High-Risk Areas for Lyme Disease

Lyme disease diagnoses are on the rise according to a new study published by the government this week. The geographic areas where Lyme disease appears to be the biggest danger has dramatically increased with U.S. cases remaining concentrated in the Northeast and upper Midwest. The study revealed that more areas in those regions are considered high-risk. With a total of 260 counties where the number of Lyme disease cases doubled is expected given the growing number of America's population. That increase is up from 130 just 10 years ago.




Lyme disease is the most commonly reported vector-borne illness in the United States, according to the Centers for Disease Control and Prevention (CDC).  

A vector-borne illness is one which is spread to humans through a vector, such as an insect or arachnid, carrying the disease.  In the case of Lyme disease, the vector is a tick.  More precisely, the illness is spread through the bite of a black-legged tick, or deer tick.  

Lyme disease is most common in wooded suburban and far suburban counties. Scientists aren’t sure why high-risk areas are expanding, but it likely has something to do with development and other changes that cause the deer and ticks that carry the bacteria to move. 

The illness was first identified in Connecticut in 1975 and 17 states now possess high-risk counties. These high-risk zones encompass nearly all of Massachusetts and New Hampshire and also half of Maine and Vermont.

Each year, approximately 30,000 cases of Lyme disease are reported, not to mention the countless cases which go unreported.   These cases are concentrated mostly in the Northeast and upper Midwest, where the bacteria is abundant.

Early prevention and treatment is important when dealing with Lyme disease, as the symptoms get progressively worse and more serious as time goes on.  Some common early symptoms include:

  • Small bump/redness at the site of the bite;
  • Red, expanding rash called erythema migrans (EM);
  • Fatigue, chills, fever, headache, muscle and joint aches, and swollen lymph nodes.

Although early treatment through antibiotics is available, Lyme disease can be difficult to diagnose – especially in the first few weeks after infection.  Blood tests for Lyme disease have better accuracy after the first few weeks because antibodies against the bacteria usually take a few weeks to develop.  Before this time, there is a higher possibility that tests can come out negative, even if Lyme disease is present because antibodies are not present or are too low to be detected.