The latest data from in Italy, China and other countries show that there is a strong possibility the trend line of new cases and new deaths is slowing. This means that the measures taken are having an effect, and if we are lucky the virus will “burn out”.
Let’s start with a review of new cases. Many media are showing charts of cumulative numbers of coronavirus infections or cases. This is what cumulative cases or death charts look like:
They show an exponential or near-exponential growth rate, particularly when showing the global number of cases. This causes panic and despair. Rather than doing this, I’d like to look at the daily number of new cases, as this gives us a much clearer picture of what is going on.
Let’s start with China. The Chinese figures of new cases show a clear spike on February 12th, receding dramatically from February 13th and thereafter. The death cases spike about a week later, on February 23rd. Today, the number of new cases and deaths are between 10-30 per day. There is some controversy over how China is counting its cases, but the overall trend is clear.
Italy: On March 22 and 23, the number of new cases in Italy declined rapidly, as did the number of new deaths. It’s too early to tell, since on March 24th the new cases shot up again and remained stable into March 25th. But in general, the situation may be more positive than we hoped.
Greece shows a very different virus transmission rate. There is no consistently upward trend (yet) similar to that seen in high risk countries like Italy or Spain. This may indicate that the measures in Greece have succeeded in limiting the spread of the virus. Or it may simply be too early to tell.
Worldometers does not provide the daily numbers of Cyprus, but I believe Cyprus is following Greece. The virus has not yet taken off and with the measures introduced, hopefully will not. Or, it may simply be too early.
France shows a major spike in cases on March 23rd, and deaths on March 24th. I suspect France is still in the growth stage of the virus, despite the fact that the country started taking extremely serious measures early on.
So, what does this mean? I believe several possibilities exist that we should reflect on:
1. No Testing = No Certainty
Not a single western country is implementing large-scale tests of its population. Testing is reserved for those who show symptoms, have been exposed to someone with the virus, or who work in the healthcare sector.
This means that we don’t know how many people actually have been infected. I believe the number is far higher than what is reported, but those infected are either asymptomatic (they have no symptoms) or the symptoms are not severe.
The following three articles reflect this possibility.
Oxford University’s Evolutionary Ecology of Infectious Diseases group implemented a modelling of COVID-19 that suggests as much as half the UK population could already have the virus, but is asymptomatic.
Greta Thunberg, the climate activist so many people love to hate, contracted the coronavirus and spent 14 days in self-isolation. Check the last two paragraphs of her post below:
As mentioned last week, Michael Levitt, a Nobel Prize-winning biophysicist, makes some useful points about how these models may be wrong. Levitt predicts that the virus will burn out sooner than we think:
When Levitt started analyzing the data on February 1, Hubei had 1,800 new cases each day and within six days this number reached 4,700, he said. “And then, on February 7, the number of new infections started to drop linearly and did not stop. A week later, the same happened with the number of the deaths. This dramatic change in the curve marked the median point and enabled better prediction of when the pandemic will end. Based on that, I concluded that the situation in all of China will improve within two weeks. And, indeed, now there are very few new infection cases.”
2. Chinese Numbers still make no sense
As I mentioned in my first update, the transmission numbers from China make no sense given the reported transmission severity and virulence of the virus. According to the New York Times, up to 7 million people left Wuhan prior to the lockdown on that city. Yet the new cases and deaths are far lower than one would expect in a country of 1.3 billion people.
If the COVID-19 is as severe as described, why are there not more cases reported in China?
3. Erring on the Side of Caution
With these [limited] data in mind, public authorities are almost certainly erring on the side of caution by introducing population lockdowns and flight blockades. Yet this is what we should expect them to do: this is the role of prudent policy-making at a time of real uncertainty but also a very real pandemic.
Since there is no antidote at present, the only method of containing the virus is through social isolation. By self-isolating, we reduce its transmission rate and quite possibly its virulence.
What's Next?
What do I think will happen, based on information until now?
1. I believe a far higher number of us have the virus, but exhibit no symptoms. This means that both the severity rate and the mortality rate arefar lowerthan we currently fear.
2. Why different people move from no symptoms to light symptoms (like Greta Thunberg) to severe symptoms (requiring hospitalization) is unknown. Many sources say thatprior ill health plays a role. In Italy, 99% of those who died had prior illnesses or conditions.
3. If there is no further (negative) mutation, I believethe virus will start to “burn out”in countries that have introduced strict measures within 20-30 days of the start of a significant number of cases. By starting to burn out, I mean that it will reach the apex in terms of number of new cases per day. The apex of the new deaths per day will logically be anywhere from 5-15 days after that.
4. Countries that have delayed the start of extreme measures may probably see a longer growth period prior to hitting the apex of new cases and deaths. Again, this assumes no further mutation occurs.
I base this on the numbers reported from China and South Korea, but also by the prior performance of SARS and MERS. To make a complex hypothesis simple, I believe that as the virus finds itself in a new host (humans, instead of bats), both its transmission rate and its virulence fade over time. Whether that is due to a response from human antibodies, or medication, or an issue endemic to the virus itself, remains to be seen.
This is a highly speculative hypothesis, and should not be construed as permission to go out and start partying. Please maintain caution.
There are numerous problems to this hypothesis, not least of which is the fact that we don’t know if there will be a “second wave” of infection, or a negative mutation to the virus. The viral process also gives no signs to which the rate or efficiency of transmission actually slows. It is assumed that as the virus mutates, enabling the virus to propagate, our cells do not mutate in response.In theory, the gate is left open.
If you are interested in reading more about the scientific basis for this, please see the last four sources at the end of this article.
Finally, I don’t necessarily subscribe to the theory that warmer weather will eliminate the virus. The virus exists and propagates in human blood temperatures of about 37 degrees.
I understand that dry weather conditions and heat could lead to moisture reservoirs to evaporate. But this would mean that as temperatures faithfully change every season, the virus would re-emerge. SARS and MERS did not, at least not over the long term.
In any case, please watch your health and that of your loved ones. Comply, as far as is possible, with the measures introduced. We are a long way from the end of this, but with any luck it may not be as severe as the base case scenario most health ministries are preparing for.
If I or my colleagues can be of any assistance to you, please reach out on email or Skype. I am based here in Cyprus until April 30th.
Cheers,
Philip
Sources:
Worldometers: Daily cases and daily deaths are
Financial Times: Coronavirus may have infected half of UK population
Greta Thunberg: Coronavirus
New York Times: How the Virus got Out
New York Times: Coronavirus Maps
Bloomberg: 99% of those who died in Italy had prior illnesses
Michael Levitt – The Coronavirus will Burn Out
Fehr, Anthony and S. Perlman. Coronaviruses: An Overview of Their Replication and Pathogenesis. Methods of Molecular Biology. 2015; 1282: 1-23. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4369385/
Graham, Rachel and R. Baric. Recombination, Reservoirs, and the Modular Spike: Mechanisms of Coronavirus Cross-Species Transmission. Journal of Virology. March 2010 84 (7) 3134-3146. Available at: https://jvi.asm.org/content/84/7/3134
Guth, Sarah, E. Visher, M. Books and C. Brook. Host phylogenetic distance drives trends in virus virulence and transmissibility across the animal–human interface. The Royal Society Publishing. 12 August 2019. Available at: https://royalsocietypublishing.org/doi/10.1098/rstb.2019.0296
Parrish, Colin, E. Holmes, D. Morens, E. Park, D. Burke, C. Calisher, C. Laughlin, L. Saif and P. Daszak. Cross-Species Virus Transmission and the Emergence of New Epidemic Diseases. Microbiology and Molecular Biology Reviews. 2008 Sep; 72(3): 457-470. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2546865/
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