Lyme disease, a bacterial infection spread by tick bites, has tripled in the United States since the 1990’s and researchers say it is partly due to an expansion of the parts of the US where ticks can be found.

An article on Fox News says that disease-carrying ticks now live in almost half of all US counties, up from 30 percent in 1998, according to a new study from the Centers for Disease Control and Prevention (CDC).

Ticks, usually found in wooded and grassy areas, carry the disease to humans by attaching themselves to the body, and experts caution parents to check their children carefully after they have been outside in these types of surroundings.  Lyme disease can be treated by antibiotics if caught early, but can lead to joint and muscle pain, mood disorders and even lasting cognitive issues, if not treated.  Symptoms include fever, headache and fatigue and are sometimes confused with the flu virus.  Many patients will develop a “bull’s eye” rash following a tick bite, but not in all cases.

Deer ticks and western blacklegged ticks are the main carriers of Lyme disease.  Data reported from 3,110 counties in the continental US revealed the presence of ticks in about 46 percent of the nation’s counties, up 45 percent from 1998 when only 1,058 counties reported tick populations.  Deer ticks are now established in 35 states, up from 32 in 1998, and were formerly concentrated in the northeast, but have begun to migrate to the south and west.  Western blacklegged ticks are primarily found in the Pacific coast states, with populations established in six states.

To prevent being bitten by ticks, experts recommend using an insect repellent, like DEET or lemon permethrin, and also wearing long sleeves and keeping your pant legs tuck in your socks or boots.  They also advise having a family member check for ticks as well as keeping a check on pets that are allowed outside.

Not all areas have the same risk of infection with Lyme disease, since the number of ticks infected with the bacteria varies, lowering the odds.  Warmer and wetter winters increase the chances of tick survival, and lead to increases in the populations.