The Government is injecting millions into the flu vaccination programme on the condition NHS trusts prove at least 75% of their staff have been immunised against the disease.
Two pots of £250 million have been set aside to fund the programme this year and in 2014.
However, health secretary Jeremy Hunt said NHS trusts would only have access to the funds when they could prove 75% of their workforce had already been immunised against the flu.
Scientists have found a "blueprint" for a universal flu vaccine, according to the leader of a research project into influenza, said Professor Lalvan:
Our findings suggest that by making the body produce more of this specific type of CD8 T cell, you can protect people against symptomatic illness. This provides the blueprint for developing a universal flu vaccine.
We already know how to stimulate the immune system to make CD8 T cells by vaccination.
Now that we know these T cells may protect, we can design a vaccine to prevent people getting symptoms and transmitting infection to others.
This could curb seasonal flu annually and protect people against future pandemics.
British scientists are one step closer to developing a "holy grail" universal flu vaccine that would tackle all strains of the illness.
A successful jab would stimulate the body to create more immune cells capable of attacking the virus and could be effective at preventing new strains that cross into humans from birds and pigs, according to scientists.
Results from the 2009 swine flu pandemic showed patients with more virus-killing immune cells in their blood at the start of the illness, would avoid sever illness, researchers at Imperial College London (ICL) found.
Professor Ajit Lalvani from the National Heart and Lung Institute at ICL, who led the study, said: "New strains of flu are continuously emerging, some of which are deadly, and so the holy grail is to create a universal vaccine that would be effective against all strains of flu."
Influenza kills between 250,000 and 500,000 globally per year, according to the World Health Organisation.
Children aged two and three will be vaccinated against flu for the first time in a raft of new Government measures to prevent a winter health crisis.
Health Secretary Jeremy Hunt presented the step as part of his strategy to help the most vulnerable during the winter months after announcing an ambitious plan to overhaul the way A&E departments cope with increased pressure.
He told reporters that NHS trusts will have to ensure that 75% of all their staff have been vaccinated against flu to gain access to a new £500 million A&E fund next year.
This winter 53 of the most "at risk" A&E departments across the country will have access to the fund to help them provide extra consultant care, improve care for those with long-term conditions and integrate better with social care teams.
All children aged two to 17 are to be given the flu vaccination through a nasal spray, the Health Department announced today.
The programme was supposed to be rolled out throughout 2014 but experts today said that two-year-olds will be offered the spray from September this year.
The UK will become the first country to offer the flu vaccine to healthy children free of charge.
Healthy children are among those who are least likely to develop complications from being infected by flu, but their close contact with each other means they are more likely to transmit the virus to one another and other vulnerable people.
As many as 375,000 workers are expected to take the day off work today, with half of the country's bosses admitting they do not always believe those who phone in sick.
The post-Christmas blues, poor weather and a long wait for the summer holiday season are just a few of the factors involved as Brits stay at home.
Latest figures from the Health Protection Agency inidcate that the number of flu cases is continuing to increase.
Several indicators include GP consultation rates, the proportion of calls to NHS Direct and new admissions to intensive care of high dependency units.
Children aged five to 14 in particular have been the group most affected by flu so far this season.
Dr Richard Pebody, head of seasonal flu surveillance at the HPA said: “Vaccination against flu is still the most effective way of preventing the virus in people who are in an ‘at risk’ group, as they are more vulnerable to developing complications from flu.
"This includes people with underlying conditions such as heart problems, diabetes, lung, liver or renal diseases and those with weakened immune systems, as well as older people and pregnant women."
Researchers say flu levels are still very low but overall the results suggest that the English region most affected by the virus is the North East with 19,200 per 100,000.
Dr Alma Adler, Research Fellow at the London School of Hygiene & Tropical Medicine said: "We now need more people to sign up and let us know how they are feeling so we can study these figures in greater depth and increase our understanding of seasonal flu."
We are seeing an increase in flu activity mainly among school children indicating the start of this year's flu season.
Flu vaccination is still the most effective way of preventing flu and it is not too late to get it so we would encourage all those who are in 'at risk' groups to get vaccinated as they are more vulnerable to developing complications from flu.
These include people with underlying conditions such as heart problems, diabetes, lung, liver or renal diseases and those with weakened immune systems, as well as older people and pregnant women.
An increase in the number of children aged five to 14 falling ill means the flu season has officially begun. Doctors say anti-viral drugs should be given to people at risk of developing complications from flu - and it's not too late to have a vaccination