Director of public health Greg Fell said flu was difficult to predict but was causing concern for a number of reasons.
He told a scrutiny meeting: “Last winter, there was almost no flu and that was unheard of.
“We were all wearing face masks and washing hands regularly. We had really high rates of vaccination and it was a good match with the virus to vaccine.
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“This year there’s less residual immunity and some queries about the severity of the strain. We don’t know about the virus to vaccine match and we won’t know until we come into contact with flu.
“The general sense from virologists and others making predictions is that it could be a bad flu year that significantly exacerbates the position that the NHS and social care is in.”
Covid is part of the pressure but there is also a wave of respiratory infections with GPs, ambulances and A&E departments seeing record numbers of patients.
Added to that, a home care crisis means more than 200 patients due to be discharged are having to remain in hospital which means fewer beds are available.
‘There are no easy fixes’ warns director of public health Greg Fell
Mr Fell added: “What you see in the media both locally and nationally is definitely true. We have the depths of a bad flu winter type pressure in mid to late November.
“Winter will be exceptionally difficult for the health and social care system, not just the hospitals. That matters for all sorts of reasons but most importantly because the care of other people may get delayed.
“There is a big pressure on hospitals to deal with the elective care backlog from the pandemic and that’s going to be exceptionally difficult for the hospitals in a time of very high pressure.
“There are no easy fixes, all parts of the NHS and social care system are working exceptionally hard to provide care for those who are acutely ill with Covid or other respiratory viruses.”
Mr Fell is encouraging everyone to have a flu jab this year.