Prior to the late 1970’s, tick-borne diseases in New Jersey were relatively rare and not considered a major public health threat. Rocky Mountain spotted fever (RMSF) was the only tick-borne disease recognized in New Jersey at that time. The first cases of Lyme disease were reported in New Jersey in 1978 and since then, it has been the most commonly reported tick-borne disease in the United States. The majority of Lyme disease cases occur in the Northeast. New Jersey consistently ranks among the states reporting the most cases. Recently, several other tick-borne diseases have become a concern, including human granulocytic ehrlichiosis (HGE), human monocytic ehrlichiosis (HME), and babesiosis. The geographical distribution and public health importance of these emerging tick-borne diseases in New Jersey is not well understood at this point. Three ticks, called vectors, are responsible for all tick-borne disease transmission in New Jersey:
1. black-legged tick or more commonly known as the deer tick
2. lone star tick
3. American dog tick
Each of these species is a 3-host tick, meaning it must locate and obtain a bloodmeal from a host animal in each of its active developmental stages (larva, nymph, adult) to complete its life cycle. The role that various hosts play in the transmission cycles is critical to understanding tick-borne diseases. Certain animals provide a source of blood only and are termed maintenance hosts. Those that provide a bloodmeal and a source of disease organisms are called reservoir hosts. Certain hosts, such as birds, are also responsible for dispersal of ticks over long distances. The
ticks involved in disease transmission in New Jersey are not host-specific, that is, they will feed on a variety of animals. The type of host generally is determined by the behavior of the tick species and life stage. Humans are considered incidental hosts. The transmission cycles of the various tick-borne diseases have both similarities and differences. Lyme disease, human granulocytic ehrlichiosis, and babesiosis share a common reservoir host (white-footed mouse) and tick vector (black-legged tick), both of which are most frequently encountered in forested habitats. Rocky Mountain spotted fever has a different reservoir host and tick vector (American dog tick), which exploits habitats quite different from the other tick species. Therefore, an understanding of these differences is important in reducing exposure to infected ticks and minimizing transmission risk.
PREVENTION
The best way to prevent tick-borne diseases is to avoid tick-infested areas, including woodland, wooded edges, and landscaped areas with dense ground cover, leaf litter, or shrubs. If this is not possible, take the following precautions when entering likely tick habitats.
- Wear light-colored clothing, making it easier to see ticks.
- Tuck pants legs into socks and shirts into pants. Ticks will be forced to crawl on the outside of clothing, where they can be more easily seen and removed.
- Use repellents. Personal repellents which contain DEET can be used on skin or clothing, while repellents containing permethrin should only be used on clothing. Be certain to read label directions carefully.
The risk of transmission can be reduced further by examining yourself and family members when returning from tick-infested areas and removing ticks before they have a chance to feed. Ticks require a relatively long time to insert their mouthparts and begin feeding. Ticks that are removed promptly are unlikely to transmit disease organisms. Ticks embedded in the skin should only be removed by grasping the tick with pointed tweezers as close to the skin as possible and applying firm, steady backward force until the tick becomes dislodged. Attempts to remove attached ticks with noxious chemicals or by burning will not work, may cause injury to the skin, and can increase the risk of transmission by causing the tick to regurgitate disease organisms into thebody. After the tick has been removed, wash the skin area thoroughly to avoid infection.
1. black-legged tick or more commonly known as the deer tick
2. lone star tick
3. American dog tick
Each of these species is a 3-host tick, meaning it must locate and obtain a bloodmeal from a host animal in each of its active developmental stages (larva, nymph, adult) to complete its life cycle. The role that various hosts play in the transmission cycles is critical to understanding tick-borne diseases. Certain animals provide a source of blood only and are termed maintenance hosts. Those that provide a bloodmeal and a source of disease organisms are called reservoir hosts. Certain hosts, such as birds, are also responsible for dispersal of ticks over long distances. The
ticks involved in disease transmission in New Jersey are not host-specific, that is, they will feed on a variety of animals. The type of host generally is determined by the behavior of the tick species and life stage. Humans are considered incidental hosts. The transmission cycles of the various tick-borne diseases have both similarities and differences. Lyme disease, human granulocytic ehrlichiosis, and babesiosis share a common reservoir host (white-footed mouse) and tick vector (black-legged tick), both of which are most frequently encountered in forested habitats. Rocky Mountain spotted fever has a different reservoir host and tick vector (American dog tick), which exploits habitats quite different from the other tick species. Therefore, an understanding of these differences is important in reducing exposure to infected ticks and minimizing transmission risk.
PREVENTION
The best way to prevent tick-borne diseases is to avoid tick-infested areas, including woodland, wooded edges, and landscaped areas with dense ground cover, leaf litter, or shrubs. If this is not possible, take the following precautions when entering likely tick habitats.
- Wear light-colored clothing, making it easier to see ticks.
- Tuck pants legs into socks and shirts into pants. Ticks will be forced to crawl on the outside of clothing, where they can be more easily seen and removed.
- Use repellents. Personal repellents which contain DEET can be used on skin or clothing, while repellents containing permethrin should only be used on clothing. Be certain to read label directions carefully.
The risk of transmission can be reduced further by examining yourself and family members when returning from tick-infested areas and removing ticks before they have a chance to feed. Ticks require a relatively long time to insert their mouthparts and begin feeding. Ticks that are removed promptly are unlikely to transmit disease organisms. Ticks embedded in the skin should only be removed by grasping the tick with pointed tweezers as close to the skin as possible and applying firm, steady backward force until the tick becomes dislodged. Attempts to remove attached ticks with noxious chemicals or by burning will not work, may cause injury to the skin, and can increase the risk of transmission by causing the tick to regurgitate disease organisms into thebody. After the tick has been removed, wash the skin area thoroughly to avoid infection.
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