With the surge in omicron variant cases, it seems everyone has the same idea: test for COVID-19 to be as safe as possible around family members during the holidays.
Well which one should you take and why?
NBC 7 spoke to Corinne McDaniels-Davidson, an epidemiologist and director of the SDSU Institute for Public Health, who compared the two.
A PCR test can tell you if you have contracted the virus at that moment you were swabbed. McDaniels-Davidson said these are best to detect early infections.
“So if someone just got infected, but they’re not yet infectious, PCR tests can pick that up, but the antigen test won’t,” said McDaniels-Davidson.
PCR tests are free at county and state testing sites, but it often takes a few days to get results. A privately run site can cost upwards of $100 per test.
“So when you get them a day, two days, or even three days later, they are no longer necessarily relevant and you may now be infected but not know it," said McDaniels-Davidson.
The rapid antigen tests determine if you are infectious. And while they're quick and easy, they're less accurate than PCR tests. Experts say it’s best if you use them regularly for travel.
“So, if you have a gathering at 6 p.m. tonight with your family and you want to be indoors together and you’re all vaccinated, then you can test right before you go. And anyone who is positive, should not go. Or if anyone is not feeling well, even if they’re negative, they shouldn’t go,” said McDaniels-Davidson.
Antigen tests are available over the counter if your store has them in stock, but they can get pricey. But you get your results in minutes.
And as the omicron variant spreads, the time in between contracting the virus and being infectious could change.
“We do know more than we knew a couple of weeks ago and it does look like the incubation period has shortened.” Said McDaniels-Davidson.
Bottom line: No test is best. Doctors say choose which one is right for you.