It only takes one. One mosquito bite to infect your pet with worms that grow inside their heart and lungs. One flea bite to inflict suffering with an allergic reaction. One tick bite that could result in a deadly tick-borne disease. Veterinarians across the United States stand in unison about the most effective treatment against parasites—year-round prevention. 

External and internal parasites and the diseases they transmit have increased in prevalence in the United States over the last two decades, according to a 2021 study. For example, most samplings showed that one in five, or at best, 1 in 20 dogs test positive for intestinal parasites. Similarly, ticks can be found in all 50 states, with each one carrying more than one disease-causing agent. Fleas simply lurk about, waiting to sense body heat and then jump, bite, and lay eggs on the host. At Emerald Animal Hospital, we recommend year-round parasite prevention for many reasons.

Pet parasites lurk inside and out, regardless of cold weather

Warmer temperatures are ideal for parasites to breed, but that does not mean they disappear in colder climates—they simply lie dormant and never really go away, so year-round parasite prevention is essential. 

  • Fleas — Fleas die in freezing temperatures, but chances are you do not keep your home below 70 degrees—which keeps their eggs warm. One of the most common reasons pet owners take their pets to the veterinarian is because of flea allergy dermatitis, an intensely itchy immune response to fleas that spurs hair loss and infections that will not go away until treated.
  • Ticks — With ticks, snow is known to act as an insulator, and some ticks remain active underneath, so long as the temperature is above freezing. Ticks transmit Rocky Mountain spotted fever, a zoonotic disease (i.e., one that can be transmitted between pets and people) with signs that include fever, joint pain, blood clotting problems, and neurological issues. Ticks also transmit ehrlichiosis, which has similar signs, but also is often characterized by nose bleeds, bruising, or anemia.
  • Mosquitoes — Mosquito eggs also are not so affected by cold weather. These pests hide in warm, moist crevices in and around your home, and lay their eggs, which can survive cold weather. Even mosquito eggs that have dried out can still hatch up to eight months later. Unpredictable weather, particularly an early spring or wet fall helps mosquitoes, which can transmit heartworm disease to pets. In dogs, heartworms can cause heart and lung disease with coughing and fatigue, but treatment is extremely difficult and dangerous. For cats, no treatment is available to eliminate heartworms. 

Pet parasites hide on your pet

Parasites seldom are visible to the naked eye and not all pets show obvious infection signs. Also, despite the misconception about indoor animals, 30 percent of indoor cats are diagnosed with intestinal parasites. Because both fleas and ticks are hard to see, owners may not be aware of the parasites. Fleas in particular multiply at alarming rates—another reason for parasite prevention.

  • Fleas — In your home, 50 percent of the flea population is made up of eggs, with only 5 percent of the population made up adults that live on their host. The actual fleas are hard to see, but you may see lesions and bare skin on pets who are flea allergic and constantly scratching, or flea dirt on your cat’s bedding. As few as 20 fleas indicate an infestation, and two fleas can quickly become hundreds. Fleas can also carry Mycoplasma haemofelis, which can lead to anemia and weakness, and possible death, especially in puppies and kittens. Bartonella infections, which also are linked to fleas, lack apparent signs.
  • Ticks — Ticks also are microscopic in their larvae stage, and only the size of a poppy seed as nymphs. In addition to Lyme disease, ticks can also transmit Borrelia bacteria, which cause signs including lameness, limping, and lethargy, and Anaplasma, which can be transmitted by the black-legged tick and causes bleeding disorders. 
  • Mosquitoes — Mosquitoes, which are less than 0.1 inches long, are everywhere, as anyone knows. In heartworm disease’s early stages, pets may not exhibit any signs. By the time they do, the heartworm load is likely heavy, and sadly, if your pet reaches a later stage of heartworm disease, they can experience heart failure or cardiovascular collapse. Cats who have heartworms can collapse and suddenly die. 

Pet parasites survive in water

Water is a breeding ground for many parasites, particularly mosquitoes. Parasites can survive in water where eradicating them is impossible—yet another reason for protecting your pet, who likely goes near water bodies. 

  • Fleas — Fleas may not wash to death in your washing machine, despite popular belief. Both dogs and humans are susceptible to the flea-carrying disease, typhus, which can be deadly. 
  • Ticks — Ticks and lice, which are both resistant to water, also can carry disease. Ticks do not swim, but they can survive submerged under water for extended periods of time. 
  • Mosquitoes — Many mosquitoes lay their eggs in standing water (e.g., uncovered trash, pool covers, kayaks, wheelbarrows, outside toys). If you have any standing rain water in your yard, you may also have a mosquito motel. 

Pet parasites live in your yard

How do you protect your pet from feces-contaminated soil without parasite prevention? Intestinal parasites, such as roundworms and whipworms, can survive for several years in the ground, because of feces in the soil—reason alone not to allow kids to play barefoot, given the zoonotic disease risks. If your unprotected pet spends time outside, they run the risk of being bitten. 

  • Fleas— Your yard is a wonderful breeding ground for fleas. Plus, if your yard is cluttered, wildlife such as flea-carrying rodents or squirrels no doubt appreciate the discreet hiding places. If your dog swallows a flea when they groom, they may get tapeworms that will attach to their intestinal lining and lead to serious nausea and diarrhea.
  • Ticks — If you love a nature walk, or simply walk near trees and brush, ensure you check yourself and your pet for ticks afterward. But, don’t assume ticks are only in tall brush in wooded parks, because black-legged ticks are known to hide in piled leaves in the winter.  
  • Mosquitoes — If you have unretrieved feces lying around your property, mosquitoes are sure to find it and use it as a breeding ground. 

Protecting pets from parasites

Since little—not even the weather—destroys the parasites that can infect your pet, clearly your pet requires year-round parasite prevention that protects them against diseases caused by fleas, ticks, and mosquitos. Pets also need protection from roundworms, hookworms, and whipworms, which can be included in their prevention plan. 

To learn more, the Companion Animal Parasite Council, an independent non-profit, provides current guidelines for pet owners and veterinarians, and offers parasite forecast maps that provide monthly monitoring of every U.S. county.  

Contact us at Emerald Animal Hospital to schedule your pet’s next wellness visit, where we will recommend a customized parasite prevention protocol for your pet. We will help you to understand your options and explain more about the importance of parasite prevention for your pet’s health and comfort.