A new virus, part of an old well-known family of viruses, has suddenly erupted on to the world stage, rapidly making thousands ill, and already causing hundreds of deaths.
It’s formal name is 2019-nCoV, and it’s nickname is the Wuhan coronavirus. The formal name indicates time, and species. The time is the year it first was identified, 2019, and the first case was described in December of 2019. The “n” stands for novel, meaning it is new. CoV is an abbreviation for coronoavirus, it’s species.
The Wuhan nickname derives from where it first appeared, Wuhan, China, an ancient, beautiful city of gardens, now a huge city of over 19 million people across its metro region.
We are visiting our family in Hong Kong now, and so am able to report on this new virus, erupting not far from here, and appearing here in Hong Kong.
What is a “corona” virus?
All the viruses are classified into various groups. Some groups are very well-know, such as the herpes virus, named for looking like snakes under the electron microscope (herpes means snake in Latin). The coronavirus group is named for the fact that each of such viruses have proteins in their shell that form spikes. All the spikes make the sphere look like it has a corona like the sun, and the word corona means crown in Latin.
All viruses have two main parts- a set of genes, and a protein coat. The protein coat’s job is to crack the lock of the cell to infect, to get the viral genes into the cell. The viral genes job is to force the cell to make copies of the viral genes and plenty of protein coats. All this material combines to make a zillion units of viral genes packed inside the protein coats, that is, viruses.
Coronaviruses are no exception, their genes are in an RNA format, ready to go inside their target cells to force them to reproduce the virus. As noted their viral coat seems to have a corona.
Although the Wuhan virus is new, coronaviruses are not. Ever had a cold? There is a good chance it was caused by a coronavirus. In humans, the protein coats of coronaviruses know how to break into the cells that line the airways: nose, throat, and lungs, and the eyes. This makes coronaviruses beyond common, really more universal.
The old, typical coronaviruses cause typically mild illnesses, like colds, not very dangerous.
How do new coronaviruses appear?
There are now two entirely new coronaviruses to humanity. The first was called SARS, and turned out to be quite deadly, killing over 10% of people who were infected. It was originally a common coronavirus in bats. A set of bats, horseshoe bats in the Yunnan province of China have been found to carry coronavirus of the same genetic profile as human SARS. The bats would bite Asian palm civets, and one year about 10,000 of these animals were slaughtered and sold in a market in Guanzhou, China, just north of Hong Kong. The SARS virus was transmitted to bat, to civet, to humans. SARS erupted in Hong Kong in 2001 and was one of the only diseases to effectively be snuffed out by quarantine, no cases have appeared in the world since 2004. Bats still carry this virus, so a transmission to a human may yet occur again in the future.
The current Wuhan coronavirus appears to have appeared via markets in Wuhan selling bats and snakes. Some suggest that once again the transmission of a bat coronavirus into another animal, then human, led to the eruption of a new coronavirus, this time the Wuhan coronavirus.
Why are new coronaviruses so much more dangerous than old ones?
Viruses, and all germs, face a limit to their lethality. If they kill too well, the hosts that allow them to spread start disappearing, spread ceases, and the germ fails. That is why overt time, infections tend to get milder. The coronaviruses that cause common colds have likely been infecting humans for thousands of years, some estimate say they emerged 10,000 years ago! That’s long enough for evolution to lead to a balance- the virus can spread, cause some misery like a cold, but not kill people.
A new virus erupts on the scene and can kill many people before evolution begins to favor viruses that are not deadly. The influenza virus is another good example of virus that jumped from animal to human, creating deadly infections that over time have mellowed out to be fairly harmless. The animals in this case were domesticated animals, and the play of infecting animals then humans continues to this day, the virus has sustained its ability to spread across humanity for thousands of years, and still continues to cause death, but at less than 1% of cases.
Can you stop a virus from spreading?
The answer historically is usually a very dramatic no. A great article in the NY Times chronicles the failure of quarantine, https://www.nytimes.com/2020/01/27/opinion/china-wuhan-virus-quarantine.html?action=click&module=Opinion&pgtype=Homepage .
The word quarantine comes from the Italian quaranto giorno, which simply means 40 days. It was once believed that whatever caused bubonic plague in the 1300’s went away after 40 days. Take a group exposed, seal them away for 40 days, and spread would cease. People were boarded up, literally, in their homes for over a month, and what was the upshot- the Black Death raged completely unaffected.
A more recent failure was the school policy of keeping every single child out of school if they had chickenpox until all rash healed. This policy was followed at nearly 100% rates, yet the number of kids who got chickenpox pre-vaccine was nearly 100%. A stunning 100% failure rate to stop the spread.
We can all see the dramatic failure of all our ideas to stop the spread of colds, including staying home while sick, washing hands, covering mouths and noses when coughing, the virus still spreads mighty fine anyway.
Two viruses I know stopped spreading with isolation measures. The best success in history was the SARS virus. Hong Kong imposed true quarantine measures and the virus stopped spreading and ceased to infect humanity. No other virus I know of disappeared all together from humanity solely by isolating cases. A milder case is AIDS. In communities where safe sex practices are actually practiced, the spread withers. It is of course not gone, safe sex is not fully practiced. But no other examples come to mind.
China would like to repeat the SARS success, and has closed travel to 35 million people near Wuhan, and closed all schools in China and forced work places to stay on vacation across all of China indefinitely, we will see if it works this time.
Viruses are an ancient form of life, have learned to spread long before humans evolved, they spread.
What illness does the Wuhan coronavirus cause?
Like other coronaviruses that sicken humans, it causes mainly colds. It focuses infection on tissues that touch air- nose, throat, lungs. It turns deadly when the viral infection of the lung creates intense inflammation causing the lungs to swell, aka a pneumonia. When bad enough, air no longer exchanges, the lungs fail, and death follows.
- Humanity faces a new enemy, the Wuhan coronavirus, technically 2019-nCoV.
- Coronaviruses are not new, we know humanity has been infected by them for over 10,000 years, and are a major cause of common colds. Everyone has had one.
- New coronaviruses seem to happen when a coronavirus from a bat transmits to a new animal that humans then eat. That happened with SARS via civets, and now with the Wuhan coronavirus via snakes.
To your health,
Dr. Arthur Lavin
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