TEN more people have died from confirmed flu taking the death toll to 27, according to the latest UK figures.
The Health Protection Agency (HPA) said 24 had died with swine flu and three with another strain of the virus since October.
Fatalities include nine children and 18 adults. Almost half of those who have died were in an "at risk" group eligible for vaccination although it remains unclear if any were pregnant.
Just one of the 22 people who died, and whose vaccination status was known, had received the most up-to-date flu vaccine.
Cases of flu and other infections including colds, bronchitis and pneumonia have dramatically increased in recent weeks although doctors say levels are normal for the time of year.
Rates of flu are highest in school children. Evidence suggests patients with asthma or obesity are suffering more serious complications if they develop flu.
Deaths from all causes are now above upper limits of expected levels for December, probably due to the cold weather and higher levels of viral infections.
Officials from the HPA said vaccination levels against flu remained low.
Some 43 per cent of at-risk groups under the age of 65 have had the jab, compared with 68.5 per cent of over-65s.
New figures are today expected to show a rise in the numbers of critically-ill patients suffering with flu being treated in intensive care units.
Nineteen patients are receiving specialist intensive care treatment, known as extra corporeal membrane oxygenation.
The treatment for the most severe cases of flu uses an artificial lung to oxygenate the blood outside the body.
Prof John Watson, head of respiratory diseases at the HPA, said: "The level of flu activity we are currently seeing is at levels often seen during the winter flu seasons, but due to the fact that H1N1 (swine flu) is one of the predominant strains circulating at the moment, we are seeing more severe illness in people under the age of 65 than we would normally expect.
"Flu can be an extremely serious illness for people in at-risk groups, including pregnant women, the elderly and those with other underlying conditions such as heart problems, diabetes, lung, liver or renal diseases and those who have weakened immune systems.
"Flu vaccination offers the best protection from seasonal flu and we continue to urge those in risk groups, including pregnant women at any stage of their pregnancy and healthcare workers, to get vaccinated as soon as possible. The vaccine is safe and effective.
"While it is impossible to predict with any certainty the extent to which flu will affect the community each year, recent research conducted by the HPA has suggested that a very substantial wave of activity associated with the pandemic strain is not likely.
"Nevertheless, activity with H1N1 this winter was expected, particularly in younger age groups, and this, combined with influenza B activity and other winter respiratory viruses has caused a high level of illness at the moment."
Prof Dame Sally Davies, interim chief medical officer for England, said rates of flu were within the expected range for the time of year.
But she said the difference was that swine flu affected younger people.
"They are young, some are pregnant, and it is not only people in at-risk groups," she added.
Health Secretary Andrew Lansley said: "Thanks to robust planning, the NHS is responding well to winter pressures.
"We will continue to monitor the situation carefully and respond as necessary."