Ticks and Tick-Borne Diseases in Dogs

Ticks are found in nearly all parts of the country and are especially prevalent in spring and fall. Ticks are vectors for several diseases in dogs, including:

  • Rocky Mountain spotted fever
  • Canine ehrlichiosis
  • Canine babesiosis
  • Canine hepatozoonosis
  • Lyme disease

In the case of Lyme disease and Rocky Mountain spotted fever, these diseases can also spread to humans and cats. And ticks can carry different forms of ehrlichiosis, babesiosis, and hepatozoonosis that can affect humans and other animals.

The saliva of ticks can also produce an allergic hypersensitivity reaction and, in the case of the female wood tick, lone star tick, and Gulf Coast tick, a disease called tick paralysis. The most common ticks, such as the dog tick, have males about the size of a match head and females that expand to the size of a pea after a blood meal. Deer ticks are much smaller-about the size of a pinhead.

Ticks do not run and jump as fleas do, but scuttle around slowly. They climb up grass and plants and hold their legs up to sense passing hosts. When a warm-blooded animal walks by, the adult tick crawls onto them and begins feeding.

Ticks can fasten to any part of the dog's skin, but are commonly found around the ears, between the toes, and sometimes in the armpits. A severely infested dog may have hundreds of ticks all over her body. The ticks insert their mouths, attach to their prey, and engorge themselves with a blood meal. During feeding, tick saliva can get into the host's body and blood stream; this is how diseases are transmitted.

Males and females mate on the skin of the dog, after which the female takes a blood meal and then drops off to lay her eggs. This usually occurs 5 to 20 hours after the dog acquires the ticks. Thus, prompt removal of ticks is an effective method of preventing tick-borne diseases.

Ticks may drop off a dog and transfer to people, although this is not common. Once a tick starts feeding on a dog, it will feed until it is engorged and will not seek a second host.

Treatment: Always examine your dog after hiking in tick-infested areas. If you find only one or two ticks, the easiest thing to do is remove them. Keep in mind that the blood of ticks can be dangerous to people. Therefore, do not crush or squeeze a tick with your bare fingers. Before removing the tick, put on disposable rubber or plastic gloves.

Ticks that are not attached to the skin are easily removed with a pair of tweezers. There are also special tick removing devices that are widely available. Once removed, the tick can be killed by putting it in rubbing alcohol.

You must be careful if you find a tick with its head buried in the skin, because the head may detach and remain behind. Grasp the tick firmly with tweezers or a tick removal device, as close to the dog's body as possible without pinching her skin, and lift it off.

Use the tweezers to place the tick in a jar or plastic dish with a little alcohol, Seal it well and dispose of the container in an outdoor garbage can. Don't flush it down the toilet, because the tick will survive the trip and infect another animal. Wash the tweezers thoroughly with hot water and alcohol.

If the head or mouth parts remain embedded in the skin, redness and swelling is likely to occur at the site of the bite. In most cases, this reaction clears up in two to three days. A dab of antibiotic ointment will help prevent most skin infections. However, if it does not-or if the redness seems to be getting worse-consult your veterinarian.

If the dog has many ticks, treatment involves an insecticide dip containing natural or synthetic pyrethrins labeled for ticks, or an organophosphate dip such as Paramite. Be sure to eliminate all ticks from the dog's sleeping quarters.

Ticks can work their way deep into the ear canals. These ticks should be removed by a veterinarian.

Prevention: Ticks must attach for several hours before they can transmit diseases. Therefore, if you remove all ticks promptly after your dog has been running in the fields or woods, you can prevent many tick-borne infections.

Preventic tick collars containing amitraz are quite effective in controlling ticks. These collars are effective for up to three months, but should not be used on puppies under 12 weeks of age and should not be used on household dogs where young children may come in contact with the collar. Frontline, used to control fleas, kills or disables most ticks for up to 30 days following a single application. Consider using this product along with an amitraz tick collar during the tick season. Advantix is another topical product that can repel and kill some species of ticks.

This article is excerpted from “Dog Owner’s Home Veterinary Handbook” with permission from Wiley Publishing, Inc.