Why we should care about Coronavirus

When I heard China quarantined millions of its population for a new virus, I have been reading about it. Xi Jinping, Chinese President had this to say about Coronavirus in January [18]

"This epidemic is a demon, We cannot let demon hide."

Many people still think coronavirus is just a flu or hoax or its dangers are being vastly overstated. I believe it is not the case because of the following :

1 Many Serious cases

According to Chinese government data [1], 14% of cases are severe requiring hospitalisation and 5% of cases are critical cases. Overall mortality rate was 2.3% which is 23 times higher than flu. Percentage of cases requiring hospitalisation is also 20 times greater than flu[11].

2. Capability to overwhelm cities

It has overwhelmed medical facilities in Wuhan, a city in China having population of 11 million. China has sent more than 30000 doctors in Wuhan. They have converted auditorium into medical facilities. Still as per latest scientific study [2], case fatality rate in Wuhan is estimated to be 8.7%, 87 times more than flu.

A second study [3] estimate case fatality rate in Wuhan as high as 20%. It says the following

In conclusion, our latest estimates of the risk of 2019-Cov deaths in China could be as high as 20% in the epicenter of the epidemic whereas this estimate is around 1% in the relatively mildly-affected areas in China as of February 5th , 2020. Because it is likely that the death risk from 2019-nCov is associated with a breakdown of the medical/health system in the absence of pharmaceutical interventions (vaccination and antiviral drugs), enhanced public health interventions including social distancing, quarantine, enhanced infection control in healthcare settings and movement restrictions should be effectively implemented to rapidly contain this epidemic.

As of March 01, 2020, there are 2978 deaths and 42139 recovery from coronavirus in the world [8], which gives 6.6% mortality rate for the infected patients. Whereas 2761 people have died and 31,190 recovered in Wuhan, implying mortality rate of 8.1%.

2. It is novel

We all have immunity to certain flu viruses. That's why you see many people coughing and sneezing in buses and offices but never get sick. But since this is so novel, no one has immunity to this virus. Hence every one exposed to this virus almost inevitably gets sick.

3 Many asymptomatic cases

A single person infected with coronavirus, boarded Diamond Princess cruise ship. On getting to know this Japanese government quarantined nearly 3600 passengers inside the ship. People were told to wear masks and avoid exposure. Still 700 of 3600 passengers ended up getting infected. Nearly 33% of ship passengers were asymptomatic [4]. And being asymptomatic does not mean they do not infect other people. An asymptomatic women infected 5 of her family members in China [5]. And this is not a rare occurrence, a study [6] showed that both asymptotic and symptomatic patients are similarly contagion.

4. It is very infectious

R0 factor is defined as the expected number of additional cases that one case will generate, on average, over the course of its infectious period in an otherwise uninfected population. As per a study [7], R0 factor of coronavirus is 2.2. A Ro factor greater than one implies that number of people infected by disease grows exponentially unless quarantine measures are taken. Since the disease has very long incubation period (0-24 days), probability of someone passing on this virus is much greater. Unlike normal flu, it also spreads by aerosol transmission meaning that if anyone is in closed space with coronavirus then he is very likely to get infected, even if infected person is no longer present or near [9]. Further unlike normal flu it can spread through fecal oral route [10] meaning communities without proper sanitation are at great risk, like rural areas and slums.

5 Reinfection

There are now multiple reports ([12] [13]) that patients cured from coronavirus have tested positive for coronavirus again. It is not yet known that either virus present inside their body reactivated again or they got reinfected again.

6 Complicated diagnostic test and False Negatives

Diagnostic tests for coronavirus is difficult enough that USA has tested only around 500 people for coronavirus untill 2-3 days ago[16]. Many USA states did not have capacity to test for coronavirus.

Even for those who are tested there are many false negatives [15]. Dr Li Wenliang, the whistleblower doctor who died from coronavirus, tested negative multiple times before testing positive and dying from virus. There are reports of people having up to six negative results before eventually being diagnosed.

7 Risk to India

Spanish Flu was an influenza epidemic which spread during the same period as World War 1. World War killed killed 15-20 million people, Spanish Flu killed 30 million people more than the World War. Its most severe impact was in India where it killed 17 million people [17].

So what we have here, a virus which is highly infectious, capable of infecting more than 20% of world population, which kills those 2% of those affected, for which there are no 100% accurate diagnostic tests and whose symptoms in early stage are same as common cold.

Unless big countries like India, America take draconian measures like China, World is looking at an economic catastrophe.

[1] http://weekly.chinacdc.cn/en/article/id/e53946e2-c6c4-41e9-9a9b-fea8db1a8f51
[2] https://www.medrxiv.org/content/10.1101/2020.02.17.20023630v3.full.pdf
[3] https://www.medrxiv.org/content/10.1101/2020.02.19.20025163v1.full.pdf
[4] https://www.medrxiv.org/content/10.1101/2020.02.20.20025866v1
[5] https://www.nejm.org/doi/full/10.1056/NEJMc2001737
[6] https://jamanetwork.com/journals/jama/fullarticle/2762028

[7] https://www.nejm.org/doi/10.1056/NEJMoa2001316

[8] https://www.arcgis.com/apps/opsdashboard/index.html#/bda7594740fd40299423467b48e9ecf6

[9]https://www.hopkinsmedicine.org/health/conditions-and-diseases/coronavirus/coronavirus-disease-2019-vs-the-flu