Signs and Symptoms
Although mosquito bites are quite common among the general population, allergies to mosquito bites are luckily rather rare. Most individuals experience localized itching, swelling, and/or redness of the skin at the site of the bite. However, if someone is allergic to the mosquito, they may have more severe skin reactions which can include extremely large areas of swelling and redness, blistering, and/or bruising. In rare cases, some individuals may experience anaphylaxis (a severe life-threatening systemic reaction) after a mosquito bite. Such individuals experience symptoms which may include some or all of the following:
1. Throat closing sensation
2. Hives (Urticaria)
3. Generalized itching of the skin
4. Drop in blood pressure
5. Shortness of breath and/or wheezing
6. Dizziness, lightheadedness, and/or fainting
7. Abdominal cramping, nausea, vomiting, and/or diarrhea
8. Rapid and weak pulse
9. Feeling of warmth
Mosquitoes are flying insects that tend to be more prevalent where there is standing water. They are more active early in the morning and early in the evening. Female mosquitoes lay their eggs in stagnant water. Only the female mosquito bites and feeds on human blood, as they need this blood in order to produce their eggs. Male mosquitoes feed on water and nectar. When a person is bitten, the mosquito injects its saliva into the skin which contains proteins that prevent the human blood from clotting. This allows the blood to be transferred to the mosquito’s mouth. The typical localized itching, swelling, and/or redness of the skin that results from the bite is not directly due to the bite itself, but rather caused by the body’s immune response to the proteins in the mosquito’s saliva. An “allergic reaction” to a mosquito bite is defined when there is a severe immune reaction against the salivary proteins of the mosquito, thus causing the more severe symptoms mentioned above.
Diseases Transmitted by Mosquitoes
In addition to causing allergies in selected individuals, mosquitoes are well known for transmitting many infectious diseases such as dengue fever, malaria, West Nile virus, filariasis (elephantiasis), yellow fever, chikungunya, Eastern equine encephalitis, Western equine encephalitis, Venezuelan equine encephalitis, Japanese encephalitis, St. Louis encephalitis, La Crosse encephalitis, Rift Valley fever, Ross River fever, and Zika fever.
Mosquitoes are attracted to certain people more than others for a variety of reasons. They are more attracted to individuals with the following characteristics: Type O blood, males, obese or overweight people due to increased carbon dioxide (CO 2) levels, specific body odors that are present because of large numbers of certain bacteria, people wearing dark clothing, individuals that are exercising, and increased body heat.
Diagnosis, Prevention, and Treatment
The diagnosis of mosquito allergy can be done via a blood or skin test and is only done in individuals that have had severe reactions that can be ascertained after a thorough history from the patient. Prevention, however, is the key to treatment. One should avoid areas with standing water such as swamps or fresh water reservoirs. Wear light colored long sleeved clothing and hats. Consider wearing permethrin-treated clothing. Use citronella-scented candles when at outdoor events. Use a bed net if sleeping outdoors. Stay in screened in or air conditioned rooms. Apply insect repellent that preferably contains a 10-25% concentration of DEET (N,N-diethyl-3-methyl-benzamide or N,N- diethyl-meta-toluamide). One can alternatively use insect repellents containing either picaridin or oil of lemon eucalyptus.
Besides prevention, the treatment of mosquito bites is aimed at treating the symptoms of the bite. Since most mosquito bites cause only a local reaction, various topical medications can be used which can include calamine lotion, corticosteroid creams, anti-itch creams, and/or topical antihistamines. It may also be advantageous to apply ice or a cold pack to the site of the local reaction. Oral antihistamines may offer more relief in certain individuals. In the cases where anaphylaxis occurs, the individual should use a self-injectable epinephrine device (i.e., EpiPen, Auvi-Q, Adrenaclick), call 911, and go immediately to the closest emergency room. Fortunately, anaphylaxis is quite rare when it comes to mosquito bite allergies, however, it is a possibility and anyone who has symptoms of mosquito bite allergy should see a board certified allergist.
The board certified allergists at Black & Kletz Allergy have been serving the Washington, DC, Northern Virginia, and Maryland metropolitan area for over 5 decades and have office locations in Washington, DC, McLean, VA (Tysons Corner, VA), and Manassas, VA with on-site parking. The Washington, DC and McLean, VA office locations are also Metro accessible. Please call us for an appointment or alternatively, you can click Request an Appointment and we will get back in touch with you within 24 hours of the next business day. Black & Kletz Allergy prides itself in providing quality allergy care to both adults and children in a friendly professional environment.