The case numbers for COVID-19 have risen significantly over the last few days and are now at just under 3,000 cases per day.
We have been told by Minsiters and the Deputy Chief Medical Officer that these cases are primarily in young people. So, why should we be concerned
with COVID transmission in young people when they are statistically unlikely to have severe symptoms or be hospitalised or die?
We can look at other countries to see what may happen in the coming weeks.
Various authors have plotted cases vs age vs time. On the x axis is time, on the y axis are ages. Look at weeks S31/S32 (semaine/week 31 and 32). Some incidence in 20-29 year olds. But in week S33, this spreads to 30-70 year olds. And then in week S35 and S36, cases in 70+ year olds.
We have known this for some time. Here is data from Florida from July.
Same thing. Starts with young people and spreads to older age groups.
Here is the UK data for COVID mortality from Public Health England / Joint Biosecurity Centre / NHS Test and Trace. Very few (but some) deaths in young people. So we may not see significant deaths filtering through for a few weeks
Chart 2(b) in the PHE Surveillance report is the one to watch. These data lag by a couple of weeks
but I anticipate cases spreading up through the age pyramid in the next couple of weeks. Which I anticipate will lead to increased hospitalizations in the week after that, and increased deaths a few weeks from that. But this is not inevitable: we need to go back to the fundamental mitigations of social distancing, hand washing, and mask wearing, and not forgetting that the virus is still very much with us.
Update 13 September 2020
Public Health England have released their latest surveillance report and I have made a heatmap for English cases. The data is a week old. We can see high incidence in the 20 to 29 year olds spreading to older ages. I expect this to continue over the coming weeks.
Update 20 September 2020
Here is the heatmap produced for the data published on 18 September. We see an incidence of 20 cases per 100,000 in the over 80s for the most recent week. But look closely at the figure to the left – 21. This is the same as the top right cell in the heatmap above. What is very worrying is that this figure has changed, since PHE publish their data a week in arrears. This imples that indiviuals are having cases included over a week late. This indicates a potential failure in getting these results processed by NHS Test and Trace.