Savvy Senior: Can COBID-19 cause shingles?

Dear Savvy Senior,

How effective is the shingles vaccine and what is the CDC recommendation for getting it? My older brother and sister, both in their fifties, got COVID a few months back followed by shingles. Do you know if there is a connection between these viruses, and would the shingles vaccine have protected them?

Scared of shingles...