Prime Minister Boris Johnson announced earlier this month that Britain would begin the next phase of easing lockdown, including reopening bars, restaurants and hairdressers on July 4.
Sir Jeremy Farrar, director of the London-based research charity the Welcome Trust and a member of the Scientific Advisory Group for Emergencies(SAGE) has revealed he was “worried” that the virus will return following Mr Johnson’s decision.
Mr Farrar estimates that more people will be diagnosed with the virus in the coming weeks.
Sir Jeremy also suggested that Britain faces a “very precarious situation” after examples of large crowds have chosen not to obey the rules.
Speaking to the Andrew Marr show, the SAGE scientist said: “In truth, the restrictions started to be lifted towards the end of May, the beginning of June, around that bank holiday.
“I would predict, I would guess, that we will start to see a few increases in cases towards the end of June or the first week of July.
“We’re on a knife-edge – it’s very precarious, the situation – particularly in England at the moment, and I would anticipate we would see an increase in new cases over the coming weeks.”
Crowds were also seen crammed onto Bournemouth beach last week, whilst Police have been forced to break up illegal raves and parties in the UK.
Sir Jeremy also warned that the public may struggle to distinguish between coronavirus and ordinary fly, suggesting people would have to be extra vigilant if they were sick because of the risk it could be coronavirus.
The Department of Health released the latest figures for the average number of cases in the UK.
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The ONS also revealed the number of positive cases has now “levelled off” following a sharp consistent decrease since May.
Statistics show that the outbreak is not declining in the same way it was before and there’s a risk it could start again.
It is thought that the data could be attributed to the easing of lockdown but scientists still warn if not handled correctly could be the catalyst for a second wave.
The ONS said: “Modelling of the trend over time suggests that the decline in the number of people in England testing positive has levelled off in recent weeks.
These estimates suggest the percentage of testing positive has clearly decreased over time since our first measurement on 26 April, and this downward trend has now flattened.”
But despite statistics suggesting the eve of a new wave, Sir Jeremy believes it is “reasonable” for the Government to continue to ease measures.
He said: “There is no zero risks in any of this.
“We’re not at the stage where the virus has disappeared.
“It remains the same virus.”
Sir Jeremy predicts a second wave could start in October and November.