Covid-19 hospital admission rates for people aged 75 and over in England have jumped to their highest level for more than a year, figures show.
New cases of the virus are also estimated to be increasing among all age groups in all regions, with health chiefs warning numbers are likely to rise further.
Admission rates for hospital patients with Covid-19 in England in both of the oldest age groups, 75 to 84-year-olds and people 85 and over, are now at their highest since mid-January 2021, when the second wave of the virus was at its peak.
The rate for over-85s stood at 178.3 per 100,000 people last week, up from 137.0 the previous week, while for people aged 75 to 84 it was 74.3, up from 59.8.
Rates among other age groups were lower, though all showed a week-on-week increase, according to the UK Health Security Agency (HSA).
The overall Covid-19 hospital admission rate in England stood at 17.9 per 100,000, up from 14.1 and the highest since the week to January 16, 2022.
Dr Susan Hopkins, HSA chief medical adviser, said the figures are “a reminder to us all that the pandemic is not over”.
She added: “Hospital admissions and cases of Covid-19 have continued to rise and we can expect to see further increases before we start to see a decline.
“Vaccination is the key to staying safe from serious illness and it’s vital that everyone gets all of their recommended doses.
“Wearing a face covering in crowded or enclosed spaces, socialising outside where possible, and always observing good hand hygiene will also help to reduce the spread of Covid-19.
“Anyone with symptoms or a positive test should limit their contact with others as much as possible.”
Case rates among people aged 50 and over are estimated by the HSA to have climbed back to levels last seen in early January this year, at the peak of the wave caused by the original Omicron variant.
The current surge in infections is being driven by the Omicron BA.2 variant – a more transmissible form of the virus.
But other factors might be contributing to the trend, including “the gradual increase in social contacts over recent weeks and the ending of legal requirements for self-isolation”, the HSA said.
Rates for younger age groups are also increasing and are estimated to be at levels last recorded in early February.
A total of 13,602 people with Covid-19 were in hospital in England as of 8am on March 24, up 20% week-on-week and the highest number since January 27, according to NHS England.
But two regions – south-west and south-east England – are now recording patient levels last seen in February 2021, surpassing the peaks reached in the Omicron wave at the start of this year.
A third region, eastern England, is close to overtaking its Omicron peak.
Separate data published on Thursday by NHS England shows just over half of all Covid-19 patients in hospital trusts in England (55%) are being treated primarily for something else, a figure that is broadly unchanged on the last few weeks.
All patients who have tested positive for Covid-19 need to be treated separately from those who do not have the virus, regardless of whether they are in hospital primarily for Covid or not.
But the proportion of patients who are in hospital “with” Covid-19 rather than “for” it continues to be much higher than it was for most of last year, when the figure stood at around 25%.