And you're not going to get a diverse opinion on MN because of the disproportionate amount of users with health anxiety on here, just to add.
I do not have health anxiety, but I do have three acquaintances who are still incapacitated after having contracted Covid in March. All of them are below retirement age, none of them would have been in the shielding category; all of whom are suffering from multi-organ damage. They're not dead, I grant you that. But it's not much of a life.
If an OP had come on MN a few months ago and talked about protecting a small baby from a cold sore, I suspect you wouldn't have felt the need to point out that very few people die from cold sores, and that lots of people only get symptoms from cold sores when their immune system is low. Some people do seem very invested in the non-existence of Covid.
Yes, I get the need to protect the economy and provide education. But not holding the baby isn't going to shaft the economy.
The OP has not been banned from seeing her grandson, just from touching him for the time being. Yes it's heart-breaking but so I suppose is not being allowed to kiss a baby/having to ensure his hands didn't touch your face if you had a cold sore: that would also require keeping him at a certain distance. The distance does not appear to be huge in the present instance as the baby does in fact inadvertently touch his grandmother from time to time.
In other words, this is a grandmother who is allowed access at quite closer quarters to her grandchild, but is asked to observe the kind of distance you would if there was a risk of her transmitting a cold sore.