Molecular characterization of a novel recombinant strain of human astrovirus associated with gastroenteritis in children

• Published in: Archives of virology Vol. 146; no. 12; pp. 2357 - 2367
• Main Authors: WALTER, J. E, BRIGGS, J, GUERRERO, M. L, MATSON, D. O, PICKERING, L. K, RUIZ-PALACIOS, G, BERKE, T, MITCHELL, D. K
• Format: Journal Article
• Language: English
• Published: Wien Springer 01.12.2001; New York, NY Springer Nature B.V; Springer-Verlag
• Subjects: Animals; Astroviridae Infections - epidemiology; Astroviridae Infections - virology; Bacteriology; Biological and medical sciences; Child Day Care Centers; Child, Preschool; Disease Outbreaks; Epidemiology; Feces - virology; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gastroenteritis - epidemiology; Gastroenteritis - virology; Human astrovirus; Humans; Immunoenzyme Techniques; Mamastrovirus - classification; Mamastrovirus - genetics; Mamastrovirus - isolation & purification; Mexico - epidemiology; Microbiology; Molecular immunology; Molecular Sequence Data; Nucleic Acid Conformation; Phylogeny; Recombination, Genetic; Reverse Transcriptase Polymerase Chain Reaction; RNA, Viral - chemistry; RNA, Viral - genetics; Sequence Analysis, DNA; Serotyping; Techniques; Texas - epidemiology; Urban Population; Central America; Mexico; United States; North America; Texas; America; USA, Texas, Houston; Mexico, Mexico City; Human; Typing; Enzyme; Gastroenteritis; Diarrhea; Enzyme immunoassay; Virus; Characterization; Polymerase chain reaction; Astrovirus; Outbreak; Nucleotide; Digestive diseases; Intestinal disease; Isolate; Feces; Child; Gastric disease
• ISSN: 0304-8608; 1432-8798
• DOI: 10.1007/s007050170008

We report a naturally occurring human astrovirus (HAstV) strain detected in two different geographic locations. We identified two isolates of this strain in a diarrhea outbreak at a child care center in Houston, Texas; and two isolates in diarrhea stool samples from two children in Mexico City. All four isolates were detected in stool samples by enzyme immunoassay (EIA). One of the Mexican isolates was typed by EIA and all four isolates were HAstV-5 by typing RT-PCR. The four isolates were >97% nucleotide-identical in two different genomic regions: ORF1a (246 nt), and the 3' end of the genome (471 nt). One isolate from each geographic location was further sequenced in the transition region from ORF1b to ORF2 (1255 nt) and this region of the two isolates showed > or = 99% nt identity. Phylogenetic analyses of sequences of eight HAstV antigenic types and the novel strain in the transition region demonstrated the new strain being closely related to HAstV-3 in ORF1b, but closest to HAstV-5 in ORF2. These results and high sequence identity among all HAstV antigenic types in the transition region and RNA structural predictions supported a potential recombination site at the ORF1b/ORF2 junction. This is the first evidence that recombination occurs among human astroviruses.