NHS workers' fears about the private finance initiative are boosting recruitment to trade union Unison.

National officer Stephen Weeks said: 'We have had a number of reports that it does revive interest in the union.' He said the gains were 'more a consolidation' than a 'dramatic' rise, but cited as examples Dudley Group of Hospitals branch - where 600 ancillary workers took strike action in a protracted dispute against transferring to a private company in a PFI deal - and Stoke Mandeville, one of the sites where negotiations are under way on a pilot PFI scheme to keep staff in the NHS.

Dudley Group of Hospitals joint branch secretary Angela Thompson said: 'In the lead-up to the dispute we gained a lot of members, and all the way through the strike we gained membership.'

Mr Weeks added: 'Where PFIs have gone ahead, there are places where there has been significant recruitment among new staff. At Norfolk and Norwich, the branch is very focused on getting a unified workforce.'

Norfolk regional officer for health Brian Lynch said: 'Our membership is in the high 80s as a percentage of the contracted-out staff, and you would [usually] be lucky to have 30 per cent.'

Discontent among NHS members of the MSF union, set to merge with the engineers' AEEU, is also adding to Unison's ranks.

HSJ understands that a group of staff at Leeds Teaching Hospitals trust - with their union representative - have left MSF to join Unison.

And former MSF official Gerry Looker, who was deputy to the union's high-profile former head of health Roger Kline, has also reappeared in Unison colours as a regional officer in the Nottingham office.