The UK’s health watchdog has issued a warning that cases of the vomiting bug norovirus are surging this winter.
The UK Health and Security Agency (UKHSA) said cases are rising the most quickly in over-65s, and have urged the public to practice good personal hygiene.
Norovirus, commonly known as the winter vomiting bug, is a virus that causes sickness and diarrhoea.
Other symptoms include a headache, aching arms and legs, and a high temperature.
“Norovirus cases are rising and lab reports are currently about 1/3 higher than what we would see at this time of year,” the UKHSA said on Thursday.
“Rates have increased most in those 65 and over, however, we haven't seen an increase in care home outbreaks.
"Protecting yourself against norovirus is key and can be done in many simple ways.
"Practicing good hand hygiene like washing your hands after using the toilet or after an episode of illness and before eating for preparing food is a great way to avoid getting ill."
The data shows that the number of cases in the final week of 2022 and the first week of 2023 were 34% higher compared to the same two-week period in the five years prior to COVID.
The watchdog also say the majority of outbreaks were reported in care home settings.
Dr Tim Cooksley, president of the Society for Acute Medicine, told MailOnline that rising cases will "exacerbate" the pressure on the NHS as multiple trusts declare critical incidents due to winter pressures.
"The NHS continues to be under significant strain and things remain finely balanced as we try to manage the levels of pressure colleagues are facing and prepare for further difficult winter months ahead," he said.
"Increases in cases of norovirus will exacerbate problems in the whole health and social care system considering the impact this has when it makes its way into hospitals."
He added: "This involves bed closures, infection among seriously unwell people and staff absence, so it is very worrying to see any increase in cases of the virus given the fragile state of play."
The rise in norovirus cases comes after the NHS has already been struggling with a worse than average flu season, combined with the fallout from COVID.
Dr Stephen Powis, NHS national director, earlier this month urged the public to make sure they have had their flu jabs if they are eligible.
"We knew this winter would be one of the most difficult in the history of the NHS and I want to thank staff for all their hard work in caring for and treating so many patients while dealing with record demand on services, including the enormous pressure from flu and COVID," he said.
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