Public Health England (PHE) is finalising pilots to test the level of workload and vaccine uptake that could be expected from the upcoming mass roll-out of vaccination to all primary school children, planned for 2014.
It comes as the DH's Joint Committee on Vaccination and Immunisation (JCVI) advised that most children should receive only one dose of the Fluenz vaccine this winter, instead of two as advised by the manufacturer.
One million children aged two and three years will be offered flu vaccination this winter as the first step towards extending the programme to all children aged two to 17 years.
Officials had originally intended to offer the vaccine to all two-year-olds from September 2014, after warnings there would not be enough vaccine available until then.
The pilots, revealed in a joint DH and PHE letter, will 'assess issues such as workload, uptake and logistics of delivery in a variety of settings that will reflect full-scale roll-out as closely as possible'.
These will take place mainly in primary schools. Children aged two and three years in these areas will be vaccinated via the GP contract as usual. Pilots will also take place in Wales, Scotland and Northern Ireland.
The JCVI recommended that healthy children should receive only one dose of the Fluenz vaccine this winter.
Although current DH guidance and the manufacturer advise two doses of Fluenz, the JCVI said a second dose provides only 'modest' extra protection.
The committee's experts said vaccinating many children with one dose would provide a greater benefit to public health than vaccinating fewer children with two doses.
However, children in at-risk groups should receive two doses, they said.