U.S. President George W. Bush was successfully treated for Lyme disease nearly a year ago, the White House said Wednesday.

The condition had never been revealed until the White House made public the results of his annual physical exam on Wednesday.

U.S. President George W. Bush was likely bitten by a tick that carried the Borrelia burgdorferi bacterium while mountain biking.
(CBC)

The White House said Bush was treated for "early, localized Lyme disease" last August after developing the characteristic bull's-eye rash and that it did not recur.

At Bush's most recent physical, done last month, doctors pronounced him healthy overall.

Lyme disease is an infection that requires prompt medical attention.

The culprits are blacklegged ticks that can carry a bacterium called Borrelia burgdorferi that causes Lyme disease.

If a tick bites a person after ingesting infected blood, it can pass on the infection. Health Canada estimates that about 10 per cent of blacklegged ticks in any infected area carry the bacterium that causes Lyme disease.

Symptoms, which can show up in three to 30 days, begin with a circular rash that surrounds the bite mark. The rash may be followed by symptoms like fatigue, chills, fever, headache, muscle and joint pain and swollen lymph nodes.

Lyme disease is generally easy to treat with antibiotics in its early stages. But if left too long, treatment may involve several rounds of antibiotics.

Left untreated, the disease can progress to a second phase, which can last several months. Symptoms in the second phase include migraines, weakness, multiple skin rashes, painful or stiff joints, abnormal heartbeat and extreme fatigue.

Long-term effects of failing to treat the illness include chronic arthritis and neurological symptoms, including headaches.

Lyme disease found across Canada

Health Canada offers several tips to protect yourself from tick bites.

• If infected ticks are in your area, wear long-sleeved shirts that fit tightly around the wrist and long-legged pants tucked into socks or boots.
• Light-coloured clothing makes it easier to see if there are ticks on your clothes.
• Wear shoes that cover your entire foot — avoid sandals in areas where ticks might be.
• Use insect repellents that contain DEET to repel ticks. Repellents can be applied to clothing as well as exposed skin.

The risk for exposure to the disease is highest in a small number of regions where the ticks that transmit Lyme disease are known to be established, including parts of southern and eastern Ontario, southeastern Manitoba and Nova Scotia as well as much of southern British Columbia, says the Public Health Agency of Canada. 

Most cases are reported in late spring and summer, when the young ticks are most active and people are outdoors more often.

It's suspected Bush suffered a tick bite while mountain biking, his main form of exercise and recreational activity.

With files from the Associated Press