Who and why do rapid tests for coronavirus

Measures against the virus are being phased out. Is the epidemic gone?

No. Perhaps we will even have a second wave.

The fact is that the coronavirus turned out to be unexpectedly unpredictable. The mathematical models on the basis of which scientists tried to understand how the epidemic would develop were not accurate enough. And the virus itself is not yet well understood so that we can tell how it will behave in the near future.

In Russia the situation is stabilizing, but in the world so far everything is different. According toWHO Coronavirus Disease (COVID-19) Dashboard WHO, in Europe, the epidemiological situation is slowly but improving. But in the Americas (both North and South), the number of cases is growing. Perhaps this is due to the fact that against the background of protests, people stopped observing quarantine. And it is possible that after the abolition of all restrictive measures in our country, the virus will intensifyThe WHO warned of the second wave of COVID-19 in Russia "even tomorrow".

Is it true that you can get sick and not notice it?

True. You can transfer the disease and not understand that it was a coronavirus. COVID-19 refers to respiratory diseases, which are those that affect the respiratory tract. But the peculiarity of the infection is that it is transferred in different ways. Someone will get off with a slight cough, someone will have a fever, and someone may end up in intensive care when artificial ventilation is required.

There are cases of asymptomatic carriage of the virus, there are quite a few of themAdvice on the use of masks in the context of COVID-19, but how much - no one knows. Since with this option, the carrier has no signs of the disease at all, even a cough, it can only be detected by testing for the virus, and not everyone does it.

Which test should you choose?

There are two options:

• PCR;
• rapid test for antibodies.

PCR - polymerase chain reaction - reveals the presence of a pathogen in the body. In the case of coronavirus, a swab from the nose and throat is taken and then the collected material is placed in special conditions. If there is an infectious agent in it, then after the reaction, the number of nucleic acid fragments in the sample will increase - the presence of a virus will become obvious. If there was no infection, then nothing "will grow" after PCR. This is a fairly accurate analysis that allows you to detect coronavirus infection in the early stages, but it has a drawback - it takes several days for the reaction to take place.

Rapid antibody tests do not detect the pathogen itself, but look at how the body reacted to the presence of an infection, if any. Such tests can be done faster than PCR, they are based on the method for determining antibodies to the virus.

The first registered express test, which has passed comparative studies in the hospitals of the capital, is Biozek Medical, produced by the Dutch company Inzek International Trading. From April 25, Moscow purchased and in the period until May 7 used about 180,000 of these rapid tests, including among hospital, polyclinic and ambulance staff. This made it possible to quickly identify asymptomatic cases and take the necessary measures in time.

How does the Biozek rapid coronavirus test work?

Each causative agent of the infection has a protein - an antigen. In response to the appearance of an infection, the body producesCOVID-19 Serology Testing Explained antibodies that are needed to fight the pathogen. They bind to the antigen to neutralize it.

Rapid tests work like this: a manufacturer applies a protein antigen to a strip in the laboratory. If you then drop blood on this strip, then by the reaction of the material on the strip you can understand whether there are antibodies in the blood or not.

First, IgM antibodies appear in the body (after 3-5 days from the moment of illness), then (after 10 or more days) - IgG antibodies. The test is sensitive to both types, that is, it can be effective 3-5 days after the onset of the disease.

Learn more about Rapid Test

Could it be that the test is wrong?

This is possible, because in any case, each organism reacts to the infection individually. Someone does not produce antibodies, someone does, but in insufficient quantities - the test may not respond to them. Also, in rare cases, there is a false positive result - when in fact the person was not sick, and the analysis turned out to be a "plus".

But the Biozek test has high accuracy. This was found out when they checked the results of express studies using the PCR method: those who had the test detected antibodies were made an additional analysis for the presence of the virus itself. As a result, high sensitivity and specificity of at least 92% are confirmed.DEEPZDRAV EXPLAINED THE APPLICATION OF EXPRESS TESTS Moscow Department of Health.

If the rapid coronavirus test is so easy, can I buy it and do it at home?

No. The instructions for use for the rapid tests indicate that they are for professional use only. medical professionals in clinical laboratory diagnostics and are an auxiliary tool in diagnostics COVID-19. Biotek, which is the official distributor of Biozek Medical in Russia, does not sell express tests to individuals and pharmacies and indicates on your website, which are primarily provided by these means:

• state medical institutions;
• medical centers;
• companies to test employees if there is evidence that the tests will be used by healthcare professionals.

If you decide that you want to get tested, it is better to contact a medical institution. Still, for the test, a blood sample is needed, and the health workers will do it correctly, which means that the probability of an error will be less.

Does everyone need a rapid coronavirus test?

Not really. If you are at home on self-isolationCoronavirus Disease (COVID-19): Frequently Asked Questions, do not contact with people, use little public transport, then continue to comply with restrictions, wear a mask and wash your hands often. You don't have to do the test.

But if you are forced to contact a lot with others or your company has decided to get out of the self-isolation mode, then it is worth checking. For example, medical professionals need tests. It is also worth getting tested if you are a salesman, taxi driver, commute to work by subway or bus.

• If the test is positive, then it must be confirmed by PCR. This is necessary to exclude false results and to understand: you are still sick or have already suffered an infection.
• If the test is negative, this does not mean that you will not get the virus tomorrow. But in any case, the analysis helps to understand how things are with your health and what to fear.

Biozek's express test showed that I have IgG antibodies, so I won't get sick again?

We do not have such data. It is not known if covid can be re-infected. In addition, chances are that it is your antibodies that will not be able to suppress the virus. This is rare, but it happens"Immunity passports" in the context of COVID-19. But in most cases, IgG antibodies show that you have already cleared the infection.