One baby has died and six others were in an isolation ward tonight after a bug hit a hospital's neo-natal unit.

The baby, who was born prematurely at Birmingham's Heartlands Hospital almost two weeks ago, was one of two to become infected with Serratia bacteria.

Staff at the Bordesley Green hospital are hopeful the second baby infected with the bug will go home "in the next few weeks", a spokeswoman said today.

Five other babies, who tested positive for Serratia on their skin, are in a six-cot isolation unit as a "precaution" the spokeswoman added.

Hospital director Lisa Dunn said: "Two extremely pre-term babies were infected with the bacteria: very sadly one baby died. The second baby is doing very well and should be going home in a few weeks' time.

"Serratia is an organism which has appeared in neonatal units across the NHS from time to time.

"It can be controlled by putting in place special arrangements to prevent spread of infection.

"Serratia was discovered on some babies on our unit recently and such measures were immediately implemented and remain in place.

"This has included closing our intensive care room to new admissions.

"These measures have been very successful in preventing the bacteria spreading and the intensive care facility is expected to reopen to new admissions this week.

"Meanwhile many other babies have been safely cared for in separate rooms on the unit without any of them being affected by the bacteria."

Serratia, which causes infections in the blood and respiratory tracts, can prove deadly if it attacks under-developed lungs.

A hospital spokeswoman said the five babies who tested positive for the bacteria on their skin were not "infected" because the bug had not entered their bodies.

The identity of the baby who died, and the precise dates of its birth and death, cannot be revealed for patient confidentiality reasons.

A hospital spokeswoman said the cause of death recorded on the death certificate was natural causes.