The government will today announce that the national flu vaccination programme will be extended to all children in the UK.

Once the programme is up and running the vaccine will be offered to all children aged from two to around 17 years on the NHS. The government said it was yet to be decided how the vaccine would be delivered, for example by school nurses or in primary care.

The move follows recommendations from the Joint Committee on Vaccination and Immunisation, which advises the Department of Health.

The programme currently covers children in “at risk” categories, for example with long-term conditions such as asthma, but a debate has been running for a number of years on whether it would be cost-effective to extend the programme to all children.

The joint committee recently concluded that while there were significant challenges involved in extending the programme, evidence suggested these were outweighed by the benefits that a comprehensive immunisation programme could bring.

Children’s close contact with each other means they are more likely to transmit the virus to other more vulnerable groups – including infants and the elderly.

The committee believes even with moderate vaccination uptake among children of around 30%, the increase in “herd immunity” could see a drop of around 40% in the number of people of all ages affected by flu each year.

The DH said the impact of this would mean at least 11,000 fewer hospitalisations as a result of flu and around 2,000 fewer deaths a year.

But the department added that “a number of key aspects now need to be looked at”, including who will deliver the vaccine and how to source enough of it.

The programme will use a nasal spray vaccine, which has been available for around a decade in the US. However, there will not be sufficient capacity to deliver enough vaccine for the expanded programme until 2014 at the very earliest, the DH said.

The vaccine will need to be given to the children during a six to eight week period prior to the flu season.

Chief medical officer for England Dame Sally Davies said: “There are significant challenges to delivering a programme that requires up to nine million children to be vaccinated during a six week period and we will look at the recommendations in detail to decide how best to develop and deliver the programme.”

Unite professional officer Dave Munday said the union welcomed the decision to expand the programme but highlighted that there would need to be a “dramatic increase” in the number of school nurses if the vaccination was to be delivered by this group of health professionals.

“It is important to remember that the school nursing service remains under the cosh of increased work loads without the same increase in the number of staff, without any increase in responsibility regarding new immunisations to the schedule,” Mr Munday said.