@loveyouradvice tried to answer your PM but my OS is old, and neither Firefox nor Safari would allow my message to post - so I'll put it here:
"I'm so sorry to hear that. It's a really scary time, and made worse by having to just stand by, not being able to do anything to help.
Like you, I can't get in and see what the home is doing. As far as I know, they kept everyone isolated in their rooms, then just looked after everyone as normal. My Dad is in a nursing home, so there are two nurses on duty during the day and one at night (it's a small home). I presume they would be monitoring his breathing, and would be ready to test his oxygen levels (I know they have the capacity to do that)
When you've recovered from the initial shock, make sure the home know that you want to be involved in all decisions. You should be able to ask them what they're doing to look after her, how they are monitoring her, ask about what happens if her condition deteriorates. Make a list of everything you want to ask before you telephone, and note down the answers as you get them. It's difficult to remember things when your head isn't straight.
Does she have capacity? Do you have Power of Attorney for health matters?
Think about who you can talk to to get updates on her condition - you may need to ask for someone, eg a nurse, by name. Our home usually get one of the nurses to the phone, but if you do get a carer, they're inclined to say "he's doing fine" whatever the actual situation is.
On the practical front - and this is all theoretical, we hope it doesn't come to that - you should have the DNAR conversation - would she want to be resuscitated if her heart stopped. There's no guarantee she would be, as it's a brutal process and likely to be too much for a frail older person. And the wider discussion of whether she wants to go to hospital if she has difficulty breathing. You would want to ask her chances of recovery in hospital and balance that against palliative drugs and more chance of a final visit if still in the home.
But remember - one figure I've seen for mortality rate of 80-89 year olds testing positive is 14% - and even that high figure means, not just that she's more likely to survive, she's more than 6 times more likely to survive.
What I've read on the internet suggests days 5-10 are critical. If she's still OK 10 days after any symptoms started, it's good news.
My father didn't show any symptoms apart from being far more tired than normal, and he was off his food - uncharacteristic for him - so they think he probably lost his sense of taste (and therefore smell). He tested positive two weeks running, then his next test was negative. He's 98, and male - men are more likely to become seriously ill than women.
Sorry I can't be any more helpful, I haven't been able to see what was going on, and I don't have any medical training. Do ask the "elderly parents" board for support while you're waiting through this worrying time. There's nothing you can do, so try to keep yourself busy with other things. And keep reminding yourself she's much better off in the home being monitored by staff who know what they're doing and what to look for than she would be at home with you.
Keeping fingers crossed for you."