What is The Difference Between RT-PCR And Rapid Antigen Test For COVID-19?

The new variant of coronavirus has affected millions of people in the world. It has different effects on different people. Many people who have the virus, have little to no symptoms and they do not require to be admitted to the hospital. But they can still infect many others. So, it becomes really essential to get yourself tested for the virus even if you have slight doubt of having the infection. In this way, you can save many other people by isolating yourself.

Considering the increasing number of coronavirus patients in the country, India needs to stand strong to the strategy “Test, Track and Treat.” There are different methods used for the testing of COVID-19. The most common methods used are – Rapid antigen test and RT-PCR test. People mostly get confused about which test to take in which situation. Here we will clear this confusion.^(1,3,6)

RT-PCR test is known to be the “gold standard” for detecting SARS-CoV-2. PCR test is done to detect RNA or genetic material specific to the virus. The virus can be detected within a few days of infection, even if a person doesn’t have any symptoms.

For RT-PCR, a throat or nasal swab sample is collected to do the test. The results came out on the same day or it can take 2-3 days also. But if the demand for the testing is higher, like in the current scenario, the results can take 7 days or more to come. This test is more accurate when compared to the rapid test.

The RT-PCR test is done for directly detecting the presence of the virus in the sample. It is helpful in the diagnosis of the active COVID-19 infection. In case the virus is there in the sample, the report will come as positive. The positive report is considered highly accurate after this test. On the other hand, if the report is negative, it is not necessary that you are not or cannot be corona positive. There are chances that the sample was taken in the early days when you didn’t have the virus.

So, in case you notice some symptoms after 2-3 days of the negative report, you are advised to take the RT-PCR test again to be assured of whether you have the infection or not.

An antigen test is often called a rapid test. This test identifies the protein fragments specific to the coronavirus. The results of this test come out really fast – in an hour or even less time. In some cases, the report comes within 15-20 minutes. A nasal or throat swab sample is taken for the test.

The positive report is highly accurate. The rapid test is known to be most accurate for people having COVID-19 symptoms. It may give faster results but the results may not be accurate always as it can miss identifying an active infection.

Now let us tell you about false reports i.e. false-positive and false-negative report:

A false-positive report means that a person does not have the virus but the report shows he/she is corona positive. The rate of false-positive report is really low. So, in case if you have taken a rapid test and it shows that you are suffering from coronavirus, it is more likely that you are actually corona positive.

A false-negative report means a person is corona positive and the report shows negative results. The rate of the false-negative report can be very high – as high as 50% – for people who have coronavirus but they don’t have any symptoms.

This is really dangerous as the person can spread the infection further thinking that he/she doesn’t have the virus but actually they are suffering from the disease. So it can be a hinder in checking the spread of the virus.

So, you are recommended to always follow the precautions even if your test report shows negative results.

Remember, this is our responsibility to contribute to the containment of this deadly virus.

If you have taken the rapid test and it showed negative results, but you have symptoms, then be aware. You are recommended to take an RT-PCR test.

It is highly recommended in case you have been exposed to high risk. If you had been in close contact with a person having coronavirus, for more than 15 minutes in the last 24 hours, and you were within the area of 6 feet from that person, it is considered high-risk exposure.^(2,3,5,7)

Although, we all know the guidelines to fight coronavirus, yet many people are avoiding these to a great extent. So, here are the basic precautions we need to take to cope up with coronavirus we all must follow:

• Always wear a mask and encourage others to do so.
• Maintain a distance of 6 feet from everyone even from your family members to the possible extent.
• Wash your hands for at least 20 seconds with a soap and water especially when you think you have touched something or someone having the virus.
• When soap and water are not available around, use a sanitiser having at least 60% of alcohol content.
• Don’t touch your face, mouth, nose and eyes with dirty or unwashed hands.
• If you feel sick, isolate yourself immediately so you don’t spread the virus to other people knowingly-unknowingly.
• Whenever you sneeze or cough, cover your mouth beforehand.
• Clean the surfaces and objects that are touched frequently.
• If anyone is sick around you, avoid close contact with him/her. But with this, provide that person with all the basic things as this is the time to support each other.^(1,4,5)

Getting yourself tested for covid-19 has become really important in light of the fast spread of the coronavirus. In case, you are confused about which test is correct for you, it is advised to consult a doctor or healthcare expert and take the test.

In any situation, you are always recommended to follow the guidelines. No matter what your report says, either you take a rapid test or RT-PCR test, either you get a false-positive report or false-negative report, either you are corona positive or not, always take the precautions until this pandemic ends. It is our moral duty to stand united in this toughest time.

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