When should you get a PCR test for Covid19? Prime times include when you have known or suspected exposure to the virus, when you experience symptoms, or when you are infected with the virus. Regardless of when you get the test, it is crucial to choose the right one for your needs. This article was originally published at The Conversation under a Creative Commons license. It is reprinted here with permission.
COVID-19 is a coronavirus disease caused by a virus called SARS-CoV-2. This test detects the presence of this virus by using a technique known as a polymerase chain reaction. This method involves taking a fluid sample from a nostril to identify any present genetic material. The sample comes from the back of the nose and the mid-turbinate.
Process Used TO PCR Test for COVID 19
The process used to PCR test for Covid-19 is similar to that of a PCR. A test tube is dipped in a sample, and a capillary line is drawn from the nasopharynx. The sample is drawn to a strip coated with antibodies that bind to SARS-Cov-2 proteins. If the samples contain SARS-Cov-2 proteins, they show a coloured line, indicating infection. The downside of this test is that it requires confirmation. The turnaround time is usually very short, and the results can be reported within 15 minutes.
This test is more sensitive than the antigen test. It can detect very small amounts of coronavirus in a specimen. Unlike an antigen test, which can only detect the virus, PCR is highly sensitive and can confirm an infection. Even if the patient is no longer contagious, the PCR can detect this virus. A false-negative result is more common than a false-positive.
Genetic Material
A PCR test for Covid19 detects the genetic material of the virus. The results of the PCR test are the most reliable way to confirm an infection. Infection with the coronavirus can lead to fatal complications, but a PCR test can also be positive. A negative PCR test can only detect dead viruses. If the virus is already present in body fluid, the blood sample can cause death.
PCR tests have their limitations. While a positive result indicates that a person has been exposed to the virus, it does not mean that the person is infectious. A negative result means that the person does not have the disease. A positive test does not necessarily indicate that the patient is infectious. It is inaccurate because it cannot detect a virus that has already been dead. It may be a false-positive test because the sample contains dead copies of the SARS-Cov-2 gene.
Positive Result
A PCR test will not confirm an infection, but it can be a good way to confirm that a person has been infected. Although a positive result can be interpreted as positive, it is better to take a positive result over a negative one. In this case, the patient will have to return for a second PCR test to be sure they are not infected.
PCR tests are similar to rapid tests administered by the same doctor. A nasopharyngeal swab is used to extract the viral DNA. Typically, a PCR test will detect the virus during its infection or even infection. The lateral flow test is more accurate and provides a more reliable diagnosis. However, this test is not as reliable as a PCR test.
Final Thoughts
Rapid antigen tests are similar to PCR tests but are not the same. A rapid antigen test collects a nasal secretion sample and examines it for protein fragments, or SARS-Cov-2, in the sample. These tests can provide quick results within fifteen to thirty minutes but are not as accurate as PCR. They require a lateral flow test to detect dead viruses, making them less useful.
PCR testing is more accurate than an antigen test used to identify the live virus. The antigen test is not specific for the virus but will give a result only if it contains the virus’s genetic material. During a COVID-19 viral infection, the antigen is shed from the respiratory tract, gastrointestinal tract, and esophagus. The viral DNA is then released from the respiratory tract, so the patient will most likely have symptoms of the infection.
