Refusal to wash, any advice?

Hello everyone. This is my first time here and I have been reading some previous post on this topic, as I know there are lots… I did find a really handy tip for shampoo caps which I was allowed to use once and worked really well, but I can’t find any comprehensive solutions.

I have become a carer for my brother who has lived with me for the last 8 years. He didn’t originally move in because of health issues, but he has COPD and has now deteriorated to a situation where he can barely walk around indoors, due to breathing issues. He never goes out unless by ambulance for appointments,

Let me first point out that he has never been diagnosed (I don’t think they knew much of this in the 50s) but is most certainly on the autistic spectrum, some sort of aspergers I think. Due to this he views things very differently from most people but is highly intelligent and his mind is very sharp. He has never been a fan of washing as I recall, even before becoming ill. Now he has problems with toileting and cannot clean himself properly. Whilst not incontinent, he often has soil residue that seeps through his underwear and trousers and leaves marks wherever he sits (I put down puppy pads). He continues to live in the same clothes that have been soiled multiple times, not undressing for sleep, 24/7 Showering has always taken too much energy for him, so hasn’t showered in 3 months, but despite buying bedbath wipes for him, which I believe he could cope with, he refuses them and creates an argument if I press the point. He won’t use these himself or allow me to help, he just won’t address the issue.
He works freelance from home on an adhoc basis and is glued to his PC when he is not in bed resting. He won’t allow me to change bedding so I can only do this after a 3 month long fight to try to get him to wash and change. I am running out of the mental energy for this fight to be honest. I am only at home now as been furloughed so am normally at work, and he just doesn’t eat or drink till the evening when I get home. He doesn’t always even eat the sandwich I leave. Even now he doesn’t eat much, although I am home. Social services have offered carers but that all came to nothing, mainly I believe because they left it to him to phone their follow on line after initial home visit, and I don’t think he’s bothered. I don’t think he’d always allow them in even if he did have carers to be honest. It’s just as well in current climate, but ultimately they seem to think that because I am here we are coping, but although he’s happy with the situation, I am not. Now the smell of faeces is becoming a real problem and I have decided not to even enter his room anymore and am leaving his cups of tea outside. Anyone have any ideas? I really do feel his refusal to wash is as much about his mental state as his physical one - he has also been on antidepressants for several years.
Sorry for long post,

He needs to move out.
He has absolutely no right to live in your home. As it’s YOUR home, it’s YOUR rules.
If he’s bright enough to work (my son is brain damaged) then he needs to understand that, like it or not, he needs to conform with some rules.

You have allowed him to do this for too long.
He really doesn’t care two hoots about you or your feelings.

The only way you are going to get out of this ghastly situation before he dies is for YOU to do something. He won’t unless you give him a real shove.
Your home should be your haven, arranged how you like, smelling how you like etc.
You can’t have friends round like this.
We are all responsible for our own happiness. Time for you to stand up for yours. No one else will!