Tick Infestation and Tick Prevention in Dogs

Summary

Ticks are skin parasites; they live on the skin and eat the blood of their hosts. They can consume enough blood to make a host anemic. Some species of ticks have toxic saliva that can paralyze their hosts. Many tick species serve as vectors for infectious diseases as they transmit them from one host to the next. These tick-borne illnesses can affect a variety of mammalian hosts, including humans. 

A tick is a small arachnid with a flat, oval body. There are various species of ticks and their coloring can range from yellow, gray, to reddish-brown, to black. Ticks are found worldwide year-round. In North America, ticks are most active in spring and summer, with another spike in the fall.  

Ticks live and feed on a host until they are fully engorged, then they drop off. Ticks seldom infest a home (except for brown ticks), but can take up residence in the yard.

A dog’s skin and coat should be inspected regularly for the presence of ticks. If ticks are found, they must be removed and destroyed immediately. The presence of a tick on a dog is not a medical emergency, but removing the parasite from the dog’s body is essential to reduce the likelihood of transmission of tick-borne disease.

Tick control is a public health concern because ticks can transmit diseases to humans. It is recommended that all dogs stay on a veterinarian-approved form of tick prevention year round. In addition to medical preventatives, it is important to check a dog’s skin regularly for signs of infestation. 

A note about “natural” tick control products: an abundance of pesticide-free products claiming to kill, prevent, or repel ticks are available on the market. There are no natural products currently on the market backed by scientific evidence that supports their safety for use nor their efficacy in preventing or eliminating ticks.

Risk Factors

Since tick populations can be found all over the world, ticks may be found on a dog at any time, but especially during regional peaks in tick activity. Finding a tick on a dog is not an emergency, but it is an immediate call to action. 

The tick life cycle has four stages; egg, larva, nymph, and adult. Larvae and nymphs must eat before they can move onto the next stage. This means by the time the adult tick bites a dog, it has bitten at least two other animals. Any diseases carried by those animals can be transferred to the dog. 

It is important to note that a tick may feed on a dog and drop off without ever being discovered. Ensuring a dog is on a vet-approved external parasite control regimen will minimize the potential risk of disease transmission when a tick bite goes undetected.

Possible Causes

Ticks are ubiquitous in the environment. Tick infestation on a dog is caused by environmental exposure to tick habitats, such as wooded areas and long grasses. A large-scale infestation is preventable as long as the animal is kept on an up-to-date vet approved preventative tick medication program.

Main Symptoms

The presence of a tick on a dog is self evident. Symptoms resulting from tick bites can include:

• Irritation and itchy skin (pruritus) • Localized inflammation • Allergic hypersensitivity

• Secondary bacterial infection of the site of the bite and surrounding area

Detailed Characterization

Tick bites can directly cause illness in dogs: 

• Heavy tick burdens can result in enough blood loss to make the host anemic.

• Certain tick species have toxic saliva that can cause paralysis in their hosts (tick paralysis).

Ticks carry and transmit pathogens that cause diseases in a variety of mammalian hosts, including humans. There are many tick-borne illnesses, including:  

• Lyme disease • Ehrlichiosis • Anaplasmosis • Rocky Mountain Spotted Fever • Babesiosis • Bartonellosis 

Note that a tick bite in and of itself does not automatically transmit and cause disease. The longer a dog (or human) has a tick attached to their skin, the more likely disease transmission is to occur. As a general rule, it is not necessary to take a healthy pet to the vet following a tick bite, nor is routine testing of the tick for the presence of pathogens. Tick-borne illnesses have variable incubation periods, and symptoms may take months to develop following a tick bite. 

Seek veterinary care for dogs who are covered in a large number of ticks or who show signs of illness like the following, even if there is no known history of tick exposure:

• Lethargy • Appetite loss • Weakness • Paralysis • Difficulty breathing

Testing and Diagnosis

It is usually not necessary to have a tick removed by a vet, but the parasite must be removed promptly upon discovery. To remove a tick from a dog’s skin, follow these steps:

• Grasp the tick with the tweezers right next to the skin and lift steadily straight up with even pressure.  

• Wait for a couple of seconds - ticks usually let go under tension. If not, continue to pull up gently until the tick releases.

• Clean the wound, hands, and tweezers with regular soap and water.

• Avoid crushing the tick during and after removal to reduce the possibility of disease transmission.

There are tick removal devices available to purchase, but a set of fine tipped tweezers are most effective.

When removing a tick, do not try remedies like nail polish, petroleum jelly, hot matches, or alcohol. Simply remove the tick as described - the goal is to get the tick off the dog as quickly and effectively as possible. 

Veterinary care for a dog a large number ticks relative to the size of the body includes:

• Removing any remaining individual ticks

• Treating the dog with a fast-acting acaricide (tick-killing pesticide)

• Recommending ongoing use of a tick control product to minimize tick bites moving forward

Steps to Recovery

A tick infestation will last until the tick(s) are removed or drop off from the host after feeding. Irritation from tick bites can take up to two weeks to heal, even in the absence of complications like infection. 

If a tick-borne disease is transmitted to the host, the prognosis is dependent on the specificity of the condition and how soon treatment begins.

Prevention

Tick bites are best prevented by regular use of a veterinary-approved tick control product along with regularly screening the dog’s skin and coat after exposure to tick habitats, especially during regional peak tick activity. A large scale infestation and the disease transmission are prevented by adhering to a vet approved external parasite control regimen. Always inform a vet if other animals or children are present in the household when discussing parasite control. 

Environmental controls may also help reduce a dog’s exposure to ticks. Most ticks live in specific habitats like tall grasses, the edges of wooded areas, and overgrown weeds frequented by wildlife.  To minimize a dog’s exposure to ticks, reduce habitat for deer and other animals that regularly carry ticks. Consider implementing the following:

• Increase sunlight to the yard by trimming trees

• Mow the grass regularly, keep bushes cut short, and clear leaf litter and organic debris from under bushes and in flower beds

• Spread cedar chips where the dog lies regularly

Additional tips to minimize a dog’s exposure to ticks at home include: 

• Discourage ticks from migrating onto the property using a wide barrier (3 ft) of gravel or wood chips 

• Buy nematodes (small worms that eat insect larvae) from the local garden center and sprinkle in the lawn and other areas

• Plant species that repel deer

• Regularly spray a vet-recommended insecticide in places where the dog spends time, like dog houses, gardens, flower beds, and shady places like under porches and decks

• Keep the dog out of places wild animals with ticks might go such as crawl spaces, cool hidden corners, and garbage storage areas

• Discourage resident wildlife by installing bright lights, playing loud music, putting up barriers, and leaving cider vinegar soaked rags around until they move on

Is Tick Infestation Common in Dogs?

Exposure to ticks is globally very common in dogs. The probability of a dog receiving a tick bite - and potential transmission of disease - decreases with vigilant screening and maintenance of external parasite control.

Typical Treatment

• Removal of living ticks from dog - Cleaning of tick bite wound site - External parasite control - Environmental controls