Ticks in St. Lawrence County, New York are thriving and causing a significant increase in Lyme disease infections, with experts believing the rate is higher than reported. The county has a higher rate of Lyme disease than most of the US, with the increase potentially due to a rise in the mouse population last fall, caused by mild North Country winters. While the rate of Lyme has declined somewhat in the past three years, it increased from 0.9 cases per 100,000 population to 44.8 from 2002 to 2012. Lyme disease can cause long-term fever, chills, sweats, muscle aches, fatigue, nausea and joint pain.