Salmonella Typhimurium DT8 causes a similar illness to other forms of Salmonella infection, so symptoms can include diarrhoea, vomiting, abdominal pain and fever, reports HPA.

So far this year, the HPA has confirmed 66 reports of human infection in England and Northern Ireland. Figures for previous years were 34 in 2008 and 47 in 2009.

Of the reported cases, two are known to have been hospitalised, one of whom has died. Cases are mainly adults with an average age of 46 years, and most are men (61 per cent). Cases have been referred from Northern Ireland and most regions in England, with predominance in the South-East and North-West.

Dr Dilys Morgan, who is leading the investigation for the HPA, said: "As soon as the Agency first noticed an increase in cases we started detailed investigations using food questionnaires and interviewing cases to find the common cause of illness in these people and to identify the source of the outbreak.

"It became clear from our investigations that the increase was related to the consumption of duck products, mainly eggs. It is important that consumers and caterers are aware that all eggs, including duck eggs, may occasionally be contaminated with Salmonella and follow advice provided by the Food Standards Agency in order to reduce the risk of infection. Eggs should be cooked thoroughly and good hygiene practices, such as washing hands, utensils and kitchen surfaces should be followed after handling or using duck eggs."

In a related move, the Food Standards Agency (FSA) has reminded consumers and caterers of the importance of good hygiene practice when cooking with and consuming duck eggs.

The FSA's advice on good hygiene practices with eggs can be found by clicking here.