THE trial of Lucy Letby has heard the Countess of Chester Hospital neonatal unit nurse tried to poison a new-born twin with insulin.

Letby 32, of Arran Avenue, Hereford, denies seven counts of murder and 15 counts of attempted murder, in relation to the deaths of seven babies at the Countess of Chester Hospital and the attempted murder of 10 more.

Prosecuting at Manchester Crown Court on Tuesday, October 11, Nicholas Johnson KC had said Child F was the twin brother of Child E, who he had previously said was murdered by Letby, with the babies' mum seeing Letby "trying to attack" the new-born boy.

The day after allegedly murdering child E in August 2015, Lucy Letby allegedly used insulin for the first time to poison a baby, the court heard, in trying to murder child F.

Child F was prescribed a TPN (total parenteral nutrition) bag of fluids and later suffered an unexpected drop in his blood sugar levels and surge in heart rate. Checks on his insulin levels were carried out which showed, “conclusive evidence” someone had given child F insulin to poison him.

Mr Johnson said no other baby on the neo-natal unit was prescribed insulin so child F could not have received the drug intended for some other child by negligence.

Mr Johnson said the prosecution allege Letby had injected insulin into the TPN bag before it was hung up to give to the child.

He added: “You know who was in the room and you know from the records, who hung the bag.

“It can’t have been an accident.”

He told the jury there was only one, “credible candidate” for the poisoner.

“The same person,” he said, “Who was present at all the unexplained collapses and deaths at the Countess of Chester Hospital on the neo-natal unit.”

Mr Johnson later gave the prosecution's version of events which led to the alleged, and repeated, attempted murder of Child G, a very premature baby girl born at Arrowe Park Hospital in May 2015, weighing just 1lb 2oz.

He alleged Letby made three attempts to murder Child G - once on the night of September 7, and twice during the day of September 21.

On the first two occasions, the prosecution said Child G was overfed and vomited violently as a result.

Mr Johnson told the court: "The practice of the nurses on the neonatal unit was to use the nasogastral tube to check whether an infant had an empty stomach before feeding. That was done in Child G’s case – nothing came up which means there was nothing in her stomach.

"She was then fed and her designated nurse went on a break. 15 minutes later Child G produced projectile vomits of such force that they left the cot and landed on the floor and nearby chair.

"Child G collapsed and stopped breathing. An amount of feed was aspirated from her NGT equal to what she had been given about 15 minutes earlier together with lots of air.

"There was a similar episode a few weeks later.

"These were not naturally occurring, or random events; they were deliberate attempts to kill using a slightly different method by whilst Lucy Letby sought to give the appearance of chance events in the neonatal unit at the Countess of Chester Hospital."

In what the prosecution called the third attempt, Child G's monitoring equipment had been switched off and medical staff responded to Letby's cry for help. Child G was struggling to breathe and Letby was giving her ventilation breaths. 

An MRI scan a year later showed Child G had suffered irreversible brain damage.

In police interview, Letby accepted that the clear inference to be drawn from the events was that Child G had been given excess milk and air via the NGT.

She denied responsibility for either of those eventualities. She also denied switching off the monitoring equipment.

The prosecution will continue its opening of the case on Wednesday.