UK researchers found that vaccinating children aged five to 16 could prevent more deaths each winter than giving the jab to at-risk groups alone.
The findings, published in PLOS Medicine, support the DH's plan to roll out vaccination to all children aged two to 17 years over the coming years.
A team from the London School of Hygiene & Tropical Medicine and colleagues combined figures on GP consultations for flu-like illness with information on how viruses spread in the community and data on levels of immunity.
They calculated that 0.39 infections had been prevented and 1.74 lives had been saved for every 1,000 doses over the past 14 years.
But their predictions found that expanding the programme to five to 16-year-olds could prevent 0.7 infections and save 1.95 lives per 1,000 doses.
Authors said: 'The most efficient way of reducing overall influenza-attributable morbidity and mortality appears to be to target the key spreaders - children. Even with modest coverage, substantial further reductions in morbidity and mortality could be achieved.'
The NHS began routinely vaccinating two and three-year-olds in September as part of a new childhood flu vaccination programme.