In recent months, two of my associates have been hit by vector-borne illnesses, which are caused by the transmission of microorganisms from an infected host.

They are fairly common across the country in the summer and fall as people start to spend more time outdoors.

Lyme disease is the most common vector-borne illness. Bees, wasps, mosquitoes, spiders and snakes make up the rest of the vector-borne illnesses.

Lyme diseased was named in 1977 when arthritis was observed in a cluster of children in and around Lyme, Conn. Currently there are about 20,000 cases of Lyme disease reported to the Centers for Disease Control each year.

The ticks that carry the disease are found throughout the United States, but are more heavily concentrated in the Northeastern U.S. including Pennsylvania. These ticks are especially heavy in wooded areas, which abound in our state.

The bacterium Borrella burgdorferi is associated with Lyme disease. It is carried by the black-legged tick, commonly known as the deer tick. The immature ticks become infected by feeding on small rodents, such as the white-footed mouse, that are infected by the bacterium. The chain of carriers ends there as Lyme disease is not transmitted from person to person.

A bite from an infected tick does not automatically result in Lyme disease. Studies have shown that the longer a tick is attached to you the greater the chance the disease will be transmitted.

Transmission is unlikely if the tick attachment is under 24 hours. Although ticks bite year-round, the peak tick season is summer and early fall, when most people are camping and trekking through the woods.

Archery hunters are commonly in contact with tick-infested areas, as they do their early season scouting for deer hunting.

The key to maintaining your health, as well as your activities, is to use prevention, detection and treatment if necessary for tick bites.

Currently, the best prevention against Lyme disease is to limit activities in woody, brushy or grassy areas, which have high tick activity. Bug repellent, long sleeves, long pants and tight wrist and ankle areas can help.

A tick check should be done after every excursion, with special attention to the scalp area. Immediate removal of any tick is essential. A safe method is to use tweezers. Grasp the tick as close to the skin as possible and pull straight out. Do not try to irritate the tick with heat or chemicals or especially do not squeeze the tick's body. This may cause the tick to inject more germs into the skin. Wash the area with antibacterial soap and warm water after removal.

Diagnosis of Lyme disease can be difficult if you are not aware of a tick bite. A rash or red bull's eye or flu-like symptoms may tip you off to the need for treatment.

The goal of treatment is to minimize symptoms and to halt progression of the illness. Antibiotic treatment is generally effective in the early stages of the disease, and a 14- to 21-day course of oral antibiotics often clears the infection.