Saturday, February 08, 2020

Coronavirus 2

8th February 2020

In the previous blog I suggested that a key issue in determining the mortality rate of 2019-nCoV was the lag time between infection and death.  We are not yet sure what it is, but the longer the gap the greater will be the likely mortality rate. And neither do we know the true number of people who have been infected. It is bound to be much higher than recorded but the bigger the number the lower will be the likely mortality rate.

Another key issue is how easily the virus jumps from person to person. In the case of the current outbreak we don't yet have good data on that though it seems to spread more easily than MERS did. The MERS virus seemed to peter out after spreading to several successive people. There's no sign that 2019-nCoV is doing that yet.

The key measure is the reproduction number, RO, the average number of other people that any individual with the virus will infect. We don't yet know what this is, but estimates have put it between about 2 and 4. For an epidemic to stop the RO number needs to be less than 1. The common influenza has an RO just about 1.3 and the value for SARS was 2.

Noting that all data are subject to error, accidental or deliberate, the Woldometer  website  is supplying a constantly updated set of data on the progression of this coronavirus outbreak.


Post a Comment

Subscribe to Post Comments [Atom]

<< Home