nerve endings.

Mosquito magnets and other defenses

Mosquito MagnetAnother solution involves installing mosquito magnets, which use propane to chemically mimic human CO2 exhalation as well as heat and moisture signals. These relatively small and lightweight machines are often electrically powered and can safely protect most backyards regardless of time of year or number of people.

Mosquito MagnetKnowing the right places to set up your mosquito magnet can make a huge difference in the comfort and safety of your backyard or other outdoor area. Mosquito magnets attract and trap mosquitoes and other flying pests anytime and wherever they’re used, but strategically placing them in certain areas can greatly boost their performance.

Get ‘Em Where They Live

Mosquitoes, black flies (sometimes called no-see-ums) and other flying pests tend to congregate in areas of standing water and thick grasses and vegetation, and out of direct sunlight – for example, around ponds and in the woods ringing most suburban developments. These pests also breed where they live, with females actively seeking blood only when they’re pregnant.

Placing a mosquito magnet in these high population-density areas will deploy its trapping capacity where it can do the most good, using its human-mimicking humidity and carbon dioxide-replicating technology to catch the most number of mosquitoes.

Keep Your Mosquito Magnet Close – But Not Too Close

Mosquito Magnets

The Anopheles albimanus mosquito

Another strategy is simply to place your mosquito magnet near wherever you and your family and friends will spend the most time outside. The backyard patio, deck, or around the family swing-set and gazebo are all potential sites, as well as the swimming pool, community baseball diamond, and tennis courts.

Simply place the mosquito magnet thirty to forty feet away from the area you plan to use, in an open area upwind of the protected site. This will help to keep the insects away from you and others, so that the insects don’t attack you instead. If possible, place the mosquito magnet in the shade, as mosquitoes tend to shun direct sunlight.

When You Should Expect Results

Most mosquito magnet models significantly reduce local mosquito and other flying insect populations within seven to ten days. In many cases, after four to six weeks the female population of the coverage area will have almost completely disappeared. Remember to regularly change its attractant cartridges, replace its power supply, and to clear out its trap container to keep your mosquito magnet operating in top condition.

A key part of mosquito magnet technology rests in its ability to mimic the carbon dioxide emissions (breathing out) that lures pregnant mosquitoes towards human beings. Mosquito magnets also use one of two chemical attractants to further lure the bugs towards their capture mechanisms.

How Attractants Work

Most mosquito magnets use one of two chemical attractants: Octenol or Lurex3. Where the mosquito magnet owner lives will largely determine the best attractant to employ. In either case, manufacturers recommend that owners replace the attractants in their mosquito magnets every three weeks.

Octenol attracts mosquitoes and black flies (no-see-ums) by mimicking human breath. Lurex3 replicates skin emanations.Though both aggressively lure mosquitoes towards their magnets, they each attract specific types of mosquitoes.

The Rules of Attraction

Asian TIger Mosquito

the Asian Tiger Mosquito

Octenol is recommended for mosquito magnet owners living in the Mid-Atlantic and Eastern Seaboard states, the Midwest, the Pacific Northwest, the California mainland and Colorado, Nevada, and Alaska.

Lurex3, which specifically targets the Asian Tiger mosquito species, is recommended for the Deep South, the Southern California coastline, Kansas, Utah, and Hawaii. Lurex3 specifically targets the Asian Tiger Mosquito, a species that in recent years has migrated and adapted to cooler climates well north of their traditional tropical habitats. However, the Tiger mosquito commonly hibernates during the cooler months in these more northerly climes.

Lurex3 is recommended for mosquito magnet owners in areas where the Asian Tiger Mosquito is the dominant pest. In other areas, such as coastal regions where the dominant pest is the salt marsh mosquito or no-see-um fly, Octenol offers better effectiveness in luring its prey for residents living up to ten miles inland.

Where and How to Buy

Both varieties of attractants are sold in packs or canisters wherever mosquito magnets are sold, distributed by a variety of manufacturers.