July 31, 2022 Analysis of EU national data
This is an update to the analysis approach first used for July 17 and July 24 data. See the description from those page for background about the analysis. The method uses hospital admission data alone to estimate population immunity by the shape of the BA.2 wave.
Model fits to data
The figures below show the updated fits of the simple model to six nations. Unlike the previous week’s data, it is very clear that the BA.5 wave has recently peaked in hospital admissions for all these nations. The immunity escape fraction for BA.5 fit from these data are somewhat lower than from the previous week.
Belgium
France
Ireland
Norway
Switzerland
United Kingdom
fit results
| Country | alpha (BA.2) | alpha (BA.4/5) | escape frac | hosp frac |
|---|---|---|---|---|
| Belgium | 1.42 | 2.65 | 0.06 | 0.0117 |
| France | 1.09 | 1.84 | 0.12 | 0.0092 |
| Ireland | 0.7 | 0.78 | 0.35 | 0.0057 |
| Norway | 0.71 | 1.88 | 0.09 | 0.0035 |
| Switzerland | 1.13 | 1.34 | 0.16 | 0.004 |
| United Kingdom | 0.83 | 1.3 | 0.17 | 0.0101 |
- alpha: transmission rate
- escape frac: fraction of BA.1 and BA.2 infections that BA.4/5 infections escape
- hosp frac: fraction of infections that are collected in hospital admission data. These are fixed to the values from the July 24 analysis.