Predominance of G9P[4] Rotavirus from Children with Acute Gastroenteritis in Northwestern Mexico.

In Mexico, group A rotavirus (RVA) infections remain the most common cause of severe dehydrating diarrhea in children. This study was conducted to examine the circulating RVA strains in the northwest region of Mexico. RVA strains collected from stool samples of children were genotyped, and their partial sequences were analyzed. RT-PCR of the VP4 and VP7 genes showed the partial G9P[4] genotype in all the samples. Sequencing and phylogenetic analysis of the partial VP7 gene amplicons of 10 strains showed that they clustered in the RVA G9 lineage III, and 7 of them showed 100% identity with the reference strain LB1562, which was collected in the USA 2 years earlier. The amino acid sequences of the VP7 and VP4 antigenic regions were highly conserved between the analyzed RVA strains. Active surveillance is important for monitoring the emergence of RVA strains and their impact on cases of gastroenteritis.