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What is the difference between a PCR and rapid a test?

Discover the difference between a PCR and rapid test for COVID-19. Learn about the two types of COVID-19 tests and which one may be the best choice for you. Understand the differences between molecular and antigen tests and the role of antibody tests. Find out how to prevent the spread of COVID-19 and where to get tested. Determine which test is right for you and when to expect your results. Stay informed and make informed decisions about COVID-19 testing.

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Although we have been dealing with this pandemic for over a year and a half, COVID-19 testing still poses a challenge.

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Two types of COVID-19 tests: Diagnostic and Antibody

Diagnostic tests can detect an active infection in the body, including the PCR test. A nasal or throat swab or collective saliva collected into a tube is commonly used to collect samples for diagnostic tests.

Verify that the COVID-19 tests you consider are approved in your jurisdiction before proceeding.

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Let's now look at the two types:

  • A PCR test involves collecting a sample at home and sending it to a laboratory to be analyzed.
  • The kit provides everything you need to perform an antigen test and receive your results in minutes.

What do you prefer between the two? It depends, and either could be the best choice.

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Note: The most accurate and sensitive method of detecting the virus, regardless of whether you have symptoms, is a PCR test. PCR results typically take two to three days to arrive at home. On the other hand, a rapid antigen test yields result quickly. If you are experiencing symptoms of the disease, rapid antigen tests are most effective. Even if the results are negative, a PCR test should be performed to confirm the results. Most rapid antigen tests include this information in their package inserts.

Diagnostic tests: Molecular v. Antigen

Different types of diagnostic tests are available:

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  • Molecular
  • Antigen

COVID-19 can be detected in the body using a molecular and antigen test, but their detection processes differ.

Molecular Test

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A molecular test can be used within days of infection to detect COVID-19 virus-specific RNA (or genetic material). It usually takes a little longer for PCR tests to produce results because they are molecular tests. An individual cannot be diagnosed with COVID-19 based on a molecular test. Most molecular tests can be repeated only once.

A COVID-19 antigen test, commonly known as a rapid test, detects protein fragments. Generally, antigen tests turn around very quickly, and they are considered most accurate when conducted on someone with symptoms of COVID-19. They are not always accurate, however. A molecular test may be required to confirm negative results. A COVID-19 antigen test, just like the molecular test, cannot reveal whether you've previously had the virus.

Antibody test

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An anti-COVID-19 antibody test is performed to determine if your immune system has produced antibodies for fighting SARS-CoV-2, the virus that causes COVID-19. Tests for antibodies shouldn't be used for diagnosing an active COVID-19 infection, but they can be used to determine if someone has previously been infected.

After infection, antibodies can take several days or weeks to develop, and they may remain in your blood for several weeks after recovery.

Blood samples are required for antibody tests, and they are usually taken from finger pricks, or blood draws. Depending on the proximity of the laboratory that is processing the blood sample, blood tests can be completed as soon as the same day or may take a few days.

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For accurate results, a second antibody test may be required.

False-negative

A false negative is when a test result is negative, but the patient has COVID-19.

The recommendation is to take a molecular test for confirmation if a false negative occurs with an antigen test. In particular, those who have had a high-risk exposure are encouraged to do so. Within 24 hours, a high-risk exposure is defined as more than 15 minutes of contact within six feet of a COVID-positive individual.

Preventing the spread of COVID-19

Here are the best ways to prevent the spread of COVID-19, whether you're planning a safe gathering, staying safe at work, or simply attending a crowded indoor event:

  • Outdoors is always preferable to indoors when you can do an activity.
  • Please keep your hands clean and frequently wash them. Please do not touch your face unless you are washing them.
  • Avoid crowds.
  • Consider working virtually if possible.
  • Get tested right away if you suspect COVID-19 exposure.
  • Those in at-risk groups need to take extra care.
  • Obtain a vaccination
  • If you have COVID-19 symptoms, get tested.
  • Put on a mask.
  • Social Distance
  • Avoid poorly ventilated indoor spaces.

Where can I get tested? Which test do I require? When will I receive my results?

Especially for us, it is important to know whether we are virus-free as easily and as quickly as possible. The COVID test at home seems to be a convenient solution, especially since some provide quick results.

You can now attend that birthday party you don't want to miss. You get a quick test, a negative result (hopefully), and then you're free.

Sadly, it isn't as easy as that. In addition, because not all at-home COVID-19 tests are rapid, how do you know which is needed?

"The gold standard of COVID-19 testing remains a PCR test conducted on a nasal or nasopharyngeal sample collected by a medical professional. It may be helpful to do COVID tests at home during this pandemic. Dr. Wesley Long, director of diagnostic microbiology at Houston Methodist, agrees.

We're a year and a half into this pandemic, and COVID-19 testing can still be perplexing at times.

Where can I get tested? Which test do I require? When will I receive my results?

Many of us, in particular, are looking for easier and faster ways to determine whether we are virus-free. And taking an at-home COVID test appears to be a very convenient solution, especially given that some provide rapid results.

A quick test, a negative result (hopefully), and you're free to attend that birthday party you really don't want to miss, right?

Unfortunately, it is not as simple as that. Furthermore, because not all at-home COVID-19 tests are rapid, how do you know which you require?

"A PCR test of a nasopharyngeal, or sometimes nasal, sample collected by a medical professional remains the gold standard of COVID-19 testing. During this pandemic, at-home COVID tests may be useful. "Dr. Wesley Long, director of diagnostic microbiology at Houston Methodist, agrees.

Which at-home COVID test is the most effective?

To begin, ensure that the at-home COVID-19 tests you're considering are approved in your jurisdiction.

It's now time to consider the two types:

PCR test – you collect a sample at home and mail it to a laboratory for analysis.

Rapid antigen test – you collect a sample at home, test it with the kit materials provided, and receive your results in minutes.

Which of the two is best for you? It all depends, and the answer could be either of them.

"Whether or not you have symptoms, a PCR test is the most accurate and sensitive method of detecting the virus. Typically, the results of an at-home PCR test take a few days to arrive. A rapid antigen test, on the other hand, yields results quickly. Rapid antigen tests are most effective early in the course of the disease if you are experiencing symptoms. Even if the test is negative, the results should be confirmed with a PCR test. This information is included in the package insert for the majority of rapid antigen tests.

Whether you're trying to plan a safe gathering, deciding how to stay safe at work, or simply want to take a chance at that crowded indoor event the following are the most effective ways to prevent the spread of COVID-19:

  • Obtain a vaccination
  • If you have COVID-19 symptoms, get tested.
  • Put on a mask.
  • Social Distance
  • Avoid poorly ventilated indoor spaces.
  • Stay away from crowds.
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