10 States Where Tick-Borne Lyme Disease Is a Big Issue

As the most common vector-borne disease in the United States, about 476,000 people are infected by Lyme disease annually. Typically caused by the bacterium Borrelia burgdorferi and, on occasion, Borrelia mayonii, it is transmitted to humans through infected blacklegged ticks. If detected early, Lyme disease is easily treated by antibiotics. However, if not treated, the infection may spread to joints, the heart, and the nervous system. Let’s examine the ten states where tick-borne Lyme disease is a big issue.

10. Wisconsin

The number of reported cases of Lyme disease in Wisconsin has more than doubled in the last 15 years. Lyme disease and the tick species that carry it are native to Wisconsin, and the wooded and grassy terrain of the state is ideal for these ticks. Plus, over the last few years, Wisconsin experienced warmer winters than average, which means a better survival rate for ticks.

Lyme disease-carrying ticks are present in all 72 counties in Wisconsin, so you must do thorough checks after being in forested or tall grass areas. Removing a tick in the first 24 hours reduces your chance of getting Lyme disease.

According to CDC 2019 data, Wisconsin had:

• Incidence rate: 20.9
• Confirmed cases: 1,219
• Probable cases: 959

So, when evaluating Lyme disease cases, Wisconsin ranks tenth on the list of states where tick-borne Lyme disease is a big issue.

9. Connecticut

Interestingly, Lyme disease gets its name from a small coastal town in Connecticut called Lyme. In 1975, Yale researchers examined an unusual amount of pediatric arthritis cases in the area, eventually named “Lyme disease” in 1979.

With the warmer and shorter winters the state is experiencing, ticks are now active all year. In the past, Connecticut would typically see 50 ticks at the Connecticut Agricultural Experiment Station between December 1^st and March 31^st. Now, the station is seeing up to 800 ticks. Also, as more of the Connecticut landscape is converted to suburban neighborhoods, there are fewer predators and hunting of the white-tailed deer. Unusually high numbers of white-tailed deer, the main host of blacklegged ticks, means an abundant food supply for the ticks.

According to CDC 2019 data, Connecticut had:

• Incidence rate: 22.3
• Confirmed cases: 795
• Probable cases: 438

This makes Connecticut one of the ten states most affected by Lyme disease.

8. New Jersey

The tick species that carry Lyme disease are expanding their territory into New Jersey. Unfortunately, the milder winters in New Jersey mean good conditions for a tick’s survival. They can withstand temperatures of 20°F and above. To truly cut down on the tick population, you need temperatures between -2°F to 14°F for a week or longer. New Jersey is seeing fewer of those extended temperatures during the winter.

According to CDC 2019 data, New Jersey had:

• Incidence rate: 27
• Confirmed cases: 2,400
• Probable cases: 1,219

Unfortunately, those milder winters put New Jersey in the top ten states where Lyme disease is a big issue.

7. West Virginia

Unfortunately, over 20 percent of blacklegged ticks in West Virginia are infected with the bacteria that causes Lyme disease. Plus, the wooded landscape and outdoor culture of West Virginia make tick exposure more likely.

According to CDC 2019 data, West Virginia had:

• Incidence rate: 39.2
• Confirmed cases: 703
• Probable cases: 182

While West Virginia is another location where Lyme disease is a big issue, healthcare professionals advise residents to wear long pants and shirts when going through wooded areas and apply repellent containing Deet.

6. Rhode Island

Blacklegged ticks are also expanding into Rhode Island with the warmer temperatures. Not only are the milder winters making northern states like Rhode Island more tolerable, but hotter temperatures in the South are becoming intolerable for ticks. According to research by the United States Geological Survey and affiliates, ticks attach to hosts at the top of leaf litter or twigs. But, because of the hotter temperatures in southern states, ticks hide underneath leaf litter to survive. This means fewer ticks are attaching to humans, thus transmitting Lyme disease.

According to CDC 2019 data, Rhode Island had:

• Incidence rate: 49.7
• Confirmed cases: 527
• Probable cases: 444

While Lyme disease is a problem in Rhode Island, it most adversely affects children between the ages of five and nine. Tick checks, protective clothing, and repellent are important for your children.

5. Pennsylvania

Because of climate change and the rise in available hosts, blacklegged ticks are expanding their range across Pennsylvania. White-tailed deer and white-footed mice, easy hosts for the blacklegged tick, are plentiful, and their populations are expanding. These factors support the increasing tick numbers.

According to CDC 2019 data, Pennsylvania had:

• Incidence rate: 52.8
• Confirmed cases: 6,763
• Probable cases: 2,235

This is why Pennsylvania is ranked fifth for Lyme disease incidences per 100,000 people.

4. Delaware

Lyme disease is reported in all three counties in Delaware all year round. However, Delaware’s high rate of Lyme disease may be due to the lack of state awareness about the disease. A study led by Dr. Sangeeta Gupta shows that only 38.4 percent of residents think ticks are a problem in Delaware. And only 13 percent agreed that Lyme disease was a problem in their state.

Insufficient awareness campaigns and educational programs contribute to the limited understanding and prevention of tick-transmitted Lyme disease in Delaware.

According to CDC 2019 data, Delaware had:

• Incidence rate: 63.6
• Confirmed cases: 619
• Probable cases: 22

While Delaware’s landscape and animal population makes it an ideal habitat for blacklegged ticks, perhaps it would not be in the top five states for Lyme disease if awareness was more prevalent.

3. New Hampshire

Blacklegged ticks are in all ten counties of New Hampshire, but the population density is highest in the southeast. These ticks are especially troublesome for residents because they carry more than Lyme disease. A 2007 study found the blacklegged ticks in New Hampshire carried pathogens that cause babesiosis and anaplasmosis. The ticks even have the potential to carry the Powassan virus.

According to CDC 2019 data, New Hampshire had:

• Incidence rate: 81.3
• Confirmed cases: 1,106
• Probable cases: 604

These rates make New Hampshire one of the top three states where Lyme disease is a big issue.

2. Vermont

Lyme disease cases used to be rare in Vermont. In the 1990s, the Vermont Health Department received perhaps a dozen reported cases yearly. Now, there are 500 cases or more reported per year since 2011. Residents are most at risk of an infected tick bite between April and July in Vermont. While residents of every county have the chance of being infected, Lyme disease rates are far higher in Windham, Bennington, and Rutland counties.

According to CDC 2019 data, Vermont had:

• Incidence rate: 113.1
• Confirmed cases: 706
• Probable cases: 358

Vermont ranks second in the United States where Lyme disease is a big issue.

1. Maine

The number of Lyme disease cases in Maine keeps growing each year. Part of this is because of the longer tick season due to warmer than usual temperatures. Also, areas traditionally too far north for ticks, such as Fort Kent, Houlton, and Presque Isle, are seeing increasing tick numbers.

The good news is that the University of Maine received $6.2 million in federal funding this year for tick research. The University of Maine will use the money to research ways to control tick populations, identify emerging tick species, and, overall, expand public health efforts to educate and create awareness in Maine.

According to CDC 2019 data, Maine had:

• Incidence rate: 121.2
• Confirmed cases: 1,629
• Probable cases: 538

Currently, Maine is the state where Lyme disease is the biggest problem.

Summary of 10 States Where Tick-Borne Lyme Disease is a Big Issue

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