We hear a lot about younger people being more at risk from this new pandemic. I’ve been thinking about how to “see” this clearly. Here is my first attempt.
This first graph shows the age distribution of the NSW population (source: ABS Census 2006):
This second graph shows the distribution of swine flu cases in NSW (source: NSW Health: Weekly Epidemiology Report, July 15th). This graph takes into account all the cases of Swine Flu reported in NSW so far (since the start of the pandemic) and looks at the percentages by patient age:
This next graph just puts the two together:
The final graph looks at the difference between the two columns. Where the column is positive, an age group is over represented and, in theory, more vulnerable to Swine Flu. Where a column is negative, the age group is under-represented (compared to its population) and is, in theory, less vulnerable to Swine Flu.
There are lots of criticisms you can make of this approach:
- Younger peoples’ lifestyles mean that they are in more public places (schools, crowds etc) and are therefore more likely to be exposed to any virus circulating. So, they may not be more “biologically” vulnerable: it’s just lifestyle.
- We really need to know what the distribution of seasonal influenza cases is: this would tell us if this pandemic influenza is targeting young people more than normal.
I think the Epidemiological Report from NSW Health has some good figures on this last point and I hope to post in this a bit later on.