The Importance of Heartworm, Flea & Tick Prevention

By Sue Jex, CVT

March and April are the months to start thinking about prevention for both dogs and cats.  Heartworm can affect both species and can be life threatening.  The disease can also affect ferrets, wolves, coyotes, foxes and rarely humans.  Dogs should be tested for exposure prior to starting or continuing prevention, but there is not a reliable test for cats.  Heartworm is transmitted by an infected mosquito.  The mosquito takes a meal from an infected dog and then takes a meal from an unprotected dog thus transferring Heartworm larvae.   Even if your dog doesn’t go outside for long periods of time, mosquitoes can still come into your home and possibly infect her/him.   There has been an increase of positive cases because of dogs coming up from southern states (Heartworm is more prevalent there).  One sign of heartworm in a dog is a mild persistent cough, not wanting to exercise, lethargy after moderate activity, not eating as much and weight loss.  For cats, Heartworm infection is harder to detect because cats are much less likely to have adult heartworms since cats are not an ideal host.  Some infections can resolve on their own, but often these infections cause damage to the respiratory system.  If there are Heartworms in the circulatory system, they can affect the cat’s immune system.  Symptoms such as coughing, wheezing and difficulty breathing can be seen.    The preferred method for screening cats is the use of both the antigen and an antibody test (which detects “exposure”).

          Fleas and ticks can be picked up by your dog or cat by being outside or having someone accidently bring them into the house.  Ticks are most common around woody areas and fields, but can be blown by the wind into other environments.  Fleas can be picked up from a wild animal walking through the yard and dropping fleas as they walk and your pet walks in the same area and picks them up.  The Deer tick is the tick that can transmit Lyme disease to dogs (people, too!).  Dogs can be exposed to Lyme disease or carry it and it is important to test for exposure.  Dogs with Lyme disease may show signs of fever, lethargy, lameness (the lameness can shift to different legs).  Once fleas come into the house, it can be difficult to get rid of them.  Any and all pets must be treated with a product to eradicate them.  The house needs to be thoroughly treated either with foggers or similar products.  You would need to be sure all dark areas are completely treated.  Dark areas would include:  under all furniture, beds and along all baseboards.  Vacuuming with a disposable filter after treating the house is recommended.  A professional service can also help you rid of the fleas.  All bedding the pet(s) use would need to be washed.  Fleas can cause Flea Bite Dermatitis which causes your pet(s) to itch.

There are many products that help with the prevention of Heartworm, fleas & ticks.  Frontline, Revolution, Sentinel, Vectra, Effipro & Effitix are topicals (topicals are applied to the skin & the sebaceous glands help spread the product throughout the body) that need to be applied monthly.  Heartgard (for prevention of Heartworm disease) and Nexgard are chewables which are given monthly.  Bravecto is also a chewable that is given every 12 weeks.  Some of these products also help with other parasites (ex. roundworms, hookworms, mosquitoes, lice and ear mites).

Flea & tick collars (Seresto or Scailbor) are generally recommended due to the fact that chewable & topical products are 90-95% effective.  The ingredients of the collars work together with either the chewable or topicals mentioned above. Over-the counter brands (Hartz for an example) are not recommended to be used with other products.  The ingreidents in those collars & using both products can have the potential of over dosing and cause adverse effects for the pet.