Changing patterns of rotavirus strains circulating in Ireland: re-emergence of G2P[4] and identification of novel genotypes in Ireland.

Worldwide, Group A Rotavirus (RVA) is recognized as the most common aetiological agent of acute diarrheal disease in children. One hundred and ninety seven positive faecal samples were obtained from patients between 2006 and 2008. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to amplify the VP7 and VP4 gene segments of these samples, and G and P typing was carried out subsequently. The most common strain type was G1P[8], and the emergent global G9-type was identified in both years. RVA strain type G2P[4], previously reported in Ireland in 1999, was also detected. Genotypes G2 and G3 in combination with P[4] were detected in 2006-2007 only. There was also an emergence of strain types including G3P[4], G9P[4], G2P[4 + 8] and G2G4P[8] in this study. Molecular analysis of the VP7 genes revealed G1 strains circulating within lineage Ic as previously reported in Ireland. In addition, new sublineage within lineage I of G1 strains was also identified. Analysis of G4 strain NRVL-Hum-49 revealed similarity with other human G4 viruses in lineage Ib. G9 strain NRVL-Hum-74 clustered with a unique G9 strain, CIT-254, in lineage IIIc. This data supports the observations made that the profile of RVA strains in Ireland appears to be dynamic. This study demonstrates that the circulation of human rotavirus is changing continuously in Ireland, and continued surveillance of the circulating strains is needed to detect the appearance of new strains, or new variants which may lead to vaccine breakthrough.

Detection and characterisation of bovine rotavirus in Ireland from 2006-2008.

BACKGROUND: Worldwide, Group A bovine rotavirus (RVA boRV) is one of the main causes of neonatal calf diarrhoea. Currently, limited epidemiological and sequence data exists on the RVA disease in bovines in Southern Ireland only. The aim of the study was to generate epidemiological and sequence data of RVA boRV distributed over a wide geographical area in Ireland. FINDINGS: 272 stool samples were obtained from symptomatic calves and analysed to identify the prevalent G and P genotypes. Viral type combinations including G6P[5], G6P[11] and G10P[11] genotype were the most frequently identified. The G6P[5] combination was predominant throughtout the study, accounting for 70% (n = 191). Sequence analysis of the VP7 gene revealed that Irish G6 strains fell within Lineage IV, similiar to previous reports in Ireland. CONCLUSION: The detection of unusual G and P combinations may have an impact on rotavirus control programmes and current vaccines may need to incorporate new strains, as the current vaccine available may not offer protection against all of these circulating types.

Complete genomic sequence analyses of the first group A giraffe rotavirus reveals close evolutionary relationship with rotaviruses infecting other members of the Artiodactyla.

Group A Rotaviruses (RVA) have been established as significant contributory agents of acute gastroenteritis in young children and many animal species. In 2008, we described the first RVA strain detected in a giraffe calf (RVA/Giraffe-wt/IRL/GirRV/2008/G10P[11]), presenting with acute diarrhoea. Molecular characterisation of the VP7 and VP4 genes revealed the bovine-like genotypes G10 and P[11], respectively. To further investigate the origin of this giraffe RVA strain, the 9 remaining gene segments were sequenced and analysed, revealing the following genotype constellation: G10-P[11]-I2-R2-C2-M2-A3-N2-T6-E2-H3. This genotype constellation is very similar to RVA strains isolated from cattle or other members of the artiodactyls. Phylogenetic analyses confirmed the close relationship between GirRV and RVA strains with a bovine-like genotype constellation detected from several host species, including humans. These results suggest that RVA strain GirRV was the result of an interspecies transmission from a bovine host to the giraffe calf. However, we cannot rule out completely that this bovine-like RVA genotype constellation may be enzootic in giraffes. Future RVA surveillance in giraffes may answer this intriguing question.

Molecular characterisation of a bovine-like rotavirus detected from a giraffe.

BACKGROUND: Rotavirus (RV), is a member of the Reoviridae family and an important etiological agent of acute viral gastroenteritis in the young. Rotaviruses have a wide host range infecting a broad range of animal species, however little is known about rotavirus infection in exotic animals. In this paper we report the first characterisation of a RV strain from a giraffe calf. RESULTS: This report describes the identification and detailed molecular characterisation of a rotavirus strain detected from a 14-day-old Giraffe (Giraffa camelopardalis), presenting with acute diarrhea. The RV strain detected from the giraffe was characterized molecularly as G10P[11]. Detailed sequence analysis of VP4 and VP7 revealed significant identity at the amino acid sequence level to Bovine RV (BoRV). CONCLUSION: This study demonstrates the need for continuous surveillance of RV strains in various animal populations, which will facilitate the identification of rotavirus hosts not previously reported. Furthermore, extending typical epidemiology studies to a broader host range will contribute to the timely identification of new emerging strain types.