Insect and Spider Bites and Stings

Insect bites and stings are a fact of life if you spend time outdoors. Fortunately, although they may be painful, they usually aren't serious. Unfortunately, some bites and stings are poisonous or can cause serious allergic reactions or infections. Most sting reactions are caused by five types of insect: yellow jackets, honey bees, wasps, hornets, and fire ants. Here's what you should know about treating bites and stings from these pests, as well as from spiders and ticks.

Stings from bees, wasps, and hornets

Most bee and wasp stings are not serious. A minor sting can be painful and sometimes cause a little swelling, redness, burning, or itching at the site of the sting. However, if you have an allergic reaction to stings, or if you're stung multiple times by a swarm, they can be life-threatening.

What to do

Move to a safe area to avoid getting stung repeatedly. Hornets, wasps, yellow jackets, and ants do not leave their stingers, but bees can. If any part of the stinger remains, scrape it out immediately with your fingernail or the edge of a credit card. Do not push on the stinger, or you may squeeze more poison into the wound. Wash the affected area with soap and water, then apply ice or a cold pack to reduce pain and swelling. Other treatments for mild insect stings:

• Elevate the arm or leg. (However, with venomous spider and scorpion bites, do not raise the site of the bite above the level of the victim's heart.)
• Apply a cold compress.
• Use topical steroid ointments or oral antihistamines to relieve itching if needed. Apply a 1 percent hydrocortisone ointment, which is available over the counter, if the itching is significant. An antihistamine such as diphenhydramine (Benadryl), also available over the counter, may also help.

Remember to seek immediate medical attention if the sting gets infected or if the swelling doesn't subside or progresses. When stings cause severe allergic reactions, they can be dangerous, even life-threatening. The severity of the reaction depends on how sensitive a person is to insect venom. Symptoms of severe insect sting allergies include:

• Rapid swelling of the eyes, lips, tongue, or throat
• Difficulty breathing
• Severe itching
• Hives
• Nausea or vomiting
• Muscle or stomach cramps
• Numbness
• Reddish rash
• Headache
• Dizziness, confusion, or loss of consciousness
• Diarrhea

If any of these symptoms develop, call 911 or go to an emergency facility immediately. While waiting for help to arrive, take the following steps:

• Have the person lie down. If the victim is unconscious but breathing, turn the person onto her side, positioning the head to one side to prevent choking on any liquids that may be in the mouth. If the person is not breathing and does not have a pulse, begin cardiopulmonary resuscitation (CPR) immediately.
• Check to see if the victim is carrying an allergy kit containing epinephrine, a form of adrenaline that is used to prevent a life-threatening allergic reaction. If so, follow the directions in the kit.

People with a history of severe allergic reactions to insect bites should be prepared if they exercise outdoors or travel to areas with lots of stinging insects. Many people who have severe allergic reactions carry injectable epinephrine pens that provide short-term treatment for severe allergic reactions. They must still seek emergency attention.

People with diabetes and others with circulation problems may be at risk for complications and infections after being stung. They should seek immediate medical attention.

Spiders

Although there are many kinds of spiders, only a few are dangerous to people. Two of concern in the continental United States are the black widow and brown recluse spiders. Both tend to live in dry, out-of-the-way areas such as under sinks, in closets, in basements, or in woodpiles. They are especially common in the southern United States.

Black widows, which can be either black or brown, have a red, hourglass-shaped spot on the abdomen, and their bite leaves a faint red mark.

Brown recluse (or fiddleback) spiders are identified by a brown, violin-shaped mark on the back. Their bite produces a bull's-eye pattern of red circles accompanied by blistering and swelling.

What to look for

A bite from one of these spiders may feel like nothing more than a pinprick. Some people don't even realize at first that they have been bitten. Within a few hours, however, the bite area begins to swell and becomes intensely painful. A blister forms over the bite of a brown recluse spider. Other signs and symptoms include:

• Nausea, vomiting, fever, or chills
• Difficulty breathing or swallowing
• Excessive sweating and saliva

What to do

Wash the bite area with soap and water. Apply a cold cloth or ice pack to reduce swelling.

Call your doctor immediately. If he or she is not available, call 911 or go to the nearest emergency facility. If possible, bring the spider for identification. For black widow bites, doctors may recommend an anti-venom medication. For brown recluse bites, treatment may include a corticosteroid medication to reduce the body's reaction to the venom.

Do not give the victim aspirin, stimulants, or pain medication unless you are instructed to do so by a doctor.

Tick bites

Tick bites may not leave a raised site, but they are worrisome because ticks can transmit diseases, including Lyme disease, Rocky Mountain spotted fever, ehrlichiosis, and tularemia. These diseases can be dangerous, so it's important to remove ticks as soon as possible and then monitor the bite for signs of infection. The sooner you remove a tick, the less risk of infection.

When they first attach themselves to the skin, some ticks are no bigger than the period at the end of this sentence. As they begin ingesting blood, they can then grow many times their original size.

What to do

First, always check for ticks after you have been out in the woods. Thoroughly examine your skin and scalp. If you go hiking with children, examine them carefully, including their clothing. Sometimes you can find and remove ticks before they can attach.

Although the American Red Cross used to suggest suffocating the tick by covering it with petroleum jelly, mineral oil, or some other heavy oil, these and other home remedies (like applying fingernail polish or a hot match) don't work. In fact, according to the American Medical Association, these sorts of remedies can make things worse by causing further harm to your skin or by pushing the tick further in.

Experts agree that if a tick has attached itself, the best way to remove it is by gently pulling it out with tweezers. Using tweezers, grasp the bug as close to the skin as you can. Slowly lift it away from the skin. Be careful not to jerk or twist the tweezers, because this can break off the tick's head and lead to infection. If you don't have tweezers, you can remove very small ticks with the edge of a credit card. (For larger ticks, use your fingers.)

If part of the tick remains behind, don't panic. Sterilize a needle by dipping it in rubbing alcohol, then use it to get the rest of the tick out, the way you would pull out the remains of a wood splinter. If you can't remove the tick completely, call your doctor.

If you live in an area where ticks carry disease, it's wise to save the tick in alcohol. That way, it can be tested if you develop symptoms.

After the tick is removed, wash the area carefully with soap and water. Then watch out for any unusual signs or symptoms, including:

• A rash at the site of the bite, especially a red "bull's-eye" rash -- this is a classic symptom of Lyme disease
• Flu-like symptoms such as fever, fatigue, headache, muscle aches, and joint pain.

Call your doctor if you develop any of these signs and symptoms. Tick-borne infections can be treated with antibiotics.

References

American Medical Association. Handbook of First Aid and Emergency Care.

American College of Emergency Physicians. First Aid Manual.

The American Red Cross First Aid & Safety Handboook.

MayoClinic.com. Spider Bites: First Aid.

American Academy of Allergy Asthma & Immunology. Tips to Remember: Stinging Insect Allergy. http://www.aaaai.org/patients/publicedmat/tips/stinginginsect.stm

EMedicinehealth.com. Wilderness: Black Widow and Recluse Spider Bites. http://www.emedicinehealth.com/articles/27039-4.asp

Elston DM. Insect Bites. EMedicine.com. http://www.emedicine.com/derm/topic467.htm

American Red Cross. How to Treat Insect Bites and Stings. http://www.redcross.org/email/safetynet/v1n9/buzz.asp