I love how posters are pilling on to call the OP needy, immature and childish for wanting a cuddle...all while ignoring the implausibility of the infection control argument.
Putting the infection control issue aside, there’s lots of other reasons which have all been covered.
Risk of someone falling off the bed which is meant for one. Now you have 2 patients, not one and a fuck tonne of paperwork.
While there are special beds for high weights, normal beds are up to the challenge but not so much for 2 people combined and you risk damaging them. You can’t have a system where some patients can have visitors on beds and some can’t dependent on weight of patient and visitor, you need a blanket rule. That’s one person in the bed, the patient.
You are meant to have unhampered access to the patient at all times for routine and emergency purposes. Having someone else on the bed makes that hard.
If someone is that ill then there’s generally a bit of equipment involved which can be easily disturbed by someone else lying with the patient. I would argue if you don’t have this issue, you are not that ill and would question the need to have someone in bed with you for comfort. Also, in my experience, patients who are genuinely that ill don’t tend to give a flying fuck about anything and are not needy in that sense.
The other thing is, even if it is a private room, it’s still considered a public space. Others have to be around you to do their jobs. Most people are very uncomfortable dealing with patients sitting there cuddled up in bed. It’s an inappropriate PDA and lacks social sense and boundaries. In short, it’s fucking weird.
You also need to put a boundary in place as some people have absolutely none and people do have sex in the bed. We have all seen this. Much easier to have a blanket patient only on the bed rule. Sad but true.
Terminally ill is a different matter. Generally if at the point someone can climb into bed with them they have no equipment and are just being made comfortable. It’s also one sided generally, very different to two people in a PDA on a bed. It’s understandable and not weird.
Paeds are also a different matter. Weight issues would rarely be a factor. Inappropriate behaviour not a factor. Kids have comfort needs the average adult should not so are more manageable, treatment compliant and less work if secure and that often means an adult in the bed with them. Even if factoring in infection control, then all of this overrides. Equipment can be tricky but again in my experience if they are really sick they are too sick to compute if someone’s in the bed with them or not so this rarely happens and most acute environments you could not get in the bed with them due to access and emergency so not an issue. Of course if they are dying, it all becomes moot and remove everything possible and hop on in.