Abstract:
Norovirus (NoV) is the second most important cause of viral diarrheal disease in children
worldwide after rotavirus and is estimated to be responsible for 17% of acute diarrhea in low-income
countries. This study aimed to identify and report NoV genotypes in Mozambican children under
the age of five years with acute diarrhea. Between May 2014 and December 2015, stool specimens
were collected within the Mozambique Diarrhea National Surveillance (ViNaDia) and tested for NoV
genogroups I (GI) and II (GII) using conventional reverse transcriptase-polymerase chain reaction
(RT-PCR). Partial capsid and RNA-dependent RNA polymerase (RdRp) nucleotide sequences were
aligned using the Muscle tool, and phylogenetic analyses were performed using MEGA X. A total of
204 stool specimens were tested for NoV. The detection rate of NoV was 14.2% (29/204). The presence
of NoV was confirmed, by real-time RT-PCR (RT-qPCR), in 24/29 (82.8%) specimens, and NoV GII
predominated (70.8%; 17/24). NoV GII.4 Sydney 2012[P31] was the predominant genotype/P-type
combination detected (30.4%; 7/23). This is the first study which highlights the high genetic diversity
of NoV in Mozambican children and the need to establish a continuous NoV surveillance system.
