The number of people in hospital with COVID-19 is increasing significantly, it has been warned, with one hospital suspending visitors “due to health and safety concerns”.

Dr Chaand Nagpaul, chairman of the council at the British Medical Association, told Sky News: “What’s concerning is that we are seeing significant increases in people in hospital.

“In fact, as of yesterday, the number of people admitted and also the number of patients in hospital is at a level as high as during the lockdown earlier this year in spring, in February-March.

“Now that is a significant number and it is increasing, so while the proportion of people who end up in hospital as a result of Omicron is smaller, we are definitely seeing significant increases.”

Dr Nagpaul said 25,000 patients were admitted with COVID-19 in the four-week period leading up to Christmas and he said those admissions have been preventing six million people on the NHS waiting list from being treated.

Asked whether those admissions were people taken to hospital because of coronavirus, or for other health reasons and “happened to have COVID”, Dr Nagpaul replied: “That’s a very good question and, in fact, that’s data I don’t have and data it is really important is made available, because I absolutely agree, we need to differentiate between the two.”

Fresh NHS figures on hospitalisations in England are due to be published today.

It comes as Northampton General Hospital tweeted: “The health, wellbeing and safety of all our people, including patients and colleagues continues to be our top priority. We have therefore taken the difficult decision to suspend visiting at the hospital from today, Friday 31 December.”

As the UK gears up for New Year celebrations tonight, with parties allowed in England, but restrictions on gatherings in both Wales and Scotland, accessing lateral flow and PCR tests continues to be difficult.

A shortage of lateral flow tests means those wishing to mix with others at nightclubs, pubs and house parties face doing so without knowing if they are COVID positive.

Lateral flow tests are available to order on the government portal, but could take days to arrive and Health Secretary Sajid Javid yesterday warned that supplies may need to be “constrained” further because of demand.

PCR tests are available to book on the government’s website, but results usually take around 24 hours.

A leading scientist has urged people to take care, warning that the Omicron variant “has ended up being so infectious that it almost needs just a whiff of infected breath and you could get infected”.

Professor Peter Openshaw, who sits on the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG), told the BBC: “We’re lucky really that it wasn’t this infectious when it first moved into human-to-human transmission.”

And the head of NHS Providers has warned that even if the government brings in extra restrictions in England, it will take two weeks to reduce the hospital admission rate.

As eight hospital trusts set up new Nightingale “surge hubs” in preparation for an influx of COVID patients, Chris Hopson told Radio 4’s Today programme that “we still don’t know if a surge will come, and indeed we are exactly talking about the preparations we are making for that surge right now”.

He added: “It is worth remembering that it does take about a fortnight for any new restrictions to affect the level of hospital admissions, so the pattern of hospital admissions for the next fortnight has already been set.”