EXPERT REACTION: First Australian novel coronavirus case confirmed in Melbourne

What do we need to do now that the first Australian case has been confirmed?

We need to be cautious and take measures to stop the transmission of the virus into Australia and also prevent spread within Australia from infected patients, by isolating and looking after them.

Many media reports are describing the virus as ‘deadly’. What does this mean and is it an accurate description?

This is not accurate. Deadly usually refers to a very high mortality rate of a virus, for instance Ebola has a mortality rate of around 70 per cent which means it kills 70 people in every hundred infected. Compare that to influenza which has around a 1 per cent mortality rate; the novel coronavirus is about 0.03 per cent. So in virological terms the virus is not deadly, but affects the weak, young and old more severely and death can occur.

Do we have any more details about the virus and how infectious it is? Is it changing?

There’s a lot to learn still. We don’t know how infectious it is, but worrying reports suggest transmission before symptoms arise. There are no reports it has mutated.

There have been videos shared on social media that appear to show bodies on hospital floors and doctors collapsing from the virus in China (see here for a collation of Tweets). Should we take these videos with a grain of salt?

I would disregard these types of videos and other rumours that say the virus can be in food imported from China.

Other important question to address:

• Determine how many people are currently infected; Chinese estimates are around 5,000, but international scientists are saying it could be a lot higher, even up to 100,000. There have been 106 deaths so far.
• It's important to work out the animal source it came from to prevent further zoonotic events (animal to human transmission), to help trace the virus and work out possible treatments. In the current data its closest animal relative is a bat virus, but it could have come from another animal, snakes have also been suggested. This is being studied by scientists in earnest.
• An accurate incubation period, currently we are looking at 1-14 days.
  
• The virulence of the virus, which means how ill can it make you?
  
• Work out if we have any current antiviral agents that can inhibit viral replication

The focus in Australia should be on detecting new cases as soon as possible and isolating them, and preventing hospital outbreaks. Protecting our health workers is a high priority. The US CDC recommends respirators for health workers, but the WHO recommends surgical masks, except during certain special procedures. During an emerging epidemic, especially when the epidemiology and transmission is not fully understood, the precautionary principle should be used, and the occupational safety of HCWs should be a high priority.

Early studies of the 2019nCoV shows the virus is found preferentially in lower respiratory tract, which means it could be transmitted in airborne particles. Past studies show that viruses like influenza can hover around in airborne particles for hours in the emergency department. Our research has shown that respirators (such as a P2 mask) are more efficacious in protecting health workers, even against infections assumed to be spread by the droplet route. We need evidence-based infection control polices and a highly precautionary approach to protect Australian health workers, especially as there are still unknowns about the disease. During SARS, many health workers died, and 21 per cent of all cases of SARS were in health workers.  While the overall fatality rate is 2-5 per cent, the fatality rate in hospitalised patients is 15 per cent and higher in patients admitted to ICU.

The genetic data we have seen does not suggest it is mutating rapidly, but we have seen reported cases in China surge since January 20th, to over 1200 cases by Jan 25th. Whether this is because of increased testing, reporting or travel around the Chinese new year is unknown.  Some experts are saying it is the most infectious virus ever seen - that is not correct. At this stage, measles is the most infectious virus we know. If it was highly infectious (more infectious than influenza as suggested by some) we should have seen hundreds, if not thousands of cases outside of China by now, given Wuhan is a major travel hub.

As of January 25th there are about 42 cases reported outside China. It certainly is able to be spread person-to-person, as shown in two studies published this week, but it is still an emerging picture. It is highly concerning that in the last few days, the epidemiology appears to have changed from over 80 per cent of cases being in Hubei province and Wuhan city, to about 50/50 in Hubei province and the rest of China. The more widespread the infection in other parts of the China, the greater the risk of more global spread.

What we need is more data to be published on risk factors, transmission, incubation period and epidemiology, so we can understand what control measures are most appropriate.

The health system is at high risk for outbreaks - including general practice. Potential patients have been advised to call ahead before going to the GP, and that in NSW, GPs have been advised to immediately contact their public health unit if a patient contacts them. Suspected patients will then be assessed by public health and infectious diseases experts. The precautionary principal of exposing as few people as possible to potential new emerging infections is useful for a newly emerged infection, and this can be done by limiting the number of sites where potential infected people encounter the health system, by having adequate isolation spaces, PPE and infection control policies. Some patients may come first to the GP. Surgeries should make sure they have adequate respiratory protection for staff, including reception staff.  Triage is critical, and reception staff should be advised to ask a travel history of anyone with fever and respiratory symptoms. If the patient has travelled to Wuhan or China, they should be moved to a separate room if possible, while staff contacts the public health unit or health department for further advice.