Listen as Dr. Mindy Cohan talks with Kathy about the dangers of fleas, ticks and heart worm and how we can help prevent our dogs/cats from becoming their next meal!
Fleas, Ticks and Heartworm
The arrival of spring brings many beautiful flowers and blossoms on the trees. Unfortunately, the warm weather also beckons the emergence of fleas, ticks and mosquitoes. These insects pose health risks to people as well as dogs and cats.
Fleas suck blood from pets and can cause anemia, a decrease in the body’s red blood cell count. For small, young animals, a heavy flea burden can cause severe anemia and possibly death. When a flea takes a blood meal, flea saliva is transferred into the host’s body. It is the flea saliva that causes an allergic response and severe itchiness experienced by some dogs and cats. Fleas can also transmit tapeworms to dogs and cats and cause feline infectious anemia.
Ticks also carry several infectious diseases that pose a threat to pets. Lyme disease is the most common illness transmitted by ticks. Dogs are most commonly affected by Borrelia burgdorferi, the bacterial agent that causes Lyme disease, but cats, cattle and horses can also be affected. People can become very ill from Lyme disease.
Lyme disease is very common in our area and the northeastern United States. It is also found in Wisconsin, Minnesota and parts of California. Animals such as the white footed mouse and white tailed deer carry Borrelia burgdorferi, but do not become ill. When a tick feeds on these wildlife, it picks up the bacteria. The tick then bites a dog or person and transmits the bacteria. The tick must be attached for at least 24 hours in order to pass the bacteria. Dogs cannot pass Lyme disease to people or other dogs; only ticks can transmit the disease.
Once a dog is bitten by a tick carrying Borrelia burgdorferi, it becomes “Lyme positive.” This does not mean it has Lyme disease, just that there has been exposure indicated by a blood test. From the time a dog is exposed to the Lyme agent, it can take several months before any symptoms are seen. The typical clinical signs of Lyme disease in dogs include:
- Swollen joints
- Decreased appetite
The good news is that most dogs exposed to Borrelia burgdorferi do not develop Lyme disease. It is also favorable that dogs symptomatic for Lyme disease recover very quickly once antibiotics are started. There is a small percentage of dogs, however, that have persistent joint problems or suffer kidney damage related to Lyme disease.
Besides Lyme disease, ticks can also cause diseases such as Anaplasmosis, Ehrlichiosis, and Rocky Mountain Spotted Fever. These diseases cause similar symptoms to Lyme and are also treated with antibiotics.
According to the Companion Animal Parasite Council, the incidence of tick borne disease in dogs is rising. The incidence of heart worm disease in the U.S. is also increasing with a 166% increase in reported positive cases in the past 3 years. Heart worm disease is transmitted by a different vector, the mosquito. It can affect both dogs and cats, but it is seen more commonly in dogs. Heartworms have also been identified in ferrets, wolves, coyotes, foxes, sea lions, and rarely in people.
When a mosquito takes a blood meal from a dog, the immature form of the worm enters the dog’s skin. Over about 6 months, the worm matures and will then mate and produce more worms. The adult worms live in the heart and nearby blood vessels. As the number of worms increases, the damage to the heart and lungs becomes worse. The common symptoms are coughing, decreased ability or willingness to exercise, decreased appetite and resulting weight loss. As the disease progresses, dogs will experience heart failure and another life threatening problem called caval syndrome. Caval syndrome requires immediate medical attention and is treated by literally removing the worms from within the patient’s heart. This is a dangerous procedure with many risks.
Cats do not develop as many worms as dogs, but just a few heartworms in a cat can cause significant health problems. Cats will show similar symptoms such as coughing, poor appetite, weight loss and sometimes vomiting. Cats can also show signs of heart failure such as difficulty breathing and fluid in the abdomen.
Heartworm disease is diagnosed with a blood test. There is a treatment available for dogs, but this harsh medication is not safe to use in heartworm positive cats. Because there is no treatment for cats and the treatment for dogs can have serious side effects, prevention of heartworm disease is best. Heartworm can be prevented by giving your pet a medication on a monthly basis. Year round prevention is recommended, even in cold climate areas. Many heartworm preventatives also help to prevent intestinal parasites, so there are multiple benefits.
For more information on heartworm disease and a cool video, visit
For more information on Lyme disease and a great podcast, visit