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HealthResearch has shown that a person with a positive PCR test 10 days after symptoms has a small chance of being infectious

Research has shown that a person with a positive PCR test 10 days after symptoms has a small chance of being infectious

A well-known scientist of Montenegrin origin, Marija Backović, a doctor of biochemical sciences and molecular genetics, who has been working at the Pasteur Institute in Paris for 12 years, has been actively researching the new coronavirus for months.

Backovic answered questions about Covid-19, which were asked by readers of the “Antena M” portal:

“Dear fellow citizens of Montenegro,

the answers to the questions below are given on the basis of my personal, and limited, knowledge and research published up to July 30, 2020, in the best interpretation I could present to you. Sources of information are listed, and I can share them with readers who are interested but do not have access. Some articles are original scientific papers, some reviews of scientific knowledge have been published in journals in which journalists report citing sources of information and whom I trust. All of this is done so that you can learn more about the virus that caused the unusual situation we are in, and develop a critical view of information and misinformation regarding the pandemic.

I am a doctor of biochemistry and molecular genetics and I have been dealing with viruses for almost 20 years, but I do not practice medicine and I do not see patients, so I recommend that you consult with your doctors and use the information I provide as miles for dialogue and better understanding – said Backović to the readers.

How do you explain the situation that the person who was tested for the first time 30.06 / positive, then 21.07. finding positive, then 26.07. positive again, she felt the first symptoms on 26.06. all the time in self-isolation.

How is this possible and what is the recommendation of Ms. Backović for such a case, (I note the person had relatively mild symptoms that lasted 7-8 days)

To be able to answer this question, we first need to understand what the SARS-CoV-2 virus is made of and what the PCR test detects. See also the illustration below. Like all coronaviruses – SARS-CoV-2 – the virus that causes ‘covid’ disease, consists of genetic material that is wrapped in a single membrane. In that membrane is protein S (from ‘Spike’ in English, which means spike or nail – it is so named because it looks like that). In order for the virus to be infectious, it must be in a complete composition, so both the genetic material and the membrane with S protein must be present, because the virus enters our cells with the help of protein S. Genetic material alone cannot enter our cells, ie. it is not infectious.

Studies have shown that complete virus can be isolated from covid patients no later than 10 days after the onset of symptoms (except in the case of a person who already had a weakened immune system, and where the active virus could be isolated 20 days after onset of symptoms; it is the only such example and is not a realistic representation of what is happening in the majority of the population).

Although the active virus is present for up to 10 days after the onset of symptoms, its genetic material can remain present in our body for up to 3 months after infection. The PCR test detects the genetic material of the SARS-CoV-2 virus. In most cases, genetic material is detected up to 17 days after the onset of the disease, but in a number of cases, especially in the elderly and people with severe covid, genetic material may be present for up to 3 months after the onset of the disease. This phenomenon is possible because our body needs some time to ‘cleanse’ itself of all fragments of the virus, which can ‘pour’ (‘viral shedding’) from the cells of our body that are damaged by the primary infection and die as part of a normal immune response. and tissue regeneration.

In conclusion – research conducted so far shows that a person who has a positive PCR test for SARS-CoV-2, 10 days or later after the onset of symptoms, has a very small chance of being infectious, ie. to be able to infect others. Some health organizations such as the WHO have changed their advice because of this knowledge and no longer recommend a mandatory negative PCR test as a condition for breaking self-isolation.

I add that people infected with the SARS-CoV-2 virus have the greatest potential to infect others in the period of 2 days before the onset of symptoms and during the first week of illness. Because of these two days of infectivity, it is important to adhere to measures of distancing, wearing masks, and hygiene before symptoms appear.

Are you aware that diabetics very rarely have the flu? Why is it like that? Although I have seen statistics in several groups, as well as in conversation diabetics claim that almost since they have had the same disease they have not had the flu the same thing with the corona (over 200,000 members and none positive)? What is it about?

I am not aware of the fact that diabetics rarely have the flu. What is known and shown for covid is that diabetes, along with increased blood pressure and heart disease, is a major risk factor for the more severe form of covid that requires hospitalization; such patients have a poorer prognosis and are considered a high-risk group to which special attention should be paid in terms of prevention and treatment of covid.

It has also been shown that covid in some people functions as a trigger for diabetes because the virus can attack insulin-secreting pancreatic cells.

We have read various texts about the influence of coronavirus on the entire organism, what has been determined so far on which organs can be negatively affected?

The short answer is that the virus can affect the function of every organ, from the feet to the head. In some people, the infection is reflected e.g. only in the loss of sense of smell, while the clinical manifestation in others may include the collapse of the lungs, heart, and other vital organs. Why this is so is not yet clear, but a growing body of research indicates that the immune response, which varies from person to person, plays a role in which organs are affected and to what extent.

A more detailed answer is that the lungs are the primary organ that infects SARS-CoV-2. So far, it has been shown that the virus also reaches the digestive system, which is why gastrointestinal problems occur in some covid patients. The brain can also be affected; in addition, one of the first symptoms of covid may be loss of sense of smell and taste caused by damage to the tissue around the olfactory nerve (the nerve that transmits the odor signal). The infection can affect blood vessels and the heart, and uncontrolled blood clotting is often present in patients with a more serious form of covid, which is why they need higher doses of anticoagulants than are normally used. Appearances on the skin, so-called frozen toes, can occur due to changes in blood flow in small blood vessels that reach the skin.

Has there been data on the consequences it can leave and when a person is cured? What consequences can it leave on the lungs?

The long-term consequences of covid have been documented better and more detailed over time, and it is now clear that a number of patients experience symptoms such as fatigue, fever, muscle aches and weakness several months after suffering, and when neither the virus nor its genetic material of the virus can no longer be detected in their organisms. The hypothesis now being tested is that in these people the immune system, provoked by the SARS-CoV-2 virus, fails to return to normal and that this deregulation causes symptoms that last for a long time. So far it is not clear how they can be helped. In a certain number of patients, the infection can leave permanent damage to the lung tissue.

The wonder kids (teenagers) who are prone to allergies and have a very severe allergic reaction during the spring on the eye, the nose. (Pollen, grass, bee sting and axes …) as submitted to the coronavirus?

Do such children get sick more often than other children?

I can answer this question superficially based on a limited search of the literature. I recommend that you regularly consult with allergists who monitor your diet.

In short, the likelihood of children with allergies being infected with the virus is the same as for others, so typical measures to reduce the risk of exposure to the virus (distance, masks, hygiene) apply to such cases. For now, there is no evidence that the progression or course of the disease in children with allergies is different compared to children who do not have them.

Caution is recommended for people who have chronic or uncontrolled asthma because the lungs are one of the main organs attacked by the SARS-CoV-2 virus. In asthmatic patients, the probability of infection is the same as in others, but the development of the disease can be more complicated and recovery more difficult.

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