The bacteria that cause ehrlichiosis are carried by certain kinds of ticks and can be transmitted to a person when a tick bites them. In the south central U.S., the lone star tick (
) is known to carry and transmit the agent of ehrlichiosis. The tick vector in California has not been identified.
Taking appropriate precautions to avoid tick bites can reduce the risk of infection with ehrlichiosis, as well as other diseases transmitted by ticks. When you are in areas where ticks are present:
• Stay on trails whenever possible.
• Apply repellents containing DEET to the skin.
• Apply tick repellents containing permethrin to your clothing.
• Check yourself for ticks promptly after being in an area where ticks are present.
• Remove any ticks you find on your body right away.