In most countries, there has been virtually no marked change in mortality rates, some increase in mortality in the USA (from 5.1 to 5.86%), Germany (from 3.07 to 4.69%), Norway (from 1.31 to 2.8%), was statistically unreliable (OR: 0.833 (95% CI, 0.262-2.642), p=0.756; 0.600 (96% CI, 0.147-2.433), p=0.475; and 0.33 (95% CI, 0.35-3.150), p=0.337) respectively.
The persistence of a stable level of lethality in coronavirus disease seems to be due to the difficulties of etiopathogenetic treatment of this viral infection. The existing methods of medical treatment are extremely variable, the drugs used were mostly recommended by the principle of ”repositioning” drugs and imply the search for drugs for the treatment of a new disease among the substances already studied in clinical trials or used in clinical practice [9]. Almost to this day, there are no drugs whose effectiveness has been proven by the results of randomized controlled trials and meta-analyses. An example is the recent WHO recommendations not to use chloroquine/hydroxychloroquine that are not based on strong evidence in the treatment of coronavirus disease. 96,032 patients with COVID-19 from 20.12.2019 to 14.04.2020 were analyzed for the effectiveness of treatment in 671 hospitals on 6 continents [10].
10,698 (11.1%) of them died in hospitals, 14,888 patients formed 4 groups: within 48 hours after diagnosis, they began receiving chloroquine (1,868), chloroquine with macrolides (3,783), hydroxychloroquine (3,016) and hydroxychloroquine with macrolides (6,221 patients). 81,144 patients did not receive treatment for any of the schemes made up the control group. In the control group, the mortality rate was 9.3%, in the group receiving hydroxychloroquine - 18%, hydroxychloroquine with macrolides - 23.8%, chloroquine - 16.4%, and chloroquine with macrolides - 22.2%.
Scientists from South Korea have screened about 3,000 approved drugs and found substances potentially effective against SARS-CoV-2 and considered niclosamide and cyclosonide the most promising [9]. The genomes of SARS-CoV and SARS-CoV-2 viruses coincide by 79.5% , and therefore the authors suggested that drugs that suppress SARS-CoV may also be effective against SARS-CoV-2 [57].
Out of 3,000 molecules, 35 were identified that inhibit SARS-CoV-2. In the course of the experiment Vero cell culture (normal kidney cells of African green monkey) was treated with the drug, and then infected with SARS-CoV-2. 24 hours after the infection the immunofluorescent cell analysis was carried out with antibody that recognized SARS-CoV-2 nucleo-capsid protein - it was identified as the most significant 2 medications. Niklozamide, an antihelminthic drug used in tapeworm infestation, was very active against SARS-CoV-2 (IC50 semi-maximum inhibition concentration - 0.28 µM) and was effective against a wide range of viruses, including SARS-CoV and MERS-CoV. Ciclesonide, an inhaled corticosteroid, is used to treat bronchial asthma and allergic rhinitis, although its activity was significantly lower against SARS-CoV-2 (IC50 - 4.33 µM).
Possible reasons for the lack of reduction in mortality can be a gradual reduction in the resources of medical organizations, health care in general, the growing shortage of medical personnel due to their morbidity, mortality, physical, moral and psychological fatigue, lack of proper material and moral support.
In April, the unemployment rate in Sweden reached 7.9%, excluding seasonal factors - 8.2%. Bloomberg analyst Johanna Jeneson forecasts that unemployment will rise to 17%. Thus, the Swedish economy, which refused to impose a strict quarantine, did not help.
Analysts of the Financial Times, comparing the mortality during the pandemic in 13 countries in March-April 2020 with the average for the same period in 2015-2019, noted an increase of 49% in 2020: in France 34%, Italy 90%, the Netherlands 40%, Spain 51%, Belgium 60%, Sweden only 18%.
But according to countrymeters.info, in January-March 1,580 people per day died, in 2019 - 1,586 people per day. In USA in the first three months of 2020, 4,477 people died per day, and in 2019 - 7,458 people died per day. Spain - 1,098 and 1,105, Germany - 2,400 and 2,410, Russia - 5,538 people per day (including from COVID-19 - 450 people) in 2020 and 5,563 people per day in 2019.
The infection rate in the Russian Federation in the middle of March was at the level of 3, 15 May - 0.9, for a full economic life 0.5 is required. As of May 15, 2020 in 28 regions the coefficient was <1, in 9 - about 3.
Hospitalized on May 20, 2020 in Russia - 109 thousand people, 2,500 - in the ICU. By severity: heavy - 4.2%, medium - 34.9%, light - 60.9%. Of the specialized 165,290 beds, 110 thousand (66%) are used, 92% of the beds with ventilators are not occupied. Thus, 2.29% of patients with COVID-19 were hospitalized for intensive care and resuscitation. On the one hand, the high percentage of unused, especially expensive beds is a serious, additional burden on health care, which certainly contributes to growth, ”accumulation” of patients waiting for planned, especially surgical treatment. But on the other hand, the complexity and unpredictability of the epidemiological process, the emergence of new outbreaks, justifies the over-deployment of infectious beds, at least until the infection rate < 1.0, after the ”plateau” of morbidity has been completed and the decline began.
By 25 May 2020, 3,807 people had died from COVID-19 in Russia, which would have been about 14.64% of all deaths in 2019 in Russia due to pneumonia (26,000).
In 2019, the total mortality rate in the Russian Federation from all diseases was 1.2%, and from coronavirus during the pandemic period was 0.98-1.05%. Thus, in the structure of total lethality, deaths from coronavirus may be 0.21% (3,807 deaths from COVID-19 as of 26.05.2020 for a total of 1,800,000 deaths in 2019).
Concomitant diseases and infections lead to an increase in the severity of respiratory viral infections and mortality [11]. Most deaths during the 1918 influenza epidemic were caused by subsequent bacterial infection, especially Streptococcus pneumonia [11].
Poor outcomes of the 2009 H1N1 flu pandemic were also associated with subsequent bacterial infections [12].
In the current COVID-19 pandemic, 50% of patients who died had secondary bacterial infections [13], with both bacterial and fungal infections reported [14].
Patients with COVID-19 are on an invasive ventilator for a long time (on average, 9.1 days), which increases the likelihood of developing hospital- and ventilator-associated infections.
It is important to prevent the second wave of the epidemic, which is predicted by many virologists in autumn-winter 2020.
In Berlin, scientists suggest tightening the quarantine at 30 newly infected per week, then the extreme color of the epidemiological ”traffic light” turns on, at 20 per 100,000 - warning yellow. The second factor - the coefficient - is the so-called coronovirus reproduction index, i.e. the number of people infected by one infected person. Only when this coefficient is < 1.0 can the epidemic be kept under control. If for 3 days in a row 1 infected person will infect 1.1 healthy - the color of yellow is turned on, at a factor of 1.2 - red ”traffic light”, the third criterion - the number of beds for heavy patients with COVID-19 in the intensive care and intensive care units in the clinics. In the ”quiet period” 9% of the beds are occupied, if this indicator reaches 15% - yellow will light up, at 25% - red color of the epidemiological ”traffic light” (http://p.dw.com/p/3cAza).
With two yellow signals at 3 ”traffic lights”, the Berlin (Senate) management begins a thorough analysis of the situation, and with two red signals, it decides whether to introduce quarantine restrictions again, if yes, which ones.
Obviously, apart from these figures, it is important to monitor the dynamics of the epidemiological process.
German scientists have summed up the first results of the fight against COVID-19 in the country (DW-Breaking World News, 20.05.2020) and among the key factors to contain the coronavirus epidemic in Germany, they call the decisive actions of the authorities, on the one hand, and the loyalty of the population to the decisions of the authorities, on the other. Now, after the easing of restrictive measures, in places of mass appearance of people, such measures as thermometry in front of the entrance to shops, mandatory hand disinfection, issuing masks to all visitors and inside the building, social distance is maintained.
According to German scientists (prof. Karl Gustav Karus University hospital Michael Albrecht) the new coronavirus has nothing to do with ARVI or flu. COVID-19 in the worst case affects not only the lungs, but also other internal organs, causes severe immunological reactions in them, affects the central nervous system. Scientists believe that the widely discussed problem of lack of ventilators is just one aspect of the treatment of patients with COVID-19. Thanks to the cancellation of public events and the prohibition of human contact, the spread of infection in Germany was stopped (http://p.dw.com/p/3cAza).
Similar experiences in the fight against the pandemic in Austria, the Czech Republic, China, Russia have also shown the effectiveness of such restrictive measures (morbidity, mortality, etc.).
According to various virologists from England and Germany, the pandemic may last for another one to two years. It is believed that COVID-19, on the one hand, will not disappear, and on the other, will not become an obstacle to the normalization of life, which will occur due to vaccination or the acquisition of immunity by the population naturally [7].
According to computer simulations of the pandemic from Johns Hopkins University, which were developed under the condition that antiepidemic measures were maintained or introduced, quarantine measures could be withdrawn in most countries no earlier than August-September 2020.
The emergence of the experimental vaccine and its application to the vaccination of medical personnel is predicted in November 2020, and mass vaccination in spring 2021 [8].
One of the most common models for predicting the development of epidemics is SIR, which was developed in the late 1920s (an acronym formed from the first letters of the words ”susceptible”, ”infected” and ”recovered”) [15].
The essence of the SIR model is that the entire population is divided into the susceptible – those who may be infected, those who are actually infected and recovered.
Several variations of the models have been developed to date, including SEIR, where E means exposed, i.e. infected with the virus during the incubation period (contact). These people have already been infected, but the symptoms of the disease are not yet apparent. According to the SEIR model, susceptible people first become infected, then the incubation period lasts for some time, after which they develop symptoms and eventually recover or die. In the case of COVID-19, infected people can infect others before symptoms appear, which makes the virus particularly contagious (the incubation period of the coronavirus is on average 5-6 days) [16].
The infectivity (pathogenicity) of the virus is measured using the index (coefficient) of basic reproduction – RO, if it is equal to 1.0, then each person infects another person, and that person then passes the virus to another person, and so on.