Wednesday, January 29, 2020

Fear is the biggest threat from the 2019-nCoV coronavirus

The number of confirmed cases of the Wuhan coronavirus has overtaken the 2003 SARS outbreak inside of mainland China, as multiple countries began evacuating their citizens from the city at the heart of the outbreak [CNN].

But scientists outside of China still have no clear understanding of the epidemiology, and as to whether it could become a global pandemic, partly because of the confused and incomplete information coming from China itself.

Growing concerns

In China, where 5,974 people are infected, and 132 have died through Tuesday, there is growing concern. And there are also growing fears around the world too, as countries ban flights from certain parts of China and consider or implement Chinese tourist bans [Jakarta Post] .

The high fatality rate is certainly concerning, but still far less than the fatality rate of SARS and MERS. But there is still a worry this outbreak could pose a serious threat to health on a global scale.

Too early for complacency

The coronavirus, temporarily named 2019-nCoV, has yet to show signs it is something that could become a global pandemic. Nonetheless, it is still too early to be complacent.

Unlike scenarios of viral outbreaks depicted in Hollywood movies such as Outbreak, and more recently Contagion, this virus has been slow to manifest itself.

2019-nCoV was first identified in the Chinese city of Wuhan in December 2019 after people developed pneumonia without a clear cause and for which existing vaccines or treatments were not effective.

Initial numbers of those infected were small, and appeared to only be clustered around individuals who had close connection to a wholesale seafood market in Wuhan which is now widely believed to be the source of the virus.

The Huanan Seafood Wholesale Market, which had over a thousand stalls selling fish, chickens, pheasants, bats, marmots, venomous snakes, spotted deer and the organs of rabbits and other wild animals, was identified by authorities as being the source of infection, given that by January 2020 two-thirds of those shown to have contracted the virus had been exposed to the market. As a result the market was closed on 1st January 2020.

Numbers of those infected at this point were still small, amounting to only 41. However, with testing for the virus only beginning to roll out in other medical establishments it was of course unclear whether this virus had spread widely.

Growing numbers

The similarity of symptoms with that of seasonal flu has also complicated the issue, that being a high fever, dry cough, muscle aches and tiredness. Less frequent symptoms included coughing sputum or blood, headache and diarrhoea.

As tests of suspected victims increased it became clear that the numbers were increasing significantly. On the 16th January the number of those identified as having contracted 2019-nCoV was still only around 45 but had risen to 121 on the 18th of January. By the 24th January some 1,287 people had been found to have the virus and within just another four days that figure had risen to 5,974.

The spread of the virus and indications that it could take up to 14 days to appear raised further concerns. Indeed there have also been reports that some individuals can be asymptomatic but nonetheless still capable of passing on the virus. Such assertions, put out by the Chinese authorities are, however, dismissed by many US experts. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told the Washington Post, "Even if there [is] some asymptomatic transmission, in all the history of respiratory-borne viruses of any type, asymptomatic transmission has never been the driver of outbreaks."

"The driver of outbreaks is always a symptomatic person," Fauci adds.

Unclear information

The lack of clear and accurate information coming from the Chinese has not helped scientists and researchers.

Researchers outside of China are struggling to accurately model the outbreak and predict how it might unfold, in part because the data released by Chinese authorities is incomplete. China has shared information showing when cases were reported, but not when people became ill.

Researchers also want to know more about the incubation period, currently estimated at two to 14 days, and how severe most cases are [WHO document PDF].

Unclear epidemiology

The lack of clear information has not helped in correctly determining the so-called basic reproduction number, sometimes referred to as the R-nought.

The R nought of an infection can be thought of as the number of cases one case generates on average over the course of its infectious period, in an otherwise uninfected population.

According to Dr. Nancy Messonnier, the director of the National Center for Immunization and Respiratory Disease in the US, the R nought of the 2019-nCoV is somewhere around 1.5 to 3 whilst the World Health Organization (WHO) have published an estimated R0 of 1.4 to 2.5. Other teams have since come up with slightly higher values, indeed as high as 5.

Measles, which is one of the most contagious infections in the world, has an R nought of around 12 to 18, by comparison, whilst Polio, Smallpox and Mumps all average at around 5.

The season flu on the other hand has an R nought of around 1, having a range between 0.9 and 2.1.

Researchers caution that R0 estimates come with large uncertainties. But having said that, there is the mortality rate that is less opaque. Currently the number of victims that have died having contracted the virus amount to around 2.3%. With mortality rates of 10% for SARS-CoV and 37% for MERS-CoV, the national and international response might seem to be one of overreaction and panic.

Knowns and unknowns

But there is still much unknown about this new virus and it is not yet clear whether those dying are within a group normally considered to be of a healthy age group.

What seems to be clear is that this new virus is not nearly as infectious as the measles virus, which can live as long as two hours in the air after an infected person coughs or sneezes. And it does not, thus far, seem comparable to the threat posed by the seasonal flu, which has killed at least 8,200 people in the United States so far this season. However, with that said both the seasonal flu and this new coronavirus do appear to have a similar mortality rate of between 2.5 and 3 percent. However, there are established methods of treatment for the seasonal flu, whilst this new virus thus far seems unresponsive to treatment.

Given the potential threat, a battle is being fought on two main fronts; containment and the development of a cure.

Lockdown

Soon after the virus and its source were identified Chinese authorities began a gradual shutdown of places and spaces. This has culminated in the city of Wuhan and several others in Hubei province being essentially locked down.

Both expats and local residents have described surreal scenes as the streets of a city once bustling with over 9.6 million people were now deserted.

"No-one is on the streets and it is very quiet," one woman told Euronews. "It's very strange."

An Irish expat meanwhile told Channel Four News in the UK that it was like a scene from a dystopian science fiction movie.

The virtual lockdown of an entire province, with bans on the use of cars and a shutdown of the public transport system may have slowed the spread,  but the door may have been bolted too late.

Already people having travelled from Wuhan, before restrictions were put in place, have infected other across China. Others too have made their journey across international borders and as of Tuesday this week people in at least 13 countries had been identified as having contracted the virus.

As such many experts feel containment will not succeed. "There is a real possibility that this virus will not be able to be contained," said former CDC director Tom Frieden. Indeed, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, noted in an interview recently, that the virus may have been spreading unnoticed for weeks in Wuhan before it emerged into public view [Washington Post].

As the number of those found to have the virus outside China rose to nearly 100 on Wednesday, British Airways announced it was stopping all of its flights to China. The airline currently flies two daily flights to China, one to Beijing and Shanghai. BA's decision came after UK officials advised against non-essential travel. Other European and US airlines have also adjusted their schedules [Bloomberg]. 

Meanwhile hundreds of British citizens being flown back to the UK from Wuhan on Thursday will be put in quarantine for two weeks on their arrival [BBC].

Finding a cure  

Whilst various countries focus on ways to deal with any potential outbreak within their own borders, the battle is also on to find a vaccine with researchers aiding in the fight against this new virus.

Researchers at a specialist lab in Melbourne, Australia, said they were able to grow a copy of the virus from an infected patient. The sample was sent to them last Friday.

"We've planned for an incident like this for many, many years and that's really why we were able to get an answer so quickly," said

Mike Catton of the Peter Doherty Institute for Infection and Immunity [BBC].

But any vaccine might take weeks or even months to develop, test and approve.

Fear and misinformation

There is one other battle the world faces, however. It is one of misinformation.

Numerous conspiracies have appeared since the outbreak - not to mention videos about bat soup with some users blaming Chinese eating habits for the outbreak. In other online posts there are suggestions that the virus had been known about for years and that it might have even be part of China's "covert biological weapons programme" and may have leaked from the Wuhan Institute of Virology. Then there is the 'fake nurse video' in which a woman claiming to be working in one of the Euhan hospitals claimed that the authorities had covered up the true extent of the outbreak and that over 90,000 people had so-far been infected [BBC].

The coronavirus 2019-nCoV undoubtedly poses a grave risk and could kill a great number of people before it is controlled. However, it is unlikely, at least with current evidence available, to be like the worst case scenarios as depicted in the film Contagion. Whilst there are some similarities to that movie, the most stark similarity is the film tagline "Nothing spreads like fear"

tvnewswatch, London, UK

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