Where are Flea and Tick Populations the Worst?

Areas with Prevalence of Fleas and Ticks

By Jennifer Kvamme, DVM

Fleas and ticks pose more of a problem for dogs and cats in certain parts of the United States than in others. A climate where the environment is warmer and more humid allows populations of fleas and ticks to explode, causing serious health concerns for the cats, dogs, and humans in these locations.

The distribution of certain tick and flea species varies depending on an area's climate. Climates that experience colder winter seasons get some respite from dealing with ticks and fleas for a few months during the year, while hot, dry climates are less hospitable for fleas and ticks year round.

Tick Populations

In recent years, ticks that were more commonly found in the southern part of the country have started to expand their populations into northern areas. Ticks of the Ixodes and Amblyomma species are making their way to climates that were previously too cold for them. With warming temperatures, wildlife conservation programs, reforestation, and expansion of urban areas, tick migration is on the rise.

For example, the deer tick (Ixodes scapularis) is finding its way to new locations with the help of a growing deer population in the eastern part of the United States. Along with the increasing population of deer ticks comes the increased likelihood of Lyme disease and/or anaplasmosis transmission to dogs and cats in that part of the country.

Because migrating tick populations bring with them potential diseases that have not been a problem in certain areas before, it's becoming increasingly more important to protect your pet from ticks. Using tick prevention medications, vaccinations, and having your pets screened for various tick-borne diseases is essential. Your veterinarian can provide the best advice as to which diseases are more prevalent in your area.

Flea Populations

The most common flea species affecting cats and dogs in the U.S. is Ctenocephalides felis, or the cat flea. While fleas may be found anywhere in the country, they are found in greater numbers in areas where higher humidity levels and warmer temperatures exist.

This is why you will see a major flea problem in Florida even in the winter, while in Chicago they become less active for a few months of the year. In the drier desert regions of the U.S., humidity levels are typically not high enough to support the flea life cycle. Because of this, your pets are at lower risk of developing a flea infestation in those states.

Even if you live in an area of the U.S. that may not be known for having large numbers of fleas and ticks, your pet may still benefit from preventive medications. Your veterinarian can give you the best advice as to your pet's risk for flea infestation or tick-borne diseases. Prevention is always easier, safer, and less expensive than treating a disease once it's become established in your pet.