FACTS
ABOUT LYME DISEASE IN CALIFORNIA
SYMPTOMS
Early
symptoms include a characteristic spreading rash accompanied by flu-like
symptoms, fever and aches. Possible complications in the heart and/or nervous
system may occur as well as severe arthritis. The disease commonly has these
three stages:
a
characteristic rash, known
as erythema migrans (EM), which occurs 3 to 30 days after the bite of an
infected tick.
EM is a red, blotchy, circular, expanding rash that may grow to several inches in diameter and clears centrally, producing a
ring-like appearance. One or more
EM lesions may occur, not necessarily at the bite site. EM may be preceded or accompanied by
flu-like symptoms. These symptoms may persist, change, disappear and
reappear intermittently for several weeks.
STAGE
2 - Some infected persons may develop long-term complications weeks to
months after the initial symptoms. These complications may include disorders of
the heart or nervous system. Abnormalities of the heart include varying degrees
of blockage in the heart muscle. Nervous system abnormalities include
meningitis, encephalitis, facial paralysis (Bell’s palsy) and other conditions
involving peripheral nerves. During this stage, patients may experience
migratory pain in joints, tendons, muscles, and bones, often without joint
swelling or redness.
STAGE
3 - Months to years after disease onset, patients may develop arthritis
that appears and disappears intermittently for several years. Arthritis is the
most common long-term symptom of Lyme disease. Large joints, especially the
knees, are most often affected. Lyme arthritis may become chronic, with erosion
of cartilage and bone.
THE
VECTOR OF LYME DISEASE IN CALIFORNIA
The Western Black-legged Tick (Ixodes pacificus) is the only tick of the 49 species in California that is known to transmit Lyme disease. The spirochete causing Lyme disease was first isolated from this tick in 1984.
The tick has three active life stages. Immature stages (larvae and nymphs) feed on small rodents, rabbits, lizards, birds, and occasionally large mammals. Adults feed on large mammals, including deer, dogs, and humans. All stages feed by imbedding their mouthparts into the skin of a host and taking a blood meal.
Preliminary studies show that white-footed mice and deer
may be the primary reservoirs of Lyme disease
in California. Larval and nymphal ticks acquire spirochetes from
the blood of infected mammals as
they feed; the infected nymphs and
adults transmit the spirochetes to other mammals (including humans). In
California a low percentage of the ticks tested are infected with the Lyme
disease spirochete.
Adult
ticks are most commonly found from December through June, during the period of
the year when humidity is usually high. The adult female is red-brown and black
legs, about 1/8 of an inch long. Males are smaller and entirely brownish-black.
Both are teardrop shaped. This tick can be found on grasses and brush in both
urban and rural settings. Ticks do not fly, jump, or drop from trees. Instead
they climb to the tips of vegetation, typically along animal trails or paths,
and wait for a host to brush against them. This behavioral method of finding a
host is called questing.
WHAT
TO DO IF YOU THINK YOU HAVE LYME DISEASE
Early recognition of Lyme disease is important. If you have found a tick attached to your skin or if you were in an area where ticks are known to occur and if you have any of the symptoms listed above, tell your physician immediately of your suspicions. This information, together with a blood test, will help your physician make a diagnosis. Treatment with antibiotics during the early stages can cure the infection and prevent complications associated with stages 2 and 3.
For more information about ticks click here.
For More Information:
(530) 365-3768
The information in this web page is also available in a brochure.