Introduction In my most recent articles on the Omicron variants of Covid-19, I have highlighted the discrepancy between plummeting Active Cases and increasing cumulative Deaths. My model draws attention to this, by comparing the previous alignment of modelled and reported data, prior to February 24th, with the recent divergence. This post continues to summarise theContinue reading “Omicron continues to surprise”
Something odd seems to be happening with the relationship between reported UK Covid-19 cases and deaths in the last few weeks, when deaths have been increasing somewhat more quickly than recently, but cases have declined steeply. My model charts seem to expose this oddity.
In this article, I present a few variations of the current model to illustrate some outcomes depending on different assumptions about the current dominant variant, Omicron BA.2; they are fairly consistent in their forecasts over the 1400 day period of the model, from the outset in February 2020 to December 2023, and show that as NPIs are removed, vaccination is what keeps us safe.
I haven’t needed to make significant updates to my Coronavirus model for a while, because it has been working well.
The original Omicron variant morphed into the new BA.2 variant, and although it seems no more dangerous than its predecessor, it is thought to be between 33%-50% more transmissible. I have assumed the lower value of 33% more transmissive for this post.
I have added Omicron BA.2 as fifth variant v5 to my model, with 8 times the transmissibility of Delta, compared with the original Omicron variant v4 in the model, at 6 times the Delta transmission rate.
While it is still very early days, both in the New Year of 2022 and also for the Omicron variant, this post adds to my recent 19th December update with a summary of further runs of my model for higher transmissions settings. Last time I ran options up to three times the transmission rate of the Delta variant, and I have now looked at transmission up to five times the Delta rate.
I have run updates to my model for lower and medium vaccine efficacy to Omicron, and lower, medium and higher virulence and mortality, and continue to compare with reported data. While evidence is still in short supply, nothing has firmly contradicted the impression that Omicron is highly transmissive, as well as being possibly less virulent.
Omicron is feared to have higher infectiousness than the Delta variant, with even greater concerns should it turn out to cause more severe symptoms, higher mortality, and possibly worst of all, if it were able to evade current Covid-19 vaccines. I have made some parametric runs of my model to assess the possible effects.