The best, most accurate test for diagnosing COVID-19 is a nasal swab PCR test. This test involves using a q-tip-like swab to collect a sample from your nose. The sample is sent to a laboratory for analysis and results are typically returned in 1-4 days.
Rapid COVID tests use either a nasal swab or a saliva sample and can give results in 15 minutes to one hour, but are not as good at detecting COVID-19, particularly when you do not have symptoms. Some rapid tests that you administer yourself are available online and through local retailers. If your rapid test is positive, then you can be sure that you have COVID-19. If your rapid test is negative, it is still possible that you have COVID-19. It is recommended that you get retested using a laboratory PCR test if your rapid test is negative and you have symptoms or COVID or have recently had close contact with someone who has COVID.
If you have symptoms of COVID-19: stay home and isolate from others while awaiting your test results, regardless of vaccination status.
If you were in close contact with someone who tested positive for COVID:
If you are up to date on your COVID vaccinations: wear a mask around others and monitor for symptoms while awaiting test results. You do not need to quarantine.
If you are not up to date on your COVID vaccinations: stay home and wear a mask around others in your household for at least 5 days. Continue to monitor for symptoms and wear a mask in public from days 6-10.
No. A COVID test might be negative even if you have COVID-19 if you test too early or too late after infection, or if the sample wasn’t collected properly. Keeping in the mind the time it takes to develop disease after exposure (incubation period), the best time to get tested is 5-7 days after the day you might have been exposed. For example, if you have dinner with a friend on Friday who goes on to test positive, you should count 5-7 days starting Saturday. This means you should take a test on Wednesday, Thursday, or Friday. Testing earlier than Wednesday increases the chance that your test will not be accurate.
Check with your local health department for information on quarantining if you have been in contact with someone who has COVID-19.
If your COVID test is negative and you have symptoms of COVID-19, you should continue to isolate until at least 24 hours after your symptoms are gone.
COVID tests are highly specific. This means that if you test positive for COVID by any type of test you are infected with COVID-19 and should isolate for at least 5 days from the onset of symptoms or positive test. If your symptoms are resolving after 5 days you can discontinue isolation and wear a mask in public from days 6-10. If after 10 days you still have symptoms, you should continue to isolate until at least 24 hours after your symptoms are gone.
In rare cases, a person may continue to test positive by COVID PCR test for up to 90 days after having COVID-19 even though they are no longer contagious. For this reason, it is recommended that you do not take a COVID-19 PCR test within 90 days of testing positive unless you have symptoms that cannot be otherwise explained.
A blood test that detects antibodies to COVID-19 will not tell you whether you are currently infected with COVID-19. This test may tell you if you had COVID-19 in the past. A positive antibody test does not mean that you can’t get COVID-19 again. A negative antibody test does not mean that you did not have COVID-19 in the past.
If you are vaccinated, an antibody test may be positive because your body has generated an immune response to COVID. Vaccines also protect you from COVID by triggering other types of immune responses that are not detected by an antibody test. For this reason it is not recommended that you obtain an antibody test as it does not accurately indicate your level of protection against COVID.
The best way to protect your friends and family from COVID-19 is for everyone who is eligible to be vaccinated. If you are not fully vaccinated, or if you are fully vaccinated in an area of high COVID transmission, additional precautions are necessary when visiting with people outside of your household.
If you and your friends and family are fully vaccinated you do not need to test or quarantine before visiting with one another. However if you are coming from or traveling to an area where COVID-19 transmission is high, you should consider spending time together outdoors and wearing masks and physically distancing indoors. This is because vaccinated individuals may still be infected and spread COVID even though protected from severe disease.
If you and your friends and family are not fully vaccinated, get a COVID test approximately 3 days before seeing one another, and isolate while awaiting test results and before seeing them. Even if you test negative, it is not a guarantee that you don’t have COVID. It is still necessary that you follow all precautions: everyone should wear a well-fitting mask and maintain at least 6 feet of distance from one another. It is strongly recommended that you spend time together outdoors instead of gathering indoors if possible.
If you or your friends or family are experiencing symptoms of COVID-19, you should postpone your visit and get a COVID test.