On December 31, 2019, Chinese authorities informed the World Health Organization (WHO) of a problem brewing in Wuhan — the people of the city were showing pneumonia-like symptoms and the culprit seemed to be a mysterious virus.
Their suspicions were right. The Wuhan virus is new. Investigations revealed that the virus — which has killed 26 people and infected over 800 so far — was a type of coronavirus.
Since then, the virus has spread to other Asian countries, including Japan, South Korea, Singapore, and Vietnam. The US has also confirmed its first case since then. Scientists across the globe are putting their heads together to make sense of this new virus, the danger it poses and the means to avert a global epidemic.
“Now, compared to 24 hours ago, I am more concerned about how infectious it is,” Tom Frieden, the former director of the CDC, told Vox. "If the sustained human transmission and a high rate of severe illness are confirmed, then it clearly is an event of international concern," he adds.
What is coronavirus?
Coronaviruses are a group of viruses that have a crown-like (corona) appearance. Most of them do not cause anything beyond a common cold in humans. And a majority of people may have had the virus at some point in their lives, according to the Centers for Disease Control and Prevention (CDC).
So, coronaviruses received little attention until the 2002 SARS epidemic — a virus belonging to this group killed over 800 people.
People contracted the infection from bats, the original host of the virus. Coronaviruses are common in animals too. Occasionally, some of them can make people their targets: they evolve to infect them, for instance, the SARS outbreak in 2002 and the MERS outbreak in 2012, both of which jumped to humans from bats.
In the 21st century, two highly pathogenic human coronaviruses—severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV)—emerged from animals to cause global epidemics with alarming rates of diseases and deaths, according to a viewpoint published in JAMA.
"While MERS has not caused the international panic seen with SARS, the emergence of this second, highly pathogenic zoonotic HCoV illustrates the threat posed by this viral family.
In 2017, the WHO placed SARS-CoV and MERS-CoV on its priority pathogen list, hoping to galvanize research and the development of countermeasures against CoVs," says the JAMA viewpoint.
The Wuhan coronavirus cause is closely related to the SARS virus and spread between people. Health officials are yet to determine how deadly the virus is.
Where did it come from?
Some digging led the authorities to a wildlife market in the city of Wuhan. The initial victims of the virus were a group of people who had either worked or visited the market.
A recent study tried to trace the origins of the virus and found that snakes from Wuhan's wildlife market may have transferred the virus into humans.
But not all scientists agree. There is no proof that viruses such as those behind the outbreak can infect species other than mammals and birds, they argue. "Nothing supports snakes being involved," David Robertson, a virologist at the University of Glasgow, UK, told Nature.
What are the symptoms?
Those infected complain of symptoms such as fever, severe cough, breathing difficulties or shortness of breath. In worst cases, people develop pneumonia, severe acute respiratory syndrome, kidney failure death and even die, says the WHO.
Experts say the virus may take about two weeks to incubate — the time from exposure to the onset of symptoms.
How does it spread?
We do not know that yet. Experts are trying to learn how contagious the virus is: some viruses spread easily from one person to another, like measles, while others are less so. It is not clear yet how easily the Wuhan coronavirus spreads from person-to-person, the WHO adds.
These viruses generally spread when healthy individuals get exposed to respiratory droplets from an infected person when they cough or sneeze.
Other routes include close personal contact, including touching and shaking hands, touching an object or surface with the virus on it and then touching your mouth, nose, or eyes before washing your hands. Fecal contamination could also contribute — albeit rarely.
At this time, it is unclear how easily or sustainably this virus is spreading between people, says the CDC.
As per preliminary estimates from scientists, each sick person can go on to infect between 1.4 and 2.5 additional people. For SARS, the estimate was between 2 and 5.
Is it dangerous?
Around a quarter of confirmed cases have been severe and the current death rate is 4% while the death rate for SARS was about 14 to 15%, according to the WHO. However, they add, the death rate of the current viral illness could change as the outbreak progresses. Among those affected, more deaths are being seen in the older population with health issues, like heart disease, hypertension, and diabetes.
What is being done to contain the spread?
China sealed Wuhan on Thursday, cutting off all modes of transportation into the city, while also suspending bus, subway and ferry service within the city.
Further, the government has banned mass gatherings and asked its citizens to wear masks while stepping out in public. According to the New York Times, the government said the quarantine was needed to "effectively cut off the transmission of the virus, resolutely curb the spread of the epidemic, and ensure the safety and health of the people."
Airports across the globe are screening passengers from Wuhan for signs of illness. The US is also screening passengers. They have also developed a diagnostic test for the virus.
At the moment, the risk of infection with the new coronavirus in the US — where there is only one confirmed case so far — "is way too low to start wearing a face mask. The risk is very, very low to the general public," Peter Rabinowitz, a director of the University of Washington MetaCenter for Pandemic Preparedness and Global Health Security, told the New York Times.
How to keep yourself safe?
Washing your hands and staying away from sick people will help, say experts. Mary Rodgers, a principal scientist in diagnostics at the healthcare company Abbott Laboratories told Newsweek, "It is very likely that this virus is transmitted via the respiratory route, so the usual guidelines for avoiding exposures to respiratory viruses will likely apply—frequent hand washing, covering coughs, and avoid touching your face. These are things you should always follow when traveling to avoid getting sick."