By Dr. Mallika Marshall

BOSTON (CBS) – The Centers for Disease Control and Prevention has updated their COVID-19 isolation guidelines after criticism over the new shorter policy.

The CDC now says the best approach for people who test positive is to isolate for five days. After that, you can take a rapid test, but it is not required.

If you are positive, you should continue isolating for the full 10 days. If you are negative, you can end isolation but continue wearing a mask around others until day 10.

Dr. Mallika Marshall has some answers to questions about the changes.

It’s hard to make sense of these new recommendations. They say that the new five day isolation guideline is based on science.

Studies have shown that people are most contagious in the two days before they develop symptoms until three days into the illness. So by day five, you’re much less likely to pass the virus onto others. That said, you can still be somewhat contagious which is why they are still suggesting you wear a mask in public for an additional five days.

So what specifically are people now being asked to do?

Anyone who tests positive needs to stay home and isolate themselves in the home for at least five days, whether they’re vaccinated or not.

If you’re feeling better five days after your symptoms begin, meaning you have no fever, no vomiting and barely any cough, you can come out of isolation as long as you continue to wear a mask around others for an additional five days.

The confusing part is that the CDC says people can choose to do a rapid antigen test at five days as a precaution, but if positive, it means you’re still contagious and should continue to isolate for another five days.

Why do you think they are hedging on whether you should test at five days to check how infectious you are?

I think for a couple of reasons. The CDC knows that many people have not been staying home for the full 10 days as originally recommended, so if they know they can leave after five days, perhaps they’ll be more compliant.

The other thing is we just don’t have enough testing available right now to screen everyone five days into their illness. Hopefully, this will change, but the nation is still woefully short on testing capability.

Would you still recommend a 10-day isolation period?

I would say if you can stay home for 10 days, that’s ideal. But if you’re feeling much better and you have to return to work, make sure you wear a mask around others for another five days. Don’t take it off in public for any reason, including to eat or drink.

Dr. Mallika is offering her best advice, but as always, consult your personal doctor before making any decisions about your personal health.

If you have a question, email her or message her on Facebook or Twitter.

Dr. Mallika Marshall