If you unblind patients, that will change their behavior and alter your results. If they told her she had the vaccine, she'd be more likely to go out and take risks. Conversely, if they told her she had placebo, she'd probably stay in and take less risks. Overall, this would lead to a dramatic reduction in the power to observe an actual protective effect, as vaccinated would be riskier and unvaccinated would behave safer.
Hang in there, she is doing a good service, I hope you are both well!
Yes, I understand the purpose of blinding. I'm wondering if that purpose still holds once a vaccine is approved and is widely available. Surely for her safety they will unblind her so she knows whether to go get the real vaccine?
Hang in there, she is doing a good service, I hope you are both well!