An NHS trust has admitted that a highly vulnerable baby died because of contaminated feed that it gave her, after denying that for more than a decade.

At an inquest on Tuesday, Guy’s and St Thomas’ trust said it had given Aviva Otte a nutritional product containing deadly bacteria in January 2014. It had previously insisted to her mother, a coroner and the Guardian on multiple occasions that she had died of natural causes.

The change in GSTT’s explanation of Aviva’s death came during the second day of an inquest into her death and the deaths of two other babies in a separate outbreak of Bacillus cereus five months later.

Giving evidence at Southwark coroner’s court in London, Dr Grenville Fox – a senior consultant neonatologist who worked in the neonatal unit where Aviva was treated – said that it was now his opinion that the parenteral nutrition she received was the main cause of her death.