Ticks : Environmental Health : NYC DOHMH

The New York City Department of Health and Mental Hygiene


	Environmental Health Services Ticks What are ticks? Ticks are Arachnids, a class of animals that also includes spiders, mites, chiggers and scorpions. All ticks are wingless and have four pairs of legs, each containing a small suction cup. Ticks are external parasites, meaning that they require a host for food and/or shelter. For ticks, an animal (human or otherwise) serves as the host. Ticks are divided into 2 major groups: soft ticks (Family: Argasidae) and hard ticks (Family: Ixodidae). Soft ticks are tough and leathery looking; they have more than one young (nymph) stage; and their sexes cannot be differentiated. Though soft ticks are not vectors of many arboviruses (viruses transmitted by Arthropods), they do act as vectors of African swine fever virus among pigs. Hard ticks posses a hard dorsal shield that is small in females and covers the whole male. They have only one larval and one young (nymph) stage. They also transmit tick-borne relapsing fever. Hard ticks are carriers of many diseases. What ticks are present in New York City and what diseases do they transmit? Three types of hard ticks are commonly found in New York City. *American dog ticks (Dermacentor variablis)* are about 1/8" long and are common in New York City's parks. They are dark brown with scattered patterns of white on the body below the head. Females are larger then males. They are the vector for Rocky Mountain spotted fever and tick paralysis. Deer ticks, also referred to as *eastern-blacklegged ticks (Ixodes scapularis), are about 1/3" long and commonly occur in the northeastern and mid-western United States. Females are larger then males and have a red body. Males are dark brown/black. They are the vector for an array of diseases, like Lyme disease, human granulocytic ehrlichiosis, babesiosis, and tick paralysis. They are sparsely found in New York City, but are abundant throughout Westchester County, Nassau County, Suffolk County and many counties in upstate New York. Lone star ticks (Amblyomma americanum)* are about 1/3" long, and are rarely seen in New York City, but are common in the southeastern and south-central states. Females are mostly brown/beige with a white spot in the middle of the body. Males have scattered spots or streaks along the body. They are the vector for human monocytic ehrlichiosis, tick paralysis, and Southern Tick Associated Rash Illness (STARI), which occurs predominantly in the southeastern/south-central areas of the United States. What is the tick life cycle? The life cycle of a hard tick consists of four stages: egg, larva, nymph, and adult. The lifespan of the average tick is about two years. In order for ticks to survive, grow, and reproduce, they take frequent blood meals from a host. To obtain blood, the tick will attach to the host by inserting its mouthparts into the skin. A hard tick may remain embedded in the skin for up to a week or until it is engorged (swollen) with blood. How do ticks transmit diseases? Ticks transmit diseases while feeding on a host's blood. An infected tick can transmit the disease pathogen (disease-causing agent), through the saliva and the gut contents. The infection process begins when a hard tick nymph takes a blood meal from an animal host (e.g., field mouse), which may also be a reservoir for any number of pathogens. After becoming fully engorged with blood, it falls off the host. Eventually the tick molts (transforms) into an adult tick. If the tick is a female, it must find another host and take a blood meal in order to mature its eggs. Male ticks only feed intermittently. After feeding from a host that was a reservoir for pathogens, a tick is capable of injecting that pathogen into the blood stream of its next host. What is the most common tick-borne disease in New York City? The most common tick-borne disease in New York City and across the United States is Lyme disease, which is caused by a spiral shaped bacterium, Borrelia burgdorferi. This can be attributed to the vast geographical distribution of the blacklegged deer tick and the western-blacklegged tick. What are the symptoms of Lyme disease? The initial symptoms of Lyme disease can be difficult to diagnose. The appearance of a red rash or bull's eye shaped rash at the bite site are both positive clinical signs of Lyme disease in humans. Other symptoms include, but are not limited to, multiple rashes on body, fatigue, headache, stiff neck, muscle and/or joint pain, fever, swollen lymph glands and flu-like symptoms. If Lyme disease is left unrecognized or untreated the symptoms will progress. In some cases chronic ailments may occur. The later symptoms of Lyme disease include, but are not limited to, extreme fatigue, numbness/tingling of the extremities, arthritis, heart problems and neurological disorders, such as dizziness and disorientation. Loss of pregnancy can also occur. What should I do if I think I have Lyme disease? If you think a deer tick has bitten you or that you have Lyme disease, contact your medical provider immediately. Lyme disease is treatable with antibiotics. Also, if you removed (see 'What is the best way to remove a tick?') and saved the tick, bring it with you for a more accurate diagnosis. What is Rocky Mountain spotted fever and what are its symptoms? Rocky Mountain spotted fever is an infection caused by a bacterium, Rickettsia rickettsii. The initial symptoms of Rocky Mountain spotted fever include, but are not limited to, a sudden onset of fever, nausea and vomiting, severe headache, muscle aches and pains, and loss of appetite. Later, a spotted rash usually appears on the forearms, legs, and/or ankles, accompanied by joint pain, abdominal cramps and diarrhea. What should I do if I think I have Rocky Mountain spotted fever? Immediately contact your medical provider. The treatment regimen is a 5-10 day course of antibiotics. If you removed and saved the tick, bring it with you for a more accurate diagnosis. Most people who contract Rocky Mountain spotted fever become immune to the disease. What are the causes and symptoms of human granulocytic ehrlichiosis and human monocytic ehrlichiosis? An Ehrlichia-like bacterium, transmitted by the deer tick, causes human granulocytic ehrlichiosis. The bacteria Ehrlichia chaffeensis, which is transmitted by the lone star tick, causes human monocyclic ehrlichiosis. Symptoms of both diseases are the same, and include: fever, headaches, muscle aches, nausea and /or vomiting, disorientation and joint pain. What are the treatments for human granulocytic ehrlichiosis and human monocytic ehrlichiosis? If you become sick after a tick bite, immediately contact your medical provider for treatment, a 7-10 day course of antibiotics. What is tick paralysis and what are its symptoms? Tick paralysis occurs when an engorged and egg-bearing female tick produces a neurotoxin in her salivary glands while attached to the host. It is mostly found among young children. The symptoms of tick paralysis include fatigue and numbness in the arms and legs. As time progresses, paralysis of the extremities occurs, followed by paralysis of the tongue and face. More severe symptoms include convulsions and respiratory failure. Once the tick is removed, the symptoms will vanish almost immediately. What is the treatment for tick paralysis? The only treatment for tick paralysis is to remove the tick. If symptoms persist, contact a physician immediately. If possible, keep the tick and bring it to the physician for proper identification. What is the best way to remove a tick? If a tick is crawling on you, remove the tick and discard immediately. If the tick is embedded in the skin, follow these steps: Using a pair of fine pointed tweezers, grab a hold of the area closest to the skin. Do not grab the body of the tick, as separating it from embedded mouthparts may cause secondary infection. Gently pull outward and try to remove the whole tick carefully. After removing the tick, wipe the area with alcohol and clean hands with soap and water. If possible, place the tick in alcohol or in a plastic zip lock bag and store in the freezer for identification. If your physician suspects a tick-borne disease he/she may ask to see the tick. Contact your medical provider immediately if you think you've been bitten by a tick and/or have any signs or symptoms of a tick-borne disease. How can I prevent tick bites and lessen my change of contracting a tick-borne disease? • Wear light colored clothing while entering tick habitats, as it will be easier to notice ticks on your clothing; • Tuck pants into socks and shirts into pants to prevent any ticks from attaching to your skin. • Spray insect repellant containing DEET on your shoes, pants, etc. • Wear gloves while gardening because ticks generally live under the soil and in leaf litter. • When mowing the lawn, wear a hat, long pants, and shoes. Adult ticks crawl up branches and grass to grab onto a passing host. • Tie hair up or wear a hat while entering a tick habitat. • Thoroughly check yourself and children for ticks after outdoor activities, especially when you are in areas where ticks are common. Additional Information • Centers for Disease Control and Prevention Rocky Mountain Spotted Fever Babesia Infection Southern Tick-Associated Rash Illness • American Lyme Disease Foundation, Inc. • Lyme Disease Foundation: Photo gallery • American College of Physicians • Mayo Clinic • Rhode Island Department of Health • New York State Department of Health • National Institute of Health Photographs: Courtesy of the Lyme Disease Foundation