A World Health Organization representative just advised wearing masks after vaccination. The CDC has a different perspective. We asked public health specialists to weigh in.

Here's what we know about the effectiveness of vaccines for variants of concerns, notably the delta variant, first identified in India and now responsible for more than 20% of new U.S. cases.

While natural infection does seem to provide some immunity, studies suggest that it is short term. Vaccination, on the other hand, provides more robust immunity.

The short answer is — no. Immunology experts say there is little to be gained, for now, from an antibody test, for a number of reasons.

Researchers are looking into several key points: Can ultraviolet light kill the coronavirus, and is it safe to use? Or might your eyes pay a price?

Plus: Can the virus make me sick many years later, like the chickenpox virus does?

Answers to your COVID-19 questions about how to handle Halloween trick-or-treaters, whether it's safe to eat in a restaurant's outdoor bubble and whether you can be infected through your ear canal.