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To this end, the University began to test the region’s population for the presence of immunity to COVID-19, said the scientist, “the Russian newspaper”.

Alexander, do I understand correctly, you do not mass testing and scientific research?

Alexander Botvinkin: Yes. Having accumulated enough material and analyzing it, we could give a more objective picture of the spread of infection and to adjust the strategy against the proliferation COVID-19.

Therefore, we do not aim to massively test the population of the region. We need to recruit a sufficient for scientific analysis of material using power swords Professors of the University and the results obtained in other clinics and laboratories of Irkutsk.

But you’re not blind lead the study? You probably already have a particular assumption that you intend to test?

Alexander Botvinkin: If perform official information about the number of infected people and the spread of COVID-19 in the region, we can see that the majority of cases not detected among the local population.

there were guests from neighboring countries or other regions of Russia. A vivid example of the labour migrants arriving to the construction of the Angara region. Why, then, there was a sharp increase in the number of those infected with the coronavirus among the local population, although surveyed tens of thousands of people? This result of preventive measures of isolation at the beginning of the epidemic? Or other measures that reduce the likelihood of transmission? Maybe a certain percentage of Siberians have already suffered the disease and have immunity?

it is Known that during the winter many people with symptoms of acute respiratory infection was discovered coronaviruses person that could change the susceptibility of the population to COVID-19.

so, you admit that the coronavirus could circulate on the territory of Baikal region in the past, even before the Declaration of a pandemic?

Alexander Botvinkin: why not? We can’t ignore the possibility. The argument can cite a historical fact. After the 1970-ies was opened, the human immunodeficiency virus (HIV), it was found that with the help of new laboratory tests it managed to detect in blood samples collected from humans much earlier. Perhaps this is not quite correct example, as HIV infection runs a chronic and is transmitted in other ways. But it demonstrates that science needs to test different versions, not just the obvious ones.

absolute Test detects the presence of antibodies to COVID-19?

Alexander Botvinkin: unfortunately, any test may give both false-positive and false-negative results. It is not excluded cross-reactions with related viruses, such as coronaviruses of man. But in General, enzyme-linked immunosorbent assay (ELISA) is considered quite specific and sensitive test. Quantitative estimates for test-systems for antibodies to the new coronavirus not yet available, as their widespread use is just beginning. However, it is known that antibodies produced in the body in response as the clinically expressed disease, and after asymptomatic course of infection.

at what point of the disease can be used to detect these antibodies?

Alexander Botvinkin: Antibodies of class M can be detected by the end of the first week after infection. It is the “first line of defense”, and they disappear pretty fast. In the future, begin to produce immunoglobulin G. They are detected in the blood with the end of the second week after disease.

the Number of antibodies reaches a peak on the second or third month after infection, and during this period, they are represented mainly by immunoglobulins of class G, which is stored in the body for up to a year or more. It is the presence in blood of immunoglobulin G indicates past infection.

Therefore, laboratories often used test system for the detection of immunoglobulin G. For COVID-19 such a test system developed by Novosibirsk scientific center of Virology and biotechnology “Vector”. And several similar test systems are licensed.

How is the fence material and, in fact, the analysis on antibodies?

Alexander Botvinkin: patient is taken blood from a vein. By centrifugation or another method separates serum, which is the material for the study. After collected sufficient to analyze the number of samples, they are delivered to a certified laboratory. For the study, using special devices – IFA-analyzers. The analysis itself takes several hours.

why do people get a response in a few days?

Alexander Botvinkin: While the answer to the patient about the presence or absence in its organism of antibodies to the virus COVID-19 do will be issued in four to five days. It takes time for testing the entire process chain. In the future, the timing of the receipt of the result, I hope, will be reduced.

Said in pharmacies should be here any test strips for antibodies COVID-19. Just a drop of blood from the finger can be used in the lab to seek.

Alexander Botvinkin: Yes, this is the so-called chromatographic tests, working on the principle of pregnancy tests. But their sensitivity is lower than the standard ELISA analysis. It is possible that they can appear in pharmacies.

But I don’t think it’s good when we are dealing with a contagious disease. It is necessary to take into account issues of biological safety and the need for coppermedical knowledge for correct interpretation of results. For example, antibodies can be detected for 10-14 days after infection, when the person is still contagious.

does the distribution of ELISA tests, their relatively low cost and quick result that in the future they will be used for the diagnosis of the disease?

Alexander Botvinkin: I Think not yet. For the diagnosis of the disease antibody test is not very suitable because antibodies can be determined after one to two weeks after onset of illness. With the help of test PCR (polymerase chain reaction) to identify the COVID-19 has the ability to detect the virus early. This test is more specific and sensitive. Although in China after the epidemic 2002-20003 years published articles about the feasibility of using parallel PCR and test for antibodies. In the long term for mass screening of the population can be developed ELISA test for the determination of not only antibodies, but the virus. But at this stage the main point of application of enzyme immunoassay is a retrospective assessment of the patterns of spread of the coronavirus among the population.

There are used mathematical methods, which allow you to predict the peaks, plateaus and valleys of the epidemic. Isn’t that enough? Need antibody tests?

Alexander Botvinkin: the Mathematical model on the basis of which was prepared forecasts basically assumed that the coronavirus is spreading in a fully susceptible to it population. And each person has an equal probability of infection and disease. But in the real world this is not always. It is well known that even during epidemics of the plague was sick, not all residents of the city or country.

Yes, according to reports from several European countries we see that the calculated growth curves and reducing the number of patients was confirmed. But there are other examples. For example, in our region, similar calculations, fortunately, did not materialize. After identifying the first cases, the number of cases in the month of April have increased much more slowly in comparison with the forecast. The increased incidence in may largely due to migration from other regions that the forecast was not taken into account. It is important to understand why it happened.

Today a lot of talk about the need for mass testing, including antibody COVID-19. What do you think?

Alexander Botvinkin: I Think mass testing is not necessary. For scientific conclusions rather selective survey of the population.

Practically, it is important to examine healthcare workers in the event of a positive result, they will not have to take a weekly PCR testing and will be much safer to work with Bo��a covered. Apparently, a survey of contact could reduce the burden on observation Department.

on the other hand, there are people who are interested in conducting such a study. Someone wants to chat with older relatives, knowing that you have been ill and not infect them. Someone is very uncomfortable to walk in masks and respirators, and some just tired to be afraid.

And the risk of re-infection exist?

Alexander Botvinkin: This risk, according to epidemiologists accumulated data is not completely excluded. Global distribution COVID-19 recent information, definitive conclusions are not enough. However, there is no doubt that the probability of recurrence for a person whose blood detected antibodies to the coronavirus, is very small, at least in the first year. In the future, the immune system may be weakened.

This is also true in relation to the immunity that is generated after vaccination. For example, vaccinated in childhood against measles, can develop in adulthood after exposure. Therefore, provided the revaccination and random testing of the population for antibodies to the measles virus. Similar problems will arise after you start vaccination of the population against coronavirus infection. Nevertheless, it is necessary to understand that vaccination is the only reliable method of preventing respiratory infections. But while the vaccine is in our possession is not.

And spread COVID-19 continues, and we have to endure limitations in public life. And, of course, has not been canceled sanitary rules that are already firmly entrenched in our lives: avoid confined spaces with a large crowd of people, observe social distance, don’t touch your face with your hands, wash your hands often. And stay healthy.

Tests that detect coronavirus, allow us to determine the presence of nucleic acids in humans. Biomaterial for analysis – swabs from the mouth and nasopharynx. This test is also performed before discharge of the patient from the hospital to check, cleared it from the virus or not. Repeat it two or three times. Antibody tests do not define the virus itself, and the presence of immunoglobulin, which is produced by the body to fight the pathogen. Biomaterial for him – blood. Rather, its serum.

All the materials of the story “COVID-19. We can do it!” read the .