Tick-Borne Infections—A Growing Public Health Threat to School-Age Children

Abstract

School nurses are experts in school health services and frequently front-line providers of care for school-age children presenting with symptoms of physical illness or behavioral, cognitive, learning, and/or psychological problems possibly due to tick-borne infections. School nurses need to know how to protect children on school property and during school sponsored outdoor activities from being bitten by ticks that can transmit diseases. Since infection prevention is a primary objective in health care, this article will empower school nurses with key information about how to accomplish this goal.

Keywords

risk behavior behavioral problems infection prevention immunizations/infectious diseases role of the school nurse National Association of School Nurses

The U.S. Centers for Disease Control (CDC) reported that tick-borne infections are an increasing public health concern and occur in every state (CDC, 2011a, 2011c). School-age children are particularly at risk from tick-borne diseases (Rand et al., 2007), and NASN at the U.S. Environmental Protection Agency conference, “Promoting Community IPM for Preventing Tick-Borne Diseases,” expressed the importance of preventing tick bites to children (Schoessler & Schantz, 2011). Many of the tick control and bite prevention practices discussed in this article are addressed in the document, A Strategic Plan for Integrated Pest Management in Schools in the United States, a state and governmental program focused on reducing pesticide exposures to school children while providing protection from unmanaged pest infestations (Green & Gouge, 2008).

While there are several tick-borne infections, the most well known is Lyme disease (spirochetal bacterium, Borrelia burgdorferi), with nearly 30,000 cases reported each year (CDC, 2011c). Underreporting of tick-borne infections is common and concerning because of the high incidence of infection in school-age children (CDC, 2010; Young, 1998) and the frequent outcome of undiagnosed infection resulting in academic performance deficits (Hamlen & Kliman, 2010; Lyme Disease Association, 2010). Less well-known tick-borne infections are Ehrlichia and Anaplasma species (rickettsial bacteria), Bartonella species (bacteria), Mycoplasma species (bacteria), Babesia species (protozoan parasites), and Southern tick-associated rash illness (STARI) (spirochetal bacterium) (CDC, 2011c; Owen, 2006; Sykes, Lindsay, Maggi, & Breitschwerdt, 2010). While the reported cases for these tick-borne infections are not as high as for Lyme disease, these infections occur in children and cause serious illnesses (Hamlen & Kliman, 2010; Marshall et al., 2002; Nicolson, 2007; Schutze et al., 2007). These disease-causing microorganisms are primarily transmitted by the attachment and feeding (bite) of an infected deer or a lone star tick that is the size of a poppy seed and often goes unnoticed (CDC, 2011b; Hamlen, 2011). The risk of infection with one or more of these microorganisms differs by geographic location; however, every tick attachment has the potential of transmitting multiple infections (Owen, 2006; Swanson, Neitzel, Reed, & Belongia, 2006; Sykes et al., 2010). Children with multiple infections are more ill than if singly infected (Krause et al., 1996; Owen, 2006).

The initial indications of tick-borne infections in children can include but are not limited to a reddish rash, flulike illness (fever and chills), fatigue, joint and muscle pain, headache, and stiff neck. Later symptoms can include cognitive and memory deficits, decreased school performance, poor frustration management, sleep disturbance, and neuropsychiatric impairments (Fallon, Kochevar, Gaito, & Nields, 1998; Hamlen & Kliman, 2010; Lyme Disease Association, 2010; McAuliffe & Brassard, 2008; Tager et al., 2001).

Although many school nurses are alert to the impact of tick-borne infections on behavior and academic performance (Hamlen & Kliman, 2009; Healy, 2000), there is little published information in the school nursing literature on how to prevent school-age children from being bitten by ticks. This article will provide school nurses with information and recommendations for administrators that can decrease the risk of tick bites on school property and also inform teachers and parents of steps they can take to reduce the risk of tick bites on school sponsored outdoor activities.

School and Residential Exposure to Ticks

In suburban and semi-rural areas, a significant number of pediatric infections originate in the outdoor home environment (Connally et al., 2009). Children who participate in school sponsored outdoor recreational activities in tick-infested areas are at greatest risk of getting tick-borne infections. Activities in shady environments that include ground cover, moist humus, leaf litter, and poorly maintained trails are ideal habitats for ticks and increase the risk of tick bites (Klein, Eppes, & Hunt, 1996). As outdoor activities increase each spring, so does the risk of tick bites, for ticks become active at 40°F (Lane, Steinlein, & Mun, 2004).

Areas suspected of harboring ticks can be assessed for the presence of ticks by a tick drag. A white corduroy or cotton cloth (3 feet by 4 feet) stapled to a dowel is dragged across the area, including low brush, and then the cloth inspected for ticks. One area of elevated risk for encountering ticks is the shady border where the school playground, park, field, lawn, or trail meets wooded areas with deer populations (Jackson, 2003; Jackson, Hilborn, & Thomas, 2006). Children should not enter this dangerous border area, for example, while retrieving a ball or engaging in other activities. School play equipment should not be placed in this border area but in sunny areas where ticks cannot survive. Leaf litter should be raked, tall grasses and brush around school play areas cleared, and trees trimmed to open up wooded play areas to allow sunlight to penetrate and reduce the ground level moisture that ticks need to survive. Placing a fence and/or several feet of wood chips or gravel along the border would help keep ticks away from child inhabited areas (CDC, 2011b; Hamlen, 2011).

The playground–woods border and adjacent woods should be sprayed (avoiding play equipment) with a targeted barrier acaricide (product to kill ticks) such as permethrin, bifenthrin, deltamethrin, cyfluthrin, cypermethrin, cyhalothrin, or carbaryl (Sevin^®) in the spring and fall. It is advisable to flag treated areas until safe to enter. Border/targeted barrier applications can be made on non-school days and provide insignificant exposure to children who will use the school playground post-spraying. Acaricide applications can be made by professional pest control experts or school maintenance personnel. Ready-to-spray products that attach to a hose for application can be purchased at home and garden centers. No license is required for these products. Local school pesticide polices and/or state green laws should be consulted prior to application of acaricides (IPM Institute, 2011).

The animals (hosts) that ticks live on can also be treated. Two effective host-targeted approaches to tick control are the four-poster deer treatment station¹ and Damminix^® tick tubes² (Pound et al., 2009). These products are an additive approach to targeted barrier sprays, can be used around school property, and are available from www.crdaniels.com and www.damminix.com/default.asp.

Non-pesticide tick control products include garlic sprays (Mosquito Barrier^®) and the fungal tick pathogen, Metarhyzium anisopliae (Tick-Ex^® and Taenure^®) (Bharadwaj & Stafford, 2010). In field studies, Mosquito Barrier has produced only short-term tick suppression compared to acaricides, and M. anisopliae products currently are not commercialized. Additional non-pesticide products are in early field evaluations (Dolan et al., 2009).

Outdoor Activities

School sponsored outdoor activities, including hiking or camping, are an important aspect of the school curriculum and provide significant teaching opportunities in natural settings (Louv, 2008).

Those same natural settings are also tick habitats, and there are a number of precautions that children should take to avoid tick bites. (1) Avoid sitting directly on the ground, stonewalls, woodpiles, or fallen logs, as these are likely to be tick infested, and instead use a piece of impervious ground cover, for example, Gore-Tex^®, as a barrier. (2) Walk in the center of well-maintained trails and avoid brushing against vegetation along the trail. (3) Avoid hiking on deer trails and walking in leaf litter and tall grass, the habitat of ticks in the spring and fall. (4) Check for ticks periodically while in tick-infested areas.

The California Lyme Disease Association (2001) has created a field trip tick alert form that includes information about appropriate protective clothing and important points to consider before engaging in an outdoor activity. This form³ is an excellent vehicle to educate parents on the risks that their children can encounter on a school outing and precautionary steps to take to reduce the risk of a tick bite.

Outdoor Clothing

To increase the chance of seeing ticks on children, their clothing should include light-colored long pants, long-sleeved shirt, and closely knitted socks. Shirts should be tucked into pants and pants into socks. These steps will help prevent a tick from crawling under the clothing and getting to a child’s skin. Children should wear a hat and neck bandana to decrease the chance of picking up ticks. After a school outdoor activity in tick habitations, it is advisable to keep outdoor clothing out of the school or home or in a sealed plastic bag to be sure that ticks cannot migrate from clothing into the school or home. During hot weather, it is inevitable, but not recommended, that shorts and short-sleeved shirts will be worn on outdoor activities. It is essential that all exposed skin be treated with an effective tick repellent.

Permethrin Treatment for Outdoor Clothing

Many parents are concerned about adding more chemicals to their children’s lives. While this is understandable, it is important for them to make a risk/benefit balance analysis: What are the risks of being bitten by an infected tick balanced by the benefits of tick-control chemicals? The absence of preventive chemicals can necessitate a later use of treatment chemicals such as antibiotics and antimicrobials.

For treating outdoor clothing, the most effective chemical to kill ticks is permethrin (Mencke, 2006). Permethrin is available as both an aerosol and a spray product under several brand names including Sawyer^®, Duranon^®, Permanone^®, and Ultrathon^® Clothing and Gear Spray. These products can be found in outdoor retail stores in the camping section or online but generally are not available at drug stores.

It is essential to spray shoes, boots, socks, pants, shorts, shirts, and bandanas with permethrin. Before a school hiking or camping activity, parents should hang clothing on an outdoor clothesline, spray them until damp with permethrin, and let dry before use. A soak-treatment product is available that entails placing outdoor clothing in a plastic bag that contains the permethrin solution and then allowing it to dry before use. Permethrin treatments last 2 to 6 weeks depending on the permethrin brand used, and effectiveness remains through several washings. Label directions should be followed carefully. Permethrin should not be applied to the skin and not sprayed indoors or in enclosed areas. It is also advisable to keep treated clothes out of the school or home or in a sealed plastic bag to ensure that the rare tick that might have survived exposure to permethrin cannot enter the school or home.

Insect Shield^® outdoor clothing, developed by the U.S. Department of Defense (DoD) and the standard military field clothing, is permethrin-pretreated, is effective through 70 washings, and has proven successful in preventing tick bites (Miller, Rainone, Dyer, Gonzalez, & Mather, 2011; Vaughn & Meshnick, 2011). Insect Shield^® clothing is available for children from ExOfficio, L.L. Bean, Orvis, REI, or online. While expensive, Insect Shield^® is an alternative for parents who do not wish to treat their children’s clothing. Although highly toxic to ticks, permethrin is one of the least toxic insecticides and safe for children once sprays have dried on clothing (Health Protection and Readiness, 2010).

Skin Protection (Repellents)

Parents of small children may have a chemical safety concern when using tick repellents such as DEET, and the same risk/benefit balance analysis should be applied: What are the risks of being bitten by an infected tick balanced with the benefits of tick-repellent chemicals? Chemical exposure to tick repellents is generally brief and long-term exposure not presumed to be an issue (U.S. Environmental Protection Agency, 2007).

Tick repellents containing DEET are widely available under many brands including OFF^®, Deep Woods OFF^®, Cutter^© Backwoods, etc. and can be used on skin or clothing (Carroll, Benante, Kramer, Lohmeyer, & Lawrence, 2010). Higher concentrations provide longer protection, but directions should be read carefully before applications on children (U.S. Army Public Health Command [USAPHC], 2010).

Ultrathon™, a DEET repellent developed by the DoD, is a sustained-release DEET-polymer formulation available as a lotion, aerosol, and pump and can provide up to 12 hours of protection, longer than other DEET repellents (Schofield, Tepper, & Gadawski, 2007). Ultrathon™ is labeled for children and is the standard military repellent worldwide (U.S. Army Center for Health Promotion and Preventive Medicine, 2007).

Effective non-DEET repellents labeled for children include BioUD™ and picaridin, for example, Natrapel^® (Bissinger et al., 2009; Carroll et al., 2010). Plant oils, such as lemon eucalyptus extract, are reported to be tick repellents, although their effectiveness is less than for DEET, BioUD, or picaridin (Jaenson, Garboui, & Pålsson, 2006; USAPHC, 2010).

Repellents should be applied carefully with none getting into the eyes or mouth. Small children should not have repellent applied to their hands and risk ingesting. Parents should be advised that their children should shower as soon as possible after exposure to tick habitats and use a washcloth to remove unattached ticks that may have escaped the permethrin-treated clothing or repellent barrier. Washing also removes any residual repellent and lessens exposure. With overnight school activities, showers after the exposure should be included in the schedule.

Pets

Dogs and cats are not generally part of the school environment, but they are important members in many homes with school-age children. The incidence of tick-carrying dogs and/or dogs infected with tick-borne diseases is exploding in tick-intense geographies, posing a significant risk to families with small children and dogs (Chomel, 2011; Dryden & Hodgkins, 2010). This risk is also true for cats. Unfortunately, many parents are unaware of the risk that tick-infested pets can present to their children. Outdoor pets, even if treated with effective protective products, can still transport unfed ticks into the home where they can crawl onto and bite children during normal pet–child play. It is advisable (but difficult to convince pet owners) that pets should be either indoors or outdoors and that free-range pets should not enter the home.

Pet tick-control products generally are effective in protecting the pet but do not keep ticks off the pet’s fur, allowing an unfed tick to fall off and survive in the home (Dryden & Hodgkins, 2010; Mencke, 2006; Sabnis, Zupan, & Gliddon, 2007). There is a high geographic correlation of canine and human tick-borne diseases, and a canine case of a tick-borne disease is a warning of infection in family members, especially children because of their playful activities with pets (Little, Heise, Blagburn, Callister, & Mead, 2010).

Conclusion

The most effective preventive approach for school-age children is to avoid tick habitat. However, if considering an outdoor trek or school outing into tick-infested areas, it is advisable to wear permethrin-treated clothing and protect exposed skin with an effective repellent. The DoD regulation Insect Repellent System for military personnel requires permethrin-treated clothing and an effective repellent, for example, Ultrathon™ (U.S. Army Center for Health Promotion and Preventive Medicine, 2007). The public is the benefactor of the U.S. military’s vital role in the development and testing of many of the most effective tick repellents and protection products commercially available today (USAPHC, 2010).

By learning and following the information in this article, school nurses can play a significant role in assisting school personnel to create tick-safe school environments and inform parents and teachers of effective methods to avoid tick bites while on school sponsored outdoor activities. Remember that all chemicals work because they have some form of toxicity to either repel or kill ticks. Use care with all chemicals and keep the risk-benefit assessment in mind. ■

Footnotes

Notes

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