A freak nationwide outbreak of salmonella in bean sprouts is being investigated as the possible cause of the death of an 82-year-old Jewish woman who died after a wedding in Manchester.

Rene Kwartz, from Crumpsall, was one of 10 guests at the wedding, held in Prestwich in August, who contracted a rare form of salmonella called S Bareilly. She was the bride's great-aunt and, according to the coroner, died from pneumonia, contributed to by salmonella enteritis.

The Health Protection Agency (HPA) has now identified 140 S Bareilly cases across the UK since the beginning of August - ten times the number in a typical month.

New biological evidence due to be released yesterday suggests that the source of the national outbreak is bean sprouts after salmonella was found at a UK supplier of the vegetable.

Guests at the wedding were served salmon with noodles and bean sprouts. All 10 guests who fell sick have been confirmed as infected with S Bareilly - but health officials stressed that no conclusion about the source of infection has been reached.

There have been 140 case of the infection across UK

A spokesman for the HPA said: "The 82-year-old woman who sadly died had been suffering from Salmonella Bareilly infection. This is the only death that I'm aware of. The wedding-associated outbreak is part of the national investigation into an increase in S Bareilly cases in England and Scotland."

The HPA said that 100 questionnaires have been received from wedding guests to help identify a common source of the infection.

But health officials confirmed that no trace of infection has been found at the premises of the wedding's Manchester kosher caterer, Shefa Mehadrin, following rigorous hygiene testing.

Law firm Pannone, which is suing Shefa Mehadrin on behalf of 20 wedding guests, however, said that caterer may still be liable.

Pannone's Clare Campbell said: "News from the Food Standards Agency saying that there are possible links between a series of nationwide incidents of a rare form of salmonella and raw bean sprouts does not alter the fact that the caterer is liable under law - even if the caterer was not aware of the problem with the bean sprouts they used."

A spokesperson for Manchester-based Shefa Mehadrin said: "We are unable to make any further comment until the findings of the HPA's investigation are known."

The Food Standards Agency has said bean sprouts are safe to eat but advised fully cooking the vegetable before serving, especially to people with weakened immune systems and the elderly.