The Omicron coronavirus variant is spreading far faster across the US than health officials had expected, accounting for almost three-quarters of new cases, according to data from the Centers for Disease Control and Prevention.
The CDC on Monday released its latest figures for the proportion of infections caused by Omicron, estimating that the variant now makes up 73 per cent of cases – up from 13 per cent in the previous week.
The rate of spread of the new strain has far outpaced officials' expectations. Just three days ago, Rochelle Walensky, CDC director, said she expected Omicron to become the dominant strain "in the coming weeks", while one administration official told Politico last week they expected it to do so "within four weeks".
The CDC did not comment on the latest figures, which are calculated by conducting genomic sequencing on a sample of positive tests from across the country.
President Joe Biden said in a tweet on Monday night that Omicron cases were on the rise. He added: “If you’re an adult choosing to be unvaccinated, you will face an extremely difficult winter for your family and community.”
Since the first US case of Omicron was confirmed in California on December 1st, the strain has been identified in all but four states, according to the CDC.
Outbreaks have prompted cities and states to reinstate pandemic restrictions such as indoor mask mandates in an effort to slow the wave of infections.
Several Broadway shows including the hit musical Hamilton have postponed performances, while many New York restaurants have shut temporarily after workers tested positive for the virus.
On Tuesday Mr Biden will announce further measures to tackle the spread of the virus, but he has so far resisted calling for states to impose the kind of restrictions being imposed in parts of Europe, where the Netherlands has just entered another lockdown.
The seven-day average number of daily infections in the US has doubled since late October. Adjusted for population, at about 40 per 100,000 people, it is only a third of that in the UK.
Hospitalisations and deaths in the US have so far remained relatively steady, though officials expect all metrics to worsen rapidly as people travel to see friends and family over Christmas and New Year.
Cases have risen particularly quickly in US states experiencing colder weather, such as those in the north-east.
New York governor Kathy Hochul said on Monday that 23,391 residents had tested positive for Covid-19 on Sunday, marking the fourth consecutive day the state has set a pandemic-era record for new infections.
In the Houston, Texas area on Monday, Lina Hidalgo, Harris county judge, said at a press conference that she had been informed of the area's first Omicron-related death".
Judge Hidalgo, who earlier on Monday raised the Covid threat level in Harris county to its second-highest setting, said the deceased individual was a man in his fifties who was not vaccinated. She urged residents of the county to get vaccinated and take necessary health precautions. – Copyright The Financial Times Limited 2021