Lucy Letby has suggested plumbing issues and “raw sewage” could have played a part in the deaths of the babies she is accused of murdering.

The nurse denies killing seven babies, as well as the attempted murder of 10 other infants, at Countess of Chester Hospital between 2015 and 2016.

The 33-year-old defendant was cross-examined about more of her alleged victims as she gave evidence again on Wednesday.

Letby trial latest – As it happened

Prosecutor Nick Johnson KC asked if Letby thought Child E’s death was the result of incompetence in the neonatal unit.

Letby said the infant could have been given a blood transfusion sooner, telling the trial “maybe that would have made a difference” and that staff were “collectively” responsible.

She told Manchester Crown Court that an “important factor to note, there were often plumbing issues within the unit”.

Asked what it had to do with the death of Child E, or any of the children, she said there was “raw sewage coming out of the sinks and running on to the floor in the intensive care unit”.

Letby said this could have had an effect – as well as staff being unable to properly wash their hands.

Child E died on 4 August 2015, allegedly murdered by an injection of air, after losing a quarter of his blood.

His twin (Child F) is said to have been attacked a day later via insulin poisoning, but survived.

The prosecution claims Letby didn’t escalate Child E’s bleeding until 10pm – an hour after they say it started, and that she falsified her notes.

The nurse denied the bleeding started before 10pm, despite his mother testifying she saw blood on his lip at 9pm.

“If I had seen blood at any point I would have escalated that to someone,” Letby told the court.

“My case is there was no blood prior to 10pm,” she added. “I don’t remember Child E’s mother coming down prior to that.”

Letby ‘looking for reaction from baby’s mum’

The accused also denied she was “obsessed” with the baby’s mother after she allegedly searched for her nine times on Facebook, including once on Christmas Day.

Mr Johnson said Letby was “looking for a reaction” from the woman to her son’s death.

But Letby replied she often thought of the family and believed she had a good relationship with their mother.

She was also questioned about Child G, a baby she’s accused of trying to murder by overfeeding her milk or injecting her with air.

The prosecution said the baby was attacked three times by Letby but recovered when she was moved to another hospital.

The prosecution told the court the girl was doing well and was due to go home when she collapsed for the first time.

Letby disputed this and said she still had “a number of ongoing issues”, adding there was “a possibility” her colleague could have “mis-measured” the milk and overfed the girl.

A photo of Child G’s cot from 6 September 2015 was shown to the jury, with a splatter of vomit pictured on the floor and on a nearby armchair.

After Letby admitted she hadn’t seen such projectile vomiting before, Mr Johnson asked why she hadn’t mentioned it to police as it would have “stuck in her mind”.

“I haven’t lied, it was in her cot, I just haven’t in that moment specified where else it went,” she told the court.

Mr Johnson said the alleged attack on the baby had “echoes” of the deaths of babies C and E.

“You inserted something into Child G’s airway, didn’t you?” he asked Letby.

“No”, she replied.

“You caused the bleeding, as you did with many of these children,” he added.

“No, that’s not true”, said Letby.

Letby also denied she was “looking for an opportunity to finish [Child G] off” when asked why she returned to the hospital on the day of the vomiting incident.

“I didn’t visit Child G, no. I went to do what I needed to do,” she told the court, adding that she was sorting out some documentation.

Letby, from Hereford, denies all the charges. The trial continues.