The parents of 63 babies born at the Norfolk and Norwich University Hospital neo-natal unit are being contacted to help identify the source of a bacteria.

Seven babies have so far been infected by an outbreak of PVL which attacks white blood cells leaving the sufferer unable to fight infection.

One baby - a boy born prematurely to a couple from Dereham - died after contracting the PVL infection.

Seven sets of parents have still to be contacted.