SACRAMENTO (April 17, 2007) – As warmer spring temperatures attract Californians to outdoor activities, people must take precautions to prevent tick bites because some ticks carry germs that cause disease, including Lyme disease, State Public Health Officer Dr. Mark Horton advised today.

Western black-legged ticks on a finger. Left to right: nymph, adult male, adult female. Source: California Department of Health Services.

"Californians should take measures to reduce their exposure to ticks when they venture outdoors to work in their yards and participate in recreational activities, including hiking and camping," Horton said.

Ticks are small, insect-like creatures that are often found in naturally vegetated areas throughout California.  They prefer cool, moist environments, shaded grasses, shrubs and leaf litter.  Ticks attach to animals and feed on their blood over several days.  

Individuals may become infected with the bacteria that cause Lyme disease when they are bitten by an infected western black-legged tick, the only tick in California that transmits Lyme disease.

The smaller, immature form of the tick known as a "nymph" is most active during the spring and early summer months and has already been detected this spring in Alameda, Santa Clara and Sonoma counties.  Roughly the size of a poppy seed, nymphs are found on logs, tree trunks, fallen branches or tree limbs and among the damp leaves that accumulate under trees.  Nymphs may attach to people as they gather or sit on logs or walk through leaf litter.  Because nymphs are so small, people may not notice if one attaches to them.

Early symptoms of Lyme disease often include a spreading rash, which is usually accompanied by flu-like symptoms, such as fever and body aches.  Prompt treatment with antibiotics can cure the disease, particularly when it is diagnosed early.  If left untreated, symptoms can progress into arthritis, heart ailments or nervous system disorders. 

Ticks in California can carry other germs that cause diseases in humans, such as anaplasmosis, babesiosis, ehrlichiosis and Rocky Mountain spotted fever.  The first line of defense against tick-borne diseases is taking proper personal protective measures to avoid tick bites.  Horton offered the following steps to reduce exposure to tick bites:

·    Avoid areas where ticks live, such as trail margins, brushy and grassy areas and leaf litter in forests with oak and other hardwood trees.  Stay on trails and avoid contact with logs, tree trunks and fallen branches or tree limbs in forests.

·    When in areas where ticks can be found:

o    Wear light-colored clothing so ticks can easily be seen.

o    Wear long pants and long-sleeved shirts.  Tuck pant legs into boots or socks and tuck shirts  into pants. 

o    Use a repellent registered for use against ticks.  Repellents with DEET are effective and can be applied to the skin.  Repellents with permethrin should be applied only to clothing.  Always follow directions on the container and be especially careful when applying to children. 

o    Inspect yourself frequently for ticks while in tick habitat

·     After outdoor activities in tick-infested areas:

o   Conduct a check of your entire body, especially the hairline, armpit, back of knees and groin, each day for up to three days after returning from tick habitat.  An additional tick check two or three days after exposure may reveal an engorged tick or a tick bite reaction that may not have been noticeable before.  Checking bed linens after being in tick-infested areas may also help identify an engorged tick that has completed feeding.

o   Parents should inspect their children, especially on the scalp and hairline, after activities in tick-infested areas.

Individuals who discover a tick attached to their body should remove it as soon as possible to reduce the possibility of infection.  The sooner a tick is removed, the less likely you are to get sick from an infected tick bite.  The tick should be removed by grasping it with fine-pointed tweezers and pulling it gently, but firmly, straight out.  Insecticides, lighted matches, petroleum jelly or gasoline are ineffective and should not be used to remove ticks.  Individuals are advised to wash their hands and apply antiseptic to the affected area.  Individuals who develop a rash, fever or other symptoms within two to four weeks after being bitten by a tick should consult their physician immediately.

Additional information is available on the California Department of Health Services' Web site at http://www.dhs.ca.gov/ps/dcdc/disb/disbindex.htm.

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