The SARS-CoV-2 virus, which causes the COVID-19 virus infection, enters the human body through the mucous membranes of the nose, eyes or mouth, as well as other respiratory agents (microorganisms that cause diseases). In the first days after human infection, the coronavirus actively multiplies in the epithelium of the nasopharynx, and at this point carriers can spread it by sneezing, coughing, and even deep breathing. Therefore, in the fight against the spread of coronavirus, medical masks are effective.
Whether a person is infected or not can be determined using a PCR test. PCR is a method by which you can multiply a certain section of DNA so that computer equipment can determine the presence of viruses, fungi, bacteria and other types of foreign microbes in human biological materials. In this case, we are interested in viruses. You can read more about what PCR is here.
On the epithelium of the nasopharynx, the virus does not linger long, as it meets the response of the immune system. The infection is contained in the mucosal secretions and saliva.
Unfortunately, practice shows that the PCR test, tested for years on other infections, in the case of COVID-19 gives quite a lot of false negative results (this means that a person may be infected, but the test will show that he is healthy).
Due to the inaccuracy of the tests (many false negative results, which is dangerous misinformation), these tests are repeated several times to minimize the likelihood that an infected person will be given the “green light” to visit work, school or other public places. If the virus is not detected for a long time, but there is still a suspicion of it, then blood is given for antibodies to the infection.
Who might need a PCR test for coronavirus?
Which people should take the test?
- Who was in contact with a person who was subsequently found to have COVID-19
- Patients with pneumonia.
- Pensioners over 65 years of age with signs of ARI / ARVI
- Who visited regions with a high level of morbidity and found themselves with symptoms of ARI / ARVI after that
- Those who are at risk for health reasons (cancer patients and people with chronic pathologies)
- patients with covid-19-to confirm their recovery.
All of the above test should be carried out free of charge (under the MHI policy). Everyone else can take the test for a fee. For this purpose, research institutes that have a state license are suitable.
what do you need?
In order to reduce the risk of a false negative result, it is necessary to…
One day before the delivery of samples:
- Do not take antimicrobial drugs
- Do not drink alcoholic beverages.
2 hours before the delivery of samples:
- Don’t drink or eat.
- Do not brush your teeth, do not use refreshing lollipops, chewing gum, do not use oral products, inhalers, nasal preparations.
- No smoking.
That is, you need to leave alone the place where the smear is taken, as well as all places bordering it.
How is the test going?
for the patient, it’s very simple. He take a swab from the throat [the throat is the opening connecting the mouth with the pharynx and limited from above the soft palate, below — the back of the tongue and on the sides of the palatal handles between the tonsils]. a smear can be taken by a doctor or by the patient himself, if the diagnostic kit is delivered to his home by a courier of the medical center.
an applicator with a sterile swab at the end is carried out several times on the mucous membrane. Then the taken material is placed in a sealed bag and sent to the laboratory. after that, we can only wait for the results.
The waiting time for a standard test is from 2 to 5 days. the rapid test takes from 30 to 60 minutes, but has an even greater margin of error. The data of the express test can only be considered preliminary, they require mandatory verification.
there are two possible test results in total:
- “SARS-CoV-2 RNA not detected” – this means that the virus was not detected in the biological material received from the patient, that is, the test is negative.
- “SARS-CoV-2 RNA detected” – this means that a coronavirus has been detected in the patient’s body, that is, the test is positive.
If there are doubts about the reliability of the test results, then you can take it again – in 4-5 days.