Recording went a little smoother this week! I think we were much less nervous, and there was much less baby chatter in the background.
Anyone who has fostered or rescued kittens should be familiar with what I’m about to describe: sneezing, nasal discharge, eye discharge, crusty noses, wheezing, and goopy eyes that might even glue themselves shut. Upper respiratory disease is one of the most common reasons cats present to the general practitioner, especially during kitten season when abandoned kittens are a dime a dozen, and rescues reach saturation. Multiple cat households and animal shelters are the environments where upper respiratory disease have the highest prevalence – if I had to guess prevalence is most likely 85%.
There are two states that this disease exists in, and I think it’s important to understand what both those disease states are so that you understand why your adult cat may have occasional remissions of sneezing and eye goop. Your classic origin story of feline herpesvirus begins with a kitten that was dropped off on someone’s porch and they are being awesome nurturing saviors, nursing it back to health, but noticed that she is maybe underweight, sneezy, has her eyes glued shut in the morning, or maybe even has signs of pneumonia or a bad appetite. This is the acute phase of herpesvirus. Generally these infections clear after about 2-3 weeks of both systemic (oral) and ophthalmic (eye) antibiotics.
The second state, which is what many owners of adult cats may find familiar, is the chronic state. These are what we call latent infections – meaning that they are carrying the virus but not experiencing illness… until a stressor occurs such as moving houses, a new pet, or boarding while owners are on vacation. A seemingly healthy adult cat will then suddenly experience signs like sneezing, nasal discharge, or eye discharge. Usually these episodes are fleeting and either self resolve or resolve with antibiotics. This chronic carrier state is the reason we thought this was an important topic, because in almost all of these appointments, I tell the owner that their cat is having a flare-up of an upper respiratory disease and that they most likely have been carrying a virus since kittenhood. When they ask me which virus it is, and I tell them herpes, they always looked mildly shocked. So I just wanted to demystify herpes a little bit and maybe reassure the cat owning population that their cats aren’t up to anything naughty.
Now, a couple points to drive home. One thing I want to discuss is that although chronic, adult carriers usually only have occasional and mild flare ups, some adults may experience much more serious sequela (consequences) of chronic herpesvirus. One of these things are serious ocular/ophthalmological conditions like recurrent corneal ulceration, vestibular syndrome which you may recognize if we called it vertigo, and something called erosive sinusitis where the virus can actually eat away at the nasal turbinates. These are extreme cases, but they do exist.
The other thing we should discuss is that herpesvirus tends to coexist with other upper respiratory viruses, and we refer to that as a virus complex. Usually herpesvirus likes to be with a buddy, like calicivirus, feline leukemia, and FIV. Generally your vet can determine if herpesvirus is acting along with another virus by some subtleties in the combination of symptoms. For example, if the cat in question also has some gingivitis, ulceration on their gums, or other oral symptoms, I tend to assume calicivirus and herpesvirus are acting in tandem. Calicivirus isn’t necessarily a big deal, but you will want to know if your cat has leukemia or FIV, so it’s a good idea to let your vet perform a simple in-house test called a SNAP test that needs two drops of blood and ten minutes.
So you’ve heard me mention antibiotics and you mind be wondering why we would use antibiotics to treat a viral infection because in human medicine that’s a hot topic. Just like herpesvirus likes to have a virus buddy, it’s also a big enabler for concomitant bacterial infections. A viral infection creates a really welcoming environment for a bacterial infection to move in, so any time that you have a rescrudescence, or a flare up, of an upper respiratory virus in a cat, you’ll also have a bacterial infection that tags along, and even though the virus will blossom and fade, the bacterial infection has the staying power to cause the more dangerous sequela like pneumonia or sepsis.
There are a couple adjunct therapies we have in our medical toolboxes to manage the more milder flare up cases that don’t require antibiotics. Adjunct therapies are treatments that can be performed in conjunction with medications to reach an even more favorable result, and usually they are non prescription or nursing care related. Nowadays, “adjunct therapy” has been rebranded as “natural” or “holistic,” with many people who advocate against western medicine claiming that we vets don’t know about these therapies. Classically, we have always understood these methods, it’s just sometimes we think they should be done in conjunction with medication. But i digress.
Adjunctive therapies for herpes infections, either chronic or acute, are L-Lysine and steam therapy. L-Lysine is an over-the-counter supplement that can be used either daily or from time to time for the duration of a flare up. L-Lysine is an amino acid, which means a tiny piece of a protein, and it blocks a different amino acid called arginine. Arginine is what herpesvirus needs to replicate and spread itself around the body. Recently the efficacy of L-Lysine has been debated, but I’m in the “yes it works” camp. It comes in a tasty paste that they actually really love.
Steam therapy is something that makes people look at me like I have nine heads. Some cats either really love this or won’t tolerate it at all, but you would be surprised so I say try it and see what happens. A lot of people come back to me and told me that their cat loved it. So this is what you do – when there’s a flare up, once or twice a day you call the cat into the bathroom with you, close the door, and run a hot shower. You don’t HAVE to shower, but you do whatever you wanna do, I’m not here to judge. Leave the cat in the bathroom for ten minutes (or more if she’s into it) while the room gets nice and steamy. That’s it. Then letter out.
Stay tuned for the podcast episode release where we chatted a little bit more about why some vets find it easy to talk about herpes and others prefer not to. We also discussed the behavior of Herpesvirus itself, where it likes to hide out and lie dormant, and why you can’t get herpes from your cat.