Government plans for a new central purchasing system for the seasonal flu vaccine have been strongly criticised by GPs and pharmacists.

Currently, GPs order vaccines for seasonal flu directly from manufacturers or their suppliers, and are paid for providing the service through their contract. But under the proposed central system, the Department of Health would hold a contract with manufacturers and order vaccine based on data on requirements supplied by GPs, who would then place orders for vaccine with the Department.

Ministers say the proposed changes would reduce the burden on GPs and save the NHS up to an estimated £40 million a year. However, GP leaders have told a Department consultation that the moves could actually cut vaccination levels by removing the incentives provided by the "on-cost" profits on vaccine purchasing, which the Department calculates at around £20 million, or £555 per practice.

"The proposed changes reduce incentives for GP practices. This may be followed by a reduction in the uptake and rate of flu vaccination," warns the Royal College of General Practitioners (RCGP), in its response to the consultation. "High immunisation rates rely on the enthusiasm of the team, and removing incentives could have negative effects on this," it adds.

The British Medical Association (BMA)'s response notes that, given that there was no uplift to GPs' net pay in 2011/12, it is "extremely concerned about yet another potential loss of GPs' income streams" and that it fails to see how central procurement would increase immunisation rates.

One reason for the low levels of uptake last winter was the lack of a national advertising campaign, and this needs to be urgently addressed before the next flu season, says the BMA.

The Dispensing Doctors Association (DDA) also points to the positive effect that on-cost has on vaccination rates. "The fact that wasted flu vaccine is currently a direct, immediate and easily-quantifiable cost to a practice is a very strong lever to ensure all eligible patient groups are reached. That level will be absent in the proposed system and is likely to lead to reduced uptake," said DDA chief executive Dr David Baker.

The DDA's proposal is for a hybrid procurement system, under which GPs would source vaccines as they do now, but with the additional back-up of reserve supplies held centrally by Primary Care Trusts (PCTs) and a facility for practices to share vaccine supplies without falling foul of wholesaling regulations.

Pharmacy groups also say they "remain unconvinced" that central procurement is the answer to low uptake amongst target groups. In a joint response to the consultation, the Pharmaceutical Services Negotiating Committee (PSNC), Pharmacy Voice and the Royal Pharmaceutical Society (RPS) call instead for a focus on improving access by widening the network of providers, especially community pharmacies, which they say has been shown to have the effect of increasing uptake.

"Furthermore, central procurement has the potential to disrupt the supply of vaccine for private immunisations, which would get in the way of an increasingly popular route of access for people wishing to take responsibility for maintaining good health over the winter period," said Rob Darracott, chief executive of Pharmacy Voice.

"Clinical professionals should be able to access stock at all times, and be able to provide flu vaccinations at the most convenient locations for patients to maximise uptake," he added.

Barbara Parsons, head of pharmacy practice at the PSNC, warned that the benefits of pharmacies providing flu vaccinations - as demonstrated in the 2010/11 winter season - would be lost if they were unable to readily obtain vaccine supplies.

"Pharmacies have a proven track record of efficient medicines procurement, and we believe that it is better to draw on this expertise rather than attempt to develop alternative and potentially more costly centralised distribution models," she said.