Our neighbour is in his 70's, single, no nearby family and not in the best of health (COPD), we told him to knock on if he needs anything and gave him our phone numbers.
My PILS are similar age but far better health. They live 2 hours away but my SIL lives 10 minutes from them, so we know they'll be looked after.
Check your neighbours please. Same as you would in bad weather.