What are antigen tests? Is it required to retest negative results with a PCR test?

Antigen diagnostic tests quickly detect fragments of proteins found on or within the virus by testing samples collected from the nasal cavity using swabs.

Negative results should generally be treated as presumptive, do not rule out SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions, including infection control decisions. If necessary, confirmation with a molecular assay for patient management may be performed. Negative results should be considered in the context of a patient’s recent exposures, history and the presence of clinical signs and symptoms consistent with COVID-19, and should not be used as the sole basis for treatment or patient management decisions, including infection control decisions.

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1. What is COVID-19?
2. How does COVID-19 spread?
3. How severe is COVID-19?
4. What are the symptoms?
5. When do I seek medical evaluation and advice?
6. How can I protect myself from COVID-19?
7. How is COVID-19 treated?
8. I may have been exposed to coronavirus. What do I do?
9. Should I wear a face mask in public?
10. Who should get tested?
11. What has changed about testing availability?
12. Where can I get tested?
13. Can individuals visit Placer County Public Health and test for coronavirus?
14. I do not have health insurance and do not have a doctor. If I think I have contracted COVID-19, what do I do?
15. What is a quarantine and why is it used?
16. Is quarantine different from isolation?
17. How does self-quarantine work?
18. What is the current situation in California and Placer County?
19. What can I do to prepare for COVID-19?
20. What is Public Health recommending to help contain the spread of COVID-19?
21. Can you tell me more about what areas to avoid?
22. What should I do if someone known to be exposed with coronavirus visits our facility?
23. Where can I get an antibody test?
24. How can I contribute to help those impacted by COVID-19?
25. How can I access food, mental health, unemployment or other resources?
26. What are antigen tests? Is it required to retest negative results with a PCR test?