Beginning from the basic stories, a new virus was first identified in Wuhan, the capital of Hubei province, China. Due to the unexpected rate of hospitalization of similar cases in the city, it got attention. On 31 December 2019, a cluster of pneumonia cases of unknown cause was reported by health authorities in Wuhan. An investigation was launched in early January 2020 by the officials. In the investigation they have found that these cases mostly had links to the Huanan Seafood Wholesale Market (which also sells live animals), consequently, the virus is thought to have a zoonotic origin.
Zoonotic disease in the sense is an infectious disease caused by bacteria, viruses, or parasites that spread from nonhuman animal hosts (usual vertebrates) to humans.
As of March 11, the World Health Organization (WHO) is now describing the situation as a pandemic.
But what is pandemic then? A new word! isn't it? well, this can be a new word for people who are in 2020 only. But this is not a new word to our planet and even many of us know this. A pandemic is a disease epidemic that has spread across a large region, for instance, multiple continents, or worldwide.
Disease and illnesses have plagued humanity since the earliest days. Widespread trade created new opportunities for human and animal interactions that sped up to such epidemics. Malaria, tuberculosis, leprosy, influenza, smallpox, and others first appeared during these early years. The more civilized humans became with larger cities, more exotic trade routes, and increased contact with different populations of people, animals, and ecosystems, the more likely pandemics would occur. If I tell you that this planet has lost millions in pandemic outbreaks, will you agree on it?
Have a look at this image and you can realize the statement.
If you are keen on more specifics about recent pandemics have a look into it.
You can see that the total death is still below the many figures in recent outbreaks but still the whole world just has started to show a big concern to it. Speaking again and again.
But why? Well, if you read this fully you can get it.
This particular COVID-19 rapidly spread from a single area to the entire country or even a continent in just a few days, estimated to be 30. The sheer speed of both the geographical expansion and the sudden increase in numbers of cases surprised and quickly overwhelmed health and public health services in China, particularly in Wuhan City and Hubei Province. When this became an issue in China the other nations have not given proper attention to it and been without seriousness at all.
But now, the whole world is slowly realizing the true dimension of the coronavirus, but still, it’s reacting very slowly.
Just look at this graph first.
This is the epidemic curve of the confirmed cases of coronavirus disease 2019 in China. Daily numbers of confirmed cases are plotted in this graph by date of onset of symptoms (in blue) and by date of diagnosis (in orange). Because, on the retrospective investigation, so few cases experienced illness in December, these cases are shown in the inset. The difference between the cases by date of symptom onset curve (in blue) and the cases by date of diagnosis curve (in orange) illustrates the lag time between the start of illness and diagnosis of COVID-19 by viral nucleic acid testing.
The first few cases of pneumonia of unknown etiology which were noticed by Dr. Zhang are shown in blue boxes on the 26th of December with four people and 3 among them belong to the same family. Dr. Zhang informs the CDC (Chinese Center for Disease Control and Prevention) about this unusual pneumonia and between 28-29th of December, there were 3 more cases.
Most other cases that experienced the onset of symptoms in December were only discovered when retrospectively investigated. The major epidemic response actions taken by the Chinese government immediately are shown in brown boxes. The normally scheduled Lunar New Year national holiday is shown in light yellow from 25th of January to 31st of January. Due to this issue, the government extended the holiday from 1st of February to 10th of February during which attendance at school and work were prohibited (except for critical personnel such as health workers and police) is shown in dark yellow.
On the 23rd of January, the authorities closed down Wuhan city, You can see on that specific day the diagnosed cases were around 400-500 (indicated in orange). But there were actually around 2500 actual cases. And the very next day the authorities closed down another 15 cities. You can see that until the closing down of Wuhan the actual cases getting increased exponentially. But after that cases slow down. And on 1st of February, the actual cases reaches a sudden maximum and after that, it has gone and down and ever since.
Then you can ask what is that in orange and that keeps growing exponentially. Isn't it? You can answer it actually. Those numbers are just the cases that we have already seen in blue, the difference is that is the time those infected people started to show the symptom heavily, getting into the consideration of medicals and the authority. This concept of actual and official cases is a must remember when going further in this entire writing.
Since 2003, the Chinese government has improved its epidemic response capacity on a high scale. Some of these efforts are evident in the response to COVID-19. For example, in the 2002-2003 SARS outbreak, there were 300 cases and 5 deaths already had occurred by the time China reported the outbreak to the WHO. But in the COVID-19 outbreak, only 27 cases and zero deaths had occurred when the WHO was notified. From the time of WHO notification, 2 months elapsed before SARS-CoV was identified compared with only 1 week from the time of WHO notification until 2019-nCoV was identified. But anyhow, when WHO alerted the world, China reported around 7000 confirmed cases and 150 deaths in the meantime it was around 2000 confirmed cases of SARS all around the world when WHO made global alert.
What made this contradictory issue in the case numbers?
But in the case of COVID-19, using the maximum law enforcement this biggest population country became so impressive to bring the exponent raise to almost a flat.
Meanwhile, South Korea, Italy, and Iran had almost a full month to learn, but they didn’t. They started the same exponential growth of Hubei and passed every other Chinese region before the end of February very sooner. Having the very own experience just see how China and these three had done in their own places.
When we are talking about an epidemic (later pandemics) we must know about two key things.
Transmission rate (R0, pronounced R-nought or r-zero) represents the average number of people to which a single infected person will transmit the virus.
Death rate/ mortality rate/ Fatality Rate (case fatality ratio or CFR)
Transmission of infection requires three conditions
An infectious individual
A susceptible individual
An effective contact between them
In this Corona pandemic, the transmission is happening silently. Silent transmission occurs when someone who has contracted the virus shows no symptoms but passes the virus to someone else. In the case of COVID-19, people can transmit the virus before symptoms begin. In this case, about 97.5% of the selected sample exposed symptoms in 11.5 days. This means for complete 11 days the infected person who has no symptoms can transmit the virus.
Strange !!!!
This rare scenario is also known as presymptomatic transmission which is very dangerous and this is why this became a serious issue. Due to this special characteristic of the virus, COVID-19 has R0 in between 2.0 and 4.0. We have seen that the 1918 pandemic caused death to around 40-50 million people all around the world. The R0 value of that pandemic was between 1.4 to 2.8. Additionally, an outbreak with a reproductive number (R0) of below 1 will gradually disappear.
Now you are getting serious right?
This provides evidence that extensive control measures, including isolation, quarantine, school closures, travel restrictions, and cancellation of mass gatherings may be warranted. Asymptomatic transmission definitely makes containment more difficult.– Prof. Lauren Ancel Meyers
Well, look at the graph and realize that how this R0 has contributed to increasing the total confirmed cases.
For further view
Fatality Rate (case fatality ratio or CFR) be in between 2 - 7%. This means 2-7% of affected die because of the disease. According to epidemiologists, this Fatality rate can change as a virus can mutate. 1918 pandemic has around 10% CFR.
Is it an exponent graph?
Then check this graph.
The growth is fully exponential because the infected surpassed the national health potentials of many countries.
Apart from these two key factors, there are three more factors called reproduction number, growth factor, and the serial interval.
The reproduction number or how many people each individual with the virus is likely to infect.
The serial interval
The serial interval of time between one person developing the symptoms of a condition and a second person becoming infected and developing symptoms.
The serial interval of COVID-19 is 4 days. But the shorter serial interval makes an epidemic harder to contain and more likely to spread quickly.
Ebola, with a serial interval of several weeks, is much easier to contain than influenza, with a serial interval of only a few days. Public health responders to Ebola outbreaks have much more time to identify and isolate cases before they infect others. The data suggest that this coronavirus may spread like the flu. That means we need to move quickly and aggressively to curb the emerging threat.
Prof. Lauren Ancel Meyers from the University of Texas at Austin
Growth factor
is the factor by which a quantity multiplies itself over time. The ratio between today's new deaths and new deaths on the previous day is considered a growth factor.
Simply speaking, if a quantity growing by 7% every period (in this case daily) has a growth factor of 1.07. So mathematically you can easily understand that a growth factor above 1 indicates an increase, whereas one between 0 and 1 is a sign of decline, with the quantity eventually becoming zero.
A growth factor below 1 (or above 1 but trending downward) is a positive sign, whereas a growth factor constantly above 1 is the sign of exponential growth.
The growth factor for new cases at the end of 19th of March was 1.27. And this seems a reducing nature. Is that a good sign? What do you say? I hope you can predict few things from the above information.
This is a good sign for now. Just look at the growth factor graph above. You can see there are these positive trends for a lot of time and the peak of the spike is getting reduced slowly since 12th of February which had the growth factor of 6.95 and that was the maximum ever recorded. This is because of the safety measures each country is carrying out. Simply, quarantine of each and every individual. The sudden rise in the trend will be recorded only after a week of identifying the first patient in a country.
Then what about the growth factor of death? Just look at this image.
You can see the growth factor of death on 20th of March was 1.26 at the same time it was 1.11 on 19th of March. This also shows a seasonal variation. You can map the reasons for this sudden rise. The raise is happening exactly because of the mass identification due to the silent transmission. It is just like developing a sphere from a point (ie: first patient).
To understand the fact above just see the outbreak pattern in Italy then.
In Italy total, new cases recorded on the 20th of March was 5986 and that on the 19th of March was 5322. So now you can map how the asymptotic transmission is effective in this COVID-19. Look at the graph below in which I've discussed the total confirmed deaths in the most affected countries China, Italy, and Iran.
Now as per the data, Italy is the nation that has lost a huge number of people to the pandemic. The rate of growth of Iran is slightly similar to that of China while that of Italy is very dangerous.
Also, look at this graph which tells the death numbers per day and how that trend varies in some specific countries.
China has brought the death rate to the limit, that is what we can see in the graph above to this as getting flat at the top. The zigzag pattern of Italy keeps growing to peak and gives no hope till now.
Look at the following graphs which tell the trend of daily cases in specific countries, without China.
This seems that the USA is developing a huge confirmed case these days and approaching Italy. But see there, the growth of Germany!!!
German Chancellor Angela Merkel has warned that up to 70% of the country's population - some 58 million people - could contract the coronavirus. Anthony Fauci, the long-standing director of the National Institute of Allergy and Infectious Diseases, testified said that, Bottom line, it’s going to get worse
There are dozens of countries with exponential growth rates as it. As of today, most of them are Western nations. Why?
Well, South Korean cases have been explored, but have you wondered why Japan, Taiwan, Singapore, Thailand, or Hong Kong haven’t?
Hey writer, where is Taiwan? I can hear it. Well, just check the heading of the graph. Greater than 50! Taiwan had no cases beyond 50 at that moment.
Why this has happened like this?
Well, all of them were already hit by SARS in 2003, and they have learned from it (learning from their own experience is the best teacher isn't it?). They have learned how viral and lethal it could be, so they knew to take it seriously. That’s why all of their graphs, despite starting to grow much earlier, still don’t look exponential. So far, we have stories of coronavirus exploding, governments realizing the threat, and containing them.
For the rest of the countries, however, it’s a completely different story.
Since the vaccine is not going to be available for now, how should we act?
The best way to protect yourself is not, in fact, to just protect yourself. It’s to protect your community.
The very first thing that should be done is shutting down the system of movement. This can be done by closing down the internal and international transports and locking down all the parts of the country once the first patient is identified. Through this, you can easily locate the first phase of the patients and can easily make the others safe from the infection.
But most of the countries failed to impose and control on that way and been without seriousness which had lead to the disaster in many regions (A very fine example is Italy).
So countries giving that much freedom to their people should do what at least to flatten the curve?
Wait, what curve? and why should we flatten it?
Well, every country has its own capabilities. China could build thousands of quarantine centers in weeks but how about the same to Italy? Italy is just fixing the ages to stop giving priority to treatment. Earlier it was 80 and now it dropped to 65. It may go further down. So the capabilities are the things that all citizens must be aware of. Capabilities in the sense the hospitals, supplies, medical staff, available beds and etc.
Simply speaking, look at the above curve. If we are having the entire state's cases under this capability, we can get rid of the big and worse outcomes like what is happening in Italy.
Social Distancing
One very simple thing that we can do and that works. Where? In Singapore! the best example. Further, go back to the Wuhan timeline graph, you will remember that as soon as there was a lockdown and cases went down. That’s because people didn’t interact with each other, and the virus didn’t spread.
The current scientific findings tell that this virus can be spread within 2 meters if somebody coughs. The worst infection then becomes through surfaces. But how?
The virus survives for up to 9 days on different surfaces such as metal, ceramics, and plastics. That means things like doorknobs, tables, or elevator buttons can be terrible infection vectors.
The only way to truly reduce that is with social distancing. Keeping people home as much as possible, for as long as possible until this recedes.
Will it work? bloody hell for god sake it works and worked!!!
Where again? this time for where it worked?
This has already been proven in the past. Namely, in the 1918 flu pandemic.
Containment
Containment is making sure all the cases are identified, controlled, and isolated. Well planned, divide and conquer method. It’s what Singapore, Hong Kong, Japan, or Taiwan are doing so very well yet. They very quickly limit the people coming in, identify the sick, immediately isolate them, use heavy protective gear to protect their health workers, track all their contacts, quarantine them. Also, have asked their citizens who have mild symptoms to stay at home in self-quarantine so that the patients with severe symptoms can be treated at the hospitals. Utilizing the resources they have.
This works extremely well when you’re prepared and you do it early on, and don’t need to grind your economy to a halt to make it happen.
In China they are using 1,800 teams of 5 people each tracking every infected person, everybody they got interacted with, then everybody those people interacted with, and isolating the whole infectious suspects That’s how they were able to contain the virus across a billion people country.
Just imagine what would have happened if they had not done these measures?
Mitigation or Suppression
Mitigation requires a heavy amount of testing, contact tracing, quarantines, and isolation to flatten the curve without stopping the outbreak. It means to let the outbreak grow but the tracing should happen faster and at one instant we can surpass it. And that must be done when we are under the limit
Suppression tries to go one step further and quench the outbreak. It requires heavy social distancing. People need to stop hanging out to drop the transmission rate (R0), bringing the R0 below 1 can make the virus die in time.
What are the trade-offs we could be making to lower the R0?
This is the menu that Italy has put in front of all of us!
Respecting the lockdown laws. Unless there are proven family or work reasons.
The movement inside the areas is also should be avoided unless they are justified for urgent personal or work reasons and can’t be postponed.
People with symptoms (respiratory infection and fever) are “highly recommended” to remain home in self-quarantine.
Standard time off for healthcare workers must be suspended and the service is mostly expected.
Closure of all educational establishments (schools, universities…), gyms, museums, ski stations, cultural and social centers, swimming pools, and theaters.
Bars and restaurants have limited opening times from 0600h to 1800h, with at least a one-meter distance between people.
All pubs and clubs must be closed.
All commercial activity must keep a distance of one meter between customers. Those that can’t make it happen must be closed. Temples can remain open as long as they can guarantee this distance.
Family and friends’ hospital visits must be limited.
Work meetings must be postponed. Work from home must be encouraged.
All sports events and competitions, public or private, must be canceled. Important events can be held under closed doors.
At this level, we can simply help our system to attain control over the virus-like this.
So what should you know?
The coronavirus is coming to you.
It’s coming at an exponential speed. Gradually at the initial level and then suddenly.
It’s a matter of days. Maybe a week or two just to control the spread if you are supporting the state and the front-line workers.
When it does, your healthcare system will be overwhelmed.
Your fellow citizens will be treated in the hallways.
Exhausted healthcare workers will break down. Some will die. Do you want it?
They will have to decide which patient gets the oxygen and which one dies. (as happens in Italy)
The only way to prevent this is social distancing today.
Not tomorrow. Today.
That means keeping as many people home as possible, starting now. We will definitely win this war. Only we have to do is extending the time as much as possible till the vaccine comes.
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