Heartworm, Flea & Tick Season

In 2012 we decided to introduce some significant changes to the way we manage the prevention of Heartworm, Fleas and Ticks. In talking with various experts and listening to the community we decided to tackle some growing concerns and develop a new protocol that we believe provides the best protection for our patients and the best value for money for our clients. 

The questions we thought needed to be addressed were:

~ Is heartworm testing and prevention even necessary in this area?
~ Why do we start prevention in June? Isn't this too late?
~ We are seeing more and more ticks, is this a concern?
 Prior to the introduction of newer heartworm preventative medictions, assuring a dog was heartworm negative before beginning treatment was imperative, the older medications could be fatal if given to an infected dog. This is no longer true. The medications we prescribe for heartworm prevention are perfectly safe in infected dogs. However, we have continued to recommend yearly testing mainly because these medications are preventatives and not treatments; surveillance of the efficacy of our prevention program is necessary and the manufacturers of the various preventative products still recommend yearly testing before the veterinarian prescribes the medication.

 Although heartworm remains relatively rare in Ontario, it is important to note that the vast majority of these cases were reported in southern Ontario. Heartworm prevention is very safe and effective, while the treatment for the diseases itself is quite complicated and can have a number of very serious effects. We often advise clients to consider the heartworm prevention provided by the broad-spectrum anti-parasite products we recommend to be a bonus, think of it as flea and tick prevention with the added benefit of also preventing heartworm.

As most dog owners know, spring marks the beginning of “heartworm and flea season”. These 2 parasites are typically grouped together for a couple of reasons; firstly, for the most part they both present a threat only in the warmer months and secondly, the preventative medications we use most often are effective against both.

However, over the past few years, and this coming summer is going to be no exception, we have noticed that the season in which we are seeing fleas is much longer than the typical 6 months we are treating for. Also, the threat of ticks is most definitely increasing. Last year we saw more cases of tick infestation in dogs than ever before. This summer is expected to be even worse as the current tick population is spreading. Ticks do not favour the hotter months and have peak activity from April to June and again in the fall. We now consider ticks to be a growing problem that needs to be addressed. Fortunately tick prevention is also included in some of the flea and heartworm products we commonly prescribe.

Because of this extended flea season and the early bloom in the tick population we now recommend starting preventatives in April or May and continuing for 8 months into the late fall /early winter.