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Friday, Apr. 29, 2016

Brown recluse season is here

Sunday, April 16, 2006

Nevada, Mo. -- Spring time is here, the weather is tumultuous, the birds are back and Easter is around the corner; everywhere, a mystifying insect is hatching ready to feast on the sufficient supply of flies and other insects that pervade the Midwest -- the spider.

One spider in particular, he brown recluse (Loxosceles reclusa), is extremely dangerous to humans. These spiders' bites are often implicated with necrotic skin lesions and can cause illness and other complications in humans, up to and including death in some cases.

These spiders are rather reclusive in their habitats as their name implies. Typically nocturnal, they attack prey with their venom which subdues them. The recluse itself refers specifically to only one species of spider that lives in regions of Missouri and Kansas.

Some studies have shown that the brown recluse is so very common and abundant that a researcher found 40 brown recluses in a barn within 75 minutes.

In the Midwest, the recluse is an extremely common house spider. Recluses do bite humans despite their apparent shyness, but won't "attack" a person.

Pat Miller of the Vernon County University of Missouri Extension office said, "They don't attack unless they are smashed into someone, by putting on clothes or rolling over on them when they are in bed."

Recluse spiders will bite humans when they are trapped between flesh and surface area. To reduce a bite risk, keep beds away from walls, remove bed skirts as well as any item under the bed so that the only pathway to the bed is up the legs.

Experts also advise keeping clothing off the floor. If it is on the floor, shake it vigorously before dressing. Also, experts agree that storing all intermittently used items such as gardening clothing, baseball mitts or roller skates in spider-proof boxes or bags will aid in prevention.

The life cycle of the brown recluse last up to two years, according to a university of Iowa study. The eggs have an off-white silken quality to their appearance and are typically laid in small dark areas. The recluses' development is slow and greatly influenced by the availability of food and weather conditions. It typically takes a recluse 10 to 12 months for them to reach maturity.

Robin Harrington, a registered nurse at the Nevada Wound Care Clinic, said that the clinic typically receives one to three cases a year, and typically the bites are necrotic lesions. Harrington said, "People should watch for them while they are changing clothes, recluses are around more in the spring and fall."

Harrington described the treatment, a multi-step process. "The lesions, if necrotic, typically undergo debridement, which is when we take the necrotic tissue off. People don't realize they have been bit. Within a few hours of bite time flu like symptoms emerge."

Harrington advises those who have been bitten should seek medical attention immediately. Brown recluse bites may go unnoticed for a period of time, or the person might begin to experience an itching or burning sensation as early as 30 minutes from the time that they were bitten. Typically, within eight hours a necrotic spot may develop which can enlarge to the size of a silver dollar or larger. If these symptoms appear, then the area can become sunken and ulcerated. Some reaction may or may not occur with these bites, typically there can be a fever, severe chest or stomach pain, nausea and/or vomiting. Some of these bites have been fatal. A majority of the fatalities occur in children under seven.

The University of Missouri advises those bitten to remain calm and immediately seek attention.

Also, apply an ice pack to the bite area to relieve swelling and pain.

If possible, collect the spider and bring to the physicians office so that they may be able to diagnose and treat the bite more efficiently.

Currently, no commercial antivenoms are available. Some physicians may administer high doses of cortisone type hormones to combat hemolysis and other complications. Treatment with an oral dapsone (an antibiotic used mainly for leprosy) has been suggested to reduce the degree of tissue damage.

Currently, an effective therapy has not yet been found.

An Integrated Pest Management system is the best way to control these spider populations, especially in older homes. IPM includes three components, sanitation, exclusion and chemical techniques.

"The most important step to take in reducing the recluse population, is to clean up the junk in your home," said Miller.

Sanitation includes home cleaning, dusting, vacuuming and washing the floors in the closet area and other areas that are not used quite as frequently. When vacuuming, be sure to remove webs and it is advisable to place sticky boards down for pest management monitoring. Miller advises placing them along baseboards and any other cracks and crevices in the home.

The second component of pest management is to seal all the cracks and crevices in the structure, eliminating places where spiders might be able to enter the home.

Also, the experts advise cleaning the outside area around your home efficiently to reduce the breeding areas for these spiders and other pests.

Finally, the third technique utilized in the IPM plan includes chemical techniques, using pesticides labeled for spider control. Pesticides have changed in recent years and local experts say that some foggers might not work on these insects due to their reclusive nature. The pesticide itself, has to be able to infiltrate the area, and that might mean going through walls and other areas where foggers cannot access, said the experts.

Some say Osage Oranges have an ability to deter brown recluses. Also known as hedge apples, these are a common feature in the Midwest, which were planted before the invention of barbed wire in the 1880s to achieve property line fencing around their property. The apples themselves, produced in the fall can be used for pest management.

According to folklore and researchers at Iowa State University, placing hedge apples around the house can keep cockroaches away as well as spiders and other pests. Its effectiveness in repelling the brown recluse specifically is unconfirmed.

Researchers have found a roach repellent compound in these fruits and they are non toxic to humans, so no harm will come form this method. It is important to be aware of the danger and damage these arachnids can cause in the home. The frequency of the cases in the Midwest and the mortality rates to children should be taken into consideration, expert say. While spring has sprung so to has the spider populations.

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