Thus far this year, 20 cases have been reported, which surpasses the previous record number of 19 cases reported in the county in 2011.
"Ticks can transmit a number of serious illnesses, including Lyme disease, through a bite," said the health department's executive director Tony Beltran. "They live in and near wooded areas, tall grass and brush, so it is important to use prevention measures including insect repellent when you are in such an environment, even if it is your own backyard."
Here are some prevention measures to take against ticks:
Keep your grass mowed around your home and near playground equipment.
Install a wood chip or gravel barrier between lawns and wooded or tall grass areas.
Do not brush against plants outdoors and walk in the center of paths through parks and forest preserves.
Minimize wood piles attractive to small animals that can carry ticks.
Wear light-colored, protective clothing such as long-sleeved shirts, long pants, boots or sturdy shoes and a head covering.
Tuck pant cuffs in socks and tuck in shirt tails.
Apply insect repellent containing DEET (30 percent or less) to clothes or exposed skin (except the face). Wash treated skin after coming indoors and supervise children while using repellents.
Check your pets for ticks if they go outdoors. When checking for ticks, pay extra attention to the hair, the neck, behind the ears and the groin.
Remove ticks with a tweezers by grabbing the head of the insect closest to the skin and pulling upward with slow, even pressure. Do not squeeze the tick's body. Do not twist or pull the tick quickly as the mouth parts could break off and remain in the skin.
Symptoms of Lyme disease may include "bull's-eye" rashes or lesions around the site of the bite (generally seven to 14 days after the tick has consumed a blood meal), accompanied by flu-like symptoms such as fever, fatigue, headache, muscle aches, and/or joint aches. The disease is brought on by a bacterium called Borrelia burgdorferi that is transmitted by a deer tick that attaches to a human's skin.
Lyme disease can be treated with antibiotics, but typically goes under-reported because instead of the tell-tale rash, individuals may experience only the flu-like symptoms. If you experience any of these symptoms seven days or more after a tick bite, you should contact your physician. Left untreated, the illness can spread to the musculoskeletal system, heart and nervous system. Lyme disease cannot be passed from person-to-person. The likelihood of contracting Lyme disease is small if a deer tick is attached for less than 36 hours.
New Lyme disease estimate: 300,000 cases a year
As many as 300,000 Americans are actually diagnosed with Lyme disease each year, the Centers for Disease Control and Prevention announced.
Usually, only 20,000 to 30,000 illnesses are reported each year. For many years, CDC officials have known that many doctors don't report every case and that the true count was probably much higher.
The new figure is the CDC's most comprehensive attempt at a better estimate. The number comes from a survey of seven national laboratories, a national patient survey and a review of insurance information.
"It's giving us a fuller picture and it's not a pleasing one," said Dr. Paul Mead, who oversees the agency's tracking of Lyme disease.
The ailment is named after Lyme, Conn., where the illness was first identified in 1975. It's a bacteria transmitted through the bites of infected deer ticks, which can be about the size of a poppy seed.
Symptoms include a fever, headache and fatigue and sometimes a telltale rash that looks like a bull's-eye centered on the tick bite. Most people recover with antibiotics. If left untreated, the infection can cause arthritis and more severe problems.
In the U.S., the majority of Lyme disease reports have come from 13 states: Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Vermont, Virginia and Wisconsin.
The new study did not find anything to suggest the disease is more geographically widespread, Mead said.
The Associated Press contributed to this report.