The worst of the pandemic could be behind us by late September, an expert has said, as the number of Covid-19 cases in the UK continued to fall.

Professor Neil Ferguson – whose modelling led to the first lockdown in March 2020 – said caution is still needed, but offered a hopeful outlook for autumn.

His comments come as health leaders warned the NHS is as stretched now as it was at the height of the pandemic in January, and things will get worse before they get better.

I’m positive that by late September or October time we will be looking back at most of the pandemic.

It will be “several more weeks” before the effect of the July 19 unlocking in England is known, said Prof Ferguson, from Imperial College London, and a member of the Scientific Advisory Group for Emergencies (Sage).

He told BBC Radio Four’s Today programme: “We need to remain cautious, especially with the potential increase in contact rates again as the weather becomes less fine and schools return.

“We’re not completely out of the woods, but the equation has fundamentally changed. The effect of vaccines is hugely reducing the risk of hospitalisations and death.

“And I’m positive that by late September or October time we will be looking back at most of the pandemic.

“We will have Covid with us, we will still have people dying from Covid, but we’ll have put the bulk of the pandemic behind us.”

NHS Providers, which represents hospital trusts, has written to Prime Minister Boris Johnson, Chancellor Rishi Sunak, Health Secretary Sajid Javid, Chief Secretary to the Treasury Steve Barclay, and NHS England chief executive Sir Simon Stevens, to say a combination of pressures were being experienced by the health service.

It called on ministers to make “the right decisions” over the next month as it finalises NHS funding for the second half of the financial year.

Official figures on Monday showed the number of Covid-19 cases newly reported in the UK dropped for the sixth day in a row, but according to NHS data there has been a rise in hospital admissions in England.

A total of 5,055 patients were in hospital with Covid-19 in England on Monday.

This is up 33% from the previous week and the highest since March 18, but still well below levels seen in the second wave of the pandemic.

A Number 10 spokesman said the fall in coronavirus cases was “encouraging” but numbers were still expected to rise, adding that “the Prime Minister thinks we’re not out of the woods yet”.

More than half of Covid hospital admissions are patients who only tested positive later, the Daily Telegraph reported, citing leaked data.

The newspaper said the leaked data for English NHS trusts showed that as of Thursday, just 44% of patients classed as being in hospital with Covid had tested positive when they were admitted.

A total of 218 deaths registered in England and Wales in the week ending July 16 mentioned Covid-19 on the death certificate, according to the Office for National Statistics (ONS) – up 19% on the previous week.

It is the highest total since 260 deaths in the week to April 23.

The total number of deaths with Covid in the UK has now reached 154,661, the ONS said.

Meanwhile, the continuation of US restrictions on international travel has dashed British holidaymakers’ hopes of travelling across the Atlantic this summer, with policing minister Kit Malthouse describing the decision by the American Government not to loosen its rules as “disappointing”, but not surprising.

He told Sky News: “Obviously that is for them to assess and we are assessing the likelihood of variants coming in from other countries as well. So, it doesn’t surprise me that they are doing similar. It is obviously disappointing.”