Chatted with my sis on the phone yesterday, and she told me she's one among only five retired docs in her area with the necessary experience in ITU. She's ready to help if needed, and as she points out, it will be the 'frontline' employed docs who are at risk from infection and who will need replacing from the Oldies' Army.
She's remarkably strong and feisty for her age and I reckon she could do it. But it is worrying nevertheless.