Britons have been advised to practice hand hygiene measures after norovirus, known as the 'winter vomiting bug', forced a number of hospitals across the country to close wards to new admissions.
New patients were not being admitted to wards at Doncaster Royal Infirmary and Montagu hospital in South Yorkshire in a bid to stop the spread of the seasonal illness.
Maurice Madeo, deputy director of infection prevention and control at Doncaster Royal Infirmary, told the Press Association: 'We can't be too careful about limiting the spread of all infections.
'An infection on top of another medical condition can prove fatal to sick, frail patients. So we all need to be mindful of the need for best practice in personal hygiene.'
Norovirus is highly contagious and affects between 600,000 and one million people in the UK each year.
Symptoms include a sudden sick feeling followed by vomiting and diarrhoea, which may be accompanied by a raised temperature, headaches, stomach cramps and aching limbs.
Symptoms usually disappear within a couple of days.