More than 800 people had been waiting a year or more for routine treatments at Epsom and St Helier hospitals in February after record backlogs during the coronavirus outbreak.
The Nuffield Trust revealed the record size of the NHS waiting list across England shows the health service has been set back years by the coronavirus pandemic and now faces a "major backlog".
NHS rules state that patients referred for non-urgent consultant-led elective care should start treatment within 18 weeks.
But NHS statistics show 880 patients listed for elective operations or treatment at Epsom and St Helier Trust at the end of February had been waiting for at least a year – 3% of all those on the waiting list.
This was a huge increase from one the year before, and the highest figure for the month of February since comparable records began in 2012.
The number of people waiting this long across England has risen to 387,900 – the highest total since December 2007, and almost 250 times that of February 2020.
The Nuffield Trust said the strain of the backlog on patients should not be underestimated, but added it is no surprise given the intense pressure of Covid-19 hospitalisations.
Sarah Scobie, deputy director of research at the organisation, said healthcare staff have made huge sacrifices during the pandemic, but more will be asked of them.
She added: “It is clear that the NHS has been set back years as it faces a battle to clear these major backlogs of postponed care.
"Returning to the levels of activity seen before March last year will not be enough to meet demand, and we will continue to live with coronavirus for years to come."
Overall, 28,837 people were waiting to start hospital treatment at Epsom and St Helier University Hospitals Trust at the end of February – an increase of 2% on January.
Across England, 4.7 million people were waiting for treatment at this time – the highest number since records began in mid-2007.
This was up from 4.6 million in January, and means almost half a million patients have been added to the waiting list since the pandemic began in March 2020.
David Maguire, senior analyst at the think-tank, said: "The Government needs to be honest with the public and start planning for long-term NHS recovery.
A good place to start would be with a fully funded workforce strategy to address the persistent staff shortages that have dogged the service for years."
Prime Minister Boris Johnson said the Government will ensure the NHS has the funds it needs to tackle the build-up in waiting lists.
Have you been affected by the coronavirus pandemic? Contact us at monica.charsley@newsquest.co.uk
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