Norovirus infection in children with acute gastroenteritis, Madagascar, 2004-2005

Of 237 children with acute gastroenteritis in Antananarivo, Madagascar, during May 2004-May 2005, 14 (≈6%) were infected with norovirus. Seasonality (November-December peak) was detected. Reverse transcription-PCR identified GII as the most common genogroup. GIs belonged to GI.1, GI.3, and GI.4. Noroviruses in Madagascar show extensive genetic diversity.