London vs New York

Following on from my analysis of the UK regional infection trajectories, I wondered how London would compare with New York City (NYC) and whether there were any useful insight to be gained.

Now the problem with comparing cities in different countries is that you are dealing with different testing, recording and healthcare systems so any analyses produced should always be handled with a degree of caution.

Initially I started with some data on the total cases in NYC which when compared with London on my usual cases per 100K basis did not look right, so instead I have compared the London case data (typically confirmed in the hospital setting) with hospitalisation due to Covid-19 in NYC. This gives the chart below:

What we can see is that despite starting in quite similar positions on 11th March (high growth but low cases per 100K population) the curves quickly diverge - by 19th March NYC had more cases and nearly twice the daily growth rate (bearing in mind this is being compounded day-on-day at this point). This higher rate of cases and growth, meant that once the lockdown was triggered a higher trajectory for NYC was almost inevitable.

By early April this meant a plateau of 123 new cases per day per 100K population being hospitalised in NYC, nearly twice what was seen in London (67). Assuming a similar bed/population ratio in NYC to London, it's not hard to see how NYC was struggling to cope during late March early April - a rough estimate from this analysis suggests NYC would need over 10,000 beds in early April, compared to about 5000 beds in London at peak.