Me many ask, what kind of mess we have going on with the tests Covid-19. Why so many false-negative results in the apparent symptoms, why have to wait long for the answer, when finally will appear a blood test for antibodies. I’ll try to answer briefly.
1. The main method of diagnosis Covid-19 for today — PCR, analyzed material obtained with the aid of the smear from the nose and oropharynx.
2. PCR is a very accurate molecular genetic analysis, but it is highly dependent on three things: the right fence material, compliance, transportation and quality of training samples in the laboratory.
3. A swab should be taken not earlier than 2 hours after eating and drinking, ideally in the morning on an empty stomach and that is not always observed.
4. Maznut a reindeer “somewhere in your nose” and casually “slip in the amygdala” means guaranteed to get false-negative result.
5. The analysis can be stored and delivered at room temperature.
6. The analysis should be completed within days, or frozen.
7. Dig the material into the dies should feldsher-laboratory with experience in PCR, undergone additional training to work with a specific infection. Failure at this stage jewelry can easily screw up the process.
I do not need to analyze in detail each item, lot, and so it is clear that today all the important features of collection of material for this accurate, but very capricious analysis, are not always respected. Is it possible to blame people? The number of analyses is growing like a snowball, laboratory work until late at night or around the clock and still struggling to cope with the flow.
Physically will do more tests than in the laboratory set of amplifiers, and even if you miraculously manage to purchase the devices again and again (and fails, despite the fact that foreign producers are not in a hurry to sell something that is in dire need), all inevitably comes down to lack of qualified staff. No country in the world was not ready for the amount of some specific tests for a couple of weeks will increase to 40 times!
The problem can be solved by a wide application of immunochemical rapid tests for antibodies. This analysis determines the presence of specific antibodies — immunoglobulins (IgM and IgG). Increase the level first talks about the acute phase of illness, the second — on the transferred earlier the disease. If you define those and others (like several of my colleagues from the Moscow hospitals) — means the acute phase of the disease is completed.
The stated accuracy of these tests is 92-93%, and the experience of use in hospitals have shown that they cannot confirm Covid-19 a large part of patients with clinically and radiologically typical coved-pneumonia, but a negative PCR result. Analysis quick and simple to perform (10 minutes vs about 4 hours for one cycle of PCR), and can be performed independently at home (if you’re not afraid to pierce my finger).
Now rapid tests are admitted to the hospitals of Moscow: they tested patients unclear and massively staff. The good news is, I personally know at least 10-15 cases when according to the test result of a person ill with the “Kovalam”, and can remember a couple of days sluggish subfebriliteta, weekly pokalyvanie or not notes any symptoms. I look forward to when they start to test us.
Today in Moscow, this analysis can be done only in one place in SKOLKOVO (Google to help), but I imagine there is a queue. Heard call and make simply unrealistic. Fortunately, today, several leading private laboratories has announced that it will begin doing these tests since the beginning of may, the cost analysis will vary from 2 to 4 thousand rubles.
Imagine how soar the number of new cases, and for many, the news of the illness will be a surprise. But the new data will be diluted and reduce the mortality rate, which is undoubtedly good. By the way, in many European countries, rapid tests for 2 weeks sold in pharmacies, I wonder if they planned pharmacy selling us.
Also soon will be available for quantitative analysis of antibodies (showing not just the presence and level of antibodies). It will be important for donors to recover from hyperimmune plasma and evaluation of the intensity of immunity.
Attach the infographic on the right fence smear for PCR. Today, many laboratories offer patients to take themselves strokes on their own, so that will probably come in handy.
Aleksey Fedorov, head of the operational Department of the Center for cardiovascular surgery of the hospital. Burdenko
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