By Kate O’Hara, BVetMed
General Medicine, Angell Animal Medical Center
Fleas and ticks feed on the blood of their hosts which can include wild animals, people, and our pets. In addition to being a nuisance, these ectoparasites can represent a significant health risk to our cats and dogs directly by causing Flea Allergic Dermatitis (a skin condition resulting if the pet has an underlying allergy to the flea bites) or anemia (a low blood level) if there is a heavy burden. Fleas are also responsible for transmission of diseases such as Feline Infectious Anemia, Cat Scratch Fever (bartonellosis), and tapeworms. Ticks can transmit Lyme Disease, Babeiosis, and rickettsial diseases including Anaplasmosis, Ehirlichiosis, and Rocky Mountain Spotted Fever. Certainly we owe it to our pets to protect them from these dangers. The good news is that we do have easy and effective ways of preventing fleas and ticks on our pets and keeping these parasites out of our homes.
Understanding the life cycle of the parasites is important in forming an effective plan for prevention. Most ticks have 4 life stages: the egg, larvae, nymphs, and adults. Between each stage, the tick will require a blood meal, and then will drop off the host into the environment and molt.Ticks can feed on mammals, birds, reptiles, and amphibians. Most ticks prefer to have a different host animal at each stage of their life. Therefore most ticks will be found in the outdoor environment. Ticks will become inactive during the cold winter months, but are active throughout the Spring, Summer, and Fall.
There are also 4 stages to the flea life cycle: the egg, larvae, pupae, and the adult flea. The egg is laid on the host and falls off into the environment to hatch. The larvae and the pupae which then develop are also found in the environment. Only the adult flea, once it emerges, lives on the host and reproduces. The average time it takes for a flea to develop into an adult is 3 weeks, though this time frame can be faster or slower depending on the environmental climate/ conditions. If fleas become established indoors where it is warm, they can thrive and continue to reproduce throughout the year.
Many times people are unaware of the dangers of these parasites, or do not believe that their pets are at risk. Clients often tell me: “My pet doesn’t have a problem with fleas or ticks.” What they are not aware of is that in most cases, people will not actually see fleas or their effects until there is a heavy burden or unless the animal has an allergic reaction to the bites. Most parasites do not actually want to make their hosts sick. Doing so would mean loss of their food source. Also, as their life cycles illustrate, the majority of the parasite population is found in the environment and not on the animal. Cats, in particular, are very good at grooming adult fleas and ticks off of themselves and removing “evidence” that there is a problem. I have seen many dogs test positive for tick-borne diseases when their owners have not witnessed ticks on the dogs, so we know they are out there. Our goal in dealing with these parasites is prevention. We do not want to wait until parasites become an obvious problem before dealing with them. It is much easier (and cheaper!) to prevent an infestation rather than trying to clear one once it is established or dealing with the diseases parasites transmit.
Targeting the ectoparasites at more than one point in their life cycles is most effective. Routinely treating the outdoor environment during flea and tick season will lower the overall burden in the area and make control easier. Routine topical treatment of pets aims to kill fleas and ticks and prevent the ticks from attaching. Some owners prefer to apply these topical preventatives only during the active flea and tick season. However, we recommend year-round monthly treatments. This is because of the unpredictable timing of the season and also because prevention will be most effective when started during the cooler months when the environmental burden is lower. Trying to fight against a larger population later in the season is more difficult. Owners can also significantly decrease the risk of disease transmission from ticks by performing routine “tick checks” and removing any that are found. Of course, this may be more difficult on pets with long dense coats.
Ask your veterinarian about starting a preventative treatment plan for your pets. We would be more than happy to advise. For information about Angell’s General Medicine service, please visit www.angell.org/generalmedicine or call 617-524-5653.