Much is written every year regarding the dangers surrounding hot weather and the possibility of heat stroke in dogs and cats. We are all well aware of the risks of leaving a pet in a car during the summer months even if the car is parked in the shade and the windows are left down. But with the extremes of weather in New England this summer, we are witnessing an additional aspect of heat and pet behavior that appears to be considerably more common. Frequently, clients have been describing their pets as “lethargic, disinterested and having less of an appetite. Occasionally loose stools and vomiting is reported as well. Although we can’t ignore these symptoms and apparent changes, laboratory work is often normal and tick and flea disease panels are negative for illness. So what is happening here? Are we being assaulted by an unknown “mutated virus”? Is there a new organism that is affecting dogs and or cats? Are the ticks carrying a new and, as of yet, undiagnosed disease? Probably not. This “epidemic” of abnormal behavior seems to be no more than “high heat index” syndrome.

This is not a real, proven disease but rather a phenomenon we witness to some degree each summer. Given the extremes of this year, our four legged friends don’t seem to overcome these factors, even as well as most of us do. Yes we spend the day going from air conditioned office to air conditioned car to air conditioned house but do we humans feel the same as on a sixty degree day in the fall when we are not living in “conditioned air”? No we don not. Our bodies seem to recognize the difference between naturally cool and dry air as opposed to the artificially produced variety. Although reasons aren’t clear it seems to be adaptive behavior that evolution has created. By reducing our activity, decreasing our appetite and forcing us to take life a bit slower during the very hot and humid weather nature helps us to conserve the energy expended in heat regulation and bodily functions. Our pets may very well be doing the same thing.

So although a high heat index is no reason to ignore gastro intestinal signs, lethargy or lack of appetite in our pets, it may just be normal adaptive behavior. Even if we are all living in a “nice air conditioned environment”.