Maribel Matula Espada and her husband Wen were overjoyed when they discovered they were about to have their first child.

Despite a difficult labour followed by an emergency Caesarean, Mrs Espada, a nurse in Stoke-on-Trent, gave birth to a healthy baby boy at the University Hospital of North Staffordshire, the hospital in which she had worked for four years.

But six days after "the most exciting day of her life", the nurse whose teenage ambition had been to care for others, was dead.

Mrs Espada, 33, died on 26 September after contracting the deadly PVL strain of the MRSA virus. She had been working as a D-grade staff nurse on the hospital's diabetic ward.

Speaking to The Independent yesterday, Mr Espada, 30, a warehouse worker who had met his wife in the Philippines, described the sudden deterioration in his wife's health after giving birth to their son, Arwen.

"She held our baby and she was so happy. She asked me if I was excited too. I am absolutely heartbroken. It was the worst and best time of my life. It was all very sudden. We had only just moved into our new house and were looking forward to our new life with our son. She got ill a few days later. I was helpless and I could see she was dying.

"When the doctors told me she had died I was numb. I had no idea why she had died. They never mentioned MRSA and they had not mentioned to my wife that there had been an outbreak of MRSA even though she worked at the hospital.

"I think it is terrible what has happened and if the hospital has tried to cover this up they should be made to pay for it," he added.

He went to the Philippines to bury his wife and returned to his job this month. Their son is still being cared for in the Philippines by members of Mr Espada's extended family.

He said that his wife had a passion for nursing and had worked in Singapore after training in the Philippines as a teenager. "I met my wife because I was friends with her brother. She was a strong, healthy woman who was hard working and highly-motivated. She was 17 when she decided she would do nursing and she loved being a nurse," he said.

Mr Espada has now instructed a solicitor to help determine when and where she picked up the infection.

Stephen Maguire, from Donns LLP Solicitors, said he would investigate the hospital's internal procedures. "She went into hospital for a routine delivery of a child, which led to an emergency Caesarean. It is one of the most tragic cases of MRSA that I have come across.

"At this stage, our primary concern is to investigate what, if anything, went wrong with the hospital's internal procedures and why Mrs Espada was exposed to such a virus.

"We will examine whether the hospital followed the national and internal protocols for minimising risk of cross infection. Once we have concluded our inquiries we will be in a better position to determine whether the situation was avoidable," he said.

Another patient died at the hospital after receiving care in March. The hospital has confirmed that 11 people, including the two who died, became infected with the PVL-producing strain of MRSA, which had been seen in the UK before, but usually in the community rather than a hospital setting, according to the Health Protection Agency.

The commonly known "hospital-associated MRSA" strains are usually associated with elderly hospital patients, but PVL attacks white blood cells, leaving the victim unable to fight infection, irrespective of age or fitness.