What to know about COVID-19 test, PCR of antigen-antibody

We often talk COVID-19 test as it only means one thing. But in reality, the Food and Drug Administration (FDA) for the date emergency response issued an authorization to more than 200 different tests for current or past infection of SARS-CoV-2, recognizes the virus that COVID-19 caused. Recently, the agency has made headlines around the first such approval test that uses saliva samples, the test SalivaDirect aptly named by the Yale School of Public Health. This COVID-19 tests fall into three main categories: PCR, antigens and antibodies. Dr. Aneesh Mehta, head of infectious diseases at Emory University Hospital in Atlanta, Ga service., He broke the differences between them and to keep this in mind when you decide to leave tested. PCR Test Most COVID-19 tests in the US happen polymerase chain reaction technology (PCR) is used. These tests detect the disease, looking for traces of the genetic material of the virus in a sample more commonly through a nasal swab or throat collected. The Center for the Control and Prevention of Diseases (CDC) keeps the PCR the “gold standard” of COVID-19 control test, but, as all tests are not perfect. Studies have as much as 30% of COVID-19-PCR test results are proposed inaccurate. (By comparison, estimates of the CDC in 2018 that the rapid tests influence have about the same rate of false results.) With COVID-19 false-negative test results seem much more likely to be wrong to be positive, so if you have a positive result that will very likely get the virus have to do. If you get a negative result, but have no symptoms or corona occurred ill with the virus recently someone, you should always regress isolate themselves until symptoms. False negatives can occur if health professionals do not collect deep enough into the nose or throat a good sample. The timing of the test questions, too. Infections can lose if the test is done too soon after exposure shows, research. The opposite is also possible. “Sometimes, after the virus has been killed, there are still a lot of [genetic material] in the left body,” says Mehta. This can cause someone to test positive, even if they are not actively sick. First tested about five days after a potential exposure seems to be the sweet spot. a PCR-test phase and its results requires (known as reagents) special equipment and chemicals which are scarce, which is why such a test has taken stock, the US side is to read. To try to reduce the waiting time, several companies have put out original tests can detect the genetic material of a virus’ in a few minutes, but some, like the Abbott ID NOW tests at the White House used-have high rates of false negative results reported. These rapid tests are not readily available for most of the American public yet, but some experts say it could serve, despite their questionable accuracy an important purpose. rapid tests could significantly ramp capacity tests keep more cases of COVID-19 for the control of our test strategy in spite of the accuracy problems. Saliva Saliva testing Corona tests are a new type of PCR diagnosis for COVID-19 Saliva Test “standard PCR technology employees, and a bit ‘of manual labor that requires you to go through each step of the test,” says Mehta. But spit collection of do or least invasive of a nose or throat swab and easily at home without medical training, says Mehta. SalivaDirect, the Yale tests, also requires no chemical reagents or proprietary tubes that its developers hope will help ease supply and access. Early research conducted by Yale professional basketball players to test the saliva test is about as accurate as a conventional nose PCR test, but Mehta says, “We need more generally to test” to determine whether this statement is true. Antigen in the antigen test exam results in turn to minutes, but the speed is with compromises. As PCR tests require antigen test is usually a nasal swab or throat. But unlike PCR tests that look for genetic material from the virus SARS-CoV-2 antigen tests look for surface proteins on live virus. This process is a bit ‘less than PCR testing labor intensive, since it did not involve so much chemistry, but is also less sensitive. Mehta said that the door for possible false alarms opens (if the test takes up to proteins that look similar to SARS-CoV-2) (if completely lost protein) or negative. False positives are rare with antigen test, but at least half of the negative results are probably inaccurate. If you test negative, but they show symptoms or have risk exposure have, your doctor may have a PCR test to confirm the result. While the antigen tests are more common in the United States, a few such tests will have been previously approved by the FDA. Similar to a rapid genetic testing, some experts argue that fast-moving easily test antigen test bottlenecks could help enough to compensate for their reduced accuracy. antibody tests are listed in contrast with the other tests, antibody tests should not lead with SARS-CoV-2 current infection. Rather, they seek the blood for antibodies, proteins the body produces in response to infection that immunity can bid against the same disease in the future. These tests look for SARS-CoV-2-specific antibody to see if they have previously had a crown. At this time, the antibody test can not meet a lot of curiosity. First, says Mehta, are incorrect results quite often. Even if the results are accurate, scientists still do not know how well or how long someone antibody crown protects a future case COVID-19 A positive antibody tester does not mean that you do not COVID-19 back at least as far as can current science suggests. More extensive testing of antibodies for researchers because they can inform estimates of how many people actually had useful COVID-19 and help scientists learn more about whether and how the antibodies bestow Crown immunity. “From the scientific point of view there is a lot of information we can get from the antibody test, when we collect over time,” says Mehta. But in terms of useful information for individuals, antibody tests do not show much at this point. “Just because we are able to detect antibodies does not necessarily mean you are fully protected against the infection to acquire,” says Mehta. “Continue to take all the same precautions as everyone else.” Pictures
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