This post originally ran on NACCHO’s Healthy People, Healthy Places blog. For more environmental health and infectious disease news and information, visit http://www.essentialelements.naccho.org.
By Prezley Duncan, Intern, Environmental Health, Pandemic Preparedness, and Catastrophic Response, NACCHO; and Lisa Brown, MPH, Senior Program Analyst, Environmental Health, Pandemic Preparedness, and Catastrophic Response, NACCHO
Anyone planning to spend quality time outdoors this summer likely knows that seasonal pests such as mosquitoes not only pose a nuisance, but also a public health concern. But mosquitoes, while perhaps the most well-known summer pests, are certainly not the only critters tempted by bare skin. Anyone planning to stray from city streets in the warm weather should be on the lookout for ticks, which can transmit a host of debilitating ailments, including Lyme disease.
The blacklegged tick, also known as the deer tick, is the carrier (vector) for Lyme disease. In recent years, reports of Lyme disease in the United States have significantly increased, and this year is no exception. The disease is the most commonly reported vector-borne illness in the United States. Driven by a multitude of factors, like climate and land use changes, the number and distribution of reported cases is has increased by as much as 200% in the last two decades. Incidence estimates of Lyme disease range from 240,000-440,000 new cases per year, but even that range may be low; it is difficult to pinpoint the exact impact of the disease due to reporting methods and recognition of symptoms. 
Blacklegged ticks survive best in moist wooded or forested areas which are very suitable because the trees provide shade and leaf litter. These habitats also support the deer populations on which the arachnids thrive. Blacklegged ticks seek hosts by climbing on grasses and shrubs and waiting for a host—such as a hiker—to rub against their hiding spot. When this occurs, the tick climbs onto the host’s body and attempts to attach and feed. Blacklegged ticks can attach to any part of the body but are usually be found in hard-to-see places, such as the groin, armpits, and scalp. Typically, it takes about one and a half to two days for the bacterium to be transmitted to the host, and an infected individual can expect symptoms to show anywhere between three and 30 days after the initial tick bite. Symptoms are similar to those of influenza, such as fatigue, fever, headache, muscle and joint pain, and swollen lymph nodes. The primary sign of Lyme disease, a rash that resembles a bull’s-eye, occurs in 70-80% of those infected.  And while individuals diagnosed early with Lyme disease can be successfully treated with a few weeks of antibiotics, others experience lifelong complications. Long-term neurological issues include numbness, pain, stiffness in the arms and legs, tremors, facial paralysis, and vision problems. And, while ticks are primarily an outdoor concern, they can be brought home on clothing or pets. However, most indoor environments are too dry for blacklegged ticks to survive for more than a few days. 
Overall, reducing exposure to ticks is the best defense against Lyme disease and other tick-borne infections. Preventative measures should be taken year-round, but special attention should be paid in the warmer months when ticks are most active. The Centers for Disease Control and Prevention (CDC) recommends avoiding woody and bushy areas, especially those with high grass. If unavoidable, it is best to walk in the center of trails and use repellents with DEET. When coming indoors, individuals should bathe as soon as possible and conduct a full body check, keeping in mind that ticks attach in hard-to-see areas. If a tick is found attached to skin, it can be safely and effectively removed with fine-tipped tweezers. It is important to use the fine-tipped tweezers to pull upward with a steady, even pressure. Twisting or jerking the tick could cause the mouth parts to break off and remain in the skin. 
The blacklegged tick is widely distributed in the northeastern and upper Midwestern United States, and in 2013, 95% of reported and confirmed Lyme disease cases were from 14 states alone.  However, recent studies show that changes are afoot, and blacklegged ticks are moving into new areas. As the climate continues to warm, ticks are expanding their geographic ranges, and moving to higher altitudes and latitudes where they previously couldn’t have survived. Studies show that climate change has contributed to the geographic expansion of ticks, increasing the potential public health risk of Lyme disease, which is already the most prevalent vector-borne disease in the United States.
Health departments in many of the states reporting Lyme disease cases have increased their efforts to educate residents on Lyme disease prevention and protection. Details of some of those efforts are discussed below.
Currently, Lyme disease is present in every Pennsylvania county. In the face of such a surge in the disease’s prevalence, the Allegheny County (PA) Health Department has partnered with Pennsylvania’s secretary of health to educate the public on preventative action that can be taken to avoid contraction of the disease. Additionally, the health department has used media outlets to raise awareness about the increased volume of ticks throughout the state, as well as the increased percentage of ticks that are infected with the Lyme disease-causing bacterium. Because of this surge, every county health department in the state has sent out warnings to residents. 
Vermont Department of Health is taking action against Lyme disease by working with counties to host educational programs. In Windham County, health officials hosted “Ticks and Lyme Disease: A Guide for Preventing Lyme Disease,” which teaches residents to recognize signs and symptoms and emphasizes the widespread need for prevention and protection throughout communities. The Vermont Department of Health also hosts a “Be Tick Smart” annual video contest encouraging high school students to create a sixty second video about Lyme disease prevention. 
The Loudon County Health Department of Virginia, partnering with the Loudon Lyme Disease Commission, Medical Reserve Corps, and other community partners, works to mitigate the tick-borne disease through the “Loudoun Targets Lyme” program. The program, which is recognized by the Virginia Association of Counties as a model program, focuses on community outreach and events, such as an annual ”Fun Run.” Program coordinators are also working towards having Lyme disease Public Service Announcements presented at local movie theaters. 
Local and state health departments such as those mentioned above are working on the front lines to prevent and control the possible spread of tick-borne diseases, such as Lyme disease. However, tick-borne diseases are among the most difficult infectious diseases for local health departments to predict, prevent, and control. Local health departments should work with their state health department and other local agencies to assure they are able to monitor tick populations, measure of the presence of the virus, and identify human cases. Local health departments should review education plans for the public, medical providers, and laboratories serving their community. Awareness of the virus and disease, recognition of symptoms, personal measures for preventing tick bites, and community measures for eliminating ticks and their breeding sites are all parts of a comprehensive disease prevention and control educational campaign. Local health departments should rely on public health measures like surveillance, prevention, response, and education. Summer is the perfect time to go and enjoy the great outdoors, but protective and preventative practices are essential in evading tick bites.
For more information on Lyme disease and other vector-borne diseases, visit:
- Vector-Borne Disease Control (NACCHO)
- Division of Vector-Borne Diseases (CDC)
- Lyme Disease (CDC)
- Reported Cases of Lyme Disease (CDC)
- Approximate Distribution of the Blacklegged Tick (CDC)
- Lyme Borreliosis (WHO)
- Adrion, E. R., Aucott, J., Lemke, K. W., & Weiner, J.P. (2015). Health Care Costs, Utilization and Patterns of Care following Lyme Disease. Plos ONE, 10(2). Doi: 10.1371/journal.pone.0116767
- Entomological Society of America. (2014, July). Fewer deer may mean less lyme disease. Retrieved June 30, 1015 from http://www.entsoc.org/press-releases/fewer-deer-may-mean-less-lyme-disease.
- Centers for Disease Control. (2015 June). Lyme disease. Retrieved June 15, 2015 from http://www.cdc.gov/lyme/index.html.
- Centers for Disease Control. (2015 March). Tick removal. Retrieved June 15, 2015 from http://www.cdc.gov/lyme/removal/index.html.
- Centers for Disease Control. (2015 March). Lyme disease data and statistics. Retrieved June 15, 2015 from http://www.cdc.gov/lyme/stats/index.html.
- Wade, M. (2015 June). Health department reminds public to protect from ticks, avoid Lyme disease. Retrieved June 16, 2015 from http://www.achd.net/pr/pubs/2015release/061015_lyme.html.
- Vermont of Health. (2015). Lyme disease in Vermont. Retrieved June 11, 2015 from http://healthvermont.gov/prevent/lyme/lyme_disease.aspx.
- Loudoun County. (2015). Loudoun Targets Lyme. Retrieved June 30, 2015 from http://www.loudoun.gov/index.aspx?NID=2899.
- Centers for Disease Control. (April 2014). Preventing Tick Bites. Retrieved June 30, 2015 from http://www.cdc.gov/ticks/avoid/on_people.html.