Initial data suggests that the Omicron variant of COVID is less severe, saying that sufferers are 50 percent to 70 percent less likely to need hospitalization than those with the Delta variant, the U.K. Health Security Agency said Thursday. They also said Omicron variant-infected people are estimated to be 31 percent to 45 percent less likely to go to a hospital emergency department than those with the Delta variant.

However, the agency warned the findings are “preliminary and highly uncertain” due to the small amount of Omicron patients in hospitals and the fact that a majority of them are younger. The 14 patients who have died were between the ages of 52 and 96.

Scientists also said any decrease in the severity of infection needs to be considered against the speed of infection of the Omicron variant versus the Delta variant, as well as the fact that Omicron can better evade vaccines.

Omicron is the dominant strain in Britain currently, with cases having increased over 50 percent in a week. On Thursday, Britain had 119,789 reported cases of COVID, the highest number in the pandemic and the second day the number has surpassed 100,000.

The agency’s research said the protection a booster shot of vaccine gives against symptomatic Omicron infection appears to wane after about 10 weeks, though protection against hospitalization and severe disease is likely to hold up for longer.

UKHSA chief executive Jenny Harries said the analysis “shows an encouraging early signal that people who contract the Omicron variant may be at a relatively lower risk of hospitalization than those who contract other variants.”

But she added that “cases are currently very high in the U.K., and even a relatively low proportion requiring hospitalization could result in a significant number of people becoming seriously ill.”

U.K. Health Secretary Sajid Javid said the emerging information about Omicron was “encouraging news,” But he said it was “not very clear yet … by how much that risk is reduced” compared to delta.

The analysis follows two studies, from Imperial College London and Scottish researchers, that found patients with Omicron were between 20 percent and 68 percent less likely to require hospital treatment than those with delta.

Data out of South Africa, where the variant was first detected, have also suggested Omicron might be milder there.

Even if the early studies are borne out, the new variant could still overwhelm health systems because of the sheer number of infections. The British health agency said Omicron appeared able to re-infect people more easily than previous variants, with 9.5 percent of Omicron cases found in people who had already had COVID-19—a figure it said was likely an underestimate.

Britain’s Office for National Statistics estimated that about 1 in 45 people in private households in England—1.2 million individuals—had COVID-19 in the week to December 16, the highest level seen in the pandemic.

Britain’s Conservative government this month reinstated rules requiring face masks in shops and ordered people to show proof of vaccination or a negative coronavirus test before entering nightclubs and other crowded venues in an attempt to slow Omicron’s spread.

The government said Thursday it would not impose any new restrictions before Christmas, but might do so soon after.

Officials also urged people to get tested regularly and cut back on socializing. Many in Britain have heeded that advice, leaving entertainment and hospitality businesses reeling at what should be their busiest time of the year.

The government has offered grants and loans to support restaurants, bars, theaters, and other venues, but many say it is not enough to stop them going under.

Rules set by the U.K. government apply in England. Other parts of the U.K.—Scotland, Wales, and Northern Ireland—have set slightly tighter restrictions, including the closure of nightclubs.

The government is hoping vaccine boosters will provide a bulwark against Omicron, as the data suggests, and has set a goal of offering everyone 18 and up a third shot by the end of December.

The Associated Press contributed to this report.