Animal Health
TICK-BORNE DISEASES: A DANGER TO HUMANS AND DOGS typography
vector cartoon illustration of a man and a dog running away, panicked and scared as an oversized tick chases them in an open grassy space

By Christie Capacchione

Red uppercase letter C dropcap with a white outer drop shadow effectreepy, crawly, blood-sucking insects, ticks are real-life vampires. These vectors, or carriers of organisms which cause illness and disease, are a threat to humans, dogs, and other species both domestic and wild. If the host is fed on for a period of time that allows a tick to become engorged, it will regurgitate into the host, spreading any diseases it may carry, with Lyme being the most common.

Signs of illness from a tick bite can manifest in a plethora of ways, sometimes mimicking other illnesses and confusing medical professionals. Therefore, it is important to be vigilant of any tick bites humans or dogs may receive, and to know the symptoms of illness to monitor for and seek medical treatment should they arise.

The Origin of Lyme Disease

There are numerous diseases possible for humans and dogs to contract as a result of a tick bite. However, Lyme disease is currently the most common vector-borne disease in North America. Since its discovery in Lyme, Connecticut during the mid-70s, reported cases of the disease have more than tripled since 1995. It is estimated that Lyme disease is diagnosed in 300,000 people annually, and that number skyrockets to over one million in dogs.

Despite its fairly recent recognition as a cause of disease, Borrelia burgdorferi, the bacterium which causes Lyme infections, has likely resided in North America far longer than any human inhabitants of the country. A research team that was led under the Yale School of Public Health determined there is a high probability of the Borrelia burgdorferi bacterium being at least 60,000 years old, and that it likely originated in northeast North America.

Outer light pink rectangular shaped digital vector illustration three stage infographic detail box that shows HOW DISEASE IS SPREAD regarding a tick animal finding and infecting a host whether it be a dog, human, or both
The Current Epidemic
While first recognized as the cause of illness/disease in the mid-70s, the current Lyme epidemic is not a result of recent introduction of the bacterium to the populations. Instead, it stems from ecological changes responsible for pushing deer, ticks and, finally, the bacterium into more populated areas, allowing rapid spread.

Over the past one-hundred years, deforestation has forced deer into more suburban areas with less threat from predators and stricter hunting laws. These factors have made it possible for their population to rapidly increase. Deer are common hosts for deer ticks, and as their numbers increased in these suburban areas, so did the deer ticks. Hosts such as White-footed mice and Robins are plentiful in these areas as well and further contribute to the spread of the bacterium. Additionally, warmer winters accelerate ticks’ lifecycles and allow them to survive an estimated 28 miles further north each year.

How Disease is Spread
Tick-borne diseases are spread when a tick carrying a disease finds a host and attaches to it with its mouth. The tick then begins ingesting the host’s blood. The organism or bacterium responsible for the disease is in the hindgut of the tick, and as the tick ingests the host’s blood it becomes contaminated with the bacterium. If the tick feeds on the host for 24 hours, it becomes engorged, and as a result, regurgitates. The contaminated blood is now deposited into the host and the host is now infected, as well as a reservoir to infect other ticks if bitten.
Vertical orientated outer light pink rectangular shaped digital vector illustration two stage infographic detail box that shows SIGNS & SYMPTOMS OF LYME DISEASE regarding humans and dogs from a tick animal infecting them
Signs and Symptoms of Infection
If you suspect you or a dog have been exposed, it’s important to know the signs of illness to be aware of. While both dogs and humans can become infected with many of the same diseases, the signs and symptoms can differ between species.

In humans, one of the tell-tale signs of Lyme disease is the appearance of a rash that resembles a bull’s eye. The rash often appears within several days up to one month after being bitten. It is normally found at the sight of the tick bite, but can appear anywhere on the body. While it is not typically itchy, it may grow in size and remain for days or weeks. Other signs include symptoms that resemble the flu, lack of energy and joint pain.

Dogs that have contracted Lyme disease may not become ill or even show symptoms that they have been infected. Despite this, when tested, they can still have a positive result. Unlike humans, dogs will not get a rash. Instead, symptoms of infection may manifest through loss of appetite, lethargy or limb lameness, which swaps between legs.

Diagnoses
Humans suspecting they have become infected should contact their medical provider. Diagnosis typically involves discussing symptoms and knowledge of any previous tick bites, level of exposure and a blood test. They may even want to know if any dogs in the home have been diagnosed. If so, it is more likely for human residents to become infected as well. If the person found a tick attached to them, they can remove it and send the tick for testing to determine if it is a carrier of disease.
If a dog is suspected to have contracted a tick-borne illness, they will need an appointment with their veterinarian. Similar to a human doctor visit, the veterinarian will want to know if any ticks have been found attached to the dog, discuss any symptoms noticed and determine the level of exposure likely. Oftentimes a blood test that will check for several different tick-borne diseases can be performed in the office with results available in just a few minutes.
Treatment
If a patient—human or canine—tests positive or has enough symptoms that warrant treatment, a course of antibiotics is prescribed. Doxycycline taken orally is the most common antibiotic used to treat Lyme disease in both dogs and humans. However, in severe cases, it may also be administered intravenously.

The duration of treatment using oral medication usually lasts for several weeks. It is important for humans to limit their exposure to the sun while on this medication. Additional treatments available to both dogs and humans to help ease joint and muscle pain can include massage, acupuncture, MagnaWave therapy and red light therapy.

Prevention
Taking precautions to avoid yourself or a dog being bitten by a tick can help lower the risk of infection. Know the times of year ticks are most active in your area and avoid activities in areas with tall grass, overgrown brush or low-hanging branches whenever possible. Use bug spray and wear light-colored clothing to make ticks easier to spot. Check yourself and dogs for ticks immediately after outdoor activities. If any are found, remove and dispose of them.

Monthly preventatives are available for dogs in topical and oral forms. Dog owners should discuss with their veterinarian which preventative is right for their individual dog. Additionally, there is a now Lyme vaccine available for dogs.

Tick-borne illnesses are unarguably on the rise with the number of cases diagnosed in humans and dogs climbing annually. This threat is not likely going away anytime soon due to environmental changes allowing ticks to expand in areas ripe with hosts, which have allowed disease-causing bacterium to spread. Understanding the risk of exposure in your area, along with practicing prevention methods and being vigilant for signs of infection, will keep both you and the dogs you care for enjoying the outdoors in all seasons.

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Vector cartoon digital illustration of a tick animal progressing forward in motion
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