Britain should prepare itself for a "hard winter" with the threat of Covid-19 and a flu surge still a possibility, a Public Health England official has said. The NHS will have to be ready for a potential rise in respiratory viruses as people wait to discover if there is a strong level of immunity in the population, according to Dr Susan Hopkins, who advises the Government on its Covid policy. Dr Hopkins, who is Covid-19 strategic response director to Public Health England, told the BBC's Andrew Marr Show: "I think we have to prepare for a hard winter, not only with coronavirus but we've had a year of almost no respiratory viruses of any other type, and that means potentially the population immunity to that is less, and so we could see surges in flu. "We could surges in other respiratory viruses and other respiratory pathogens." Dr Hopkins added: "So it's really important that we're prepared from the NHS point of view, from public health and contact tracing, that we have everything ready to prepare for a difficult autumn, and we hope that it won't occur and there will be a normal winter for all of us." Dr Hopkins said she believed "we will all have our summer holidays" but her job is to advise the Government and to prepare for "worst-case scenarios". She told the programme: "We have to make sure that we're prepared, and that we're better prepared for this autumn than we have been previously." Despite her warnings for next year, Dr Hopkins said the emergence of new variants of the coronavirus should not derail a plan to start easing a nationwide lockdown in England over the coming weeks. "I think it won't change it for the next three to five weeks, that would be highly unlikely," Dr Hopkins, PHE’s strategic response director, told the BBC's Andrew Marr show. "We will need to watch it carefully as new strains come into the country from around the world and we will need to be very ready for autumn."