EVERYTHING YOU HAVE ALWAYS WANTED TO KNOW ABOUT TICKS

EVERYTHING YOU HAVE ALWAYS WANTED TO KNOW ABOUT TICKS!

At one time or another most people will experience the aggravation of tick bites. Knowledge of tick biology and habitats, as well as methods of tick control, can help you avoid this problem.

Most ticks are parasites of warm-blooded animals. Their bites are not only annoying and painful but may result in localized skin inflammation, secondary infection and possible introduction of disease-causing microorganisms.

Ticks are not insects but are closely related to mites, spiders and scorpions. Adult ticks have eight legs, while adult insects have only six. Also, the tick's body is fused into a single region instead of having the head, thoracic and abdominal regions typical of insects.

Ticks are grouped into two families: 1) the "hard ticks" (Ixodidae), which have a hard smooth skin and an apparent head; and 2) the "soft ticks" (Argasidae) which have a tough, leathery, pitted skin and no distinguishable head. Both groups contain species that attack humans and animals.

LIFE CYCLE

Ticks have four developmental stages: egg, six-legged larva, one or more eight-legged nymphs and adult. Hard ticks usually mate on the host animal. The female then drops to the ground and deposits from 3,000 to 6,000 eggs, which hatch into larvae or "seed ticks." Larvae climb nearby vegetation where they collect in large numbers while waiting for small rodents or other vertebrates to pass within reach. After a blood meal on the host, the engorged larvae drop to the ground. shed their skins (molt) and emerge as nymphs. Like larvae, the nymphs await the passage of a host, engorge themselves with blood, drop to the ground, molt and become adults. Adult ticks seek host animals and after engorgement, mate.

Male hard ticks usually mate with one or more females and then die, although some may live for several months. Females die soon after depositing their eggs in protected habitats on the ground. The life cycle requires from as little as 2 months to more than 2 years, depending on the species.

This life cycle is characteristic of tick species which commonly infest humans and their pets in Texas . However, some species feed as larvae, nymphs and adults on only one host during the life cycle.

TICKS AND DISEASE

When feeding, the tick makes a small incision in the skin of the host and inserts barbed piercing mouthparts to remove the blood. Most species cause little or no pain to their hosts at the time of feeding, but some, such as the lone star tick, cause a painful wound. Ticks can transmit diseases by infecting hosts with microorgranisms carried on their mouthparts or in salivary fluids.

Many disorders and diseases can be traced to tick bites, including 1) dermatosis, or inflammation, itching and swelling at the site of the bite; 2) envenomization, or inoculation of toxic fluids; and 3) exsanguination, or anemia resulting from the loss of large amounts of blood because of a severe tick infestation.

The American dog tick is also known to cause paralysis in dogs and children where ticks attach at the base of the skull or along the spinal column. Paralysis is caused by a toxic secretion produced by the feeding tick. When the tick is removed, recovery is rapid, usually within 8 hours. Sensitized animals may become paralyzed by tick attachment anywhere on the body.

Also known as tick typhus, Rocky Mountain spotted fever is caused by a bacteria-like microorganism, Rickettsia rickettsii. Rocky Mountain spotted fever rickettsiae are acquired by an American dog tick when it takes a blood meal from an infected animals. These bacteria are not harmful to most wild and domestic animals, but they are extremely pathogenic to humans and dogs. Rocky Mountain spotted fever is normally a disease of wild animals, but people can be infected while camping or hiking in tick-infested areas if they are bitten by an infected tick. In addition, pets may carry an infected tick into living areas. The disease organisms can also be passed through the egg of an infected tick and from stage to stage in the life cycle. Fortunately, only a small percentage of American dog ticks found in nature are infected.

Symptoms of Rocky Mountain spotted fever include headache, fever, chills, aches, pains, and sometimes nausea. These symptoms are usually accompanied by a rash that starts on the wrists and ankles. Because Rocky Mountain spotted fever is easily cured with antibiotics, a person exhibiting any of these symptoms 2 to 14 days after a tick bite should consult a physician at once. If left untreated, Rocky Mountain spotted fever can cause death. Lone star and American dog ticks are carriers of Rocky Mountain spotted fever and tularemia.

Lyme disease is transmitted primarily, if not exclusively, by ticks. The primary vector is the deer tick (Ixodes dammini). The American dog tick and the brown dog tick are not considered important vectors of Lyme disease. Lyme disease is a serious problem in the Northeast and Great Lakes regions of the U.S.

However, in 1989 there were 82 confirmed cases of lyme disease reported by the Texas Department of Health, with the majority of these cases being reported from the eastern and northeastern portions of the state. The deer tick is not prevalent in Florida, but species that are close relatives and are capable of transmitting Lyme disease are common throughout the state. When in habitats likely to be infested with ticks, precautions should be taken to prevent lyme disease.

Humans, particularly those who work or vacation in heavily tick infested areas, who experience the onset of symptoms resembling a febrile (fever-like) disease and recall being bitten by a tick 10 to 14 days earlier should mention this association to their physician. Brown dog ticks carry diseases to humans and animals in Africa and the Mediterranean region but are not known to transmit human disease in the U.S. but are capable of transmitting canine piroplasmosis among dogs.

FREQUENTLY ASKED QUESTIONS ABOUT TICKS AND DISEASE

Few pests evoke as many questions from people as ticks. Besides their repulsive appearance, ticks are vectors of potentially debilitating and life-threatening diseases. Lyme disease, in particular, has attracted national attention and is now the number one arthropod-borne disease in the United States. Although Lyme disease is more prevalent in eastern and midwestern states, media coverage has prompted many questions and concerns from citizens.

What is Lyme disease?

While dog ticks are not healthy for your dog, it is the Deer Tick, the Lone Star Tick and the Westerm Black-Legged Tick that carry Lyme Disease. You can easily see dog ticks, but those three are tough to see.

Lyme disease is a potentially serious bacterial infection, transmitted through the bite of certain species of ticks. The disease affects humans and a wide range of animals including pets and livestock. Lyme disease manifests itself in many ways and if left untreated may progress through several stages. The disease is difficult to diagnose clinically because early symptoms often mimic the flu (i.e., fatigue, headache, stiffness or pain in neck, muscles or joints, fever, or swollen glands). The most definitive early symptom is a gradually expanding circular or oval-shaped red rash. This rash only develops in about 70% of infected individuals, however, and may be overlooked.

Persons who experience any of the above-mentioned symptoms after being bitten by a tick (or having spent time in tick-infested areas), should consult a physician immediately. Lyme disease can be treated successfully in these early stages with antibiotics. As the disease progresses, it becomes more difficult to manage. Later symptoms of infection may include heart and neurological disorders, and arthritis.

How can I tell if the tick I just removed is capable of transmitting Lyme disease?

The American dog tick and the lone star tick. Neither has been shown to transmit Lyme disease. The adults of these species are comparatively large, being about the size of a pencil eraser. Adult ticks of the variety most often responsible for transmitting Lyme disease (e.g., Ixodes dammini), are considerably smaller -- adults are about the size of the head of a pin. Therefore, if the tick that was found is pencil eraser-size or larger, it's probably an American dog tick or lone star tick and, consequently, not a vector of Lyme disease.

Definitive tick identification, however, requires the expertise of an entomologist. Immature stages of lone star and Ixodes ticks are both extremely small (about the size of a sesame seed), and are easily mistaken for one another. The UK Entomology Department will identify ticks at no charge. Specimens should be sent to Dr. Greg Burg in alcohol-filled vials accompanied by the date and county from which the tick was collected.

It should be noted that ticks capable of transmitting Lyme disease must be attached for at least 24 hours for infection to occur. A person cannot become infected simply by having a tick crawl over their skin or clothing.

TICK REMOVAL

Because tick movements and bites are seldom felt, careful and frequent examination for ticks on the body and clothing is imperative. Early removal is important since many disease organisms are not transferred until the tick has fed 2 to 8 hours. Always remove the tick with its mouthparts intact. Hasty removal of an attached tick can break off the mouthparts. Mouthparts left in the skin may cause secondary infection. To relax tick mouthparts for easy removal, touch the tick with a hot needle or a few drops of camphor, alcohol, turpentine, kerosene or chloroform. The best method is to grasp the tick firmly with tweezers and remove it with a slow, steady pull. Avoid touching the tick vvith your bare hands. If an infected tick is crushed between the fingernails the organism responsible for Rocky Mountain spotted fever may enter through a cut or abrasion.

Should you find a tick attached to the skin, the following procedures should be used for removal:

Use blunt tweezers or disposable gloves to handle the tick. If fingers must be used, shield them with a tissue or paper towel. Infectious agents may be picked up through mucous membranes or breaks in the skin by handling infected ticks. This is especially important for people who "detick" pets or other domestic animals, as ticks infesting dogs and other domestic animals can carry Lyme disease or several other diseases capable of infecting humans.

Grasp the tick as close to the skin surface as possible. This reduces the possibility of the head detaching from the body upon removal.

Pull the tick out straight out with a steady, even pressure. Do not twist or jerk the tick as this may cause the mouthparts to break off and remain in the skin, increasing the chances of infection. Continue the steady pressure even if the tick does not release immediately-it may take a minute or so of pulling to cause the tick to release.

After removing the tick, thoroughly disinfect the bite site and wash your hands with soap and water. Home remedies such as applying vaseline, grease, or a hot match to the rear of the tick are not recommended. These practices cause the tick to salivate and can actually increase the chance of getting the disease.

After removing the tick, you may wish to preserve it in alcohol-plain old rubbing alcohol will do. Be sure to label the container with information about the time and place where the tick bite occurred. This activity will help you to remember details of the incident if the rash or other symptoms associated with Lyme disease appear later. This information will also be of help to a physician in diagnosing the illness.

Fortunately, prompt treatment with antibiotics is very effective in curing Lyme and other tick-borne diseases, but most people agree that protecting yourself from tick bites in the first place is the best approach.

TICK CONTROL

Protection from Ticks

To obtain some degree of protection against ticks, keep clothing buttoned, shirt tails inside trousers and trouser legs inside tops of socks. A ring of masking tape with the sticky side out placed around the top of boots will trap ticks that are ascending to look for a site to attack. Do not sit on the ground or on logs in brushy areas.

Persons who must be in areas suspected of supporting infestations should examine their clothing, body and hair at least twice daily to remove ticks promptly.

Clear or burn brush along trails and cut weeds and grass in recreation areas. In residential areas, maintain closely cut and well-kept lawns to help control both ticks and their small rodent hosts.

Repellents containing diethyl-m-tolumide, dimethyl phthalate, dimethyl carbate or ethyl hexandiol will protect exposed skin but will not stop ticks from crawling under clothing to reach untreated portions of the body. Applying these materials to the entire body might prevent tick bites for a while, but such extensive treatments often are impractical and may be hazardous to health. Permanone, a tick repellent containing a synthetic pyrethrin, may be applied to clothing (do not allow skin contact). Treatment with this product may provide protection for a day or longer.

Chemical Control

If a tick infestation occurs, treat the home, yard and pets at the same time. Examine dogs and cats frequently for ticks. Heavy infestations on pets should be handled by a veterinarian.

Light infestations in buildings usually can be controlled with a household residual spray. Apply the insecticides only as light, spot treatments to areas where ticks are found or suspected to be hiding. DO NOT USE THESE CHEMICALS FOR TREATING PETS. Treatment around baseboards, window and door casings, wallcracks and in pet sleeping quarters is necessary. To control severe infestation in the home, remove the pet from the house and make repeated applications of approved insecticides at 2- to 4-week intervals. Select a spray that does not have an objectionable odor and will not stain paints, wall paper, tile or rugs.

Tick control in home lawns and other vegetated areas usually can be obtained with residual sprays or dusts. Give particular attention to spray applications around building foundations and along roadsides, animal trails and paths used by people.

The USER always is responsible for the effects of pesticide residues on his own premises, as well as problems caused by drift from his property to that of others. Always read and follow carefully all instructions on the product control.

COMMON TICK SPECIES IN THE SOUTHERN UNITED STATES

	American Dog *Dermacentor varibilis*	Black Legged *Ixodes scapularis*	Brown Dog *Rhipicephalus sanguineus*	Lone Star *Amblyomma americanum*
Alabama	X	X	X	X
Arkansas	X	X	X	X
Florida	X	X	X	X
Georgia	X	X	X	X
Kentucky	X	X	X	X
Louisana	X	X	X	X
Mississippi	X	X	X	X
North Carolina	X	X	X	X
Oklahoma	X	X	X	X
South Carolina	X	X	X	X
Tennessee	X	X	X	X
Texas	X	X	X	X
Virginia	X	X	X	X

AMERICAN DOG TICK

AMERICAN DOG TICK FEMALE AMERICAN DOG TICK MALE

Disease Transmission of this tick: Rocky Mountain Spotted Fever Tularemia

The American dog tick attacks a wide variety of hosts, including humans, but rarely infests homes. Adults are chestnut brown with white spots or streaks on their backs. Unfed adults are about l/8-inch long. Engorged females become slate gray and may expand to a length of l/2-inch. Larvae and nymphs feed mostly on small rodents, while adults feed on dogs, cattle, other animals and humans. These ticks are widely distributed over the eastern two-thirds of Texas but are most abundant in coastal and other humid areas. They are attracted by the scent of animals, and humans most often encounter them near roads, paths, trails and recreational areas. Although present the year round, American dog ticks are usually most numerous in the spring.

The female dog tick lays 4000-6500 eggs and then dies. The eggs hatch into seed ticks in 36-57 days. The unfed larvae crawl in search of a host and can live 540 days without food. When they find a small rodent, the larvae attach and feed for approximately 5 days. The larvae then drop off the host and molt to the nymphal stage. The nymphs crawl in search of a rodent host, attach to a suitable host, and engorge with blood in 3-11 days. Nymphs can live without food for up to 584 days.

Adults crawl in search of dogs or large animals for a blood meal. Adults can live for up to 2 years without food. American dog tick adults and many other species can be found along roads, paths, and trails, on grass, and on other low vegetation in a "waiting position." As an animal passes by, the tick will grasp it firmly and soon start feeding. The males remain on the host for an indefinite period of time alternately feeding and mating. The females feed, mate, become engorged, and then drop off to lay their eggs.

The American dog tick requires from 3 months to 3 years to complete a life cycle. It is typically an outdoor tick and is dependent on climatic and environmental conditions for its eggs to hatch.

LONE STAR TICK

Lone STAR TICK FEMALE LONE START TICK MALE

Adult lone star ticks are various shades of brown or tan. Females have single silvery-white spots on their backs and males have scattered white spots. Unfed adults are about l/3-inch long, but after feeding females may be l/2-inch long. Larvae and nymphs parasitize small wild animals, birds and rodents, while adults feed on larger animals. All three stages will bite humans. These ticks live in wooded and brushy areas of Texas and are most numerous in underbrush along creeks and river bottoms and near animal resting places. Lone star ticks are present throughout the year, but peak adult and nymphal populations may occur from March to May. A second nymphal peak may occur again inJuly or August, while peak larval activity is reached in mid-June or July

BROWN DOG TICK

BROWN DOG TICK FEMALE BROWN DOG TICK MALE

Disease Transmission of this tick: Canine ehrlichiosis, Canine bebesiosis

ENGORED BROWN DOG TICK

The brown dog tick rarely bites humans, but infestations are frequently found on dogs and in the home.

Adults are reddish-brown. Unfed adults are l/8-to 3/16-inch long. The adult female lays a mass of 1000-3000 eggs after engorging on a dog's blood. Engorged females are about l/2-inch long. They feed almost exclusively on dogs, where they attach to the ears and between the toes. They are widely distributed in Texas and rarely attack man.

The eggs hatch in 19-60 days into a six-legged, small seed tick. The seed tick takes a blood meal from dogs when they are available. The larvae are so small they won't be noticed on the dog unless a number are together. The seed tick remains attached for 3-6 days, turns bluish in color, and then drops to the floor. After dropping from the host, the seed tick hides for 6-23 days before molting

into an eight-legged, reddish-brown nymph. It is now ready for another blood meal and again seeks a dog host.

The nymphs attach to dogs, drop off, and molt to the adult in 12-29 days. As a reddish-brown adult, it again seeks a blood meal, becomes engorged, and is bluish in color, reaching about 1/3 inch in length.

Unengorged larvae, nymphs and adults may live for long periods of time without a blood meal. Adults have been known to live for as long as 200 days without a blood meal.

Brown dog ticks become a problem in and around human habitation or dog kennels when ticks fall off infested dogs as engorged larvae, nymphs or adults. Inside the home, the ticks hide behind baseboards, window casings, window curtains, ceiling and picture moldings, bookcases and cabinets, as well as inside upholstered furniture and under the edges of rugs. Outdoors, they hide near building foundations, in crevices between porch floorings and sidings and beneath porches.

BLACK LEGGED TICK (formally known as the Deer Tick)

Black Legged Tick FEMALE BLACK LEGGED TICK MALE

Disease Transmission of this tick: Primary vector of lyme disease
Human granulocytic ehrlichiosis

The black-legged tick, Ixodes scapularis, formerly known as the Deer Tick, Ixodes dammini, is the main vector of Lyme disease. Eight specimens have been found in Ohio in spite of more than 489 human cases of this disease reported since 1984. Tick exposure and travel histories suggest out-of-state exposure in about half the cases. Lyme disease symptoms, caused by coiled spirochete bacteria (Borrelia burgdorferi), develop within 3 to 32 days and include an initial reddish skin rash at the tick bite site, commonly expanding to many inches in diameter and appearing like a ring or bull's-eye. The rash fades, with or without treatment, after a few weeks (not all infected people develop this rash). Early symptoms include flu-like chills, fever, headache, dizziness, fatigue, joint ache, and a stiff neck. Subsequent symptom progression involves swelling and pain in the joints, especially the knees, that can lead to chronic arthritis, sometimes a year after the bite. Less common symptoms include heart arrythmia, weakness in legs, facial paralysis, and numbness. Antibiotic therapy is most successful when treatments begin during early stages of the disease development. One other species is believed to be able to transmit Lyme Disease to humans in the United States: I. pacificus in the west coast states.

Identification

The larval stage of the black-legged tick is about the size of a poppy seed, flat, six-legged, and nearly translucent, making it extremely difficult to see. The nymphal stage, most responsible for disease transmission to humans, is about the size of a flat pinhead or sesame seed, eight-legged and translucent with a slight tinge of gray, also making it very difficult to see. The adults are variable in size. Males are about 2 to 2.5 millimeters in length and the females are larger, about 3 to 3.5 millimeters in length. Both sexes are dark chocolate brown in

color, but the hind half of the female has a distinctly reddish or orangish coloration. Like all hard-bodied ticks, the dorsal (top-surface) of the adult male is largely covered by a scutum (tough plate), while in the female the scutum covers only the anterior (front) part of the top-surface. (See illustration of male and engorged female.) The reddish posterior portion of the female can expand greatly while filling with blood. The larva, the nymph, and the adult female can enlarge to 2 to 3 times their normal size after they have fed on blood. When fed, they may appear gray or grape-colored, depending upon the stage of digestion of the blood meal. There are many other species of Ixodes ticks in the United States. Only an expert can identify them to species.

Life Cycle and Habits

The black-legged tick in the eastern United States is a three-host tick that has a two-year life cycle. Eggs deposited in the spring hatch into six-legged larval ticks (most occur in late summer), which attach to small mammals (white-footed mouse, voles, chipmunks) or birds to obtain their first blood meal. These larvae overwinter, then molt to an eight-legged nymphal stage. Nymphs attach to small to medium size animals (mice, dogs, raccoons, possums, gray squirrels) and humans. It is this small nymphal stage that transmits the Lyme disease agent to humans. Nymphs molt to the adult stage the same summer, then crawl to a large mammal, most commonly white-tailed deer. After engorging, they mate on or off the host and later lay eggs. They are commonly found in and near wooded areas.

Lyme Disease History

The disease was first identified in Lyme, Connecticut in 1975 with the heaviest concentrations now recognized in the Northeast, upper Midwest, and along the northern West coast. Eight states have recorded the highest numbers of cases. These are Pennsylvania, New York, New Jersey, Wisconsin, Minnesota, Massachusetts, Connecticut, and Rhode Island. About 10,000 human cases are diagnosed annually. Lyme disease is also found abroad in Germany and Scandinavia, as well as China, and Asia to Australia.

Migratory birds may partially account for the spread of this disease since larval and nymphal black-legged ticks often feed on ground-feeding birds. The active months for human infection are May to August. Peak months are June and July.

Lyme disease symptoms resemble many other diseases, like spirochete-caused syphilis. Lyme disease has been called the 'great imitator' since blood tests do not always confirm Lyme disease or rule it out. Lyme disease long-term effects can be arthritis, facial paralysis, meningitis, abnormal heartbeat, myocarditis, depression, memory loss, numbness, and impaired hearing and vision. Lyme is not usually a fatal disease, but can be debilitating, emotionally as well as physically. Unfortunately, vaccines for people won't be on the market for some time. A vaccine for dogs is available.

Control Measures

One possible explanation for the rise of Lyme disease is that populations of deer, raccoon, opossum, birds, and other wildlife have rapidly expanded in the last few years, and human proximity to these animals has increased as suburban development has encroached on woodlands.

Prevention

Black-legged ticks are found mostly near or in woods. When camping or hiking in woody or brushy areas, try to stick to the middle of the trail, if possible, avoiding potentially tick-infested areas. Wear long-sleeve shirts and long trousers (not shorts) and tuck your pant bottoms into tops of socks or boots. Wearing light colored clothing of tightly woven fabrics makes it easier to find crawling ticks. Check often for ticks especially after leaving the woods. Use insect repellent containing moderate (20 to 50 percent) concentrations of N,N-Diethyl-meta-toluamide (DEET) on the skin according to label directions. Do not use indiscriminately as severe allergies can develop in certain persons. Permethrin (Permanone) may also be sprayed on clothing, especially pant legs and socks. This product is not to be applied to skin. It is available from Southern Mill Creek Products of Ohio, Inc., 800/321-3294 (Ohio) or 800/929-PEST (outside of Ohio). Also, other pesticide distributors may have Permanone commercially available.

Common sites of attachment include the underarms, the groin, behind the knee, and the nape of the neck. Examine children often, paying special attention to the head, neck and ears. Teach them to avoid tall grass and low brush. Keep dogs and cats tied or restricted to a mowed area. If pets are allowed to roam free, check them daily especially if allowed indoors. Allowing pets to roam freely is not recommended since free-roaming pets help perpetuate tick problems, and pets also can be infected with Lyme disease and Rocky Mountain Spotted fever. Ticks may hitch a ride and fall off in the house. Do not let animals rest on furniture and don't sleep with them. Amitraz collars labelled for dogs only are effective on ticks. After 24 hours, 95 percent of attached ticks become detached.

Tick Removal

Look for a freckle that moves. Remember that the black-legged tick is small. The nymphs are about the size of a pinhead. Prompt removal reduces the chance of infection. The tick deposits the spirochetes in a convenient capillary only after feeding for 12 to 24 hours. People usually do not realize that the meal is underway.

· Use tweezers or shield your fingers with a paper towel or tissue paper. Grasp the tick as close to the skin as possible and, with steady pressure, pull straight out to remove the entire tick. (Never use bare hands.)

· Never jerk or twist the tick since the mouthparts may be left in the skin. Do not crush or puncture the tick during removal. Never use a hot match or cigarette since the tick may burst, spilling body fluids and disease organisms on the skin.

· After tick removal, thoroughly disinfect the bite site and wash hands with hot soapy water.

· Save ticks for identification. Place ticks in a stoppered vial and send to the Vector-borne Disease Program (VBDP), c/o Tick Testing Lab, Ohio Department of Health, 900 Freeway Drive North, Columbus, Ohio 43229. Telephone 614/752-1029, Fax 614/752-1391. Live deer ticks may be used for study to aid in the diagnosis of Lyme Disease. Dead ticks are best preserved in 70 percent rubbing alcohol. Do not handle ticks with bare hands. Tick mailers are available by calling or writing the VBDP.