[walterbell]

Yes, but they could have other risks due to existing medical conditions. It's an arms race between the speed of replication of the invading virus, and the immune system's ability to respond. Existing conditions add many complications.

If they interact regularly with family and were long exposed to commonly circulating viruses (e.g. from kids), they would have a resilient/diverse immune system. This assumes a healthy diet with no deficiencies (Vitamin C, D, Zinc).

Another complicating factor is the content of flu vaccines.

[Fjolsvith]

Are you saying that flu vaccines could make us more susceptible to COVID-19 and other coronavirus infections?

[walterbell]

The term "flu vaccine" is as meaningful as "glass of liquid". Depends what's in the glass. The content of vaccines vary across geographical regions and their very purpose is to interact with the immune system. The precise contents of previous vaccines should be tracked and analyzed in studies of elderly immune system responses to SARS-Cov-2.