As free rapid COVID-19 tests from the federal government begin arriving at Oregon households, many still have questions about at home testing. Here are some answers.
Dr. Katie Sharff is Chief of Infectious Disease with Kaiser Permanente Northwest. She said rapid antigen tests are most sensitive—at about 70%- when a person is symptomatic.
“If you develop symptoms that could be consistent with COVID-19, take it one to two days after your symptoms start.”
Sharff said if you have been exposed, wait three to five days to test—once the virus has had a chance to replicate. She says taking a rapid test too early could result in a false negative.
The rapid antigen test detects COVID-19 when a person has a high amount of viral particles. Sharff explained there’s no amplification with this test and so if you take it really early in the infection, then you might get a false negative because it’s just picking up viral particle shedding.
If you feel sick but get a negative result, Sharff insisted that isn’t a “free pass.” The test should be repeated at home in a couple days. Or, Sharff advised, you should get a PCR (polymerase chain reaction) test to be sure.
“The PCR tests are considered the gold standard for detecting the virus,” Sharff said. “These are performed in the laboratory and involve making many copies of the virus’ genetic material. That allows these tests to detect small quantities of virus and to detect them sooner.”
And what about testing positive for coronavirus at home? Dr. Sharff was unequivocal. “A positive rapid antigen test right now, with the amount of COVID in the community, is considered a ‘true positive’ and you do have COVID,” she said.
That’s when it’s time to notify contacts, isolate and heal.
It’s also important to notify your doctor and to self-report a positive at-home rapid antigen COVID-19 test result to a health authority. For example, on the Lane County Public Health website the there is a form “Reporting a Positive Home COVID-19 Test”
Lincoln County Health and Human Services website also has an online form for self-reporting after a rapid test At-Home COVID-19 Test | Lincoln County Oregon
Every residential household in the United States can order one set of four free at-home tests from USPS.com.
Here's what you need to do to get your tests:
- Limit of one order per residential address
- One order includes 4 individual rapid antigen COVID-19 tests
- Orders will ship free starting in late January
- Visit special.usps.com/test kits
