COVID-19 PCR Testing Explained

A PCR Test will determine if you are actively infected with COVID-19.

What is a PCR Test?

PCR tests are how testing for current infection of COVID-19 works. PCR, or Polymerase Chain Reaction is considered by the CDC to be the gold standard for COVID-19 testing. PCR is a molecular diagnostic test in which viral DNA is obtained from samples from the upper and lower respiratory systems such as nasopharyngeal swabs, oropharyngeal swabs, or saliva. Small amounts of DNA are extracted from patient samples and then amplified exponentially via thermal cycling until there is enough material to be detectable using fluorescence.

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Bloom COVID Testing provides convenient appointment scheduling to help limit patient to patient contact and reduce wait times. 

PCR Testing FAQs

PCR testing is more accurate than rapid molecular or rapid antigen alternatives. PCR testing of SARS-CoV-2, the virus that causes COVID-19, is ideal for individuals, employers, or companies that need to be confident in the accuracy of their results.

A PCR test is performed by extracting SARS-CoV-2 DNA from the upper or lower respiratory system. The viral DNA is extracted from the specimen and the necessary building blocks are added to the DNA to allow for amplification via PCR. Probes are also added that allow the DNA to be detectable by fluorescence. The material is placed on a thermocycler that uses temperature cycles to amplify the DNA exponentially using a three-step process of denaturation, annealing and extension.

  • Denaturation: double-stranded DNA templates are heated to separate the strands.
  • Annealing: short DNA molecules called primers bind to flanking regions of the target DNA.
  • Extension: where the DNA polymerase extends along the template strands.

During this process every DNA strand creates two DNA strands and results in an exponential increase of DNA. Fluorescent probes are released during this process that allow the detection of the SARS-CoV-2 virus spectroscopically.

Visual chart helping explain how a PCR test is done

According to the CDC, the standard turnaround time (TAT) for PCR testing of COVID-19 is approximately 3-11 days. Although the test itself can take as little as 6 hours, high sample volumes can cause labs to be backed up and can greatly extend the average TAT. Private high throughput labs offer a faster alternative.

 

At Bloom, we have partnered with the finest laboratories in the country to provide you with the fastest turn around times in the industry for PCR testing. Bloom customers can expect results for PCR testing in 2-3 days. 

PCR tests determine if an active viral infection is present. When a virus is infecting a host organism it produces viral antigens. A viral antigen is a toxin given off by the virus that triggers an immune response in it’s host. An antibody is a protein component of the immune system that has a hypervariable region that binds to antigens and neutralizes them. Chart explaining how a covid19 PCR test differs from a antibody test After exposure to an antigen, antibodies continue to circulate in the blood providing protection from future exposure. The most prevalent and long-lasting antibody is IgG which can remain in the blood serum for over 6 months. The presence of IgG indicates recovery from the virus. The next most abundant is IgM which indicates an initial exposure to the antigen.    Most antibody testing platforms with FDA EUA’s are testing for IgG or Pan-Ig, total immunoglobins, while many intend to extend their platform to include IgM or differentiate between IgG and IgM, IgM has been documented to only remain in the blood for as little as 4 days and has been determined by many to have little clinical value. However, from a patient perspective, differentiation of antibodies especially in tandem with viral testing, can offer a lot of information regarding their infection. PCR IgM and IgG Explained

How Your PCR Testing Process Works

Our COVID-19 PCR test is designed to provide convenience and accuracy to as many people as possible. Our office and mobile teams offer the highest-quality testing capabilities on the market so you can get back to work, back to life, and back to health as quickly and as safely as possible.

Sample Collection

Saliva or nasopharyngeal (NP) samples are collected for PCR testing. Saliva is a non-invasive, self-administered specimen collection. NP samples are collected by a certified health professional (CHP). For same day results, nasal specimens are collected for point of care (POC) rapid molecular COVID-19 screening.

Sample Processing

The POC rapid specimens are put through a chemical reaction and then analyzed using an on-site analyzer. PCR specimens are transported to a laboratory for the highest quality and accuracy in testing.

Results via e-mail

Once the analysis is complete, test results are sent to your e-mail where they can be viewed and downloaded.

What Your PCR Test Results Mean

According to the CDC: If you test positive for COVID-19:
  • Stay home except to get medical care.
  • Separate yourself from others. Stay in a specific room and away from other people in you home. If possible, use a separate bathroom. If you must be around others, wear a mask.
  • Get rest and stay hydrated. Take over-the-counter medicines, such as acetaminophen, to help you feel better.
  • Monitor your symptoms carefully. If your symptoms get worse, call your healthcare provider immediately.
    • Stay in touch with your doctor. Call before you get medical care.
    • Your local health authorities may give instruction on checking your symptoms and reporting information.
    • Seek medical attention if you experience any of the following symptoms:
      • Trouble breathing
      • Persistent pain or pressure in the chest
      • New confusion
      • Inability to wake or stay awake
      • Bluish lips or face
    • If you have a medical appointment, notify your healthcare provider ahead of time that you have or may have COVID-19.
Testing negative for does not mean that you cannot get COVID-19 in the future. Learn how to protect yourself, and others from COVID-19:
  • Socially distance by avoiding being within six feet of other people.
  • Wash hands often for at least 20 seconds
    • Before eating or preparing food
    • Before touching your face
    • After using the restroom
    • After leaving a public place
    • After blowing you nose, coughing, or sneezing
    • After handling your mask
    • After changing a diaper
    • After caring for someone sick
    • After touching animals or pets
  • Cover your mouth and nose with a mask when around others
  • Cover coughs and sneezes
  • Clean and disinfect
  • Monitor your health daily
According to the CDC, if you test negative for COVID-19 by a viral test, you probably were not infected at the time your sample was collected. However, that does not mean you will not get sick. The test result only means that you did not have COVID-19 at the time of testing. You might test negative if the sample was collected early in your infection and test positive later during your illness. You could also be exposed to COVID-19 after the test and get infected.