Sudden hairloss

I’ve just discovered a patch under my 11months old cat neck.  And I can’t seem to figure out what’s caused it. He was in a different environment from 9th-13th April, as I was away and during this time he was a little stressed and was hiding behind the washing machine alot . As he had ring worm when he’s around 3months I am scared he has gotten it again. In aware it could be a number of things causing this but as  I can’t get him to the vet until next week Thursday.  I thought to ask here    

Hello - I'm afraid that Ringworm is certainly a possibility. Ringworm can be caught easily by small kittens whose immune system is still immature, but 11 months is quite old for this to happen and I wonder whether illness or severe stress may be behind it. Cats do not help us in this regard; they are not so social that they communicate illness or stress to one another or their owners very readily.  As much as we owners would like to think that we'd know if something was worrying our much-loved cat, it can be very well hidden at times.  Thus Ringworm (or Demodex, a non-itchy mite with similar implications) can be the first sign of a hidden, underlying problem such as viral disease, chronic pain, bladder disease or even cancers.  Other possibilities include rubbing or scratching due to dental pain; skin erosions secondary to kidney disease; infections or mites; even, on very rare occasions, illness as sinister as lymphoma.  More common things are obviously much more likely than this last but it sounds to be a good idea to get an examination and tests in to action as necessary.  Please do take your boy to the vets.

Meanwhile, it's worth mentioning a few everyday things that you may not have been expecting that could be contributing to stress in a household.  Typical examples include relations with other cats or other pets, visitors, a change in furniture, a new cat in the neighbourhood, and so on.