The number of cases of U.S. coronavirus B117 variant in the U.S. doubles about every 10 days, a new study estimates.
It comes after the Centers for Disease Control and Prevention (CDC) warned that the variant could be dominant in the U.S. by March – a message repeated by the group’s director Dr. Rochelle Walensky yesterday.
But experts are divided about what that might mean.
Washington University computer biologist Dr. Trevor Bedford says the variant – as well as others that have been exposed or introduced to the U.S. – will slow down the whole disease. -dis spread, but they are not sure to bring a big spring wave of disease and death.
On the other hand, an economist and moderator at Pantheon Macroeconomics predicts that the slow pace of vaccination combined with lax restrictions could allow new cases of the spike range to 400,000 per day by the end of April.
Their controversial prophecies mirror the advice of public health officials like Dr. Walensky and Dr. Fauci, who may feel paradoxical: The worst pandemic may be behind the U.S., but it will work to keep it that way.
U.S. cases of UK diversity double about every 10 days, new research estimates, with the highest density of cases in Florida and California (dark blue)
On Thursday, there are at least 1,367 cases of various cases in the US.
It has reached almost all states – all but eight – and has taken a firm grip in two states with similar epileptic seizures, but completely different views on the disease. spread: California and Florida.
The variant rose to dominance within a few months of being discovered in the UK in December.
It is thought to be around 70 per cent more contagious and caused a sharp rise in COVID-19 cases in the UK and, as a result, the tightest lockout in the country, which began in early January.
The U.S. has seen a continuous fiv-week turnaround in coronavirus cases, and even daily deaths – which are late on other measures – have begun to decline.
U.S. health officials are relieved that the rise after holidays in diseases, hospitals and deaths is finally slowing.
But they warn that this progress is delicate, and that the swift variables could put it back.
Public health experts have largely been skeptical about what exactly is driving the decline, but Dr. Bedford is not.
‘After a ~ 2 month span from mid-November to mid-January, US # COVID19 infection has gone down steadily week after week and is now back to last-seen daily case accounts at the end of October, ‘he wrote in Twitter on Thursday. thread.
He used daily COVID-19 case numbers in U.S. states and compared them to the Right Honor – or a figure that estimates the rate of transmission based on how many more cases of coronavirus each disease has. follow up.
The transmission rate has gone down – though not without some bumps along the way – in every U.S. state since November, driving down the issues, deaths and ospadalan
The True – or level of transmission – is now below 1 (blue) in almost every state in the US, suggesting that the revolution is ebbing, compared to the November (top left) when the Rt was about one in all states and things were about to go up
When that number is above one, the outlook appears to be growing. When it is at one, the pandemic is considered to be stable, and when Rt falls below one, a revolution is likely to erupt.
The UK has used this figure as an emergency metric to determine if it needs to limit tension or be able to rest.
Dr. Bedford notes that the U.S. was more than 1 in November and December – meaning that each disease caused more than one additional disease, on average.
This led to an explosion of cases, which led to an increase in hospitals and, weeks later, a rising death toll, with more than 5,000 Americans dying from COVID-19 on the deadliest day in the country.
‘In general, Rt> 1 in November and December corresponds to issues rising and falling below 1 in January according to falling issues. We have seen a steady decline in the Rt Hon from November to February. Thus, the current decline is not an abrupt trend in a situation, but came from reaching Rt <1, 'wrote Dr. Bedford.
‘Totally based on continued improvements in seasonality and continued increases in population immunity due to natural and vaccine resistance I would expect this trend to continue largely and for the US to bring fall / winter further under control.
However, the rapid adoption of B117 pushes against these benefits. ‘
In the UK, Denmark and Switzerland the opposite had a growth rate of around 0.7, allowing it to go from a percentage of 20 to 20 per cent of all cases within two and a half months in both countries last, and from 20 per cent to UK leadership.
In the US, the new study – posted as a preview, preceded by a peer review on MedRxiv.com – the researchers from Helix and the Scripps Research Institute thought B117 35 percent to 54 percent more mobile.
That means things are doubling about every 10 days, and the variable seems to have reached the U.S. as early as the end of November.
‘Our study shows that the US is on a similar path to other countries where B.1.1.7 quickly became a major variant of SARS-CoV-2, requiring immediate action to reduce COVID morbidity and mortality -19 reduce, ‘they wrote.
Studies suggest that the variant is not immune to vaccines, but is more mobile and probably about 30 percent more lethal.
Dr. Bedford takes this seriously too, but he has a more optimistic outlook.
‘It is not clear to me at this stage whether a biological increase in B.1.1.7 transmission will “benefit” against further improvements in seasonality and immunity in ~ 6 weeks at the end of March, he wrote.
He said California and Florida are probably the best bellwethers for how B117 will go in the U.S., as they are ‘later’ with 186 and 416 cases of the opposite, respectively.
So far, cases, hospitals and deaths are all declining in both states.
But public health officials will certainly be keeping a close eye in the coming weeks to see if the rapidly spreading variables are changing that.
