What You Need to Know About Getting a Tick Bite

Although tick bites can be harmless—if no symptoms occur—ticks can expose humans to serious diseases caused by viruses, bacteria, or parasites, which are commonly carried by many tick species. The most common disease transmitted to humans via tick bites is Lyme disease, according to Centers for Disease Control and Prevention (CDC).

Tickborne Illnesses

Other than Lyme disease, there are several other serious conditions that are commonly spread to humans and other mammals by tick bites.

• Lyme disease: Transmitted by the western black-legged tick along the Pacific coast and the black-legged tick (commonly referred to as the deer tick) in the northeastern region of the United States
• Babesiosis: Caused by a parasite that lives on the black-legged tick
• Ehrlichiosis: Transmitted by the Lone Star tick, which is primarily in the south central and eastern regions of the United States
• Rocky Mountain Spotted Fever: Transmitted by several species of ticks including the American dog tick, Rocky Mountain wood tick, and the brown dog tick
• Anaplasmosis: Transmitted primarily by the black-legged tick
• Southern Tick-Associated Rash Illness (STARI): Transmitted from tick bites from the Lone Star tick found in the southeastern and eastern regions of the United States 
• Tick-Borne Relapsing Fever (TBRF): Transmitted from infected soft ticks (associated with ticks in rustic cabins or vacation homes) in 15 states across the United States
• Tularemia: Transmitted by the dog tick, the wood tick, and the Lone Star tick; prevalent throughout the United States

Other less common tickborne illnesses in the United States include:

• Colorado Tick Fever: Caused by a virus transmitted by the Rocky Mountain wood tick, which is found in the Rocky Mountain states
• Powassan Encephalitis: Transmitted by the black-legged tick (deer tick) and the groundhog tick; found in the Great Lakes region of the northeastern states.

Incidence of Tick Bites

Overall, disease-spreading species of ticks can be found in every state in the United States (excluding Hawaii). Tick bites are said to be on the rise today. In fact, according to the CDC, over 30,000 people in the United States are diagnosed with Lyme disease (from tick bites) each year. 

This number has tripled compared to the incidence of Lyme disease in the 1990s. 

Despite the growing number of reported tick bites (resulting in diseases such as Lyme) each year, many people are unaware of the prevalence of tickborne illnesses. Many others are unaware of the signs and symptoms of tick bites. In fact, according to a report by the CDC, nearly 20% of people surveyed across the nation were unaware of the risks posed by tick bites. 

Statistics show that between 20 and 40% of black-legged ticks (deer ticks) carry Lyme disease, according to scientist Richard Ostfeld Ph.D. of the Cary Institute of Ecosystem Studies in New York.

Findings of the increasing exposure to tick bites in the United States from the Cary Institute include:

• The greatest threat of disease in humans is caused by the black-legged tick (which are as small as a poppy seed and abundantly found from May through July).
• Climate change is causing the black-legged tick to expand its range north. 
• Warmer temperatures from climate change result in an earlier emerging of ticks in the spring, which in turn, increases the number of tick bites and tick-borne illnesses.
• A tick that feeds on a person for 36 hours can result in exposure to several disease-causing pathogens and could potentially cause Lyme disease, babesiosis or anaplasmosis.

Characteristics of Ticks

There are many varieties of ticks, but all are relatively small parasites that live off the blood of humans or other animals. Ticks are not insects, but they are in the arachnid category (like spiders and mites). Ticks vary in size, ranging from as small as the head of a pin to as big as a marble.

Various types of ticks range in color from black to shades of brown or reddish-brown. The color may change to a reddish brown or a greenish-blue shade after a tick has fed on its host (a human, a mouse, a bird, or other animals) for a few days and they become engorged with blood.

Identifying Deer Ticks

Because black-legged ticks (deer ticks) transmit the highest number of tickborne illnesses (compared to other types of ticks) it’s important to be able to identify them.

Further characteristics of black-legged ticks include:

• Brownish in color (but may change to brownish-red after feeding)
• Eight legs (as adults)
• Nymphs or young ticks are approximately 1 to 2 millimeters in length (the size of a pinhead) and are the most likely to spread Lyme disease and other tickborne illnesses
• Larvae, known as seed ticks, are less than 1 mm in length (the size of a poppy seed) and have only six legs—they can live up to six months in the environment before the need to find a host
• Adults are typically 3 to 5 mm in length
• Females are typically larger than the males and are red and brown in color

How Humans Get Tick Bites

Ticks do not jump or fly, they simply crawl onto humans or dogs (or other animals) from plants, foliage, or objects near the ground. Dogs and cats commonly carry ticks into the house, and ticks can subsequently crawl onto the couch or bed, and then be able to climb onto a human. 

As a person brushes by, the tick grabs onto a person’s shoe, pants, skin, or other clothing, then crawls to a safe spot on the body before it uses its mouth to “sink" into your skin. Ostfeld says, “They like those tucked-away places where the skin is soft and where they can hide without being detected,” he adds, mentioning the backs of the knees, the armpits, the back of the neck, and the groin as favorite locations.

Once a tick attaches itself to its host (a person or other animal) it feeds on blood for several days—up to 10 days in some instances. Then, it drops off the body on its own. 

Common Tick Bite Areas

Once on the body, ticks prefer a warm area that is moist (such as the armpit or the hair). A study conducted by German researcher Dr. Anja Reichert aimed to discover the most common areas that ticks bite on the human body. The research team analyzed 10,000 tick bites and discovered:

• Tick bites are possible anywhere on the body.
• The groin area, buttocks, and armpits were reported as areas of slightly above average frequency of tick bites in adults and kids.
•  In children, most bites from ticks were found on the head and neck, but in adults very few bites were documented on the head.
• In adults and children, the back of the knee was reported as a "hot spot" where ticks frequently bite.
• The chest and abdomen were favored areas that ticks were found to bite on the front side of the body.
• For boys and men, the groin area was a popular site for ticks to bite.

The study found that ticks can bite anywhere, so if a person has been in the woods, it’s important to inspect all parts of the body and remove any ticks that are found as soon as possible.

Detecting Tick Bites

Identifying tick bites may be more difficult than detecting other types of parasites or insects—such as mosquitos—that cause itching or skin irritation. Biting insects usually introduce saliva containing proteins that keep the bite wound from clotting. This results in itching, swelling, redness, and irritation, alerting the host that a bite has occurred. 

Ticks, however, have immunosuppressants that work to repress any reaction. This means that the only way to detect a tick is to spot one crawling on the skin or see its bite once the tick has dropped off. In the case of the black-legged tick, it’s so small that it is difficult to see them. Even in the adult stage, many ticks are nearly impossible to spot because of their small size. One way to identify ticks is to run your hands through the body to palpate (feel) for small, hard nodules on the skin. 

Identifying Tick Bites After the Tick Drops Off

Once the tick drops off, there is sometimes (but not always) a red welt, or an itchy lesion left behind—the lesion can vary in size and appearance. If the bite did not transfer any type of tickborne disease, the affected area will look like a mosquito bite and will fade away quickly. 

Symptoms of Tick Bites

If a tick bite does not result in transmission of a disease, usually there are no lasting symptoms. However, some people are allergic to tick bites and may have symptoms such as:

• Swelling or pain at the site of the tick bite
• A burning sensation
• A rash or blisters
• Difficulty breathing (indicated a severe allergic reaction that requires emergency medical intervention)

Signs of a Tickborne Infection

A tick-borne infection, such as Lyme disease or Rocky Mountain spotted fever, will cause various symptoms (depending on the disease). Symptoms begin within a few days to a few weeks after the tick bite occurs. Symptoms of a tickborne infection may include:

• A lesion that lingers more than a few days
• A large bull’s eye-shaped skin lesion (a red welt surrounded by one or more rings of inflamed skin)—this is a hallmark sign of Lyme disease

• Fever and chills
• Nausea
• Weakness
• Headache
• Neck stiffness
• Swollen lymph nodes
• Aches and pains, fatigue and muscle aches (joint pain may indicate Lyme disease)
• A rash that may occur from three to 30 days after being bitten by a tick
• Various types of skin rashes (distinctive in specific types of tickborne diseases such as Rocky Mountain spotted fever, which can result in flat, pink macules or round shaped raised spots on the wrists, forearms, or ankles)
• Other skin rashes—such as those seen in ehrlichiosis—that may include a petechial rash (pinpoint round spots that appear in clusters on the skin)
• A rash that covers the entire body
• Skin ulcers where the tick bite occurred (in tularemia, the ulcer is accompanied by swelling in the armpit or groin area)

Removing a Tick

Before Lyme disease can be transmitted via a tick bite, the tick must be attached for at least 36 hours. However, other diseases can be passed to the host within a few hours (or less). 

A visit to the healthcare provider will ensure that a tick is removed completely, but it may not be feasible to get an appointment right away. Therefore, it may be important to remove the tick yourself. There are tick removal tools commercially available, but, the most important thing to remember is to remove the tick as soon as possible.  

“Grab the tick’s mouthparts as close to the skin as possible and pull straight out,” Ostfeld says. Don’t worry if you squish the tick or leave a small speck of black in your skin. “That’s not a big deal. Swab it with alcohol or something else to prevent infection,” Ostfeld adds. The longer the tick is attached, the more likely it is to transfer a tick-borne illness.

Despite what people may commonly believe, mashing the tick or killing it during the extraction process will not cause it to excrete more fluid into the host. After the tick is removed, clean the area with alcohol to disinfect the area. Place the tick in the freezer in a sealed container or plastic bag—if symptoms occur, the healthcare provider will want to visually inspect the tick.

When to See a Healthcare Provider

It’s important to see a healthcare provider or healthcare provider as soon as possible after a tick bite when the following occurs:

• A bulls-eye type rash occurs at the tick bite site
• The rash from a tick bite or unknown source is bigger than the localized (in one area) red raised region
• Flu-like symptoms accompany a tick bite (or unknown source of a bite) such as muscle aches, fever, or chills within 10 days of the tick bite
• You are unable to remove the entire tick (including the head)
• The rash (which usually appears within three to 14 days of getting bitten by a tick) gets bigger
• The bite site appears infected (reddened, swollen, or oozing pus)
• You think you may have been bitten by a black-legged tick (deer tick)

According to Mayo Clinic, “Consult your healthcare provider if signs and symptoms disappear because you may still be at risk of the disease [Lyme or other tick-borne illnesses]. Your risk of contracting a disease from a tick bite depends on where you live or travel to, how much time you spend outside in woody and grassy areas, and how well you protect yourself.”

When to Seek Emergency Care

Call 911 or visit a local emergency medical facility if symptoms include:

• A severe headache
• Problems breathing
• Paralysis
• Heart palpitations

Treatment 

The treatment for a tick bite that is thought to result in being exposed to a tick-borne illness is antibiotics. Antibiotics may be given by mouth or possibly intravenously. A single dose of antibiotics may be given after a black-legged tick (deer tick) bite to prevent Lyme disease in areas where Lyme disease is highly endemic (regularly found within a specific area). 

Other types of tick-borne illnesses are not treated prophylactically (before an illness occurs) with antibiotics.

Prevention

The best method of preventing tick-borne illnesses is to stay away from outdoor habitats where ticks live and breed—particularly during the spring and summer seasons. Other preventative measures, when you do go outdoors, include:

• Spraying a chemical repellent that has DEET, permethrin, or picaridin
• Wearing light-colored protective clothing
• Tucking pant legs into socks.
• Wearing a hat to cover the head
• Performing self-checks (and checking kids and pets) to inspect for ticks daily, then removing any ticks right away
• Ensuring pets that go outside are treated regularly with a veterinarian-approved tick preventative agent