Things to note when testing corona virus fast

Dr. Truong Huu Khanh - Children's Hospital I said that the rapid test of corona virus aims to screen for early detection, but for people with negative results, they have not said anything.

Sharing on his personal facebook page, Dr. Truong Huu Khanh, Head of the Infectious Diseases Department, Pediatric Hospital I, analyzed: For those who get sick early, depending on the degree will have different results. When screening quickly by blood sampling to find antibodies, there will be 2-3 possibilities.

Hanoi is using a quick test to screen residents who have been to the "outbreak" of Bach Mai Hospital.

• The first possibility , being incubated but not enough time, cannot find antibodies because antibodies only appear when the virus has had to enter the body for a while, then the blood stimulates to produce. antibody.
• Second, only when the antibody concentration is large enough can the test detect it, and if it is too low, it cannot be detected.
• Third , when the antibody test results are positive, it is likely that they have had a long illness and have recovered for a long time or may cross with other non-new corona virus strains. For example, dengue antibodies may also cross with Japanese encephalitis antibodies because the two lines are the same.

'This quick test does not replace the strategies we may have done up to now, meaning that we still have to eliminate F1 and F2 subjects; Travel restrictions; wear masks; wear hats to cover drops in high-risk areas; limit close contact; Wash hands often with soap . ' , said Dr. Khanh.

Dr. Khanh said that it is necessary to have a very clear strategy, if the test results are negative, how do we advise people; If positive, then do something for people. We must have a long-term plan on this.

When people have positive results by rapid test, we need a quick answer from retesting by PCR . Individuals who test positive by rapid assay without PCR confirmation should not isolate them from those who are ill, requiring a separate area for these patients.

Dr. Khanh added that the new corona virus rapid test is now divided into two groups.The first group smears the nose and throat to look for the antigen in it (the corpse of the virus or the active virus) by PCR; The second group of people took blood to look for IgM antibodies , which appear in the early stage of infection (3-4 days after the onset of illness), and IgG is inherently increasing as the body responds first. corona virus (very long after appearing).

'I learned that the rapid test we are using is recording IgM / IgG, which means that searching together cannot classify IgM and IgG. Therefore, it is necessary to re-confirm the results by PCR to make an accurate confirmation soon, to avoid causing confusion to the people, '' Dr. Khanh emphasized.

Another important note that Dr. Khanh made is that people with a negative test result certificate by the rapid test method used to travel abroad, to be working, they need to be very careful. This is because there will be cases of false negatives .

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