'Long COVID' could surge among young people as the Delta variant continues to push up infection rates, the UK's top doctor warns

• More and more young people could soon become COVID-19 long-haulers, the UK's top doctor warned Tuesday.
• The number of new COVID-19 cases in the UK is doubling roughly every nine days, mostly caused by the Delta variant.
• "I regret to say I think we will get a significant amount more long COVID," Chris Whitty said.

The UK's top doctor has warned that more young people will get 'long COVID' as the Delta variant, which is now responsible for most of cases in the US, pushes up infection rates.

Professor Chris Whitty, England's chief medical officer, said that there was "a lot" of COVID-19 at the moment in the UK, and that infection rates were going up. The UK recorded more than 27,000 new cases on Tuesday - up from 7,724 on June 7.

"I regret to say I think we will get a significant amount more long COVID, particularly in the younger ages where the vaccination rates are currently much lower," he told the Local Government Association's virtual conference on Tuesday, per multiple reports.

"The deaths from Covid I think are mercifully going to be much lower in this wave compared to the previous ones as a proportion of cases but long Covid remains, I think, a worry. We don't know how big an issue it's going to be but I think we should assume it's not going to be trivial," he said.

One in three people who get symptomatic COVID-19 develop long COVID, defined as at least one self-reported symptom lasting for more than 12 weeks, UK data from June suggested. The authors of the study, from Imperial College London, estimated that at least 2 million Brits were COVID-19 long haulers.

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More than 95% of new infections in the UK are caused by the highly infectious Delta variant, which now accounts for more than half of all US cases, according to the Centers for Disease Control and Prevention.

Whitty said that keeping infection rates low and ensuring everyone was vaccinated would prevent long COVID. "I think we really just need to push hell for leather for those two," he said.

Patrick Vallance, chief scientific advisor to the UK government, said in a press conference Monday that the number of new infections in the UK was doubling roughly every nine days.

UK Prime Minister Boris Johson said in the same press conference that the UK could hit 50,000 new cases per day by the time the country's coronavirus restrictions ease on July 19.

Whitty said in Monday's press conference that it wasn't clear yet if vaccination "weakened or broke" the link between catching coronavirus and developing long COVID.

But there was a "reasonable expectation" that vaccines reduce the risk , he said, based on the fact vaccines prevent severe disease, and that people who get hospital treatment are more likely to experience long-lasting symptoms than those who didn't, per Imperial College study found.

Data on this will come out in the next few months, Whitty said.

Roughly 64% of Brits are fully vaccinated, according to government statistics. In the US, 47.5% of people are fully vaccinated, according to the CDC.