As I sit at home this holiday weekend, trying with marginal success to fight off this nasty cold/bronchitis/laryngitis, I thought I would address some of the issues my clients express concern about with human and feline "colds".
Firstly, I did NOT catch this bug from any of my patients. Humans cannot catch feline upper respiratory viruses - most of those are due to FELINE herpesvirus, and most of the rest are due to FELINE calicivirus. I almost certainly caught my illness from the sick toddler I sat next to on the flight from LAX to Minneapolis, or perhaps in one of the three airports I was in that day, or even at the very busy shopping mall the next day.
Secondly, I am always a little concerned about spreading this sort of thing to my patients or my own cats because it IS possible for a few of the hundreds of human cold viruses to be spread to cats. This is known as a reverse zoonosis or an (and I like this word better, it's so scientific-sounding) anthroponosis. Fortunately, if a cat should be unlucky enough to catch it from me, it would tend to be fairly mild and self-limiting, and would not be able to spread on to other cats or back into humans - it would come to a dead end in that particular cat.
Thirdly, if this had been influenza instead of a cold (it's far too mild to be flu), I would have some serious concerns about spread to cats, but only if I had failed to get immunized against H1N1 influenza. That is the strain that was in the news so much a couple of years ago - I was vaccinated against it then, and I noted that it is also a component of this years routine annual flu shot. H1N1 has in the past spread to an unfortunate few cats and had a mortality rate of about 50%, so I consider it imperative that I protect myself as a way of protecting my patients and my own pets, along with humans.
Lastly, let's go back to that nasty feline herpesvirus. This is the bug that causes the majority of feline upper respiratory disease AND nontraumatic eye disease. It is probably the most common pathogen in cats, and one we have vaccinated cats against for decades. Being a herpesvirus, cats can only catch it once - then they have it, for life. So one would think that vaccinations at that point would have no value. But it turns out that cats with strong immunity to the virus from annual vaccinations do a better job of fighting the darned thing when they have those seemingly inevitable "recrudescences". Back before the recession, when most of my patients were current on their annual FVRCP-C vaccination, I rarely saw cats with upper respiratory or herpes-related eye problems that warranted any treatment whatsoever. But now that so many cats are overdue on vaccinations and their immunity is waning, medical intervention and good home nursing care are much more necessary.
So I guess the gist of this post is (big surprise here): get your annual flu shot, and get your cat vaccinated annually, too. The alternative is much bigger vet bills, and often a much sicker cat.
Here is my current likely nemesis - a picornavirus (actually, a whole cluster of the little devils - if you look close you can even see their horns and cloven feet):