Under the heading “Let's Talk About Science”, “Military Review” tried to collect data from leading scientists and virological laboratories of the world, published over the past few days on the characteristics of a new type of coronavirus infection.
In the scientific journal "New Infectious Diseases" an international group of scientists from the USA, France and China published an article that tells about the calculated serial interval of the spread of the virus.
We are talking about the time that passes before the manifestation of the disease in two people with the coronavirus COVID-19 - in a person who infected himself and who became infected from him.
A group of scientists claims that for COVID-19, the serial interval was less than seven days - when researching in different countries. If we talk about statistics for China, then the interval is approximately 4 days.
From the publication:
The speed of a pandemic depends on two main factors: how many people each infected person infects and how long it takes for the infection to spread between people. The first value is called the playback indicator; the second is a sequential (serial) interval. The short burst interval of COVID-19 means that new flashes will grow rapidly and be difficult to stop.
Scientists noted that the serial interval for COVID-19 is significantly lower than, for example, for Ebola: 4-7 days versus several weeks.
Scientists report that research has revealed that every tenth case of transmission of a new coronavirus is from a person who has not yet felt any of his symptoms.
From the article:
Asymptomatic transmission makes pandemic containment significantly more difficult.
It is worth saying that the study was funded by the US National Institute of Health and the National Natural Science Foundation of China.
Another study talks about the stability parameters of the coronavirus COVID-19. The results of the study were published in the Medical Journal by scientists at Princeton University and the US National Institute of Health.
A study of COVID-19 showed that coronavirus is stable in air (in medical terminology - in a natural aerosol environment) and on surfaces from three hours to several days. The greatest retention time was recorded on plastic and, which was surprising, on stainless steel - more than 24 hours. But, for example, on a copper surface, the virus dies within 4 hours. It is argued that it is precisely the copper surfaces of SARS-CoV-2, so to speak, that it is “more afraid”. It is clear that the word “afraid” is more than arbitrary, since 4 hours for the virus is enough time to find a more suitable “carrier” for itself.
In a special laboratory, Rocky Mountain (USA) conducted a comparative analysis of two coronavirus infections: the current SARS-CoV-2 and its predecessor SARS-CoV-1. It turned out that the new coronavirus is significantly more tenacious.
Meanwhile, scientists Xi Licin, Tao Yi, Charles D. Cruz and Lokesh Sharma published an article that presented a study of cured patients. The material says that the average age of the studied cured was the age of about 35 years. A professor at the Yale School of Medicine, Lokesh Sharma, says that even after the symptoms of coronavirus infection completely disappeared, about half of the patients continued to be active carriers of coronavirus, which might not have manifested itself once or twice. Only two weeks later, the cured patients completely lost their ability to infect other people. That is why the mentioned experts advise to extend quarantine for an additional two weeks, even for those whose tests for coronavirus show a negative result.
Scientists Marion Parisis, Sylvia Behillill, Duke Nguyen and others presented data on the study of one of the first cases of new coronavirus in Europe. We are talking about patients at the clinics of Bordeaux and Paris (France). Patients are reportedly five Chinese citizens who came to France in mid-January. Their ages are from 30 to 80 years. It turned out that in an 80-year-old man, the so-called viral load was maximum (we are talking about the concentration of coronavirus in the tissues) of all five patients in French hospitals.
From the study:
An 80-year-old patient died on the 14th day of illness. Maximum viral load was determined in the upper and lower respiratory tract, as well as in plasma.
As it turned out, in women 30 and 46 years old, the main phase of the disease was asymptomatic. At the same time, viral RNA was detected by doctors in their feces. They eventually recovered, as did men aged 31 and 48. It is noteworthy that in men, tests showed the presence of coronavirus in smears from the nasopharynx.
Based on the study, which then spread to other patients, it was concluded that the diagnosis of COVID-19 can effectively detect the disease only with a comprehensive study: not only of the nasopharynx biomaterials, but also in the analysis of blood, urine and feces. In addition, scientists report three forms of the course of the disease: mild, severe and critical. However, the transition between them is still not fully understood.