CRITTERS: Mosquitoes
© 2006 RogueTurtle.com
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First in a new series on nuisance pests
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Any trip into the great outdoors has to be prepared for insects and "critters" that can not only make your life miserable, but can actually cause you physical harm...or death. Any insect bite to a person who is allergic to stings can be fatal. It's called ANAPHYLACTIC SHOCK.
ANAPHYLACTIC SHOCK CAN KILL
The severest form of allergy which is a medical emergency. It is often a severe and sometimes fatal systemic reaction in a susceptible individual upon exposure to a specific antigen (such as wasp venom or penicillin), particularly after initial exposure once before. The symptoms are characterized especially by respiratory symptoms, fainting, itching, urticaria (skin lesions), swelling of the throat or other mucous membranes and a sudden decline in blood pressure.
Anaphylaxis means the opposite of protection. The term "Anaphylaxis" came about years ago when some scientists were trying to protect dogs from poisons by immunizing them with small doses of poison. They found that after giving the dogs a second dose of poison, the dogs suddenly died. The term for protective immunizations is "Prophylaxis". These scientists used the term "Anaphylaxis" in their report, since this was the exact opposite of the reaction they were trying to achieve. The rest is history.
Most anaphylactic reactions occur after the SECOND bite or sting.
Most people who reach adult age probably already know which bugs to avoid. Young children, however, may not have been exposed to the great outdoors for any long period of time. Today, the mere bite of the once (relatively) harmless mosquito can result in severe health hazards. Children who have not been exposed to bee stings, ant bites, or the like, may develop severe symptoms after the first, or (most likely) the second bite.
MOSQUITO BITES: #1 DANGER
The female is the only mosquito that can actually "bite" or draw blood from a person, a male can't. They usually bite at a constant rate of about 5 bites per hour, and before sunrise and sunset, increase their blood intake. This insect can spread some of the worst diseases in the world to people. For example, the Anopheles mosquito carries malaria, and the genus Aedes carries the yellow fever virus. The diseases are mostly associated in the areas by the equator, but mosquitoes live all over the world, delivering diseases everywhere. The housefly mosquito can transmit parasitic worms and encephalitis virus.
A mosquito picks up malaria parasites from other people. The parasites then stay in her salivary gland. Once she puts the saliva on the human, the parasites go free in the bloodstream. The parasites will go in the liver and multiply. That is when you get a serious case of malaria. Mosquito diseases are very deadly. They cause about 1,000,000 deaths per year world-wide.
ARBOVIRAL ENCEPHALITIDES
The following mosquito-transmitted viral diseases cause brain inflammation, a.k.a. encephalitis:
Eastern Equine Encephalitis
EEE virus (EEEV) occurs in the eastern half of the United States where it causes disease in humans, horses, and some bird species. Because of the high mortality rate, EEE is regarded as one of the most serious mosquito-borne diseases in the United States. It generally takes from 3 to 10 days to develop symptoms of EEE after being bit by an infected mosquito.
The main EEV transmission cycle is between birds and mosquitoes.
Many persons infected with EEEV have no apparent illness. In those persons who do develop illness, symptoms range from mild flu-like illness to EEE (inflammation of the brain), coma and death. The mortality rate from EEE is approximately one-third, making it one of the most deadly mosquito-borne diseases in the United States. There is no specific treatment for EEE; optimal medical care includes hospitalization and supportive care (for example, expert nursing care, respiratory support, prevention of secondary bacterial infections, and physical therapy, depending on the situation). Approximately half of those persons who survive EEE will have mild to severe permanent neurologic damage.
There were approximately 220 confirmed cases in the US between 1964 and 2004. The average is 5 cases per year, with a range from 0-15 cases per year. States with the largest number of cases are Florida, Georgia, Massachusetts, and New Jersey. EEV transmission is most common in and around freshwater hardwood swamps in the Atlantic and Gulf Coast states and the Great Lakes region. Human cases occur relatively infrequently, largely because the primary transmission cycle takes place in and around swampy areas where human populations tend to be limited.
There is no EEV vaccine available and it doesn't look like there will be in the near future. There is no specific drug treatment available either.
Japanese Encephalitis
This is a virus that in its acute stage can progress to paralysis, seizures, coma and death. However, the majority of infections are not that severe. The Japanese Encephalitis is the leading cause of viral encephalitis in Asia, with 30-50,000 cases reported annually. The good news is that there is only about 1 case per year reported for US civilians and military personnel traveling to and living in Asia. There have been rare outbreaks in US territories in the Western Pacific. Inside the USA, the incident rate is low, approaching zero. But, if you live in Australia, watch out, it is slowly approaching your area.
La Crosse Encephalitis
This one IS in the USA. Severe cases progress to seizures and coma, but the majority of the infections are sub-clinical or result in mild illness. There are about 70 cases reported each year in the USA. The fatality rate is less than 1 percent. However, hospitalization is usually required and subsequent neurological symptoms seem to resolve within one year.
The mosquitoes carrying the La Crosse encephalitis use water-filled tree holes, artificial containers (tires, buckets, etc.) in addition to tree holes to breed. The Treehole Mosquito (Aedes triseriatus) cycles with vertebrate hosts (chipmunks, squirrels) and will survive winter. The traditional endemic focus is in the Great Lakes states, with increasing cases reported in Mid Atlantic States. The rural poor seem to be the most affected group. If you are surviving in the woods, you will also fall into this category.
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St. Louis Encephalitis
Only virus-infected mosquitoes can transmit this disease. You cannot catch it from casual contact with an infected patient. The disease is transmitted between birds and mosquitoes, and occasionally an infected mosquito will bite a human being who then gets the disease.
 
Source: CDC
St. Louis Encephalitis Symptoms
Mild infections occur without apparent symptoms other than fever with a headache. More severe infections are marked by headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, occasional convulsions (especially in infants) and spastic (but rarely flaccid) paralysis. The incubation period from bite to onset of symptoms is from 5 to 15 days. Fatality rates vary from 3 to 30 percent, with the elderly the most common deaths. Since 1964 there have been 4,478 reported cases of St. Louis encephalitis, with an average of 128 cases reported annually.
This virus is found throughout the United States, but primarily in temperate areas. St. Louis encephalitis cases primarily occur in the late summer and early fall. In the southern US, where the climate is milder, St. Louis encephalitis can occur year round.
WEST NILE VIRUS
As of June 13, 2006, avian (bird), animal, mosquito WNV infections have been reported to the CDC from: Arkansas, California, Florida, Idaho, Illinois, Indiana, Michigan, Missouri, New York, Tennessee, Texas, Utah, West Virginia and Wyoming. Human cases have been reported in Colorado, Mississippi and Texas. The virus is out there, all over the country. Like all the other encephalitis diseases, the West Nile virus (WNV) is now a threat to public and animal health. The most serious manifestation of WNV infection is fatal encephalitis in both humans and horses, as well as in certain domestic and wild birds. WNV has been a significant cause of human illness in the US in 2002 and 2003, and it's not over yet. The virus was first identified in Egypt in the 1950's, hence its name. It was first discovered in the USA in 1999. Very few genetic changes have occurred in the strains circulating in the United States. So far, only Hawaii, Alaska and Oregon have escaped from its toll. For unknown reasons, deaths among infected birds have only occurred in the United States, Israel, Canada, and Mexico.
Mosquitoes become infected when they feed on infected birds, which may circulate the virus in their blood for a few days. Infected mosquitoes carry virus particles in their salivary glands and infect susceptible bird species during blood-meal feeding. Bird reservoirs will sustain the virus for 1 to 4 days after exposure after which the host bird may develop life-long immunity.
While there is no documented evidence of animal-to-person transmission of WNV apart from mosquitoes, persons should avoid bare-handed contact with dead animals, and use gloves or double plastic bags.
Treatment
There is no specific treatment for WNV. In severe cases, treatment consists of supportive care that often involves hospitalization, intravenous fluids, respiratory support, and the prevention of secondary infections. Clinical trials are ongoing, but no specific cure has been found.
PUBLIC ENEMY #1
Miss Mosquito. Males can't bite.
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Western Equine Encephalitis
Western Equine Encephalitis symptoms range from mild flu-like illness to full-blown encephalitis, coma and death. There have been 639 cases reported since 1964. Survivors may have mild to severe neuralgic disorders after recovery. There is no licensed vaccine for this disease. There are no known therapeutic drugs for this disease. In other words, it's just like all the others. If you get it, you face a long recovery time - if you recover at all.
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WORLD TRAVELERS BEWARE
There are a lot of other diseases that tourists can get just by traveling overseas where mosquito control is NOT a function of the government:
Dengue Hemorrhagic Fever, Malaria, Rift Valley Fever and Yellow Fever, to name a few.
PREVENTION
The best defense against all the diseases listed so far is PREVENTION. By avoiding getting bitten, you avoid the disease. Most government agencies, including the Center for Disease Control (CDC) tell you that using insect repellent will allow you to continue to play and work outdoors with a reduced risk of mosquito bites. Apply repellent when you are going outdoors, even if you don't notice mosquitoes. There is a good chance they are still around, particularly if you are moving through woodland areas or areas with standing water. Many of the mosquitoes that carry West Nile virus bite between dusk and dawn. It is important to use repellent during these time periods. Other mosquitoes only bite during the daytime, so using repellent ALL the time is very important.
MACHO MAN: "That little mosquito wouldn't DARE to bite me!" Yes, it would.
Female mosquitoes bite people and animals because they need the protein found in blood to help develop their eggs. Mosquitoes are attracted to people by skin odors and carbon dioxide from breath. The active ingredients in repellents make the person unattractive for feeding. Repellents do not kill mosquitoes. Repellents are effective only at short distances from the treated surface, so you may still see mosquitoes flying nearby. The CDC believes that only two products currently registered with the Environmental Protection Agency have clearly demonstrated a high degree of long-lasting protection: DEET and PICARIDIN. Any repellant you purchase should have a high percentage of either of these two chemicals included in the contents.
DEET is an effective active ingredient found in many repellent products and in a variety of formulations. This substance was discovered and developed by scientists at the U.S. Department of Agriculture and was patented by the U.S. Army in 1946. It was subsequently registered for use by the general public in 1957. It is a broad-spectrum repellent that is effective against mosquitoes, biting flies, chiggers, fleas, and ticks.
In 2002, a study showed:
- A product containing 23.8% DEET provided an average of 5 hours protection from bites.
- A product containing 20% DEET provided almost 4 hours of protection.
- A product with 6.65% DEET provided almost 2 hours of protection.
- Products with 4.75% DEET were able to provide roughly 1 and 1/2 hours of protection.
Be careful when applying repellents to yourself (and others). Repellents sprayed directly into the eyes will cause irritation and some formulations will damage eye glasses or synthetic (plastic) materials. Take your eye glasses off, and close your eyes if spraying a face. Watch out for the over-spray. I have had two watch faces ruined by a bug spray, and one flashlight lens went opaque from it. Better than a direct spray, apply the chemical to your hands and then carefully rub it onto your face.
Closely monitor the use of insect repellents on children. If they seem to be reacting to the spray, stop using it immediately and wash the skin surface with soap and water. Children should use DEET concentrations of 10% or less. Very small children may put their hands in their mouths, so avoid spraying the hands of very small children or infants.
Thin material will not stop the bite of an aggressive mosquito. Spray thin outer garments with the same repellent as your skin.
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Note:
It is worth noting that HIV is NOT TRANSMITTED by mosquitoes. The virus neither survives nor replicates when inside a mosquito.
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Cutter Advanced® is an alternative spray to DEET. It contains PICARIDIN, the second most used ingredient used after DEET. According to Cutter, it provides "long lasting protection that can be used by the entire family". Other Cutter products use DEET.
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Deep Woods Off® uses 25% DEET in most of their products. I personally use this brand a lot, but you can use what you desire. I like the "towelette" idea, particularly for applying to small children who won't close their eyes when you spray around them. Lower dose sprays are also available.
Deep Woods Off "Sportsman" uses 25% or 30% DEET
Deep Woods Off "Sportsman Insect Repellent I" uses 98% DEET
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Note:
Other than anaphylactic shock from a sting, the diseases spread by the mosquito are the biggest insect danger to humans in the woods.
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I found these "home-brewed" mosquito repellants on the following website: mercola.com.
I cannot vouch for any of them.
- While there are many ways to deter mosquitoes from biting you, some are more toxic than others. The following suggestions give you easy ways to repel these pests:
- Use Bounce Fabric Softener Sheets--just wipe on and go. This is great for babies.
- Supplement with one vitamin B-1 tablet a day from April through October. Add 100 mg of B-1 to a B-100 Complex daily during the mosquito season.
- Don't eat bananas during mosquito season--mosquitoes love bananas! There is something about how your body processes the banana oil that attracts these female sugar-loving insects.
One of the best natural insect repellents is Vick's Vaporub®.
- Planting marigolds around your yard works great as a bug repellent because the flowers give off a fragrance bugs do not like. This is a great way to ward off mosquitoes without using chemical insecticides.
- Campers agree that the very best mosquito repellant is Avon Skin-So-Soft® bath oil mixed half and half with rubbing alcohol. (Not all campers...I don't agree, for one. But, it's worth a try. RT)
- One of the best natural insect repellants we use in Texas is made from the clear liquid vanilla that is sold in Mexico. It is reported to work great for mosquitoes and ticks, and spreading a little vanilla mixed with olive oil on your skin smells great. (Please don't use this one in "Bear Country". They will think you are food.)
- Commercial mosquito dunks will kill mosquito larvae before they become mosquitoes. They are (mostly) environmentally sound biological mosquito controls that contain no toxic chemicals. Each dunk effectively treats up to 100 square feet of surface water regardless of depth for about 30 days. Dunks may be broken into smaller pieces to treat small areas. Unused and dried out dunks retain their potency indefinitely, so you can store extras for the long summer season. Put them in fountains, ponds, rain gutters, flowerpot trays, and anywhere water may pool.
- Citronella soap is a product that started in the Bahamas and Belize. The soaps are made with olive oil for moisture and great lather, Aloe Vera to soothe the skin, and citronella oil to repel mosquitoes. For high intensity protection you can burn citronella incense. Mosquitoes avoid citronella and they hate the smoke.
- Citronella essential oil (Java Citronella) is considered to be the highest quality citronella on the market. The best quality is steam distilled from the grass giving it a fresh, sweet woody aroma. It blends well with geranium, cedar wood and other citrus oils. It is 100 percent pure essential oil--no additives, no dilutants, no adulteration, just safe mosquito repellent.
- Electronic repellents utilize one to two sound frequencies to simulate dragonflies and other male mosquitoes, creating a competitive environment for the blood-sucking female. These devices come with Velcro bands for wearing on your wrist or ankle, or on your pocket or belt. This makes for a versatile, compact unit that you can take anywhere for protection. Some units even have a built-in red flashlight for nighttime use.
- When all else fails--get a frog!
The last one, I can vouch for. However, training the frog will take a LONG time. This same web site goes on to bad-mouth DEET, one of the two CDC repellants approved by the FDA. I would try the above remedies, and if one or more works for you, great. If they don't, they don't.
FIRST AID FOR MOSQUITO BITES
Avoiding mosquito bites should be your first line of defense, but if the little bloodsuckers bite, you'll need some defense against itching and infection.
Steps:
- Wash the infected area with soap and water as soon as you recognize that you've been bitten. Try to keep the site clean and dry until the irritation abates.
- Avoid scratching. Although a mosquito bite should itch for only a few days, continual scratching will increase your discomfort and may prolong the itching.
- Make a paste of baking soda and water, using just enough water to make the paste sticky. Spread the mixture on the bites.
- Rub soap directly on the bite. This is an oft-repeated home remedy for mosquito bites.
- Apply an ice pack or ice wrapped in a washcloth to the bite area.
- Use calamine lotion or a topical anesthetic containing pramoxine to help relieve pain and itching.
- Purchase 1-percent hydrocortisone cream to alleviate the itching. Follow directions on the package for safe use.
- Use an anti-inflammatory drug such as Ibuprofen or Benadryl to reduce any accompanying swelling or redness.
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