The contagious nature of the novel coronavirus can be gauged from the fact that it attained pandemic proportions within less than three months of it being discovered.
The infectious dangers of COVID-19, the novel coronavirus
More than one million cases of COVID-19 (the disease caused by the novel coronavirus) have been reported from 160 countries around the world, a quarter-million being discovered in the United States alone. This is as of March-end 2020.
More than 50,000 people have succumbed to this disease and many countries are failing to stop its spread. The figures world over are rising on a daily basis in almost all countries in spite of lockdowns being declared in many countries.
Those supposedly living in protection have not been spared. The COVID virus has infected prime ministers, royalties and other leaders.
SARS epidemic (Severe Acute Respiratory Syndrome ) of 2003 in China and MERS outbreak together killed fewer people overall than this virus did in less than two months.
Both these diseases were also caused by the coronavirus but the strains were different. The name given to the two viruses is SARS-CoV and the MERS-CoV.
The World Health Organization (WHO) has named the present coronavirus strain as SARS-CoV-2. It is not similar to the SARS or MERS virus nor the influenza virus.
It has evolved into a different strain with a higher capacity to spread. However, the mortality rate is less than that of the MARS and the SERS virus.
The SARS and MERS viruses were easily contained but despite war-like efforts by almost all countries of the world, the novel coronavirus continues to spread.
Here is the comparison chart:
In 2015 and 2016, during the epidemic of the Zika virus, there were more than 500,000 cases suspected of being infected. But, the death toll was only 18.
What makes the contagious nature of the virus most dangerous is that it is very infectious during the earliest stages of the illness. This is the time when the person has no symptoms and feels fine or may complain of a mild headache, low fever, and dry cough.
He is not on the suspect list and inadvertently moves on spreading the virus through his cough and sneezes and from object to object with his touch. This spread called asymptomatic transmission is responsible for 25 percent of the transmission.
Other studies claim that nearly half of the patients (50%) are infected by people who aren’t coughing or sneezing yet and are asymptomatic.
An infected person may not develop symptoms for up to 14 days after catching the virus. And, by the time he is suspected, enough damage is caused.
During coronavirus infection, the viral load is maximum later on during the infection period and large numbers of the infectious virus are shed as symptoms begin to subside over long periods.
Compare the contagious nature of the flu virus and the coronavirus.
A person with the common flu (influenza) will on an average pass on the virus to 1.4 people. Another ten cycles of this interaction mean 14 people will be infected.
The coronavirus is three times more infectious than the flu virus. So, one infected case will pass it to three people and those again likewise will pass it to nine people; at the end of ten cycles, you will have 59,000 people infected.
That is why self-isolation assumes so much significance. It is not just for your sake but also for the sake of society.
When influenza broke in 1918, after the First World War, the influenza virus infected 50 million people worldwide of which 5 million people died. That’s a mortality rate of 10%!
We didn’t know much about the influenza virus then. Today, we know what the flu virus is and vaccinations are available against it. Today, flu kills less than 1% of the infected people.
The coronavirus is an unknown enemy. We still have not understood it well yet. Research is on at all fronts and we shall soon know whom or what we are dealing with.
Here we have a virus that has a tremendous potential to spread,
- But whose transmission we have not yet fully understood
- For which we have no vaccine
- No treatment
- And whose case mortality we have not yet fully understood
However, the only heartening time-proven news is that the spread of this virus can be contained if strong measures are enforced.
Mortality rate
As of today, April of 2020, the mortality rate of COVID-19 as quoted by the World Health Organization (WHO):
“The mortality rate for COVID-19 is 3.4% globally, higher than previous estimates of about 2%.” However, the mortality rate varies geographically and tends to show slightly different rates in different places.
As against that, the mortality rate of the influenza virus is less than 1%. The reason for this is that the yearly vaccine for this virus has been developed, which gives a fair amount of immunity to the vaccinated person.
As against that, the novel coronavirus still stands in the grey area and a vaccine for this virus is still to be developed. Efforts towards this end are on and hopefully, we shall see an effective vaccine soon.
Children are the least vulnerable and if infected they usually tend to remain asymptomatic. The mortality rate among children is practically zero.
How long after recovery are you infectious?
Right now, the Centers for Disease Control and Prevention (CDC) says that people can stop isolating themselves if they have been free from fever for 72 hours, they are now asymptomatic and at least seven days have passed since they first felt sick.
