Tick-Borne Diseases


Tick-Borne Diseases


Lyme Disease

What is Lyme disease?

Lyme disease is caused by a bacteria (Borrelia burgdorferi) which is transmitted by ticks. It may be cured by early diagnosis and appropriate antibiotic treatment, but it may persist in the human body for years, if not properly treated. Lyme disease was named for Old Lyme, Connecticut, where the first cases of Lyme disease were reported. The first case in California was reported in 1978. It is currently the most commonly reported tick-borne disease in California, as well as in the United States.



What is Anaplasmosis?

Anaplasmosis is a disease caused by the bacteria Anaplasma phagocytophilum, transmitted to humans by tick bites.  It is less common than Lyme disease in California but is transmitted by the same tick, the western black-legged tick (Ixodes pacificus).  On the east coast of the United States, the tick vector is the deer tick (Ixodes scapularis).  It is treatable with antibiotics and rarely fatal.   A person who has been bitten by a tick and develops symptoms of Anapslasmosis should see their physician.

An identification diagram for Dermacentor variablis  ticks.


What is Tularemia?

Tularemia, rabbit or deerfly fever, is a relatively rare bacterial disease transmitted to humans and animals by the bite of ticks. It is much less common that Lyme disease in California and is primarily transmitted by summer ticks, the American dog tick (Dermacentor variablis). It may be cured by early diagnosis and appropriate antibiotic treatment.


Borrelia miyamotoi Infection

What is Borrelia miyamotoi infection?

Borrelia miyamotoi infection refers to a type of illness caused by the bacteria Borrelia miyamotoi carried by ticks.  In San Mateo County, the ticks that carry bacteria that cause this illness are Ixodes pacificus, the western black-legged tick.  It is closely related to the bacteria that causes tick-borne relapsing fever.  The infection is treatable with antibiotics.  A person who has been bitten by a tick and develops symptoms of Borrelia miyamotoi infection should see their


Rocky Mountain Spotted Fever

What is Rocky Mountain Spotted Fever?

Rocky Mountain Spotted Fever (RMSF) is a bacterial disease (Rickettsia rickettsii) transmitted by ticks of the genus Dermacentor. These ticks are most common during spring and summer. Rocky Mountain Spotted Fever is very rare in San Mateo County.

How is Rocky Mountain Spotted Fever transmitted?

RMSF is transmitted through the bite of an infected tick.