(yet it was contained in the UK, which is great and suggests I’m talking BS)
I continue to be extremely surprised by the UK decline in numbers. The Netherlands is reporting a current estimated R of 1.1-1.2 for the English strain and 0.8-0.9 for the wild types. They furthermore estimate that just over half of all newly reported cases are English strain by now. But the UK daily cases have dropped by 80% in 40 days, which at a reproduction time of 6 days would mean R = 0.79 throughout.
In the past I suggested a few potential, not mutually exclusive, explanations:
The UK has implemented significantly more effective measures, and if we just copy them we can totally beat the English strain.
The height of the UK peak in the second week of January was caused by Christmas and New Years holiday craze, which caused significant delayed reporting (‘better take that test after I visit all my friends and family, otherwise I won’t be allowed to join them’) and massively overestimates the peak, and also the decay.
The Dutch models are crap.
The UK numbers are crap.
The English strain has spread throughout the London area so rapidly that it hit local group immunity, and the plummet afterwards is caused by a lack of geographical spread. Once this picks up again the UK will see a stark rise in cases.
I previously put my money on hypothesis number 5, but as time goes on it steadily loses credibility. If anybody has a suggestion for what’s going on in the UK right now I’m all ears, I am currently not taking their drop in cases at face value.
I think if you account for undertesting, then I’d guess 30% or more of the UK was infected during the previous peak, which should reduce R by more than 30% (the people most likely to be infected are also most likely to spread further), and that is already enough to explain the drop.
I continue to be extremely surprised by the UK decline in numbers. The Netherlands is reporting a current estimated R of 1.1-1.2 for the English strain and 0.8-0.9 for the wild types. They furthermore estimate that just over half of all newly reported cases are English strain by now. But the UK daily cases have dropped by 80% in 40 days, which at a reproduction time of 6 days would mean R = 0.79 throughout.
In the past I suggested a few potential, not mutually exclusive, explanations:
The UK has implemented significantly more effective measures, and if we just copy them we can totally beat the English strain.
The height of the UK peak in the second week of January was caused by Christmas and New Years holiday craze, which caused significant delayed reporting (‘better take that test after I visit all my friends and family, otherwise I won’t be allowed to join them’) and massively overestimates the peak, and also the decay.
The Dutch models are crap.
The UK numbers are crap.
The English strain has spread throughout the London area so rapidly that it hit local group immunity, and the plummet afterwards is caused by a lack of geographical spread. Once this picks up again the UK will see a stark rise in cases.
I previously put my money on hypothesis number 5, but as time goes on it steadily loses credibility. If anybody has a suggestion for what’s going on in the UK right now I’m all ears, I am currently not taking their drop in cases at face value.
I think if you account for undertesting, then I’d guess 30% or more of the UK was infected during the previous peak, which should reduce R by more than 30% (the people most likely to be infected are also most likely to spread further), and that is already enough to explain the drop.
This is a very good point, and in my eyes explains the observations pretty much completely. Thanks!