A SECOND wave of Covid-19 infections could be more serious than the first, with 120,000 hospital deaths in a "reasonable worst-case scenario", scientists advising the UK Government warned in a new report.

The report from the Academy of Medical Sciences, commissioned by the UK Government's chief scientific adviser Sir Patrick Vallance, says action needs to be taken now to mitigate the potential for a second peak of coronavirus.

The report argues hospitals could see 120,000 Covid-19 deaths between September and next June at the same time as they battle a surge in demand due to usual winter pressures, including flu.

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The report, from 37 scientists and academics, acknowledges there is a high degree of uncertainty about how the Covid-19 epidemic will evolve over the coming months, but sets out a "reasonable worst-case scenario" that would see the R rate rise to 1.7 from September.

The R refers to the number of people an infected person can be expected to pass the virus on to.

The academic modelling suggests there could be a peak in hospital admissions and deaths in January and February 2021, similar to or worse than the first wave in spring 2020. It does not include deaths in the community or care homes.

The figures do not take account of the UK Government intervention to reduce the transmission rate, or the use of the drug dexamethasone in intensive care units, which has been shown to cut deaths.

Professor Stephen Holgate, a Medical Research Council clinical professor of immunopharmacology who led the study, said: "This is not a prediction, but it is a possibility.

"The modelling suggests that deaths could be higher with a new wave of Covid-19 this winter, but the risk of this happening could be reduced if we take action immediately.

"With relatively low numbers of Covid-19 cases at the moment, this is a critical window of opportunity to help us prepare for the worst that winter can throw at us."

He said action that was needed before winter sets in included flu vaccination for the vulnerable and health and social care workers.

England's NHS Test and Trace must be "upscaled in the winter", he added, saying more people will need to be tested as winter illnesses can often have similar symptoms to Covid-19.

He also called for a "rapid system of monitoring" across the UK to stop local outbreaks when they occur.

The team also looked at less serious scenarios of what may happen, with an R rate of 1.1 leading to 1300 hospital deaths between September and June.

They also modelled an R of 1.5, which would lead to 74,800 hospital deaths.

Prof Azra Ghani, chairwoman in infectious disease epidemiology at Imperial College London - who worked on the study, said many things could push the R up to 1.7.

She told the PA news agency: "We are looking at what would be the worst that would happen, such as if there was a further relaxing of interventions, more contacts taking place, schools may be a factor, people going back to work and that sort of thing.

"Those things create more contacts, plus people will be indoors more and more people will want to meet up indoors."

She said the virus was known to spread more easily indoors "and, of course, during the winter, we spend far more time indoors than we do during the summer".

She added: "In addition, we're less likely to have our windows open, doors tend to be closed to keep out the cold, and that will again enhance transmission.

"It's also possible that the virus itself could survive for longer in colder conditions."

Dame Anne Johnson, professor of infectious disease epidemiology at University College London and vice president of the Academy of Medical Sciences, said there was a need for a "powerful public information campaign" in the run up to winter.

"Everybody needs to realise that Covid-19 hasn't gone away, and therefore everybody can help reduce transmission by social distancing, by the wearing of face coverings as a social norm, by good respiratory and hand hygiene and the right level of heating and ventilation in our homes," she said.

A UK Government spokesman said: "The modelling in this report represents a worst-case scenario based on no government action, and makes clear this isn't a prediction.

"Thanks to the nation's collective efforts, the virus is being brought under control. However we remain vigilant and the Government will ensure the necessary resources are in place to avoid a second peak that would overwhelm our NHS."