Cheyletiella mites

our indoor rabbit Gus had his myxi injection 3 weeks ago and a couple of days before his VHD we noticed the fur around the back of his neck (near the injection site) had fallen/been bitten out, we assumed it down to him scratching the small scab from his myxi jab, but when we took him to the vets today, he reckoned it was mites and applied a small amount of 'spot on' and said that would clear it straight up.

However having read up on that type of mite, I read they often carry myxi and can be very difficult to get rid of. We have hoovered up all his old hay and forage. When I spoke to the vet he said the mites could only be passed on through rabbit to rabbit contact, (which I told him was impossible as myself, my OH and Gus have never done this. I was worried it could have been from the forage of bramble and hawthorn I have collected and given to him, but the vet said it wouldn't be that.

Has anyone' rabbits ever had these mites and if so, what was the/how extensive was the treatment ??

Bit worried now as the fur further down his back has also receded a bit tonight, he was in his little hidey hole for a couple of hours and is scratching/biting himself more than usual when he is grooming himself

any advice much appretiated

To be honest it does sound like a reaction to the injection rather than mites. There is a known reaction to one type of VHD vaccination called Cylap I think (best look for original thread on here) My bunny pebbles had a similar reaction to an injection he had when he had an op to remove a tumor and it did look very much like mange to start with, but was only isolated to one area and once the large scab fell off, his fur grew back and we had no re-occurance.