Does this happen to anyone else?

I have a related problem and have had it my entire life.

I often feel totally exhausted for unknown reasons and it lasts about an hour.  I recover very quickly after that.

I know this is three years old but stumbled upon it as it a"related" post to a current one I was reading.

I quite often get ill and recover very quickly,I work outside all the time,my work is very manual and at age 55 I weigh nine and a half stone.I do however smoke a lot(addiction) and eat fairly well although don't enjoy fruit and tolerate vegetables. 

My doctor told me I am one of the fittest 55 year olds she has met.

I usually get summer and then winter colds. They start off quite pronounced but then settle with little effect but they linger, If I feel unwell I eat plenty regardless of appetite,I believe eating fuels the body to fight off illness.

I rarely have days off sick and even when feeling very ill I usually go in if I can. I must add that I am not formerly diagnosed with ASD but truly believe I am and always was. 

I don't think this is necessarily autism related. It sounds like you simply have an efficient and healthy immune system that is in good working order - like a child's!.  Your immune sytem responds to the threat by unleasing an inflammatory response, manifested as symptoms. The symptoms are good, even though they are perceived as horrible - they are the by-product of a healthy immune system. The bugs are cleared out of your system quickly,  and so  there is a prompt return to health, instead of a sluggish and prolonged response - the signs of an inefficient immune system.

You say you eat a healthy diet and look after yourself - this will facilitate a healthy immune system.

Many people don't look after themselves when they are sick, which only keeps them ill for longer. My immune response seems similar to yours: on the rare occasions I get ill, I will suddenly feel tired and headachy. If it is a stomach bug, I am sick only a few times, and two hours later I am fine!. This happened once when a severe bug was going round - other people were wiped out for days! My illness only lasted a couple of hours.

Everyone, though, has a different immune response, and healthy immune systems all vary. By sleeping when ill and avoiding work, you hasten your recovery.

Your ability to bounce back could be because you are looking after yourself properly, your diet is sensible and you are not denying yourself sleep. 

stress (this goes with AS) is likely to lead to physical ailments so there is an autism aspect to this but I think you are demonstrating that actually AS can lead to more reliable , staff who care more (even obsess On occasions) about things like health.

one reason for asking about diet was me trying to work out what might help me - recently diagnosed at 56 - reduce the incidence of meltdowns etc.

My employers haven't made any fuss so far and I'm not often ill. I don't have joint problems and the aches were down to a flu-type bug which has been going round the office.

I do get stressed, as do we all, and sleep sorts it out often, but I also sleep a lot when sick. I have a good diet and no problems with allergies or intolerance.

I was really asking if anyone else gets ill quickly and then recovers quickly. For instance I had a bout of awful flu last year. I was really ill but once recovered I was instantly back to normal unlike my colleagues who were sick for longer than me and also complained of weeks of subsequently feeling below par.

This is also relevant because I'm writing a guide for employers of autistic people and wondering if i should mention this in it.

Age is more likely to be a factor. Joints begin to become more sensitive and more responsive to any change in circumstances. Other response centres affected when ill in the past may be more likely to show signs when feeling under the weather.

The thing is, without wishing to belittle your own experience, but rather to castigate your employers, this is quite common.

So your employers ought to wise up about such things, save themselves a lot of employee relations problems.

I have two thoughts on this. do your illnesses follow after periods where you have been very busy, working particularly hard or when you have had a particularly social time? Getting completely exhausted is a thing that can creep up on an autism sufferer. A duvet day or a good nights sleep can sort this sort of incident out.

My second thought is whether you have looked at food intolerance - some food additives and drugs (e.g. aspirin) can have a huge impact on some people. 

Your absence pattern sounds unfortunate - you might like to look at the Bradford factor which is a measure used by employers to identify people who may be swinging the lead.

Can you talk to your employer and say that you are not sure what is going on but that you are aware of it. Can you apologise to them and say that you can understand that it doesn't look great? Have you had more or less days off than average?