Fungal? Allergies?

Christmas of 2021 we went to Gatlinburg TN and after coming back home she started getting these spots, I have another yorkie but he doesn’t have any of these problems so I know it’s not spreading upon contact. These spots are crusty, red, itchy, just awful looking. She gets half a Benadryl twice a day, sprayed with VetOne GeOne twice a day (even tried the Veterinarian Formula brand from Walmart), and washed with Veternarian Formula brand anti-fungal pet wash once, sometimes twice a week, since Christmas. Every day it’s the same process. The only difference is it takes away the redness and itchiness. I am at a loss really, my local vet has given her two steroid shots in the last 6 months. He just states it’s allergies, but since December/January? Would it last this long and NEVER go away? These spots are along her spine, chest/upper belly area, under neck, side of neck, around her butt area, and her hind legs. Her paws aren’t red, the only thing that is red is around these spots. Thank you, I appreciate any kind of insite of what this may be.

Hello!  I'm afraid that you can't rule out itchy parasites purely on the fact that one dog has it and an in-contact dog doesn't.  This is because some parasites cause reactions, or even allergies in one animal but not another, even when they are only present in the environment in extremely low numbers (much as some people literally get a reaction from the dust of a peanut).  Dogs have been known to have ringworm (non itchy) when a healthy in contact dog doesn't and the same is true for reacting to fleas or mites in the environment (mites can take hold in an immuno deficient body much more easily than in a dog with a more competent immune system).

Assuming that your vet has correctly diagnosed allergies then yes, there may be things in your environment that a dog is allergic to that may be present all year round.  Dust mites are a common one.  There are also plenty of dogs with more than one allergy - and it is common for the number of allergies to increase in itchy dogs with age.  A secondary effect of allergies is a tendency towards bacterial and yeast infection in the superficial skin (dog scratches skin, micro-beastie moves in) so microbeastie control sometimes needs addressing.   Allergies are chronic diseases - once dogs have them, they have them - but still shouldn't be dismissed as 'normal' for that dog because as you sound to be very aware, they can be bothersome and sore.  Just like a dog with diabetes, skin patients should be reassessed regularly as they can be ever-changing and very compromising to live with.  Sometimes, clients want to explore options or address issues with their dogs' skin beyond the scope of their vets' knowledge.  If you feel this to be the case then perhaps there is a dermatologist locally that they could refer you to? I hope that something here is of help.

The lesions that you are showing may be epidermal collarettes which can be connected to superficial bacterial infection.  If your vet feels this to be the case, they will sometimes prescribe an antibacterial / antibiotic wash.  However, epidermal collarettes are simply a feature of allergy.