Do you develop immunity to hand, foot and mouth?>

[Twiglett]

I thought you couldn't catch it again, but DS's best friends' mum says her DS has just got it for the 3rd time.

I am sure she is wrong. When my DD1 caught this and I caught it from her - usually much worse in adults apparently. Our GP said she was mildly surprised I caught it and had never heard of it as it is a common childhood bug that most people catch as a child and so don?t hear of so many adults with it, relatively rare in adults though obviously not impossible (implying immunity). I have always just thought that it is a one off bug. I wonder if he has got an allergy rash from something he has touched and touched his feet? or a food allergy? I would be surprised if a GP has diagnosed it three times - bet they did the first and then she has seen similar symptoms and labelled it as the same thing.
Could be wrong though - no expert just talking from my personal experience with this nasty bug. If you have not had it, stay away as it can be so painful if you get it in the mouth, worse than tonsillitis.

that's what I thought bathmummy

.. she called me last night to say that he has blisters in his mouth(its DS's 4th birthday party today so she was worried he had it too)

I think HF & M is just a name for a collection of viruses rather than one virus IYSWIM. My GP said we could get it again (hope not, I got it and it was really uncomfortable)

kids get blisters in their mouths without it being hand foot mouth. Ulcers/blisters are horrible, my eldest often gets them when she is run down, after a cold for example. If this is the only symptom, I would just treat it as mouth ulcers and give bonjela, antiseptic child friendly mouthwash etc. and keep an eye on it. If there is nothing on hands or feet then extremely unlikely to be anything more sinister.

clayhead, just crossed posts. Interested in your post about being a collection so looked it up.
HFM is also called vesicular stomatis, mainly caught in summer and autumn. Usual symptoms incl. fever, loss of appetite, sore throat and mouth, swallowing difficulties. In 2 to 3 days lesions in mouth and then fingers/hand, sometimes onto feet, buttocks, arms, less ofen face.
The virus that causes it is one main one - coxsackievirus which is an enterovirus. Incubation 3 to 6 days, duration about a week - treatment is only symptommatic as it is viral, recurrance unlikely but possible - so you were right. No none serious complications though.