4 ms·
I believe you understand that R0 is not only a function of biology but of human behavior, density, and ventilation. If biology becomes twice as effective and al
by pama 5y ago
I believe you understand that R0 is not only a function of biology but of human behavior, density, and ventilation. If biology becomes twice as effective and all else stays the same, R0 doubles. The paper you cite [4] is about the British variant, alpha; it was estimated in that paper that alpha was 43 to 90% more contagious than the original strain. Delta is way stronger than alpha, which is why it is now the dominant strain in the UK. I don’t care much about R0 as a global or country average, but delta being 2 to 3 times worse than the original is no surprise, but rather common sense based on the rate it outpaces other weaker variants.
- raphlinus 5y agoYou're correct that paper is about alpha, not delta. Apparently the CDC official pages haven't been updated with delta, but when they are (based on leaked internal presentations) it's likely it will have the much higher R0 estimate as you say. I personally remain skeptical that an R0 of 8 will hold up once biological evidence is taken into account. Reasonable people can disagree.
- NoPie 5y agoBut then it doesn't make sense to talk about R0 of a specific delta variant at all because that R0 for delta will be different for different seasons, different countries, even different cities etc. Instead you could say current R0 in London is 8 (or whatever) and it is mostly delta variant.