Posts

Showing posts from October, 2020

COVID-19 Infection Fatality Ratio is About 1.15%, new ICL study

Image
 "COVID-19 Infection Fatality Ratio is About 1.15%" - new ICL study Higher than 0.7% IFR in ICL's Oct '20 'fading antibodies' study. Higher than 0.9% UK IFR in the March report predicting ~500k deaths, used to justify lockdowns. Interpret with care... https://www.webmd.com/lung/news/20201030/covid-19-infection-fatality-ratio-is-about-one-point-15-percent IFR - its value & even its definition - is an issue open to some debate. Suggested values vary and comorbidities confuse matters. The WHO, for example, recently implied an IFR of ~0.13%; similar to the sort of value found by John Ioannidis. What actually matters though is not just the probability of succumbing to the virus if infected but also the probability of becoming infected in the first place. Population Fatality Rate (PFR) = probability of infection X IFR ...is a very useful concept for this. We have been modelling & making policy under the assumption that 100% of the population are susceptible ...

Coronavirus: T-cell immunity exists six months after infection, study finds

Image
"Coronavirus: T-cell immunity exists six months after infection, study finds" - Sky https://news.sky.com/story/amp/coronavirus-t-cell-immunity-exists-six-months-after-infection-study-finds-12121816 This must come as quite a shock. Who'd have thought there could be more to immunity than antibody levels? Of course that's not the whole article... The article goes on to say... "But the researchers, from Public Health England and the UK Coronavirus Immunity Consortium, warn that it's still not clear whether the T-cell levels were high enough to protect against re-infection." I suggest referring to known science as a starting point.  There used to be quite a lot of it around, although we seem to have mislaid it recently. To be cautious though I suggest (seriously) this: 1) Treat as true the commonly declared hypothesis that "only people with measurable levels of antibodies have immunity". 2) Work out what should happen if that is the case. 3) Test yo...

WHO Comments imply far lower IFR than previously claimed

Image
An estimated 750M, 10% of world’s population have been infected by Covid-19, says WHO's Dr M Ryan This implies far lower Infection Fatality Rate than previously claimed & potentially significant implications for many countries. https://www.irishtimes.com/news/ireland/irish-news/covid-19-world-in-for-a-hell-of-a-ride-in-coming-months-dr-mike-ryan-says-1.4370626?mode=amp While clearly this is only a "best guess" figure, we can still conduct a rough analysis, leading to an interesting conclusion: 10% of world population ~ 750M Covid-19 deaths to date ~ 1M Implied IFR = 1/750 = ~ 0.13% (IFR = Infection Fatality Rate) An IFR of ~0.13% is almost an order of magnitude lower than the ~1% values seen in much of the predictive modelling that has been used to guide policy, lockdown decisions etc. (E.g. ICL used 0.9% for UK in March - see 2 excerpts below). - Even for a rough estimate, this is a significant difference. An order of magnitude reduction in IFR implies a similar redu...