The Small Things that Bite

By Michael J. Smith, MD, FAAP
Internal Medicine & Pediatrics
Southside Medical Clinic, Eau Claire

It’s summer and we find ourselves hassled by biting insects. Of course, we think first of mosquitoes and ticks. Traditionally, these were felt to be more of a nuisance than a problem, but this situation is changing with the increasing reports of West Nile virus (a disease transmitted by mosquito bites), and Lyme disease (a disease transmitted by ticks).

Physicians are frequently asked to suggest the best insect repellents. The most effective ingredient found in repellents today is a compound known as DEET. DEET has been used as a repellent for over 45 years; carries a long history of safety information and can be found in a variety of concentrations. Concentrations in the range of 10-35% are very effective at preventing mosquito bites. When this repellent is used for children, the concentration of DEET that is applied to the child should not exceed 10%. DEET does not need to be applied directly to the skin to be effective and therefore higher concentrations can be use to spray clothing or other items.

There are other insect repellent products available, but none has been proven to be as effective as DEET (see table). One should not forget the importance of using other methods for avoiding mosquito bites including wearing loose fitting clothing, using mosquito netting and avoiding areas that have high mosquito populations.

The majority of us will receive mosquito bites this summer and we have an increasing concern regarding a mosquito born illness, West Nile disease. Fortunately, West Nile virus remains a rare condition. Four out of five of those who do receive a bite containing the West Nile virus will not develop any type of illness. The symptoms one might experience, if they do acquire the West Nile virus and infection, include headache, high fever, stiff neck, disorientation or other neurologic symptoms. Of the one in five persons who get the West Nile virus and subsequently report the above symptoms, only one in 150 will develop a serious illness. More serious infections may occur in individuals of advanced age, or those who have weaker immune systems.

Ticks are also a concern during the summer. The larger wood tick does not carry Lyme disease. The small deer tick potentially carries Lyme disease and a lesser known illness, ehrlichiosis. Lyme disease is frequently diagnosed during the summer with symptoms including fever, aching muscles, fatigue or arthritis-type complaints. Frequently, a red rash is seen with Lyme's infection, although the infection can occur without this. It is believed that a person needs prolonged exposure to the tick to receive the organism that causes Lyme disease. Therefore, daily “tick checks” when dressing and undressing are recommended. If a tick is found, the best way to remove it is to grasp it firmly and pull directly off. If any symptoms develop, one should contact their physician for further evaluation and potential treatment.

By avoiding insects through the proper use of clothing, netting and insect repellents, one can have an itch-free and happy summer. If on the other hand, any of the above symptoms appear, a trip to your doctor may answer any questions you may have.

For more information, or to schedule an appointment with Dr. Smith » 715.830.9990 Southside Medical Clinic or visit www.southsidemedicalclinic.com