mutation?

The transmission of infection from asymptomatic patients is the most important feature of the new virus

It has become known to many that the morphological form of the Coronavirus is a shape that resembles a crown or a solar crown when imaging with an electron microscope, and that it primarily affects the respiratory system And the upper digestive system of mammals and birds. Although most members of the Coronavirus family only cause influenza-like symptoms during infection, the two viruses "SARS" and "MERS" (MERS - CoV) were able to infect the upper and lower respiratory tracts and cause severe respiratory diseases and other complications in Humans.

What about “Covid-19” (Covid-19), the new virus that causes symptoms similar to “SARS” and “MERS”, as people infected with these coronaviruses suffer from an acute inflammatory response (reaction)?

Dr. Elham Talaat Kattan, professor of pathogenic and molecular viruses at Taibah University, Vice Dean for Educational Affairs at Rayyan National Colleges in Madinah, spoke to "Your Health", confirming that there is no approved vaccine or anti-treatment for this virus so far, and that we need to understand the cycle of multiplication of the "Covid-19" virus, including This includes its source, how it is transmitted and how it is repeated, in order to find a treatment and prevent its spread.

As for the reason for the name and its origin, the name "Covid-19" (Covid-19) is derived as follows: "CO", the first two letters of the word Corona, "CORONA", and "VI", the first two letters of the word "virus", and "D" A letter from the word "disease" in English, "Disease", and "19" for the year of the outbreak of the disease 2019, according to the report published by the United Nations'' UNICEF.

Of animal origin

Dr. Kattan says that the classification of "SARS" and "MERS" as two viral diseases of animal origin, means that the first patients who contracted them got them from direct contact with animals. Although viruses have privacy in their pathogen families, their mutation is possible because the virus acquired a series of genetic mutations during its presence in the animal host and transmitted it, which allowed it to infect and reproduce within humans, and other things, it became possible for it to be transmitted from person to person. Field studies have revealed that the original source or what is known metaphorically as the primary intermediate host of "SARS" and Corona virus, and in general, is bats.

By tracking the epidemic of the virus, specifically when the outbreak of the Corona virus (Covid-19), the reports indicated that the first group of patients who received treatment in the hospital were workers or customers in the local seafood wholesale market that also sells processed meat and live animals, including poultry, Donkeys, sheep, pigs, camels, foxes, badgers, bamboo rats, hedgehogs and reptiles. Corona has not been reported to infect aquatic animals.

As a hypothesis, we ask a question: Is it possible that the Corona virus (Covid-19) may have originated from other animals sold in this market? Dr. Elham Kattan refuted that the hypothesis that the spread of "Covid-19", or rather its jump from an animal in that market, was strongly supported by a new scientific publication in the Journal of "Medical Virology", where scientists conducted a molecular analysis and compared the genetic sequences of "Covid-19". »And all other known corona viruses.

The study revealed that the genetic codes for "Covid-19" collect or are closely related to two samples of the SARS-like coronavirus from China, which initially indicates that, like "SARS" and "MERS", bats may be the source of infection as well and the first intermediate host. For "Covid-19".

The researchers also found that the sequence and coding of RNA to encode the protein of the "Covid-19" virus, which forms the virus particle that recognizes the receptors in a host cell, indicates that the virus in bats may have mutated before infecting people! But when the researchers conducted a more detailed bioinformatics analysis of the "Covid-19" sequence, it was found that the primary intermediate host may be snakes!

Bats and snakes

The researchers used an analysis of the protein codes preferred by the new Corona virus and compared them to the protein codes from Coronaviruses found in different animal hosts, such as birds, snakes, hedgehogs, bats and humans. Surprisingly, they found that the protein codes in "Covid-19" are very similar to those found in snakes.

Reports indicate that snakes were sold in the local seafood market in Wuhan, which increased the possibility that it himself had jumped from the host species (bats) to snakes and then to humans, coincidentally with the beginning of its outbreak in Wuhan. Factors contributing to the spread of infection were increased by a strong factor, such as low temperature, low level of hygiene and lack of health education. However, how the virus could adapt to both primary intermediate hosts of cold and warm blood remains a mystery! Is it latent within these families or a pathogen as well? A question that needs another hypothesis to prove it.

Since the outbreak of the disease, the seafood market has been disinfected and closed, making it difficult to track the first intermediate host animal that exported the "Covid-19" virus, and prevented viral RNA samples from being taken from all animals sold and sold in Market and from wild snakes and bats to confirm the origin of the virus. However, the reported findings also provide insights for the development of prevention and treatment protocols that we will cite and which all media outlets have publicized and taken care of.

Injury and symptoms

Virus link and access. They are the first two steps in the life cycle of the virus, as the initial attachment of the virus to the host cell through interactions between the protein "S" (S) and its receptors. The interaction of protein and “S” receptors indicates that it is the main determinant of corona virus in general, for infection and movement between host species and hosts.

After binding the receptors, the virus must obtain the host cell, as this is accomplished by the division and proliferation of the acid-dependent “S” protein, followed by the fusion of viral and cellular membranes, and this leads to the fusion of the viral genome and its eventual release into the cytoplasm.

Replication. The next step in the life cycle of the coronavirus is to translate the replication gene from RNA, and this is where both an active and an ed mutation lies.

Symptoms Both “MERS-CoV” and “SARS-CoV” are known to cause severe disease in people, while the clinical situation with respect to the virus “Covid-19” (COVID-19) is known. Still not fully understood, this also remains a mystery! The diseases reported ranged from mild to severe, including disease that resulted in death.

Common symptoms of human coronaviruses are: runny nose, sore throat, headache, fever, cough, and a general feeling of being unwell. Human coronaviruses can sometimes cause lower respiratory diseases, such as pneumonia or bronchitis. This is more common in people with heart and lung disease, people with weakened immune systems, infants and the elderly.

Infection

The index of sufficiency in cases of "Covid-19". Research conducted in this regard revealed that every infected person may transmit the disease to between 1.4 and 2.5 people, and approximately the ratio of the transmission criterion is from 1 to 3, which is the basic reproduction calculation of the virus, and bypassing the number 1 the virus is described as having "sufficiency." », And therefore it is not a virus that may end and disappear into the host on its own! This is an implicit mystery if it is permissible for us to be this way, for the measures taken by China and other countries in which the virus appeared, such as closing the cities in which the virus appeared, are the only ones that can limit its spread and lethality. The epidemiological figures for infections in their preliminary estimates indicate that "Covid-19" is placed in the category of deadly viruses such as "SARS".

When is the infection transmitted from the infected person? Dr. Elham Kattan says that Chinese scientists have estimated that those with confirmed infection with "Covid-19" can transmit the infection even before they develop symptoms. This is also a mystery! The time between actual infection and the onset of symptoms, known as the incubation period for the virus, is estimated to be between 1 and 14 days.

As for "SARS" and "Ebola", they are two viruses that are not transmitted until after symptoms appear, making it easier to deal with the spread of infection with them simply, and with simple procedures represented in discovering the infection, then isolating the infected and following up with whom they were contacting. While "Covid-19" lacks this property, which increases the complexity and response, and influenza is a common example of viruses that transmit its infection even before the patient realizes that he is sick.

In an interview with researcher Wendy Barclay, of the Infectious Diseases Department of Royal College of London, she said that it is easy for a chest infection to spread before a patient has symptoms. She added: "The virus can transmit through the air during normal breathing and speak to the person to whom the infection is transmitted." And she continued: "It is no wonder that the Corona virus is transmitted in the same way."

Nevertheless, we cannot say or completely assert that we have reached the stage where we are likely to turn the new virus into a global pandemic such as swine flu. The problem is that the person spreads the infection before he shows symptoms of infection, and this is what makes the task of the authorities concerned with combating the virus very difficult, but not impossible.

The other mystery that we do not know the answer to at all at the present time is how many cases infected with the virus are still in the incubation period and without symptoms!

The rapid spread of the virus. At first glance, it seems that the speed of the virus spread is very high when looking at the jump in the number of infected people from 40 infected to 2000 infected in one week, but the calculation in this way may be misleading. This large number of cases appeared due to the authorities ’improvement in their ability to detect infected cases, but sadly, there is not enough information on the" growth rate "and spread of the virus, while experts believe that the number of actual infected people may exceed to a large extent the number of cases that have been reported. about her. This is a mystery as well.

The Medical Research Center for International Analysis of Infectious Diseases at the Royal College of London said: “It appears that the spread of the newly discovered virus in Wuhan has caused minor or serious chest diseases to an extent that exceeds the number of cases reported so far.

Ways of spreading the virus. Usually, the common human corona viruses, which have become "Covid-19", are spread from an infected person to another by:

Coughing and sneezing.

Close personal contact, such as touching or shaking hands.

Touching an object or surface with the virus on it, then touching the mouth, nose, or eyes before washing hands.

People are usually infected with the common human coronaviruses in the fall and winter, but infection is possible at any time of the year. Young children are more likely to become infected, and people can develop multiple infections in their lifetime.

vulnerable groups It is the health-care workers who care for patients with "Covid-19" who are most at risk of infection People who come in close contact with the infected Travelers returning from locations affected by the spread of the virus, schools, childcare centers, workplaces and other places of mass gathering