( CNN ) -- The blacklegged ticks are out , and they 're infecting hundreds of thousands of Americans with a bacterial illness -- more often than experts previously thought . About 300,000 Americans each year are diagnosed with Lyme disease , according to new estimate released by the Centers for Disease Control and Prevention this week . That number is 10 times higher than the number of cases reported annually to the CDC . The latest estimates were presented at the 2013 International Conference on Lyme Borreliosis and Other Tick-Borne Diseases on August 18 . `` This new preliminary estimate confirms that Lyme disease is a tremendous public health problem in the United States , and clearly highlights the urgent need for prevention , '' said Dr. Paul Mead , chief of epidemiology and surveillance for the CDC 's Lyme disease program , in a statement . Lyme disease , which comes from a bacterium called Borrelia burgdorferi , is the most common illness spread by ticks in North America and Europe , according to the Mayo Clinic . Blacklegged ticks can spread such bacteria while feeding on the blood of animals and humans . Most humans are infected by immature ticks called nymphs , the CDC says , which generally feed during the spring and summer months . Ticks carrying this disease hang out in grassy and heavily wooded areas . Patients who take appropriate antibiotics early on in the disease are likely to make a full recovery , according to the Mayo Clinic . It may take longer to respond to treatment in later stages of Lyme disease , but , with appropriate treatment , most people recover completely . Why you should be afraid of Lyme disease . Symptoms . Fever , headache , fatigue and a rash called erythema migrans are all typical symptoms of Lyme disease . This rash often resembles a bull 's eye and can appear within a few days of infection . Between 70 % and 80 % of people with Lyme disease develop this rash , and some patients develop it at more than one location on their bodies . Left untreated , the Lyme disease infection can spread to the joints , heart and nervous system , according to the CDC . This can lead to joint pain and swelling . After several weeks to months , patients may also experience swelling of the membranes surrounding the brain , temporary paralysis of one side of the face and `` brain fog '' : forgetfulness or confusion . What to do if you get bitten . Ticks can be tiny : Deer ticks may be as small as the head of a pin , so look for them carefully . Removing a tick within 24 hours cuts your risk of developing Lyme disease because it takes time for the bacteria to move from the tick to the host . The longer the tick is attached to the human body , the more likely that person will be infected . Use tweezers to carefully and steadily pull the tick off , grasping near its mouth or neck . Then put antiseptic on the infected area . Contact your doctor immediately if you 've been bitten by a tick and start to experience symptoms . Even if your symptoms disappear , you should still see a doctor . Treatment . The standard treatment for Lyme disease in early stages is oral antibiotics . Usually , a 14- to 21-day course is recommended , but some studies suggest that a 10- to 14-day course is equally effective , according to the Mayo Clinic . If the central nervous system has been affected by the disease , intravenous antibiotics may be given for 14 to 28 days . This treatment eliminates the infection , but you may need more time to recover from symptoms . The side effects from this treatment may include a lower white blood cell count , diarrhea or infection with other organisms resistant to antibiotics that are unrelated to Lyme disease . Prevention . The CDC recommends wearing insect repellent with at least a 20 % DEET concentration and avoiding wooded areas with high grass areas where ticks are most often found . It also suggests checking for ticks daily and showering soon after being outdoors . Using a washcloth while bathing may remove any unattached ticks lingering on the skin . Covering yourself outdoors can also help : Wear shoes , long pants , long-sleeved shirt , hat and gloves in wooded or grassy areas , says the Mayo Clinic . Your pets can also bring ticks into the house , so check them regularly . More facts about ticks . These arachnids ca n't fly or jump but rather wait for a host -- whether it be a mammal , bird , reptile or amphibian -- to feed on while resting on the tips of grasses and shrubs . They hold on to leaves and grass with their lower legs , a position called `` questing . '' As the host passes by , the tick climbs on and finds a place to bite . Besides Lyme disease , ticks can also transmit other illnesses such as babesiosis and Colorado tick fever . Make it your quest to stay safe . Buzz off , bugs ! How to stay safe during insect season .
Lyme disease results from a fungus called Borrelia burgdorferi . It 's the most common illness spread by ticks in North America and Europe . Most people recover completely with appropriate treatment .