With the rise in popularity of at-home testing, health experts are saying it's important to remember that these COVID-19 antigen tests aren't perfect. They may show false negative results if you don't take them at a certain point in your infection.

At home antigen COVID-19 testing is becoming the go-to for the coronavirus, with lines at testing sites like Northshore labs dwindling or sometimes disappearing entirely. While the rapid antigen tests are quicker,  health officials are warning with Omicron, you can't always trust a *negative* rapid result.

"The antigen test are not as sensitive, so it is possible that you do have it and it will return a negative result," said Scott Oxarart with the Washoe County Health District.

While  there is a time and a place for rapid antigen tests… it's not at the beginning of an infection. With Omicron,  it can be 5 days into the infection before they finally return a positive result… providing a false sense of security while people spread the virus.

"Sometimes it can be user error, sometimes it's not getting enough of a specimen when you stick the swab up your nose, there's all types of things that can happen," said Oxnart.

Health officials do recommend that if you are showing symptoms of COVID-19, but your at home or antigen test comes back negative, it may be a good idea to go and get that PCR test.

"The biggest difference between the antigen test which is the at home tests and the PCR test is that the PCR test is a lot more sensitive, it's able to pick up more of the COVID-19 virus and relay that as a positive test," said Oxnart.

Luckily, the Washoe County Health District has been providing free PCR tests at the Livestock Events Center, and thanks to help from the national guard, have expanded testing availability yet again, with results within 1 to 2 days.  But no matter how you test, it's important to remember that the case count in the community is most likely higher than what is known, as at home positive results do not get submitted to the county.

"We are seeing so many cases right now, it's so far higher than we ever expected or that we ever really thought it would get, so if there's more it just makes the precautions and the recommendations that we are saying even more important."

If you do want to sign  up for a PCR test through the county, they have openings, and you can sign up as late as the night before you need to get tested. You can sign up by clicking here: https://covid19washoe.com/testing/