A novel virus first detected in the central Chinese city of Wuhan in December has claimed more than 300 lives and infected about 14,500 people.Â
The virus, currently dubbed 2019-nCoV, was pinned down after a spate of pneumonia-like illnesses appeared in the Chinese province of Hubei. It was first reported to the World Health Organization on Dec. 31 and in the intervening month scientists have, which include the deadly SARS and Middle East respiratory syndrome.
On Jan. 30, a special WHO committee declared a of international concern, citing “the potential for the virus to spread to countries with weaker health systems.” Human-to-human transmission has been confirmed outside China, including in the US, leading authorities around the world to begin limiting travel and enforcing quarantines to guard against the spread.Â
On Jan. 31, US Secretary of Health and Human Services Alex AzarÂciting the nation’s intention to protect and respond to the outbreak, while noting “the risk to Americans remains low.” As part of the response, any foreign nationals who have been in China will be barred from entering the US. Starting Sunday, US citizens who have visited Hubei province, where the outbreak began, will be quarantined for up to 14 days, while those traveling through other regions in China will be monitored and have to self-quarantine.Â
Japan and Australia followed suit. As three new cases were announced Jan. 31, Scott Morrison, the Australian prime minister, announced those traveling from mainland China would be denied entry into the country from Feb. 1 onward. Shinzo Abe, Japanese prime minister, said anyone who had visited Hubei province in the last 14 days would be barred entry.
The situation is rapidly evolving. We’ve collated everything we know about the novel virus, what’s next for researchers and some of the steps you can take to reduce your risk.
What is a coronavirus?
Coronaviruses belong to a family known as Coronaviridae, and under an electron microscope they look like spiked rings. They’re named for these spikes, which form a halo or crown around their viral envelope.Â
Coronaviruses contain a strand of RNA within the envelope and, as a virus, can’t reproduce without getting inside living cells and hijacking their machinery. The spikes on the viral envelope help coronaviruses bind to cells, which gives them a way in, like blasting the door open with C4. Once inside, they turn the cell into a virus factory, using its molecular conveyor belt to produce more viruses, which are then shipped out of the cell. The virus progeny infect other cells and the cycle starts anew.
Typically, these types of viruses are found in animals ranging from livestock and household pets to wildlife such as bats. When they make the jump to humans, they can cause fever, respiratory illness and inflammation in the lungs. In immunocompromised individuals, such as the elderly or those with HIV-AIDS, such viruses can cause severe respiratory illness, resulting in pneumonia and even death.
Extremely pathogenic coronaviruses were behind SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome) outbreaks in the last two decades. These viruses were easily transmitted from human to human. SARS, which showed up in the early 2000s, infected more than 8,000 people and resulted in nearly 800 deaths. MERS, which appeared in the early 2010s, infected almost 2,500 people and led to more than 850 deaths.
Where did the virus come from?
The virus appears to have originated in Wuhan, a Chinese city about 650 miles south of Beijing that has a population of more than 11 million people. The Huanan Seafood Wholesale Market, which sells fish, as well as a panoply of meat from other animals, including bats and snakes was implicated in the spread in early January.
Prestigious medical journal The LancetÂ published an extensive summary of the clinical features of patients infected with the diseaseÂ stretching back to Dec. 1, 2019. The very first patient identified had not been exposed to the market, suggesting the virus may have originated elsewhere and been transported to the market, where it was able to thrive.
Chinese authorities shut down the seafood market on Jan. 1.Â
Markets have been implicated in the origin and spread of viral diseases in past epidemics, including SARS and MERS. A large majority of the people so far confirmed to have come down with the new coronavirus had been to the Huanan Seafood marketplace in recent weeks. The market seems like an integral piece of the puzzle, but researchers continue to test and research the original cause.Â
An early report,Â published in the Journal of Medical Virology on Jan. 22, suggested snakes were the most probable wildlife animal reservoir for 2019-nCoV, but the work was soundly refuted by two further studies just a day later, on Jan. 23.
“We haven’t seen evidence ample enough to suggest a snake reservoir for Wuhan coronavirus (2019-nCoV),” said Peter Daszak, president of nonprofit EcoHealth Alliance, which researches the links between human and animal health.
“This work is really interesting, but when we compare the genetic sequence of this new virus with all other known coronaviruses, all of its closest relatives have origins in mammals, specifically bats. Therefore, without further details on testing of animals in the markets, it looks like we are no closer to knowing this virus’ natural reservoir.”
Another group of Chinese scientists uploaded a paper to preprint website biorXiV, having studied the viral genetic code and compared it to the previous SARS coronavirus and other bat coronaviruses. They discovered the genetic similarities run deep: The virus shares 80% of its genes with the previous SARS virus and 96% of its genes with bat coronaviruses. Importantly, the study also demonstrated the virus can get into and hijack cells the same way SARS did.
All good science builds off previous discoveries — and there is still a lot to learn about the basic biology of 2019-nCoV before we have a good grasp of exactly which animal vector is responsible for transmission — but early indications are the virus is similar to those seen in bats. A report by the New York TimesÂ on Jan. 28 suggested the Chinese horseshoe bat could be the main culprit.
How many confirmed cases have been reported?
Authorities have confirmed over 14,000Â cases as of Feb. 1. The bulk are in China, but cases have been confirmed in Thailand, Japan, South Korea, Malaysia, Sri Lanka, Vietnam, Cambodia, Nepal and Russia. In Europe, Germany, Finland, France, Italy, Spain, Sweden and the UK have confirmed cases. Cases have also been seen in India and the Philippines.Â
In the US, eight cases have been confirmed: three in California, two in Illinois and one each in Washington state, Massachusetts and Arizona. Canada has four confirmed cases. On Feb. 1, Australia’s confirmed cases jumped to 12.
Almost 50,000 people are being tracked as of Feb. 1. According to CGTN, a Chinese media service, 339 people have recovered.
Here’s the breakdown as it stands:
- China:Â 14,390 confirmed cases (Hong Kong: 14; Macau: 7)
- Japan:Â 20 confirmed cases Â
- Thailand:Â 19 confirmed casesÂ
- Singapore: 18 confirmed cases Â
- South Korea:Â 15 confirmed casesÂ Â Â Â
- Australia:Â 12 confirmed cases
- Taiwan: 10 confirmed cases
- Malaysia:Â 8 confirmed cases Â
- US:Â 8 confirmed cases
- France: 6 confirmed cases
- Vietnam:Â 6 confirmed casesÂ Â Â
- Germany:Â 7 confirmed cases
- United Arab Emirates: 4 cases
- Canada:Â 4 confirmed cases
- UK:Â 2 confirmed cases
- Italy: 2 confirmed cases
- Russia: 2 confirmed cases
- Spain: 1 confirmed case
- Cambodia: 1 confirmed case
- Nepal: 1 confirmed case
- Sri Lanka: 1 confirmed case
- Philippines: 1 confirmed case
- Tibet: 1 confirmed case
- India: 1 confirmed case
- Finland: 1 confirmed case
- Sweden: 1 confirmed case
You canwith this handy online tool, which is collating data from a number of sources including the CDC, the WHO and Chinese health professionals. (Note: There may be differences in our reports and the tracking tool.)
How many deaths have been reported?
The death toll stands at 304.Âpassed a grim milestone on Jan. 27, with the confirmation that 100 people had been killed by the novel virus. As of Feb. 1, the
No deaths have been recorded outside China.
How do we know it’s a new coronavirus?
In short, science!
The Chinese Center for Disease Control and Prevention dispatched a team of scientists to Wuhan to gather information about the new disease and perform testing in patients, hoping to isolate the virus. Their work, published in the New England Journal of Medicine on Jan. 24, examined samples from three patients. Using an electron microscope, which can resolve images of cells and their internal mechanics, and studying the genetic code, the team were able to visualize and genetically identify the novel coronavirus.
Understanding the genetic code helps researchers in two ways: It allows them to create tests that can identify the virus from patient samples, and it gives them potential insight into creating treatments or vaccines.
Additionally, the Peter Doherty Institute in Melbourne, Australia, was able to identify and grow the virus in a lab from a patient sample. They announced their discovery on Jan. 28. This is seen as one of the major breakthroughs in developing a vaccine and provides laboratories with the capability to both assess and provide expert information to health authorities and detect the virus in patients suspected of harboring the disease.
How does the coronavirus spread?
This is one of the major questions researchers are still working hard to answer. The first infections were potentially the result of animal-to-human transmission, but confirmation that human-to-human transmission has followed was obtained in late January.