Information You Need: Testing Purpose & Tests Available
What is the main purpose of a diagnostic test?
- There is more on this topic coming soon, but receiving a negative diagnostic test should not be used as an “okay” to get together with family and friends or attend holiday gatherings. Negative diagnostic tests do not 100% guarantee that someone does not have COVID-19. However, in conjunction with a two week self-quarantine, a negative test can be a good indicator that a person does not have the virus – but there is always a certain level of risk.
- Some testing centers are also turning away people who have not had a known COVID-19 exposure or who do not currently have symptoms.
Can I test out of quarantine?
- The CDC recently changed their guidelines on quarantine. While they still strongly recommend that most people quarantine for 14 days, they recognize this can be very challenging. Under some circumstances people can be released from quarantine after 7 days with a negative test in the previous 48 hours and NO symptoms. It is ALWAYS BEST to quarantine the full 14 days to reduce onward transmission. But if there are ample tests (which is not really the case right now with soaring numbers), it can be a possibility for some people.
What tests are currently available?
Three major tests are currently available for COVID-19: the PCR test, the Antigen test, and the Antibody Test. The differences between the tests can be difficult to differentiate – especially because each test goes by a few names. The table below outlines how the tests differ from one another. To be sure of what test is best for you, or what test you received previously, consult a healthcare professional or the organization who provided the test.
Viral (Diagnostic) Test | Viral (Diagnostic) Test | Prior Infection Test | |
What are the available COVID-19 tests? | PCR Test | Antigen Test | Antibody Test |
What other names are these tests called? | Diagnostic test Molecular test (some molecular tests can be rapid) Viral test | Diagnostic test Rapid test | Serologic test Serology test Blood test |
What does the test tell you? | Whether or not you currently have a COVID-19 infection | Whether or not you currently have a COVID-19 infection | If you have had a previous COVID-19 infection |
What is the test detecting? | Genetic material of the virus | Specific proteins on the virus’s surface | Antibodies created by your immune system in response to the virus |
How accurate is the test? | Highly accurate | A positive result is highly accurate A negative result may need another test | Fairly accurate; two antibody tests are recommended for more accurate results |
What sample is taken? | Most commonly a respiratory swab Usually taken from the nose or throat) A few tests use saliva | Respiratory swab Usually taken from the nose or throat) | Blood sample Usually taken from a finger stick or blood draw |
How long do results take (on average)? | 1 day or up to 1 week | 1-3 hours | 1 to 3 days |