Health Secretary Sajid Javid has said “no one really knows” how many COVID-19 cases there might be during the rest of the summer as he failed to stick to his previous prediction of 100,000 daily infections.

According to government figures, there were more than 54,000 COVID cases reported on 17 July – the current highest number of daily infections during the UK’s third wave of cases – which came before the removal of almost all coronavirus restrictions in England two days later.

The soaring number of cases prompted concerns that businesses and transport networks could grind to a halt as huge numbers of people were asked to self-isolate as a result of the pingdemic.

However, there has since been seven consecutive days of falls in the number of new infections – although daily cases in the UK rose once more to 27,734 on Wednesday.

Asked whether he believed, following the week-long fall in the number of new infections, whether the country was now through the worst of the pandemic, Mr Javid said the public needed to “remain vigilant”.

He also declined to repeat his previous prediction, made at the beginning of the month, that there could be as many as 100,000 daily cases this summer.

“The truth is, I think, that no one really knows where cases will eventually end up,” the health secretary said on a visit to a pop-up vaccination centre in London’s Little Venice.

“We’ve seen sadly, throughout this pandemic, over the last 18 months, case numbers go up and down.

“We know the latest increase we saw was because of this variant – at the time we called it a new variant, now it is the variant, the Delta variant and it is hugely infectious.

“So that’s why we’ve got to remain vigilant and one of the things we spend a huge amount of time on is looking out for new potential variants.

“Especially those that might have properties of escaping the current vaccines.”

Mr Javid said it was “encouraging” to see the number of daily cases fall in recent days, but he added it was “too early to take a long-term trend from that” and stressed the pandemic was “of course” not over.

“There is still a lot of the virus around, unfortunately, so we have to remain cautious and vigilant,” he said.

The health secretary urged around three million people between the ages of 18 to 29 who have not yet had a first COVID vaccine dose to get a jab.

“They should really come forward and not just protect themselves, help protect their loved ones, do their bit for the community,” he said.

“We’re in a race against this horrible virus and older adults have done their bit and got out there in this race and helped us start winning in that race.

“But we need younger people – we’ve passed the baton to them, and we’re saying ‘please help get us over the line, get vaccinated and let’s get this done’.”

Mr Javid added the “wall of defence” provided by COVID vaccinations had so far prevented 11 million infections, stopped 57,000 people from going to hospital, and avoided 37,000 new coronavirus-related deaths.

The recent fall in the number of COVID cases being reported has left experts split over the possible cause of the downturn.

Some have attributed the start of the school holidays, an increase in the number of people self-isolating, recent warmer weather, the end of the Euro 2020 football tournament, high levels of vaccination or natural immunity from previous infection, or a mixture of all those factors.