Dendrogram of the 5´ end of open reading frame 2 of noroviruses, including the Shaibah strain. Scale at the top shows percent relatedness between different strains. GenBank strains are Alphatron/1998/NL (AF195847), Seacroft/1990/UK (AJ277620), Hillingdon/1994/UK (AJ277607), Melksham/1995/UK (X81879), Mexico/1989/MX (U22498), Hawaii/1972/US (U07611), Idaho Falls/378/1996/US (AY054299), Virginia207/1997/US (AY038599), Amsterdam/1998/NL (AF195848), Leeds/1990/UK (AJ277608), Grimsby/1995/UK (AJ004864), Lordsdale/1995/UK (X86557), Desert Shield/1990/SA (U04468), Winchester/1995/UK (AJ277609), Chiba407/1987/JP (AB022679), Musgrove/1989/UK (AJ277614), Sindlesham/1995/UK (AJ277615), Norwalk/1969/US (M87661), and Southampton/1991/UK (L07418). The sequence of the Shaibah/2003/IQ strain can be obtained from the Enteric Virus Unit, Virus Reference Department, Centre for Infections, Health Protection Agency (christopher.gallimore@hpa.org.uk).