The latest on the coronavirus pandemic and the Omicron variant

The United States could face a surge of Covid-19 cases this January, with the Omicron variant possibly contributing to that winter wave, according to modeling data that was presented to state and local health officials during a call with the US Centers for Disease Control and Prevention on Tuesday. But that's just one possible scenario.

The modeling information, along with data from Europe, indicates that the number of Covid-19 cases caused by the Omicron variant has the potential to double every two days, Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials, told CNN on Wednesday.

The CDC told CNN in a written statement Tuesday that the agency "regularly discusses planning scenarios with public health officials around the country" and Tuesday's discussion "was part of a regularly scheduled meeting hosted by the CDC COVID-19 Response with the leaders of four public health organizations." 

The statement noted that the CDC is "preparing for a range of scenarios" with the Omicron variant and a portion of Tuesday's meeting was dedicated to "discussion around results from various modeling groups related to Omicron" — but no CDC, US Department of Health and Human Services or US government models were presented.

"That modeling implies that sometime in January, we will be at a different stage of recognizing Omicron, maybe as even a predominant virus. However, we still are learning about the severity, transmissibility," Freeman said. "The data is emerging from around the world." 

While the Delta variant continues to cause the most Covid-19 cases in the United States, Omicron climbed from causing 0.4% of cases in the week ending on Dec. 4 to causing 2.9% of cases in the week ending on Dec. 11, according to CDC data. Currently, CDC data indicates that Delta causes 96.8% of cases.

Freeman said that there is concern a rise in Omicron cases paired with climbing Delta cases and an increase in flu cases potentially could overwhelm health systems this winter as well as possibly lead to a need to ramp up Covid-19 testing capacities.

"We don't want to overwhelm systems more," Freeman added. "But it looks like that we need to prepare for that because if this virus spreads that rapidly, even though it doesn't make people that sick, they're going to seek testing."

After a week of predicted stable or uncertain trends, an ensemble forecast from the US Centers for Disease Control and Prevention published Wednesday predicts an increase in newly reported Covid-19 deaths over the next four weeks. 

Before last week, deaths had been predicted to increase for the two prior weeks. 

The previous forecast, published Dec. 8, predicted up to 837,000 Covid-19 deaths reported by Jan. 1. 

According to data from Johns Hopkins University, there have been 800,473 Covid-19 deaths in the United States. 

For the fourth week, the hospitalizations forecast predicts an increase over the next four weeks, with 6,300 to 18,400 new confirmed Covid-19 hospital admissions reported on Jan. 7, 2022. 

According to US Department of Health and Human Services data, there were 67,306 people hospitalized with Covid-19 on Dec. 14. 

The forecast for cases did not predict an increase or decrease.

“More reported cases than expected have fallen outside the forecast prediction intervals for three- and four-week ahead case forecasts. Case forecasts at those horizons and assessments of likely increases or decreases will not be shown until sustained improvements in performance are observed,” according to the CDC.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, and other members of the White House Covid-19 task force are providing an update on Omicron and vaccine efficacy against the coronavirus variant.

Fauci, who also serves as President Biden's chief medical adviser, told CNN last week that the NIH lab was expecting to have results early this week on vaccine efficacy against Omicron. 

 He called this a “very strong argument” for people to get boosters. 

“Omicron is going to be a challenge because it spreads very rapidly and the vaccines that we use, the regular two-dose mRNA, don’t do very well against infection itself,” he said. “But with hospitalization, particularly if you get the boost, it’s pretty good.” 

CNN's Naomi Thomas contributed reporting to this post.

The United Kingdom on Wednesday reported 78,610 new cases of Covid-19, according to government data, which is the highest number of daily cases since the pandemic began.

The previous record of daily new infections was on Jan. 8, with 68,053 cases.

Prime Minster Boris Johnson is expected to hold a news conference at 12 p.m. ET from Downing Street.

Africa might not attain 70% vaccination against Covid-19 until August 2024, according to World Health Organization Regional Director for Africa Dr. Matshidiso Moeti.

“We are entering the year-end holiday season of traditional gatherings and travel, with vaccine coverage still disappointingly low in Africa,” Moeti said at a news conference on Tuesday.

“If things continue like this, Africa may not reach the 70% vaccination coverage target until August 2024. Just six countries have hit the year-end target of fully vaccinating 40% of their citizens, with only 20 managing to achieve 10% coverage,” she said.

In September, US Secretary of State Antony Blinken announced the United States’ support for WHO’s goal of 70% vaccination of the world population by 2022.

Moeti said travel bans related to the Omicron variant “compound” the problem in Africa.

“Travel bans can lead to less money for food, medicine, education and a host of services that keep people healthy, consequently jeopardizing the welfare of millions of Africans. They can also affect supplies of critical items for health and other development areas,” she said, noting that Africa’s share of Omicron cases is “steadily dropping.”

“I would like to appeal to countries to urgently reconsider the recently introduced travel bans. This is a time to instead show solidarity with your neighbors, and to act in the interests of the global good.”

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said on Tuesday that new National Institutes of Health data about vaccine efficacy against the Omicron coronavirus variant will be discussed today, and it mostly confirms findings from other countries. 

“It mostly confirms what you have been hearing that [has] come from South Africa as well as the UK," Fauci said to CNN yesterday when asked about the new data.

The White House Covid-19 response task force is set to hold a news conference at 11 a.m. ET today.  

Last week, Fauci told CNN that the NIH lab was expecting to have results early this week on vaccine efficacy against Omicron. 

 He called this a “very strong argument” for people to get boosters. 

“Omicron is going to be a challenge because it spreads very rapidly and the vaccines that we use, the regular two-dose mRNA, don’t do very well against infection itself,” he said. “But with hospitalization, particularly if you get the boost, it’s pretty good.” 

The European Centre for Disease Prevention and Control said on Wednesday that vaccinations alone will not stop the spread of the Omicron variant, adding that “strong action” was urgently needed to reduce its transmission. 

“In the current situation, vaccination alone will not allow us to prevent the impact of the Omicron variant, because there will be no time to address the vaccination gaps that still exist,” Dr. Andrea Ammon, director of the ECDC, said in a statement.

Ammon also said that “countries should ramp up efforts to increase full vaccination in people not yet vaccinated or only partially vaccinated, as well as to administer booster doses to all eligible as soon as possible.”

“It remains a priority to use face masks appropriately, telework, prevent crowding in public spaces, reduce crowding on public transport, stay home when ill, maintain hand and respiratory hygiene measures and ensure adequate ventilation in closed spaces,” the ECDC statement concluded.

ECDC raised its risk assessment for Omicron's impact on public health to “very high” on Wednesday, adding that Omicron would “probably become dominant in early 2022, based on mathematical modelling predictions.”

The Omicron coronavirus variant is “probably the most significant threat” seen since the start of the pandemic, a UK health chief said. 

Dr. Jenny Harries, chief executive of the UK Health Security Agency, warned the government’s Transport Select Committee on Wednesday that case numbers will be “quite staggering compared to the rate of growth that we’ve seen in cases of previous variants.” 

“The real potential risk here – and I would underline that because we are still learning a lot about the variant – is in relation to its severity, clinical severity, and therefore whether those cases turn into severe disease, hospitalizations and deaths,” Harries said. 

“We’re still at too early a stage for that, in fact the world probably is still at too early stage to be clear,” she added. 

“When it started we were estimating about four or five,” she said.  

Harries added Omicron “could have a very significant impact on our health services.” 

The Omicron variant may not necessarily be super-transmissible but may be taking over in some countries because of waning transmission of the Delta variant, a biostatistician who has been carefully monitoring the spread of coronavirus said Tuesday. 

“You can actually look and see on the ground, how many people do [you] think one person's infecting, one infected person is spreading to. And if you look at Omicron, that is perhaps three times faster than Delta. That is what's coming up in South Africa,” said Trevor Bedford, an associate professor in the Vaccines and Infectious Disease Division with the Fred Hutchinson Cancer Center in Seattle.

“That doesn't mean it's three times as transmissible as Delta,” Bedford told Andy Slavitt, former President Biden senior adviser on Covid-19, on Slavitt’s podcast.

“What I think is mostly going on is that Delta had a decreasing fraction of people that it was able to infect — where it was kind of people who were not vaccinated who are not infected, or people who've had enough waning immunity that they're now available again to the virus,” Bedford added. “Whereas Omicron, by having such a different spike protein, has this whole susceptible pool of people available to it, so it can infect three times as many people.”

Bedford said it is not a foregone conclusion that Omicron will eventually overtake Delta as the dominant variant in the US. The virus could behave more like the flu virus, where multiple lineages circulate at the same time.

“It's possible, but not definite that that's what we'd see with Omicron versus Delta-like viruses, that it won't be that Omicron displaces Delta. It'll be that in two years’ time. They'll both be kind of continuing to coexist because they're different enough,” he said.

“It also could be that they're not quite different enough and that we still see like a wave and then Delta eventually displaces Omicron or Omicron displaces Delta. We don't know yet. But those are the three scenarios — either only Delta, only Omicron, or both coexisting in two years’ time.”