Who gets vaccinated against Covid-19 first?

There are multiple candidates being tested as a Covid-19 vaccine, but finding a safe and effective one is just the start of the journey to creating sufficient herd immunity. — AP

Whenever a vaccine for the SARS-CoV-2 virus that causes Covid-19 becomes available, one thing is virtually certain: there won’t be enough to go around.

And that means there will be rationing.