National case-control study of Salmonella Enteritidis Phage Type 14b infection in England and Wales implicates eggs used in the catering trade O'Brien, S and Gillespie, I A and Charlett, A and Adak, G K and Threlfall, E J and Ward, L, Weekly releases (1997–2007), 8, 2388 (2004), https://doi.org/10.2807/esw.08.08.02388-en