The short answer is, in terms of deaths at least, the current coronavirus outbreak is not as bad as it was initially predicted.
There are currently 60,363 confirmed cases of the novel coronavirus, now named Covid-19, spanning 203 countries or regions following a spike from 45,206 yesterday. However, the majority of these are contained to mainland China. There have so far been 1,370 deaths, mostly amongst the elderly and those with underlying medical conditions. However, included among the dead is Dr Li Wenliang, who tried to raise the alarm about the coronavirus in December, and was consequently targeted for “sharing false information” by Chinese Authorities.
Are we any closer to knowing where the virus came from?
Whilst the finger of blame as to the source of the outbreak has been pointed in multiple directions, the latest candidate has been the humble pangolin. Viruses isolated from pangolins have been found to be 99% genetically identical to the strain currently causing the outbreak. However, with the current emphasis on expediency, this work is yet to be formally peer reviewed and published so should still be treated with caution.
But why pangolins? In Chinese medicine, people believe pangolin scales ground into powder can be used to treat all manor of ailments. Consequently, illegal trafficking of these shy little mammals into China is a huge problem. As with trafficking of anything, import and processing is therefore unregulated, leaving those involved, including the end user open to exposure to all manor of harmful substances and biohazards – including infectious disease.
Modeling is an important part of disease management – and it is improving all the time
An important part of managing this outbreak is understanding the routes and rates of disease spread and being able to estimate fatality rates to plan accordingly. A study from the MRC Infectious Diseases group at Imperial has been published on their site which highlights the decline in estimated fatality rates as the outbreak has progressed and more data has become available.
Prof Martin Hibberd, Professor of Emerging Infectious Disease, London School of Hygiene & Tropical Medicine (LSHTM), commented in relation to this report “The new number crunching from the MRC Infectious Diseases group at Imperial has given some insights into the current case fatality rate estimates and shows how much these can vary at the moment (from 18% to 1%), with the numbers in general coming down over time, as more accurate estimates are made through the increased use of diagnostics in less severe cases. This is reminiscent of the 2009-nH1N1 Influenza strain, where initial estimates were also much higher than the now more established less than 0.1% rate overall. It is worth noting though, that despite this apparently low fatality rate for 2009-nH1N1, this pandemic caused serious additional problems (compared with typical seasonal Influenzas) to healthcare systems worldwide, showing why governments have placed such importance on this new coronavirus virus even as the case fatality rate drops.” He continued “To improve our understanding of 2019-nCoronavirus, new diagnostics are required, that will allow us to understand more about exposure and mild disease, including antibody detection assays to detect past exposure. While these are under rapid development, they may still be slower to be made available than for Influenza, where an established process was already in place for this well-known virus. With these tests in place, more systematic exposure studies can be conducted across populations, as well as more individual information about personal susceptibility following exposure.”
A group from the London School of Hygiene and Tropical Medicine have also released preliminary work estimating that the peak in Wuhan coronavirus outbreak will be mid-late February, but the team emphasize the limitations of the modelling used and will continue to refine the predictions as more information becomes available. Commenting on this latest prediction, Dr Robin Thompson, Junior Research Fellow in Mathematical Epidemiology, University of Oxford said “This is a really interesting analysis. I hope that the peak of the outbreak in Wuhan is coming soon, as this research predicts. One proviso must be that forecasting the peak of any outbreak is challenging, and so there is significant uncertainty in estimates of both the timing of the peak and the total number of cases that will occur.”
An important role for diagnostics and data gathering
Despite the low number of cases in the UK currently, with the ninth confirmed case today, the UK Government have announced that the novel coronavirus “constitutes a serious and imminent threat to public health”.
Dr Al Edwards, School of Pharmacy, University of Reading, said “The government is absolutely right that coronavirus is a serious and imminent threat to people in the UK. The main challenges facing Britain and the wider world are containment, finding everyone infected and stopping the spread, and the treatment of very ill patients, which could easily overwhelm hospitals in any country, however well-developed the health system.”
A significant part of the challenge for successful containment as well as gathering the data necessary for meaningful predictions to be made is effective and sensitive detection of those infected.
Dr Edwards continued “Finding people who have been infected is extremely challenging, but it is essential for containment. We are lucky we do have fairly rapid tests available, based on detecting the virus in patients’ blood samples, for example. However, these will only work when a patient is quite sick. After people get better, or if they have mild infection, the virus can’t be detected. The current rapid tests are based on detecting the nucleic acid of the virus by measuring RNA. This is the genetic “code” of the virus. When the level of the virus drops, a patient doesn’t have very much viral RNA. This is good for the patient but makes the virus almost undetectable.”
Research groups around the world have been working tirelessly to adapt and improve diagnostics tests utilizing multiple sample types and detection methodologies to maximize their sensitivity, speed and efficacy.
“There is another way to detect the virus: find antibodies in the blood. After the patient recovers, they will have lots of antibodies that bind to the virus. Unfortunately, it’s much harder to measure anti-virus antibodies than to detect virus nucleic acids. This type of test will be developed very quickly. I would be very surprised if no-one has developed this type of test yet for urgent research. But as yet there is no internationally agreed “approved” test and agreeing one that works may take some time. At the University of Reading we are trying to develop faster, smartphone-based rapid tests to detect antibodies against viral infection, including in outbreaks such as this one. We have a prototype device tested to try and detect MERS coronavirus infection, but it’s still experimental. We are currently working on proposals to adopt this as fast as possible for use with the current coronavirus outbreak, 2019-nCoV, and SARS” concluded Dr Edwards.
Prevention is better than cure
Travelling across central London this week, I saw little evidence of changes to the daily routines of commuters. The only visible signs of concern at least were a few and I stress A FEW individuals wearing facemasks – ironically at least two with them pulled down below their nostrils. But as someone who has worked in infectious disease research under containment conditions, sights like this make me cringe. Not only are the surgical style masks adopted by many ineffective at keeping out airborne viruses due to their lose fit, but there is a risk for some that they provide a false sense of security. Basic hygiene measures and advise akin to that given during flu season is still the most important message. A recent study showed improving the rates of handwashing by travelers passing through just 10 of the world’s leading airports could significantly reduce the spread of many infectious diseases. Timely and pertinent information in light of the current global spread of coronavirus. So all those times your Mum said “wash those hands!”, she was giving you sound advice for life.