SARS-COV-2 TESTING INFORMATION
What tests are available to test for COVID-19?
There are a few ways to test for the novel Coronavirus (SARS-CoV-2), which causes Covid-19 disease.
1. Testing for active COVID-19 infection.
What kind of tests are available?
PCR testing (done using swab in nose or mouth, or from saliva sample): this tests for viral particles and ACTIVE infection. Samples are collected at the testing site (doctor's office, urgent care, County testing facility) and are sent for testing to a commercial lab such as LabCorp or Quest, or are run at the point-of-care testing site ("rapid" PCR test) - depending on symptoms and test availability. Home test kits are also available. Talk with your doctor about which test is most appropriate for you.
Antigen testing (done using swab in nose or mouth): this test is less sensitive and less reliable than the PCR test, but can be done in certain settings for rapid screening to detect ACTIVE COVID-19 infection.
What does the test result mean?
A positive result means you are contagious to others and should self-isolate for up to 14 days as well as follow closely with your doctor. Please keep in mind there are risks for false-negatives (which is a negative result when actual infection exists).
A negative result may mean that you do not have COVID-19. However, up to a third of PCR tests and up to half of Antigen tests are FALSE NEGATIVES - either because the test itself is not sensitive enough (especially true for Antigen tests) or because the test is done too early in the course of infection (before viral levels are high enough to be detected).
Where can I get tested?
COVID testing is available in doctors' offices, many urgent cares, some pharmacies, and various county testing sites. Home test kits are also available.
Talk with your doctor about the best way/place for you to get tested. This may depend on your symptoms, history of exposure, and specific needs.
LA County is offering free testing to residents of Los Angeles - Click here for information and online scheduling
2. Testing for PAST infection/exposure to COVID 19. This can be done through Antibody or Serology testing (blood test), which tests for antibodies in the blood. The presence of antibodies indicates prior exposure to the virus or to a vaccine against the virus. Antibodies are immune cells that fight infection from pathogens such as viruses.
Usually people produce antibodies or “seroconvert” 7-10 days after exposure to SARS-CoV-2. These antibody tests check for IgM or IgG antibodies. IgM antibodies usually wane after a few weeks of infection, but IgG antibodies usually remain elevated for longer periods of time (typically peak at 14 days after onset of symptoms). Antibody testing is only done on asymptomatic patients, typically at least 3 weeks after onset of symptoms if the patient was symptomatic.
A positive result implies there was exposure to SARS-CoV-2. False positives (which is a positive result in a person who was never exposed) may occur if the antibody testing cross-reacts with those of other coronaviruses (those that have already existed for some time, such as the common cold).
A negative result implies that there was no exposure to SARS-CoV-2, or that antibody levels are no longer detectable. Published data has shown that antibody levels decline within several months after infection.
Indications for Antibody (Serology) testing:
• Patients with suspected prior infection but did not have PCR testing or had negative PCR testing
• Patients with confirmed or suspected Covid-19 and want to donate plasma
• Patients in clinical trials or research
• Frontline or first responders
• Asymptomatic immunocompromised patients (those who are elderly, have diabetes or autoimmune diseases or undergoing cancer treatment), if required by their healthcare facility or treating physician
• Patients scheduled for surgery in combination with PCR testing
• Patients in close contact with high risk patients (immunocompromised or elderly)
Antibody (Serology) testing is not recommended for:
• Diagnosis of active Covid-19
• Low risk, asymptomatic patients
• Healthy children and young adults
• deciding whether to get a Covid vaccine or booster - since we do not know what antibody levels correlate to protection against Covid infection.
The most important thing, regardless of testing results, is to continue to prevent spread of this disease. We can do this by practicing physical distancing, frequent hand washing and staying home as much as possible. If you have symptoms of infection such as fever, sore throat, cough, body aches, shortness of breath, loss of sense of taste or smell, contact your doctor.
Where can I get tested for COVID-19?
Testing for Active infection:
At your doctor's office - Talk with your doctor about the best way/place for you to get tested. This may depend on your symptoms, history of exposure, specific needs, and the availability of various tests.
SMFP Urgent Care - Our doctors are available to evaluate you and do appropriate testing (including COVID-19 testing). No appointment needed:
901 Wilshire Ave, Santa Monica CA 90403
Hours Mon - Fri 8:30 am - 7:30 pm, Sat - Sun 10 am - 2:30 pm
Other locations around Los Angeles: Free testing for residents of Los Angeles County - sites are operated by the City or County of LA, or a partner group. Some are walk-in clinics, and others are drive-up sites. Many offer testing without appointments.
Testing at home:
- Home collection kits for COVID PCR testing - these are available for order online through several commercial laboratories, including LabCorp/Pixel, Quest, and others. These kits allow you to collect a specimen sample (such as nasal swab) at home, and send the sample via expedited mail to a commercial lab that then runs the kit. Turnaround time can be several days, depending on the volume of testing the lab is doing. Most of these kits do NOT require a doctor's order.
Home rapid Antigen test - this is a kit you can purchase online or at a pharmacy for home use. It provides a result within 10-15 minutes, but may not be as sensitive as the PCR tests run through commercial laboratories.
Additional information about home testing can be found on the CDC website.
Schedule an appointment with your doctor to find out how, when, and where to get tested for antibodies.