these and other questions of “Rossiyskaya Gazeta” meets academician of RAS, Professor, head of the Department of epidemiology and evidence-based medicine sechenovskiy University, chief epidemiologist, Ministry of health of Russia Nikolay Briko.
there is No consensus, when will the peak incidence COVID-19 and it will decline. Why is this happening?
Nikolai Briko: Indeed, there are different grades. They mainly relate to the timing of the onset of the peak incidence and the passage of the stabilization period of the high incidence of. Unfortunately, we know very little about viruses, and they are the most numerous representatives of life on earth. The number of viruses in trillions of times greater than the number of all plants and animals combined. To date, the world is open only slightly more than two thousand kinds of viruses. This includes viruses of vertebrates, plants, invertebrates, bacteria, fungi, archaea, and viruses to algae and protozoa. For people are a danger 25 families and 87 genera of viruses that contain thousands of types and subtypes. And the number of individual virus particles of each species, type, subtype or strain of virus can not be any account. And when there is a new kind takes a lot of time to study it and to understand the mechanism of its occurrence.
the Epidemiological situation of the country is heterogeneous. You can say that in Moscow it reached 3-4 phase I (according to who criteria), ie large-scale distribution without a follow-up epidemiological link of the cases. It is possible that a close fracture of the epidemiological situation that has developed in recent years. At least, the increase of new cases has decreased over the last month is more than three times and is 7-8 percent daily. But when the number of new cases will be 1 percent or even less a day, then you can definitely made to say that the situation is controlled. I think that after 12 may will be able to more specifically say at which phase of the epidemic process we are. But this is assuming that all we can until the end of the holidays to sustain the social spacing and isolation.
Why in Moscow, most of cases is detected? Because of population density? Or due to the fact that people are less disciplined?
Nikolai Briko: due to many factors. And because of population density. Due to the fact that the capital converge all traffic flows and is traditionally the most visitors. One of the measures after normalization of the situation in the economy should be a redistribution of aviapassazhirskie with the creation of several hubs in the country. In addition, traditionally, the possibility of transmission of infections with the aerosol mechanism of transmission is higher in large cities. This infection is characteristic��will suitsa a plurality of transmission paths. Leading by transmitting SARS-CoV-2 is airborne, which is implemented by coughing, sneezing and talking into close (less than 2 meters) distance. In addition to the airborne pathogen can spread and inhalation of dust and contact ways. Contact transmission path is carried out during handshakes and other types of direct contact with an infected person and through food, surfaces and objects contaminated with the virus.
the Virus has a certain resistance in the external environment and, consequently, can be transmitted via objects contaminated with the pathogen (door handles, the screens of smartphones, various household items, etc.), possibly through water and food. It is known that at room temperature for SARS-CoV-2 is able to maintain viability in different environmental objects for 3 days. The risk of transmitting the virus from the hands to the mucous membranes of the eyes, nasal and oral cavity proven. Equally important is the number of tests for the virus, which in Moscow is more than 40 thousand a day. Extension testing allows you to identify more asymptomatic carriers of the infection and the time to isolate them.
the Borders are closed for a long time. Whence come new patients?
Nikolai Briko: the Russian quarantine measures began to be taken at the beginning of January, when a group of diseases in China. At first they dealt with the restrictions on the border with China, transport links. Then they measure the development of the epidemic has become more diverse, increased and was of a public character. It is possible to significantly reduce the rate of the epidemic, buying time for mobilization of the medical service, to ensure its readiness to provide full and effective medical care to critically ill patients.
the time taken quarantine measures led to the fact that from China we have virtually no importation of infection. Most infected came to us from European countries. However still stuck back abroad, tourists and decided to return Home compatriots. According to the mayor of Moscow Sergey Sobyanin, over the last eighteen months in Russia came from abroad more than a million people, of which about 120 thousand Muscovites, almost half are “passed through Moscow and went on to the region.” “Can you imagine how many points, where we have citizens who have been there, infected some of them and came here. From the United States, from South-East Asia – that is, generally around the perimeter, from all over the world,” – said the mayor.
And this infection is insidious by the fact that she has a very long incubation period – from 2 to 20 days, and part of p��yehaveh sick after some time back. Today, the spread of the infection is already inside the country, inside of cities. And if the first task was to prevent the importation and to identify patients among coming now to identify all infected we can’t. Because now another phase of development of epidemic process – there is local spread of secondary and tertiary cases, which tells about multiple established sources of infection.
the Spread of infection is most active when close contacts in the family, in places of the big congestion of people, organized groups. As in all countries of the world, in recent years a growing number of drifts and the spread of infection in medical institutions and organized groups with a long stay of people (military groups, educational institutions, nursing homes, psycho-neurological dispensaries, penitentiary institutions, etc.). In these institutions, the issues of ensuring of epidemiological safety is especially important. The work of health workers is associated with very high risk of infection COVID-19, so important are the issues of security of personnel (skills donning and removing personal protective equipment, emergency personal prevention, etc.).
how many people suffer illness as they say, legs? The pill home and not even declare their status. Are there any estimates?
Nikolai Briko: At the moment the number of asymptomatic carriers of the coronavirus in Russia is estimated at approximately 45-50% of all infected. And in Moscow, their share is 60%. According to who, in the world today was mild forms COVID-19 in 80% of patients, medium – 15% of patients and severe in 5% of patients. In the course of the disease in mild or asymptotes form only laboratory tests can confirm the etiology and identify the infection.
Many people carry the infection home and do not go to doctors, no such data. But these people need to realize how much danger they pose to others, especially for the elderly and persons with chronic somatic diseases. Treatment of patients with mild forms of the disease (SARS, with only the defeat of the upper respiratory tract), asymptomatic forms of the disease typically is carried out at home under the supervision of trained physicians, General practitioners and other professionals or specially organized Observatory (hotels, country guest houses, sanatoriums, rest homes) under the supervision of trained doctors of these institutions. The results of screening the real number of cases COVID-19 to Moscow is about two percent of the population gcities.
the principle On which the virus chooses a “victim”? And why do some carry the virus have mild or even not notice it, while others end up in the ICU on a ventilator? There is even a view that the virus has mutated a long time. And those who have the disease is especially hard, picked up the heaviest strain.
Nikolai Briko: the outcome of the meeting with the agent and a form of manifestation of the infectious process is determined, on the one hand, the number trapped in the body of the pathogen (infectious dose), and on the other individual characteristics of the organism, the ability to resist infection. But there are also important genetics (genetically determined immune response), the presence of concomitant chronic diseases and timely treatment for medical help. Pathology cardiovascular, pulmonary and endocrine systems occurs in the elderly and in young people. And after 65 years for the majority of the population has two to three chronic diseases.
the Probability of death for patients younger than 40 years is about 0.2 per cent for patients older than 60 years, reaching 3.6% and for those older than 80, almost 15%. The timeliness of medical care also plays a role. Analysis of deaths shows that in most cases people are too late to seek help. At the stage of severe pneumonia, when the lungs cease to perform its function of oxygen saturation.
At what point we need to turn to doctors? In many ways, the symptoms COVID-19 because similar to the common cold.
Nikolai Briko: Yes, the clinical picture COVID-19 diverse and often similar to the manifestations of other viral respiratory infections. For all forms you need to seek medical help. Especially if the person had contact with SARS patients were in crowded places where they could become infected COVID-19. The mortality rate in COVID-19 is approximately three times lower (3-4%) than SARS (9.6 to 11%), and 10-15 times lower than in infections caused by MERS-CoV. It is obvious may indicate a lower virulence of the virus SARS-CoV-2 in comparison with “our elder brothers.” However, the rate of reproduction (number of new infections – R0) is at COVID-19 an average of 2.5. This is higher than seasonal flu (R0-1,5), but much less than for measles (R0 – 12), and varicella (R0-5). This infection will definitely occupy a special place in the group SARS, in connection with the special properties of the virus.
Now doctors have come to believe that COVID-19 affects not only the lungs, but other organs – the brain, heart, blood vessels. It turns out that everything is more than serious.
Nikolai Briko: Yes, it is. Polaroplast of the pathogen, the diversity of ways of infection determines the polymorphism of clinical manifestations ��of Peccei (acute respiratory distress syndrome, sepsis, septic toxic shock, multiple organ failure, etc.). Receptors ACE2, which most often is attached to the pathogen presented on cells of the respiratory tract, kidney, esophagus, bladder, ileum, heart, Central nervous system. Therefore can be affected any organs and systems of man. Among hospitalized patients, more than 90% have pneumonia, DIC – more than 50%, acute kidney injury is about 15% and myocardial damage more than 20%.
risk Groups are not only persons with chronic diseases and the elderly. Recent evidence suggests that high risk groups should include patients with proinflammatory and/or prothrombotic status. Individuals with autoimmune and rheumatic diseases, often accompanied by as violations of immunokompetentne and proinflammatory status and, often, activation of the hemostatic system are also at risk. Metabolic syndrome, obesity also play a negative role . Adipose tissue is a source of proinflammatory cytokines, plasminogen activator inhibitor type 1 (PAI-1) (contributes to the suppression of fibrinolysis, which increases the risk of mikrofinansirovaniya vessels of the microcirculation). Cancer – the risk of developing venous thromboembolism, particularly at risk receives hormonal and/or chemotherapy.
do You also think that the virus came to us forever and will eventually turn into a normal seasonal virus?
Nikolai Briko: Yes, I think so. Apparently, the epidemic COVID-19 today went down in history as an emergency situation of international importance. SARS-CoV-2 will enter into our lives, as did “swine” flu H1N1 in 2009, and will be one of etiological agent of SARS, showed their seasonal activity in autumn-winter and spring periods of the year. Perhaps with time it will reduce their destructive activity will become widespread by the fifth coronavirus, which we have to exist.
And the second, the third wave of the pandemic is possible?
Nikolai Briko: the Annual incidence of SARS really is characterized by the presence of two waves: fall – winter (October-February) and less severe spring (March-April). With regard to the incidence of COVID-19, now hard to say anything, largely this will be determined by properties of the pathogen, the severity of the mutation. While maintaining the antigenic stability of SARS-CoV-2 we can definitely say that a second wave of illness will be less severe because of the formation of population immunity. But to predict the situation is difficult because the virus is new, poorly understood and we don’t know.
the Virus is natural or if it is still created in a test tube? What is your opinion?
Nikolai Briko: Indeed, there are several conspiracy theories of the origin of the virus relating to the artificial or natural occurrence in nature. Most researchers favour the second theory and believe that the coronavirus SARS-CoV-2 presumably is a recombinant virus coronavirus between bats and unknown origin, coronavirus. Genetic sequence of SARS-CoV-2 is similar to the sequence of SARS-CoV1 at least 86%. The natural reservoir of the virus are bats. They are, incidentally, not hurting yourself, keep in nature the viruses of many severe infections (Ebola, Nipah, and coronaviruses). But the intermediate hosts of coronaviruses from different. In the case of SARS (atypical pneumonia) – it was small mammals (Himalayan civets, badgers, raccoon dogs, etc.). For the causative agent of MERS (middle East respiratory syndrome) – the one-humped camels (dromedaries). In our case, it is believed to be small mammals anteaters – pangolins (a genomic sequence is 99% identical to the genome of the coronavirus).
the Transition of the pathogen from animal to human, adaptation to a new ecological niche, the acquisition of the capacity for the subsequent transfer to the human population in some cases is fairly quickly and always carries a huge risk of epidemics.
Many of your colleagues tend to believe that the vaccine COVID-19 did not invent. Because of SARS, also a coronavirus, the vaccine could not create. SARS was lost in space.
Nikolai Briko: Yes, COVID-19 is the third coming of coronavirus with a high mortality rate. SARS disappeared, in fact. 16 years have no cases of detection of its pathogen. At the same time, the virus middle East respiratory syndrome continues to circulate, sporadic cases in humans are identified periodically. Mainly in Saudi Arabia.
Today we know at least two variants of the virus COVID-19, but genetically they are approximately homogeneous. Scientists from Taiwan and Australia reported the discovery of the first major mutations of the novel coronavirus SARS-CoV-2. But it is concluded that, in General, the genome of this virus is much more stable and less prone to mutations than the virus, “his older brother” SARS CoV. It is also more stable than other viruses that cause SARS. According to the authors, it is encouraging that the vaccine COVID-19 will be effective, though, if mutations of the novel coronavirus will continue, it may significantly complicate the work on a vaccine.
According to the current list of candidate vaccines against COVID-19, formed who, on 23 April 2020 in the world there are 83 drug, of which 77 are in preclinical studies, and 6 are clinical studies on humans. Nine Russian development of vaccines against COVID-19 included the world health organization in the list of promising. Among them, six products created in State research center of Virology and biotechnology “Vector” and three vaccines other research organizations. Federal medical-biological Agency of Russia announced the creation of three prototypes of the vaccine, which is a “recombinant proteins on the basis of surface epitopes in the S protein of SARS-CoV-2”. The results of the pilot studies expected in June, the second phase is scheduled for completion by the third quarter of the year.
the Creation of effective and safe vaccines will allow you to control this extremely volatile and dangerous infection with multiple active ongoing transmission of the causative agent.
