Newly reported Covid-19 cases in the UK have fallen for the sixth day in a row but the number of patients in hospital with the disease in England has reached its highest level since mid-March, official data shows.

The Government said that as of 9am on Monday, the UK recorded a further 24,950 lab-confirmed Covid-19 cases, down from the 46,558 on July 20.

Dr Mike Tildesley, an infectious diseases expert, said the closure of schools for the summer break was likely to be one of the reasons for falling case numbers, but that it was too soon for data to show any effect from England’s easing of restrictions on July 19.

Meanwhile, the NHS said a total of 5,055 patients were in hospital with Covid-19 in England on Monday, up 33% from the previous week and the highest level since March 18.

The figures reflect the impact of the third wave of coronavirus that began in England at the end of May, but they are still well below levels seen at the peak of the second wave.

Some 34,336 Covid-19 patients were in hospital in England on January 18, the highest number at any point since the pandemic began.

Dr Tildesley, a member of the Scientific Pandemic Influenza Modelling group (Spi-M) advising ministers, said it always takes a couple of weeks for case numbers in the community to be reflected in hospital admissions

He explained that the time lag between infections and hospital admissions means that admissions are likely to continue to rise in the coming days regardless of the number of cases.

Dr Tildesley, from the University of Warwick, said he is “cautiously optimistic” about the drop in cases but only time will tell if the third Covid wave is “turning round”.

He told BBC Radio 4’s Today programme that “any situation where cases are falling clearly is good news”.

But he added: “I think what we need to think about, though, is that there has been a change recently and I think the big one is that, in a lot of parts of the country, schools have now closed for the summer.”

Dr Tildesley explained secondary school children had been completing twice weekly lateral flow tests, adding that “because schools have now broken up, it may be that part of the reason cases have dropped somewhat is that we’re not detecting as many cases in younger people now”.

Education minister Vicky Ford said on Monday that, while the sustained drop in coronavirus cases is “very good news”, people must not become complacent.

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”.

The Government said on Monday that it was expanding its daily contact testing for front line sectors with 1,200 new sites.

A total of 2,000 sites across the country will be available for those working in prisons, waste collection, defence, the food industry, transport, Border Force and police and fire services.

Daily negative lateral flow test results will enable eligible workers who have been alerted by the NHS Covid-19 app or called by NHS Test and Trace as coronavirus contacts to continue working.

Meanwhile, the continuation of US restrictions on international travel has dashed British holidaymakers’ hopes of travelling across the Atlantic this summer.

Current Covid-19-related rules mean most European travellers, including those from the UK, cannot enter the US.

The Associated Press reported that the restrictions will not be lifted due to the prevalence of coronavirus variants in Europe.

Elsewhere, it has been reported that ministers are preparing to ease travel rules for expats returning to the UK from Sunday.

UK nationals living overseas who have been double jabbed will no longer need to self-isolate when they arrive from an amber list country, according to The Daily Telegraph.

The newspaper also reported that ministers are expected to agree to a reciprocal deal on quarantine-free travel with 33 countries, which could lead to a surge in trips between the UK and the EU.

In other developments, Labour leader Sir Keir Starmer has said he backs the “pragmatic” use of Covid vaccine passports, while stressing the importance of testing as part of the certification scheme.

Meanwhile, rail services have seen the introduction of reduced timetables in England after being hit by staff self-isolating.

Workers in the public transport sector are among the thousands of people being pinged by the NHS Covid-19 app.

The Government said that a further 14 people had died within 28 days of testing positive for Covid-19 as of Monday, bringing the UK total to 129,172.

Separate figures published by the Office for National Statistics show there have been 154,000 deaths registered in the UK where Covid-19 was mentioned on the death certificate.