Gerard wrote:Amber G - so what is best estimate of R0 and CFR for this thing?
I am posting the values (see below) which IMO are the current best estimates .. but let me make a few comments:
CFR:
While discussion mortality risk , there is lot of discussion about CFR lot of misunderstanding.
Case Fatality Rate (CFR) metric is
defined as dividing the total number of deaths divided by total number of confirmed cases.
This should not be confused with
Crude Fatality Rate (crude mortality rate) –
probability that a person from a population will die from the disease. It’s calculated by dividing the number of deaths from the disease by the total population.
This is important to differentiate, because unfortunately people sometimes report case fatality rates as the crude mortality rate, and vice versa.
Also, often there are cases where disease is never diagnosed. cases with mild symptoms are often not tested or we have incompetence like CDC in US.
A good graph from our world in data:
****
There is no single case fatality rate for a disease – it is context-specific, changing with time and location
Unfortunately, it is common to report the CFR as a single value.
But the CFR is not a biological constant. The CFR is not a value which is tied to the given disease, but is instead reflective of the severity of the disease in a particular context, at a particular time, in a particular population.
Latest Values: (March 7th - Data)
Case fatality rate globally = 3.4%
Case fatality rate in China: 3.8%
Case fatality rate for the rest of the world: 1.9%
These numbers will change -- It’s currently higher than the estimates of a CFR of around 2% that were published until early February.
My estimation, for India, (or US if we don't goof up ) this will be, when things settle down, < 0.5 %. This assumes our hospitals and health services do not get run-over. (I am using Korea, Singapore data).. For older population and people with other health issues this could be more deadly (5%) -- so it is important to keep it from spreading.
****
R0 - Again it is just a number mostly used in mathematical models. I will put the values here but but it is important to understand their meaning:
WHO's estimate: Ro to be between 1.4 and 2.5.
Other studies ( IMO quite accurate:) bet 2.3 and 3.6
(For comparison, the Ro for the common flu is 1.3 and for SARS it was 2.0.)
It really depends on the environment and lot of other things.
***
I think "doubling time" is more meaningful in understanding - At least this is metric is more popular in Physics.
FWIW: Here is the current value:
China - 21 days
Rest of the world - 4 days.