WebMD Live Events Transcript
Fun in the sun these days requires some extra caution, thanks to the West Nile virus. Add insect allergies, fire ant infestations, and disease-carrying ticks to the mix, and suddenly summer seems scary. On June 1, 2004, we took a look at safely protecting yourself and got treatment tips from dermatologist Dirk Elston, MD.
The opinions expressed herein are the guests' alone and have not been reviewed by a WebMD physician. If you have questions about your health, you should consult your personal physician. This event is meant for informational purposes only.
MODERATOR: Welcome to WebMD Live, Dr. Elston. With so many critters out there carrying disease, is it safe to spend time outdoors?
ELSTON: It depends on where you are outdoors. There are problems in much of the country with West Nile fever in the summer months that's been highlighted in the press, and there are other conditions that are prevalent in various regions that have been around much longer than West Nile fever. They include:
- Rocky Mountain spotted fever occurs throughout the U.S., but is most prevalent in the Southeast, with the highest incidences in South Carolina. There are similar rickettial diseases throughout the country, especially in the Southwest.
- St. Louis encephalitis in the Midwest and both western and eastern equine encephalitis.
- Lyme disease is especially prevalent in the Northeast and pockets of the Northwest.
West Nile and the equine encephalitis viruses are mosquito borne. Lyme disease, Rocky Mountain spotted fever, and other rickettial diseases are tick borne. In endemic areas an application of permethrin applied to clothing, and an insect repellant, especially those with DEET or picaridin, are recommended for protection.
MEMBER QUESTION: Do any stinging insects ever carry disease, or is the risk primarily from allergic reactions to their stings?
ELSTON: That's true; stinging insects have been associated primarily with staph infections and rarely with fungal infections, such as sporotrichosis, but biting, rather than stinging, arthropods account for the spread of most disease.
MEMBER QUESTION: I realize you're a skin doc and not a product tester, but I have to ask: Do you know of any expert opinion or tests of those mosquito traps that run on propane? We are driven crazy by hordes of mosquitoes in our yard in the summer. Sometimes we can't even go outside they're so bad. Four-hundred bucks for a trap doesn't seem so bad at those times.
ELSTON: There has been some objective evaluation published of mosquito traps, primarily the Mosquito Magnet models, which use propane to generate carbon dioxide as well as using Octonal as a mosquito attractant. There is published evidence they are effective, although Octonal may repel mosquitoes in some regions of the Southeast and the manufacturer will advise specific areas where the Octonal should not be used. There are other traps that use adhesives and other chemical attractants and have not been as well studied.
|"The American Academy of Pediatrics recommends that DEET be used in a concentration of 10% or less for children, and many of these products are available."|
MEMBER QUESTION: What is the best way to reduce the itch from mosquito bites? Are there any home remedies that work?
ELSTON: There are plenty over-the-counter products, such as camphor and menthol products and those that contain pramaxine. The topical Benadryl may be associated with allergic contact dermatitis and is best avoided, but topical corticosteroids, such as the hydrocortisone products available over the counter, are effective.
MEMBER QUESTION: Do deer flies carry any diseases?
ELSTON: Yes, they do. Deer flies carry a number of diseases to include tularemia and in other parts of the world a parasitic worm called Loa loa that infects the eyeball.
MEMBER QUESTION: Can you get sick from black fly bites? On the Jersey shore sometimes we get huge biting flies.
ELSTON: Black flies are primarily a nuisance, although in some parts of the world they carry disease. They are not a major disease factor in the northern U.S.
ELSTON: The American Academy of Pediatrics recommends that DEET be used in a concentration of 10% or less for children, and many of these products are available. There is also a product called Bite Blocker, which is soybean-oil based, for parents who are concerned about using chemicals.
MEMBER QUESTION: Does Skin So Soft work as a repellant?
ELSTON: Skin So Soft, the original product, is a bath oil, which works primarily by having the insect wings caught in the sticky film. There's a Skin So Soft repellant marketed that contains different agents such as citronella oil. These products have not been as effective as other alternatives in some published studies.
MEMBER QUESTION: Is there ever any danger of sunscreen and insect repellant reacting with each other, or at the very least reducing the effectiveness of each other?
ELSTON: Yes. There was a paper published that shows that insect repellants decrease the effectiveness of sunscreens, but there are not many combination products on the market and it's best to use one of the combination products, because they've been stabilized.
|"If a tick is removed within 24 hours there is very little risk of Rocky Mountain spotted fever or Lyme disease."|
MEMBER QUESTION: What's the youngest age recommended for use of DEET products?
ELSTON: Check the products' labels, and for children in general the concentration of each should not exceed 10%.
MEMBER QUESTION: Are allergies to bee stings hereditary? My grandmother was highly allergic and I've never been stung. Should I be concerned?
MEMBER QUESTION: I was stung near my right eye by a honeybee when I was 11 years old. My face swelled up almost immediately and the swelling eventually spread to my neck. I was almost unrecognizable and my right eye was swelled tightly shut for days (my father had to pry the eyelids apart to get eye drops into it. It took about two weeks for the swelling to subside. I am 44 years old now and have not been stung by a honeybee since that time. I was stung by two yellow jackets a couple of years ago, on my right ear and under the left side of my jaw. My ear, face, and neck swelled up and my entire ear turned bright red. I felt like I had some tightness in my chest and was worried that it might be a severe reaction, so I went straight to my doctor. I had swelling for a few days and then it cleared up, but came back off and on for almost a year -- the red ear, swelling, and hives on my face. I am now very worried about being stung by insects again, particularly yellow jackets and honeybees. I've heard that reactions can get worse with repeat stings. I am an "outdoor" person and frequently find myself in areas where flying insects are around. I am wondering if I need to carry prescription antihistamine treatment?
ELSTON: You may need to carry a bee sting kit, antihistamine, and also consult an allergist. Desensitization shots are available and should be discussed with an allergist.
ELSTON: The tick should be removed promptly. The risk of infection rises the longer the tick is attached. If a tick is removed within 24 hours there is very little risk of Rocky Mountain spotted fever or Lyme disease. The tick should be removed without squeezing the body of the tick, by grasping the tick in the region of the head and pulling gently. There are several tick removal devices, such as the Tick Nipper, that are marketed to make the removal easier. Hands should be washed after tick removal.
MEMBER QUESTION: Are there any times of day that are worse than others for insect bites?
ELSTON: It depends on the insect. Mosquitoes in most regions feed at night, although in southern states there are day-feeding mosquitoes, as well. So that largely depends on the local area.
MEMBER QUESTION: Can your friendly neighborhood dermatologist tell what kind of bite/sting you have if you're not sure what 'got' you? On the other hand, does it help to know what kind of bite/sting you have if you aren't having an allergic reaction?
ELSTON: Sometimes the pattern of the bite will indicate what the arthropod was. Even in the absence of an allergic reaction, knowing what bit you may be important to predict what infectious disease you may be at risk for.
ELSTON: Some spider bites may be associated with staph bacterial infection, but other than that they are not major vectors of disease, other than rare cases of bacterial or fungal infection.
|"Even in the absence of an allergic reaction, knowing what bit you may be important to predict what infectious disease you may be at risk for."|
MEMBER QUESTION: What about fire ants? They can get very bad. What can you do about their bites?
ELSTON: If you are allergic to fire ant bites you should consult an allergist. The bite itself is a sting, which can be treated with a potent topical steroid prescribed by a physician. Control of fire ants can be accomplished by using various products, such as fire ant baits. Amdro is a popular one.
MEMBER QUESTION: When my wife and I go camping she gets eaten alive by mosquitoes and I do not have one bite on me. Can you give me an answer?
ELSTON: There are a number of factors, to include body temperature and how much carbon dioxide an individual produces that attracts the insect. So it does vary from one person to another.
ELSTON: Most fleas come from an associated pet, and the best way to prevent it is to treat the pet. A vet should be consulted, and a number of products, including fipronil and lufeneron products, can be prescribed by the vet for the pet. In some areas of the country, especially the Southwest, fleas do carry diseases such as plague and endemic typhus.
MODERATOR: Dr. Elston, do you have any final words for us?
ELSTON: Your local health department or the Centers for Disease Control are good sources of information for disease vectors in your area. For those camping or hunting, DEET or permethrin clothing or camping material can help prevent disease.
MODERATOR: Thanks to Dirk Elston, MD, for sharing his experience and expertise with us today. For more information please be sure to visit our message boards to talk with others and ask questions of our in-house experts. You'll be welcomed warmly!
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