The subtle symptoms of killer bacteria Listeria linked to NHS hospital deaths

Three people are dead and two are injured after eating chocolate mousse thought to be contaminated by listeria bacteria (Picture: PA/Getty)Listeria is believed to have left three people dead, putting the NHS on high alert, but its symptoms are not always obvious.The deaths, one of which has been confirmed, are thought to be linked to frozen chocolate mousse desserts supplied to the health service.While they are being recalled after an alert put out by the Food Standards Agency, it is still vita