A mother who lost her five-year-old son to E.coli has said she wants answers about his death from a public inquiry into the fatal outbreak of the bug.

Mason Jones, a pupil at Deri Primary School near Bargoed, South Wales, died in 2005 after contracting the 0157 strain of the bug in what is believed to have been the UK's second largest E.coli outbreak.

More than 150 other people, many of them children, were affected as it spread through 44 schools. A total of 31 were admitted to hospital that autumn.

The six-week public inquiry began with a moment's silence for Mason. Microbiologist Professor Hugh Pennington, who is chairing the inquiry, said the little boy was "very much in my mind".

It was confirmed that butcher William John Tudor who supplied schools with contaminated meat will not give evidence to the inquiry. He was jailed for 12 months in September after admitting placing unsafe food on the market.

Opening the hearing in Cardiff, senior counsel to the inquiry James Eadie QC said Tudor had declined repeated invitations to provide a statement. "That is his choice," Mr Eadie said.

He said the inquiry had decided not to use its power to call him to give evidence.

"There is evidence from experts, evidence from employees and others gathered at the time by the police," he said.

"Moreover, by his guilty plea, he has accepted at least the central thrust of the case the local authorities made against him."

Mr Eadie said the only thing connecting all the schools involved in what was the UK's second biggest E.coli outbreak was meat from Tudor's Bridgend-based company, John Tudor & Son.

There were 157 probable cases of the 0157 strain and 118 confirmed cases during the outbreak. It was not declared over until December 20, 2005.

Before the hearing, Mason's mother Sharon said: "At the moment what is going through my mind is that we are going to get answers to something we have waited for for two-and-a-half years. It has been a long wait for us.

"We need to get justice for Mason and the other children who were affected."

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