MERS coronavirus - NIAID

Novel coronavirus detected in China – Expert Reaction

A new virus has infected dozens of people in Wuhan City, China.

The virus was detected after more than 40 people were hospitalised with pneumonia in Wuhan City, China and the outbreak traced to a large animal and seafood market. The Centers for Disease Control and Prevention reports that person-to-person transmission of the virus appears limited.

Early this morning, the World Health Organization (WHO) reported that an additional infection had been detected in Thailand in a person who is believed to have travelled from Wuhan City. The WHO said, “it is essential that investigations continue in China to identify the source of this outbreak and any animal reservoirs or intermediate hosts”.

The SMC asked experts to comment on the virus and outbreak. 

Professor Kurt Krause, Professor of Biochemistry, University of Otago, comments: 

“It is important to note that coronaviruses are not uncommon and that they commonly cause respiratory illnesses in people. Their severity varies and ranges from causing severe even fatal pneumonia to causing a more mild cluster of symptoms resembling the common cold.

“You have probably heard of SARS and MERS for example. Both are caused by coronaviruses and they cause severe infections with a high mortality. Today I noticed the draft genome of this new coronavirus was released and it has a genetic relationship to the viruses that cause SARS.

“Certainly, there is a lot more work to be done in terms of studying who is susceptible, patterns of transmission, incubation period, severity as well as things like control measures and determining the location of possible animal reservoirs of infection. It is an important story that deserves a close watch over the next weeks and months.”

Professor Michael Baker, Professor of Public Health, University of Otago, Wellington, comments:

“The present coronavirus outbreak in Wuhan City in China is certainly severe, with one fatality and six other people reported to be severely ill with pneumonia out of about 40 confirmed cases.  However, it does not appear to be highly transmissible.  Cases are largely confined to people who have had exposure to a live-animal market there. There has been no confirmed person-to-person spread, including among several hundred known contacts.  The new case identified in Thailand had traveled from Wuhan and is still being investigated.

“With a newly emerging infectious disease that appears to be infecting humans for the first time, health authorities are interested in three main features: severity of infection, ease of transmission, and controllability.  Severity of infection is measured in several ways, but the key feature is fatality risk. Transmissibility is summarised by the reproduction number, which is the number of people typically infected by each case.  If this number is much above one, then we will see an exponential increase in cases.  A very high number means an explosive epidemic.  This is where controllability comes in, which is the extent to which transmission can be prevented by easily available methods such as contact tracing, isolation, quarantine, treatment, and vaccination (which is not usually available for newly emerging infectious diseases).

“The SARS pandemic in 2002-03 illustrates these points.  It was also a newly detected coronavirus transmitted from an animal reservoir that infected humans. It caused severe respiratory illness with 8,098 reported cases and a fatality risk approaching 10% (774 deaths, 9.6% fatality risk).  It was highly infectious with a reproduction number of 2-4 resulting in rapid spread to case contacts, particularly in hospital settings.  In the end, it was found to be highly controllable with simple measures, notably case detection, isolation and quarantine of contacts.

“The World Health Organization (WHO) has a major clearinghouse role in distributing information about emerging infectious diseases such as this new coronavirus.  Under international law (the International Health Regulations 2005) all WHO member states are required to rapidly report potential emerging health threats such as this novel coronavirus, particularly where they pose a risk of international spread, which is clearly the situation with this emerging viral threat.  The WHO is currently considering whether international measures are needed to control this outbreak. If that is the case, then they could declare it a Public Health Emergency of International Concern.  We are still several steps away from that point.

“The US Centres for Disease Control and Prevention (CDC) also frequently becomes involved in investigating and reporting on such outbreaks. Both WHO and CDC are providing regular updates on this current outbreak and its investigation.”

Declared conflict of interest: None.

The Australian SMC gathered further expert comments on 17 January following the detection of the virus in Japan.

Associate Professor Adam Kamradt-Scott is an expert in the spread and control of infectious diseases at the Centre for International Security Studies at the University of Sydney.

“The identification of a new case in Japan of the novel coronavirus which has caused the death of two people and infected approximately 40 individuals in Wuhan, China, is not an entirely unexpected development.

But it does provide further cause for the international community to act rapidly to try and contain this virus before it spreads further. The more concerning aspect about this latest case is that, whereas the first cases were identified to have travelled to local food markets, the cases in Thailand and now Japan have reportedly not visited these sites, which indicates the virus may have achieved limited human-to-human transmission – although it must be stressed this has yet to be proven.

To their credit, the Chinese Government has been quick to share the genome sequencing of this novel coronavirus, which has assisted us in being able to rapidly test for the presence of the virus in suspected cases. This has enabled the identification of this new case in Japan.

Given that there are direct flights between Sydney and Wuhan, which is currently the epicentre of the virus, there is a reasonable chance that we might see cases emerge in Australia. Given our public health system, we are well-placed to care for anyone who might have contracted the virus, but it is only through international cooperation that we will see this novel pathogen contained.”

Adam has not declared any conflicts of interest.

Professor Raina MacIntyre is Professor of Global Biosecurity and Head of the Biosecurity Research Program at the Kirby Institute at UNSW Medicine

Where has this new virus come from?

“We do not know, but if this has emerged in nature, it may have emerged from an animal species, in the same way that SARS [Severe Acute Respiratory Syndrome] and MERS CoV [Middle East Respiratory Syndrome] appear to have emerged as human infections. Testing of animals in the Wuhan area, including sampling from the markets, will provide more information.”

How infectious is it and is it something we should be concerned about?

“It does not appear to be highly contagious between humans at this stage, based on about 60 known symptomatic cases to date. The cases in Wuhan appear to have been exposed in the fish market, and there have been a few travel-related cases in Japan and Thailand.”

How likely is it that Australia will see cases of the virus here?

“It is always possible we will see a travel-related case here. Wuhan is an economic hub and a much larger city than Guangzhou, where SARS arose, so we may see more travel-related cases. In research which we did on MER-CoV, we showed travel-related risk associated with frequency of international flights in and out of Saudi Arabia. In the same way, the volume of travel from China to Australia will determine the risk of travel-related cases occurring here.”

What do we need to do to protect ourselves from it?

“Avoid travelling to affected areas, and avoid wet markets and other areas where animals are present, if visiting Wuhan. If you think you have been exposed, always mention your travel history to doctors.  We see outbreaks of serious emerging infections occurring when there is a failure to identify the infection initially, such as the hospital outbreak of MERS-CoV in South Korea where the patient travelled from the Middle East and was not diagnosed until he had visited multiple hospitals. All hospitals should practice meticulous triage of return travellers with fever, make sure they do not sit in the waiting room for hours infecting others, and practice isolation and infection control measures if there is a possibility it could be the Wuhan Coronavirus.”

Raina has not declared any conflicts of interest.

Associate Professor Sanjaya Senanayake is a specialist in Infectious Diseases and Associate Professor Of Medicine at The Australian National University

“A new infection has emerged in Wuhan, the 7th largest city in China. It is due to a virus known as a coronavirus which is typically found in animals, and can be transmitted to humans. SARS, which also began in China, and caused a pandemic about 16-17 years ago is also from the coronavirus family.

There have been just over 40 cases identified, nearly all of whom attended a seafood/live market in Wuhan. This suggests an animal source. There have been two deaths, and two cases outside China (Thailand and Japan).

The virus causes a respiratory illness. At this stage, there only appears to be limited transmission between people and the case fatality rate is lower than SARS or MERS. But this could change if the virus mutates.

Wuhan seems to be the only city with the virus, but it is a large city, presumably with a lot of tourists, so more cases outside China, including Australia, could easily occur. Prompt identification of sick people arriving in Australia who have been to Wuhan will help minimise the risk of transmission outside China.”

Sanjaya has not declared any conflicts of interest.