I think the difference in immunity level may be the main factor. The persons with higher immunity level will resist infection, hence will suffer less from coronavirus infection, while persons with weak immunity level will suffer more from the infection.

According to my view, The COVID-19 Cases are Worse than Others, because of Its rapid spreading and more infectious character

The 'others' you talk about are different human beings at different physiological, economic, climatic and genetic states or levels. Don't you think that is enough for variability in intensities because I do.

Age is a significant determiner for COVID-19 virulence. A compromised immune system is another factor.

Based on my own reading of research published from China, where it started, Cornovirus has two stages of infection: Stage1 Respiratory that can lead to pneumonia in some cases, but mild cases and most of the cases are characterized by fever, coughing. Individuals that have a very reactive immune system may actually fare worse in the case of pneumonia, since the immune response is so extreme that appears to lead to lung damage in some. Stage 2: rare, but possible and continued infection into the brain stem and respiratory centres of the brain leading to further serious complications and death. This stage is associated with additional symptoms such as headache and nausea and vomiting. Does not look like anyone has deduced why the virus manages to progress to a neurological stage in some patients. Ages >70 is high risk and those with pre existing health issues. Children do not seem to contract the virus or may be carrier but most may remain asymptomatic. They can therefore be vectors of transmission.

Thank you Wilma Pretorius for your valuable input and discussion. Highly appreciated,

I also think that continuous exposure with poor immune system will put any individual at higher risk of debility than others with strong immune system despite applying precautions.

Recent studies identify that the virus infect the cell by the use of envelope-anchored spike protein that binds to the cell membrane and the binding site is activated by host cell enzyme furin. Furin is found in a lot of human tissues in the body. This means that virus has the potential to affect multiple organs. This is supported by liver failure observed in several cases. The difference in the individual response can be due to this reason.

Reference: https://www.nature.com/articles/d41586-020-00660-x

Logically speaking, the virus propagates better if it finds an optimal combination of its needed multiplication conditions (e.g. temperature, moisture, pH levels, proteins, micronutrients, lack of resource-competing infections), or a chance to adapt its host to its needs (e.g. anatomical, physiological, genetic modifications).

In a sense, it behaves like a parasite, but without the self-interest to necessarily kill its host.

The closer the "fit" with the propagation medium and the less resistance from it, the more effective the spread.

A first piece of scientific evidence that mild coronavirus infection in some people is due to human immune response. So, to keep a good immune system is very important. Published recently in Nature Medicine. Title: Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19.

"Researchers at the Peter Doherty Institute for Infection and Immunity in Australia have mapped immune responses in a patient in response to COVID-19 infection, demonstrating the body’s ability to fight the virus and recover from the infection. They suggest that immune parameters should be characterized in larger cohorts of people with COVID-19 with different disease severities, which might then help to predict disease outcome and evaluate new therapeutic drug or protective vaccine candidates."

Dear Colleagues and Friends from RG,

We now know that the overall pattern of the development of the Koronavirus epidemic causing Covid-19 disease in countries is similar. However, the pace of development of the Covid-19 Koronavirus epidemic in individual countries is not the same. This is determined by many factors. In addition to the issue of mutating the virus and creating new, other strains, varieties of this Coronavirus from current scientific research, we know that there are at least several other important determinants responsible for the unidentical development of the epidemic in individual countries or continents.

In my opinion, due to the high infectivity of Coronavirus causing Covid-19 disease, the threat of epidemic development is very high in every country where this virus appears. For example, compared to different variants of influenza, Covid-19 coronavirus causes a much higher level of infectivity and mortality. There is no confirmed data regarding the unambiguous, fully explained source of this virus. We do not know how long the pandemic will continue to develop in different countries and on a global scale. There is no vaccine or other effective treatment yet. However, differences in the development of a pandemic in individual countries are determined by many factors.

The most coronavirus infections causing Covid-19, the largest epidemic scale, the fastest growing Coronavirus epidemic is in those countries where:

1. The rules and recommendations for the necessary quarantine and isolation of individuals from each other are not observed.

2. There are more people suffering from various other diseases and chronic diseases, such as cancer, lung diseases, smoking-related diseases, coronary heart disease, and other diseases that reduce the efficiency of the body's immune system.

Many current scientific studies show that isolation is currently the best preventive solution because Coronavirus has a high level of infection and there is no vaccine or any other fully effective Coronavirus drug yet. In addition, it is estimated that many people who do not have disease symptoms, do not get sick, but they may already be infected with Coronavirus, so that the pandemic does not expand, all people should follow the recommendations, i.e. you should wash your hands often, stay at home and limit the exit from home to the necessary minimum. people who show any symptoms of a cold, such as a runny nose or cough, should not leave the house because they may be infected with Coronavirus, even though they are not seriously ill. The idea is to minimize the extent of the spread of the Coronavirus pandemic and currently isolation, home quarantine is the best solution for all people, regardless of whether they are sick or not.

Another important recommendation concerns the maintenance of high hygiene standards. Well, due to the development of the Covid-19 Coronavirus pandemic, it is recommended to wash your hands frequently with the use of detergents. Detergents damage the outer membranes of the Coronavirus structure and this causes the virus to disintegrate. In particular, remember to wash your hands when you leave and return home, and when being with other people. Most people who are infected with Coronavirus do not show symptoms of Covid-19 or only get the disease as if they were called common cold. Therefore, being with other people is not able to accurately determine the level of risk of infection with this coronavirus. Therefore, you should wash your hands often. It is also recommended to wash your hands after bringing home the various products purchased in stores. Of course, do not use too much detergents, too often, i.e. wash your hands with detergents every now and then or disinfect often with alcohol-containing disinfectants, because then the skin of your hands will be dried or allergic effects will appear.

Regards

Dariusz Prokopowicz

Thank you Dr. Yuan Yu for your scientific continuation. highly appreciated.

Virus load & continual exposure may be a factor as so many Drs & medical staff in Italy have gone down.