Babesiosis; Human granulocytic anaplasmosis (HGA)
Everyone should avoid specific tick-infested areas, including tall grass, woods, and bushes where ticks tend to congregate. If this is not possible, people should take additional preventive measures. The U.S. Centers for Disease Control (CDC) also recommends:
Mowing the grass regularly, clearing away leaves, and placing wood chips as a barrier around a lawn can help greatly reduce the tick population.
Permethrin for the Lawn. Insecticides can reduce tick infestation by 90%. Insecticides should be applied in late spring or early fall in a strip a few feet wide along the perimeter of the lawn where small animals are likely to enter or live.
The most commonly used insecticides are pyrethrins, which are compounds derived from the Chrysanthemum family. They are available as natural products or in synthetic forms (permethrin). They are poisons that affect the nerve system of insects. They are safe, particularly the natural products, for humans and pets. All pyrethrins are highly toxic for certain fish and slightly toxic for birds, such as mallard ducks. Some people do experience an allergic reaction to them. As with all insecticides, there is some concern about the possible consequences of long-term exposure, but to date there is no evidence of any harm.
Cardboard tubes stuffed with permethrin-treated cotton are available in hardware stores. The tubes are placed where mice can find them (dense, dark brush) and collect the cotton for lining their nests. The pesticide on the cotton kills any immature ticks that are feeding on the mice. Best results are obtained with regular applications early in the spring and again in late summer.
Other Pesticides. Other tick-killing spray pesticides that have been used include those containing diazinon, chlorpyrifos, and carbaryl. Animal studies have reported severe toxic effects associated with these chemicals. Some of these chemicals are being phased out for home use. Parents should balance the effects of a very negligible risk for a highly treatable infection versus excessive use of possibly harmful chemicals.
Fencing. Deer fencing, a wire fence about 3 - 4 yards high, or electrified fencing can be helpful, but it is costly to put up and maintain.
Ivermectin. Corn that is laced with the anti-parasite medication ivermectin (Ivomec and others) and then eaten by deer helps prevent ticks from feeding on them. Ivermectin is present in a number of products used by veterinarians to control parasites, such as heartworm. It has potential toxic effects in collie or collie mixed breeds, however.
Hiking and camping in the Northeastern woods carries a significant risk for tick bites and Lyme disease (3% in one study). Anyone out in the woods during tick season should wear protective clothing, including:
Simply washing clothes will not kill ticks. After venturing outdoors, people should run their clothes through a dryer at high temperature for a half hour. Spraying clothes with solutions containing permethrin (Permanone, Duranon, Permakill) affords additional protection. Keep in mind that these sprays should not be applied to the skin. Clothes should not be retreated with permethrin for 48 hours unless they are washed.
DEET. Most insect repellents contain the chemical DEET (N,N-diethyl-meta-toluamide), which remains the gold standard of currently available mosquito and tick repellents. DEET has been used for more than 40 years and is safe for most children when used as directed. Comparison studies suggest that DEET preparations are the most effective insect repellents now available.
Concentrations range from 4% to almost 100%. The concentration determines the duration of protection. Most adults and children over 12 years old can use preparations containing a DEET concentration of 20 - 35% (such as Ultrathon), which provides complete protection for an average of 5 hours. (Higher DEET concentrations may be necessary for adults who are in high-risk regions for prolonged periods.)
DEET products should never be used on infants younger than 2 months. According to the Environmental Protection Agency, DEET products can safely be used on all children age 2 months and older. The EPA recommends that parents check insect repellant product labels for age restrictions.
If there is no age restriction listed, the product is safe for any age. The American Academy of Pediatrics recommends that children use concentrations of 10% or less; 30% DEET is the maximum concentration that should be used for children. In deciding what concentration is most appropriate, parents should consider the amount of time that children will be spending outside, and the risk of mosquito bites and mosquito-borne disease.
When applying DEET, take the following precautions:
Picaridin. Picaridin, also known as KBR 3023 or Bayrepel, is an ingredient that has been used for many years in repellents sold in Europe, Latin America, and Asia. A product containing 7% picaridin is now available in the United States. Picaridin can safely be applied to young children and is also safe for women who are pregnant or breastfeeding. Insect repellents containing DEET or picaridin work better than other products for protection against ticks.
Self-Inspection. The tick is unlikely to transmit the infection within 3 days of the bite, but prompt removal is still important. The following tips are important for self-inspection:
Tick Removal. If an attached tick is discovered, there is no reason to panic. Do not put a hot match to the tick or try to smother it with petroleum jelly, nail polish, or other noxious substances. This only prolongs exposure time and may cause the tick to eject the Lyme organism into the body.
The safest and most effective way to remove an attached tick is:
The LYMErix Vaccine. The LYMErix vaccine, previously approved, was taken off the market because of poor sales and because of problems encountered with its use. A primary limitation was that the vaccine was effective only in about 75% of cases, and the effects were not long lasting. There were also reports of arthritic and neurologic symptoms in a few vaccinated people. There is no definitive evidence, however, that the vaccine was responsible for these symptoms.
Since dogs, cats and even horses can get Lyme disease, inspect pets for ticks regularly. Symptoms in animals include lameness and lethargy. Dogs are much more likely to get Lyme disease than cats, but both are susceptible. In dogs, symptoms occur 2 - 5 months after a tick bite and include fever, lameness, and lack of appetite. In rare cases, Lyme disease can cause kidney damage in dogs if it is left untreated.
Preventive Products. Products containing permethrin (Bio Spot, EXspot), amitraz (Preventic), or fipronyl (Frontline) can be used safely on dogs. Not all of these products are safe in cats. Only permethrin is also effective against fleas. Some veterinarians suggest that the combination of BioSpot and Preventic is very effective. [Another product -- selamectin (Revolution) -- is sold for flea and tick control, but it appears to have very limited effect against ticks.]
Pet Vaccines. Lyme disease vaccines are available for dogs, but they do not offer total protection. Veterinarians vary in their use of the vaccines.
Treatment. As with people, antibiotics almost always cure the infection in animals.
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