Insect bites and stings can be unpleasant, painful and, for some, deadly. Travelers can have histamine reactions when stung or bitten which can deteriorate quickly into respiratory or cardiac collapse, life-threatening conditions. A variety of diseases can be spread by the bites of infected mosquitoes, such as West Nile, malaria and dengue.

Symptoms of an insect bite result when the venom enters the skin, sometimes triggering an allergic reaction. The severity of the reaction depends on sensitivity to the toxin and recent or cumulative exposure.

Most reactions to insect bites are mild, with an annoying itch or stinging sensation and mild swelling, and disappear in a day or two. Delayed reactions include fever, hives, painful joints or swollen glands. The same bite or sting can cause both types of reaction. Only a small percentage of people develop severe reactions, with symptoms including nausea, facial swelling, difficulty breathing, abdominal pain and decreased blood pressure leading to cardiovascular and pulmonary collapse.

For mild reactions, move to a safe area to avoid more stings. Remove the stinger. Sweep the edge of a credit card across the site — do not use tweezers, which may release more venom into the tissue. Apply an ice pack to reduce pain and swelling. Apply cortisone cream, calamine lotion or a paste of baking soda and water several times a day. Take an over-the-counter antihistamine, such as Benadryl (diphenhydramine).

If you experience a more severe allergic reaction, contact your health care provider immediately. Call for emergency medical assistance if you have difficulty breathing, swelling of the lips or throat, dizziness, confusion, a rapid heartbeat, hives, nausea, cramps or vomiting.

While waiting for medical care for yourself or while assisting someone else, try the following: If the victim carries medications to treat an allergic reaction, such as an EpiPen, give as directed. Administer an antihistamine pill if the person is conscious and able to swallow without choking. Have the person lie still on his back and elevate the legs above the head; loosen tight clothing and, if possible, cover him with a blanket. Do not give anything to drink. If the victim begins to choke or vomit, turn him on his side. Begin CPR if there are no signs of circulation.

Although rare, some insects carry diseases. West Nile virus affects mostly birds, but mosquitoes can spread it to people. It produces flu-like symptoms such as fever, headache, body ache and skin rash. There is no specific treatment, and in some cases, the virus leads to serious problems such as encephalitis (inflammation of the brain) or meningitis (inflammation of the membranes and fluid around the brain and spinal cord).

Tick-borne germs are passed to humans from the bite of ticks infected with bacteria, viruses or parasites. Lyme disease, a bacterial infection (Borrelia burgdorferi) that produces a skin rash, swollen joints, headache, muscle pain and flu-like symptoms, is the most common tick-borne disease in the United States. A tick must remain attached for at least 24 hours for infection to occur. Antibiotics usually cure early-stage Lyme disease; but, untreated, it can lead to chronic problems with the joints, the heart and nervous system and is quite serious in advanced stages. If you find a tick on you, try to carefully remove it with tweezers by grasping the tick near its head and pulling without twisting. If you cannot easily dislodge the tick, get immediate medical care. For more information, visit www.cdc.gov.

Pest Protection

• Use EPA-registered insect repellents on exposed skin (those containing DEET and picaridin) and be aware of their length of effectiveness.

• Use DEET formulations as high as 50 percent for adults and children over 2 months of age. Protect younger infants by using a carrier draped with mosquito netting and secured with an elastic edge.

• Apply sunscreen first, then repellent. Wash off at the end of the day.

• Wear long-sleeved shirts tucked in, long pants and hats. Wear boots and tuck pants into socks.

• Inspect yourself for ticks outdoors and at the end of the day. Ticks are more apparent on light-colored clothing.

• Apply permethrin-containing repellents to clothing but not to skin. Launder treated clothing separately.

• Mosquitoes that transmit malaria are most active at twilight. Stay in air-conditioned or well-screened housing and sleep under an insecticide-treated bed net.

• Take special care when camping or staying in rustic accommodations.

• Shake out clothing and shoes before putting them on.

The content of this article is for informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition.