rapid test for coronavirus
The state of uncertainty is one of the most painful for a person. Having been under constant stress due to a global pandemic for almost two years now, waiting a couple of days for the results of a covid test can be a daunting task. Rapid tests will help to quickly determine the presence of an infection

Why rapid tests are needed

Experts believe that in addition to mass vaccination, rapid diagnostics to identify infected people and isolate them from healthy people will help stop the spread of coronavirus. Special express tests will help to cope with this task.

Express tests give an answer about the presence or absence of lgM and lgG antibodies, but not about their quantity. The detection of lgM antibodies may indicate a current infection (including those with asymptomatic course). The detection of lgG antibodies may indicate a past infection with a coronavirus / past illness and the presence of an immune response.

Accuracy of rapid tests is estimated at 80-90%, but speed is considered their main advantage. The result is ready, as a rule, in 15-20 minutes. Additional testing may be required to confirm for sure.

Anyone can make a rapid test at home or in the laboratory (as well as PCR analysis, a study to determine the level of antibodies) on a commercial basis¹.

Type of laboratory researchExpress analysis for antibodies
Detects antibodies to the infectious agent – immune cells that are produced in the human body as a result of its contact with the virus
MethodImmunochromatographic rapid test
Response formatКачественный
Type of biomaterialCapillary blood / blood from a vein
What will the test show?An antibody test measures the presence or absence of a person’s immune response to infection with the coronavirus.
The detection of early lgM antibodies may indicate a current infection (including those with asymptomatic course). Detection of late lgG antibodies may indicate a past infection with a coronavirus / past illness and the presence of an immune response
Detection of late lgG antibodies may indicate a past infection with a coronavirus / past illness and the presence of an immune response
Study appointmentsEstablishing the fact of past infection/disease
Study of herd immunity to SARS-CoV-2 coronavirus (lgG)
Features and limitationsAt present, it is not possible to say for sure whether antibodies provide protection against further infection and how long the immune response lasts.
Can be used in primary diagnosis to determine further examination tactics

What biomaterial is suitable for a rapid test for coronavirus

Blood

The most common rapid tests are those that use a few drops of blood to determine the presence or absence of a person’s immune response to contact with a virus.

Saliva

To detect the antigen of the SARS-CoV-2 virus, rapid tests are also used, in which saliva is used as a biological material.

Secret from the nasal cavity

A swab sample is taken from the nose. The result is ready within 15-30 minutes. Using the nasal rapid test, you can determine the COVID-19 antigen at home in the early stages of the disease.

Exhaled air

Testers that detect coronavirus in 45 seconds have just appeared in Finland. The Finnish company Deep Sensing Algorithms received a pan-European certificate for the world’s fastest tester2. It is enough for a person to exhale once – and the result is ready. It is not yet known how soon this ultra-fast tester will be available to the public.

Where are rapid tests for coronavirus made?

To date, dozens of test systems for the determination of the COVID-19 antigen by the express diagnostic method have been registered in the world:

  • Express tests made in South Korea are popular in Russia: NanoCare COVID-19 Ag, SD BIOSENSOR Inc, Biocredit COVID-19 Ag, SGTI-flex COVID-19 Ag, NowCheck COVID -19 Ag, etc.
  • Test systems from Chinese manufacturers are quite widespread: Leccurate Antigen Rapid Test, SARS-CoV-2 COVID-19 Ag Wesail, Hightop One Step Rapid Test, SARS-CoV-2 Xiamen Antigen Rapid Test, etc.
  • Russian-made tests approved by Roszdravnadzor – Rapid BIO, Imbian, etc.
  • Also on the market are tests from Italy, Belgium, Switzerland, the UK and other countries.

Any laboratory that has the appropriate licenses and is equipped with the necessary test systems can perform tests for coronavirus.

How does the coronavirus rapid test work?

Express tests for the determination of the antigen of the virus can detect it in the body from the first days of infection. They are analogous to a PCR test, but provide a result within 10-15 minutes.

A rapid test is an immunochromatographic method (ICA), which is based on the occurrence of a reaction between a virus antigen and its corresponding antibody in biological materials (blood, saliva). If the interaction has occurred, staining occurs on the chromatographic strip of the test system in the region of the control line.

Where to buy and how much does a rapid test for coronavirus cost?

Tests can be purchased at a pharmacy or online. However, experts recommend being examined only in a medical institution or a specialized laboratory, since they use tests approved by Roszdravnadzor, and the procedure is carried out correctly by experienced medical personnel.

The cost of an express test in a pharmacy is from 1900 rubles.

Can I take a rapid test at the airport or train station?

When crossing the border, you almost always need the result of not an express test (ICA), but a PCR (laboratory) result, certified by the seal of a medical institution and having a personal QR code. Therefore, we recommend that you find out in advance what medical documentation is required when entering a particular country, and take care of it in advance – undergo PCR testing and fill out the necessary questionnaires.

There are points for testing for COVID 19 at the airport and train stations. However, it is important to understand that the time for obtaining the results increases compared to the express analysis and can take up to 2-3 hours. It is recommended to take this into account when planning trips and travel.

Is it possible to do a rapid test for coronavirus at home

Can. But when performing rapid testing at home, it is important to understand that the reliability of the result can be reduced. As a rule, this is due to violations of the rules for collecting biomaterial.3.

Popular questions and answers

Answered questions related to coronavirus tests Deputy chief physician for medical affairs, obstetrician-gynecologist Yulia Sergacheva.

How accurate are modern tests for rapid research?

To date, the most popular tests have proven themselves quite well in practice. The analysis itself is based on the detection of a specific antigen of the virus. If you follow the rules for passing the analysis, its result can be trusted with a high degree of probability.

The manufacturers themselves claim an accuracy rate of 80% or more for express tests (as with a laboratory PCR test).

Can a rapid test show a false positive or false negative result?

Of course, the results of rapid testing should be interpreted by the doctor and serve as an addition to the patient’s complaints, the results of the history taking and epidemiological data (possible contacts with the sick, travel, etc.). Often they are used as a screening method and require observation of the patient and confirmation of the diagnosis with a laboratory test, especially in asymptomatic cases.

False-positive and false-negative results can be detected in any type of research – both in the express method and in laboratory tests (PCR, CLLA).

If we talk about a false negative result, then the reasons most often lie in the errors in taking the material or in violation of the preparation for analysis. There are strict pre-analytical requirements: refrain from eating and drinking for 3 hours before sampling, do not use drugs (antimicrobials, nasal and oropharyngeal sprays), do not brush teeth, do not chew gum and do not smoke. It is also advisable not to drink alcohol on the eve of the study.

In addition, test systems of inadequate quality, for example, expired, may be the reasons for a false negative analysis.

False-positive tests are less likely to be encountered, the main cause of which can be infectious diseases not associated with the causative agent of Covid-19.

It is important to understand that a positive result in an asymptomatic course is not a false indicator. Such patients are contagious to others!

In this case, we can confirm the reliability of the result by a study that determines the level of antibodies to COVID 19 in the blood serum.

Will rapid tests detect the Omicron strain?

The tests used in the Russian Federation are sensitive to the omicron strain. Many manufacturers of test systems write this in the annotations to their products: “They detect the Omicron strain. But, of course, so far not a single express test can distinguish omicron from, for example, a delta or another strain. But several manufacturers are working on such tests.

The launch of the production of express tests that detect Omicron in 15 minutes was announced by the White Service company of the FEZ Dubna.

A test system for the detection of “omicron” is being registered, created by the joint efforts of employees of the Institute of Chemical Biology and Fundamental Medicine of the Siberian Branch of the Russian Academy of Sciences, the Modern Laboratory Technologies company from Novosibirsk and the Department of Clinical Biochemistry and Laboratory Diagnostics of the Military Medical Academy. CM. Kirov. The result of research using such a test system can be obtained in 1 hour 25 minutes.

At the National Research Center of Epidemiology and microbiologists named after N.F. Gamaleya, they developed a test system for detecting virus-neutralizing antibodies to the omicron strain. But it is available only in the center so far. 

Is it possible to compare rapid tests and PCR testing?

Since the beginning of July, an experiment has been taking place in Moscow, during which the results of rapid tests and PCR tests were compared. Express testing showed 85% efficiency. Therefore, it was decided to introduce rapid testing for patients with symptoms of SARS. And in October, Muscovites got the opportunity to take a free express test (nose swab) for antigen to COVID-19 in several public service centers and shopping centers.

Sources:

  1. About the types of research for a new coronavirus infection COVID-19 https://www.rospotrebnadzor.ru/region/rss/rss.php?ELEMENT_ID=14612
  2. Press release “World’s fastest COVID-19 detection is here” https://dsa.fi
  3. INTERIM GUIDELINES FOR THE PREVENTION, DIAGNOSIS AND TREATMENT OF THE NEW CORONAVIRUS INFECTION (COVID-19) https://static-0.minzdrav.gov.ru/system/attachments/attaches/000/055/735/original/BMP_COVID-19.pdf
  4. Information about the new coronavirus infection for healthcare professionals. https://minzdrav.gov.ru/ministry/med_covid19
  5. Free express testing for COVID-19: answers to the main questions https://www.mos.ru/news/item/97350073/

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