The purpose of this article is to provide some basic information about ticks, as well as key details about the various species that you are most likely to encounter in different regions of the United States. If you suspect that you or a loved one has been bitten by a tick of any kind, try to keep it as in-tact as possible and take it in a secure container to your healthcare provider, veterinarian, or local vector control for identification.
What Are Ticks?
Ticks are a type of insects called arthropods. Like spiders, they fall under the classification of arachnids—a specific type of arthropod with eight legs. Unlike spiders, however, ticks feed on blood from mammals—including people, pets and livestock—as well as birds, reptiles, and amphibians. They have been reported in rural and urban environments around the world, but are most often found in grassy or wooded areas and are typically most active from spring through fall.
In general, ticks can be divided into two main families: hard ticks (Ixodidae) and soft ticks (Argasidae).
HARD TICKS (IXODIDAE) Hard ticks all share the distinguishing trait of a hard outer shield or black plate, known as a scutum.
SOFT TICKS (ARGASIDAE) Soft ticks do not have a scutum but instead have more rounded bodies.
Both of these families of ticks have species that can transmit diseases to humans; however, the typical length of time required to do so differs just like their feeding habits. Certain hard ticks that carry Lyme disease, for example, typically must be attached for 36 to 48 hours to infect a host, according to the Centers for Disease Control (CDC). Certain soft ticks that transmit Tick-Borne Relapsing Fever (TBRF), however, feed very quickly and can cause disease in humans.
What is the Typical Lifecycle of a Tick?
Ticks generally have four stages of life: egg, larvae, nymph and adult. Eggs, which can number into the thousands are laid by the female tick. These eggs hatch into larvae, which are also known as “seed ticks.” The larvae typically attach to smaller animals, such as mice and birds. After several days of feeding, the larvae develop into nymphs, which can then attach to larger hosts and then ultimately turn into adult ticks. Ticks advance through each of these stages by molting, a process during which they shed their outer skin.
What Types of Ticks Transmit Diseases to Humans?
Of the nearly 900 species of ticks that exist in the world, only a select number bite and transmit disease to humans within the United States. The following descriptions provide key facts about each of these different types of ticks, including what each tick looks like at various stages of the lifecycle, some distinguishing characteristics, regions where they’re typically found, and the potential diseases they can transmit to both people and pets.
- AMERICAN DOG TICK
- EASTERN BLACKLEGGED TICK/DEER TICK
- BROWN DOG TICK
- GULF COAST TICK
- LONE STAR TICK
- ROCKY MOUNTAIN WOOD TICK
- WESTERN BLACKLEGGED TICK
- SOFT TICKS
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