The coronavirus outbreak came to light when on December 31, 2019, China informed the World Health Organization of a cluster of cases of pneumonia of an unknown cause in Wuhan City in Hubei province. On January 9, 2020, WHO issued a statement saying Chinese researchers have made “preliminary determination” of the virus as a novel coronavirus.
Since then the thousands of cases of the novel coronavirus have been reported from all the 31 provinces in China. The number of deaths due to the novel coronavirus now stands at 170. Cases have been reported from 15 countries, including India. The novel coronavirus has acquired the ability to spread among humans, with cases of human-to-human transmissions being reported first in Vietnam and Germany.
Coronavirus symptoms can include fever, cough and shortness of breath. The illness also causes lung lesions and pneumonia. Milder cases may resemble the flu or a bad cold, making detection difficult. Chinese researchers have shared the whole genome sequence of the novel coronavirus, however apart from some basic details, not much is known about the virus in terms of its source, precise duration of incubation, severity, and what makes it quite easily transmissible. The current outbreak of novel coronavirus (2019-nCoV) that was first reported from Wuhan, China, on 31 December 2019
Decade-long structural studies by Fang Li of the University of Minnesota, et al. have shown how the SARS virus (SARS-CoV) interacts with animal and human hosts in order to infect them. The mechanics of infection by the Wuhan coronavirus appear to be similar. These investigators used the knowledge they gleaned from multiple SARS-CoV strains -- isolated from different hosts in different years -- and angiotensin-converting enzyme-2 (ACE2) receptors from different animal species to model predictions for the novel Wuhan coronavirus. (Both viruses use ACE2 to gain entry into the cell, but it serves normally as a regulator for heart function.)
"Our structural analyses confidently predict that the Wuhan coronavirus uses ACE2 as its host receptor," the investigators wrote. That and several other structural details of the new virus are consistent with the ability of the Wuhan coronavirus to infect humans and with some capability to transmit among humans.
"Alarmingly, our data predict that a single mutation [at a specific spot in the genome] could significantly enhance [the Wuhan coronavirus's] ability to bind with human ACE2," the investigators write. For this reason, Wuhan coronavirus evolution in patients should be closely monitored for the emergence of novel mutations at the 501 position in its genome, and to a lesser extent, the 494 position, in order to predict the possibility of a more serious outbreak than has been seen so far.
The research is published in the Journal of Virology, a journal of the American Society for Microbiology. The study provides the basic, translational and public health research communities with predictive insights that may help study and battle this novel coronavirus.
The novel coronavirus infection that first broke out in Wuhan, China, has spread to 25 countries so far. At least 361 deaths and 17,205 cases of the virus have been reported from China.
The virus is believed to have originated late last year in a food market in the Chinese city of Wuhan that was illegally selling wildlife. Health experts think it may have originated in bats and then passed to humans, possibly via another animal species.
The World Health Organization (WHO) was alerted to several cases of pneumonia in Wuhan at the end of December. Chinese authorities confirmed they had identified a new virus a week later.
The new coronavirus can be transmitted from person to person, although it is not clear how easily that happens. Most cases so far are in people who have been in Wuhan, family members of those infected, or medical workers.
A virus similar to the SARS pathogen has killed more than 300 people in China and spread around the world since emerging in a market in the central Chinese city of Wuhan.
On Sunday, China's National Health Commission said more than 14,000 people have been infected by the novel coronavirus.
Outside mainland China, there have been more than 100 infections reported in more than 20 countries. The Philippines on Sunday reported the first death from the virus outside mainland China.
The World Health Organization has declared an international emergency over the outbreak.
The researchers say the finding is an important reminder that identifying new viruses in animals and quickly determining their potential to infect people is a key way to reduce global health threats.
SADS-CoV began killing piglets on a farm near Foshan in Guangdong Province in late October 2016. Investigators initially suspected porcine epidemic diarrhea virus (PEDV) as the cause. PEDV is a type of coronavirus common to swine that had been identified at the Foshan farm. Detection of PEDV ceased by mid-January 2017, yet piglets continued to die, suggesting a different cause. Scientists say separating sick sows and piglets from the rest of the herd helped stop the outbreak of SADS-CoV by May 2017.
Investigators confirmed the connection of SADS-CoV to bats by identifying the new virus in the small intestine of piglets from the outbreak. They then determined that the genetic sequence of SADS-CoV is similar to that of a bat coronavirus discovered in 2007 and looked for evidence of SADS-CoV in bat specimens collected from 2013 to 2016 in Guangdong Province. The new virus appeared in 71 of 596 specimens (11.9 percent).
The researchers also tested 35 farm workers who had close contact with sick pigs, none of whom tested positive for SADS-CoV.
Currently six coronaviruses are known to cause disease in people, but so far only two of them -- SARS-CoV and Middle East Respiratory Syndrome coronavirus -- have caused large outbreaks of fatal illness in people.
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