Several years ago, while speaking at a security conference in Munich, Bill Gates said (1) that the world - apparently not at first sight - is not yet ready for a pandemic of a degree of seriousness, and the well-known American billionaire added that the countries of the world should It spends on scientific research on this scope as it spends on the arms industry, otherwise a pandemic could easily kill thirty million people in just one year.
A new world of corona!
With the emergence of the "new corona" last December, no one really expected that the number (2) of the 76,000 cases would have exceeded with more than 2,000 deaths, while we were talking, although death rates are few, compared to previous comrades of the same virus, such as respiratory syndrome. SARS and the Corona virus associated with Middle East Respiratory Syndrome (MERS), but its wide prevalence rates, lead us to question the future of Corona with our entire planet, especially China. Will it continue in the future? Will he stay with us? Will he, at least, continue to the next summer?
In fact, someone - unlike what you can see pervasive on the media - does not have enough information indicating that the virus will stop permanently next summer. This type of virus is likely to end by summer in the Northern Hemisphere, But (3) if we look a little further, we find that the Corona virus associated with Middle East Respiratory Syndrome (MERS) infected the Saudis in August, while the temperature was at its maximum.
Therefore, it is also expected that the new Corona will continue next summer, with low levels of prevalence, and with lower temperatures in the Southern Hemisphere, which opens the door to greater opportunities for diffusion there, which means an urgent need in Australia, southern Africa and South America to take action. Precaution is strict, and this is already happening in almost every country in the world.
In any case, what concerns researchers in the field of public health is the moment when the new Corona virus will record the highest daily infection rates, because that means that after that point it will be on the way to decline, and then with a degree of certainty it can assess its future with China, and the world as a whole, But there are a lot of problems facing us at this stage. To understand that point, let's compare the spread of "SARS" in 2002 and 2003 and the spread of the new Corona now.
Corona vs SARS
By 2004, SARS had ended, and during the year preceding those events there were already very effective measures to isolate patients before transmission of infection from them to others, but for SARS, mankind was in a lot of luck because our friend, the virus that kills Up to more than a tenth of the patients, it was transmitted from one patient to another after the onset of symptoms (4), which means that there was some time for health care providers to discover and detain the condition before transmitting the infection to others.
As for the new Corona, this is unfortunately not the case. In fact, as the number of cases progressed, it became clear to scientists that the extent of the new virus's work was very wide and included cases (5) in which no symptoms or only some of the sore throats appeared, which means that it can spread much wider than governments or specialists might assume. Both public health.
For this reason, along with other reasons related to the fact that the government will of course not be able to confirm all the infected cases in China, with fears of a degree of obfuscation, a study (6) was recently published in the famous "The Lancet" medical journal to expect that the number of injured in a day January 27 was about 76 thousand cases, while this number was referred to on February 19 as confirmed cases, and with the calculation of escalation rates from January 27 this means that the number of injuries had crossed the barrier of several hundred thousand by the moment you read this the report.
According to a statistical mechanism created by researchers from the London College of Hygiene and Tropical Medicine (7), by the end of February, Corona could reach its peak with a total number of 500,000 cases, in light of the largest quarantine in history around Wuhan and the surrounding cities. Of course, here we mainly talk about the number of injuries in China. Outside it (8), the atmosphere so far is somewhat reassuring, the number of cases is approximately 1100 and the number of deaths is less than 15 by the end of the day (February 21). Nevertheless, the situation in Iran in particular is causing concern, 4 deaths and 18 declared injuries, according to the Iranian Ministry of Health, with fears of obfuscation by the Iranian authorities, and there it stands on the borders of the Arab world.
China as a closed room
At that point, and to understand why the spread of infection is so varied between China and abroad, let's get to know a very important term from the public health world, it's R-nought, the most popular symbol R0, which you see a lot these days if you are interested. The matter and follow up. This indication indicates the number of people who can be infected by one person during the incubation period. Movie films present this number as a very frightening constant, for if this number is 5, for example, then each person will have a disease of 5 and then affect each of them 5 others, and so on until the end the world.
But this indication is, in fact, a flexible number that depends on many criteria. The disease may be highly capable of transmitting to others, such as measles, which has a value equal to 12, but we have tools to resist spread, whether by isolating the patient or by raising the resistance of his body or any other reason On the other hand, the Spanish flu, which killed 20 million people at the beginning of the last century, was valued at 2.4.
The value of the "indication R" varies with time, the number of people exposed to infection, the means of treatment, and a very wide number of criteria that make updating the number a basic necessity with the importance of obtaining it at all. For the new krona, (10) scholars believe it is a number between 1.5 and 3.5. For countries outside of China, there are - as far as we know - high capabilities to limit proliferation. In China itself, some specialists in this range believe that the number has exceeded the possibility of containing the new corona.
Hiroshi Nishiura, an epidemiologist from the University of Hokkaido, joins this team, as he sees (11) that China will not completely stop state life for a long time, and after the holidays are over people will return to work again which opens up better opportunities for Corona to spread, and with the situation In consideration that China has - basically - very few test tools compared to the population, which indicates that the number of infected people is much greater than what is reported, and also because a large proportion of injuries do not have symptoms, our friend expects, in total, the number of infected cases to arrive Nearly half of China's population, around 650 million infections.
According to a study released at the end of January, in the New England Journal or Medicine, the examination of (12) escalation patterns in the first 425 cases of the new corona indicates that the number of patients has doubled completely every week, which opens the door to the possibilities already wide, but in That point must be directed to another question, if it is indeed possible for the number of injuries to rise to the point of hundreds of millions, how many deaths are expected?
New Spanish flu ?!
Here we can be a little optimistic, as the Chinese Center for Disease Control and Prevention issued a few days ago the largest study (13) of its kind, based on data of approximately 72 thousand confirmed cases along with a number of infected cases but without symptoms, and the results came to say that - contrary to what At first glance, Corona appeared to have an average effect on more than 80% of cases, exactly as a normal cold or less, with 14% of cases evaluated to a degree of severity, and only about 5% of cases considered critical, including deaths, which are In most cases, they are in the hospital.
Also, it has been shown that the virus did not cause any deaths in children, despite the infection of children from a very young age of several days, and it also seemed clear that the death rate rises with the rise of two factors, the first is the age, being less than 40 A year makes the probability less than 0.2%, and rises by the eighties, and the second is cardiovascular diseases such as pressure, heart failure, and others. But in any case, it is - on a global level - even 1% means tens of millions of people.
On the other hand, the research work on understanding the Corona virus has evolved a lot. In fact, about a hundred research papers have been issued on the matter since its inception, and researchers from the American National Science Foundation NIH were able, only several days ago (14), at a remarkable speed quickly From reaching the DNA sequence that produces one of the important proteins responsible for the ability of the virus to infect humans, which means a future possibility, and we are talking here about a few months, to discover a new vaccine for the virus that prevents it from binding to human cells.
But in any case, what we have is a lot of possibilities based on very little data available, there is a possibility that China will be able to eliminate the new corona and end up by the end of this year, and there is also a possibility that the new corona will continue to exist as a seasonal injury repeated every year Whether in China or the world as a whole, despite international restrictions imposed on travel to and from China, no one knows where the next strike will come from, and you can consider the Iranian situation as one of those possibilities (15).
It turns into what happened in influenza cases that killed a million people in each of the accidents (16,17) in 1957 and 1968 is also an existing but weak possibility, because we really - as human beings in general - have learned to respond better to epidemics like that, in fact Dealing with the new corona, from an operational point of view, was better than SARS, but the virus itself had different characteristics, which brings us back to the saying of Bill Gates that we mentioned earlier, the world must be better prepared for what is more dangerous, because it is possible.