Rotavirus is the most common etiological cause of acute viral gastroenteritis in infants and young children worldwide, yet its role in the adult population is less well understood. We have recently identified rotavirus as the causative agent of severe diarrhea in adults, specifically in two gastroenteritis outbreaks in separate care for the elderly homes. Strain typing has shown the continued presence of P[8]G1, the emergence of P[8]G9, and the reemergence of P[8]G4. A total of 26 community cases and 6 outbreak cases of rotavirus infection, positive via a molecular screening assay, were subsequently amplified using VP4 and VP7 specific primers (Con2/Con3 and 1A/1B primer sets, respectively). The age range of patients investigated was from <1 year to 89 years. The resulting PCR products were cloned into TOPO10 PCR IV vector and sequenced to give the P- and G-type accordingly. All sequence data were subjected to BLAST analysis. Three different rotavirus types P[8]G1, P[8]G4, and P[8]G9 were identified. Types P[8]G1 and P[8]G9 were identified as circulating within the community, whereas the third type P[8]G4 was identified only in an elderly care outbreak. The identification of G9 rotaviruses supports evidence of emergence of the genotype on a global scale.

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There is a need to provide rapid, sensitive, and often high throughput detection of pathogens in diagnostic virology. Viral gastroenteritis is a serious health issue often leading to hospitalization in the young, the immunocompromised and the elderly. The common causes of viral gastroenteritis include rotavirus, norovirus (genogroups I and II), astrovirus, and group F adenoviruses (serotypes 40 and 41). This article describes the work‐up of two internally controlled multiplex, probe‐based PCR assays and reports on the clinical validation over a 3‐year period, March 2007 to February 2010. Multiplex assays were developed using a combination of TaqMan™ and minor groove binder (MGB™) hydrolysis probes. The assays were validated using a panel of 137 specimens, previously positive via a nested gel‐based assay. The assays had improved sensitivity for adenovirus, rotavirus, and norovirus (97.3% vs. 86.1%, 100% vs. 87.8%, and 95.1% vs. 79.5%, respectively) and also more specific for targets adenovirus, rotavirus, and norovirus (99% vs. 95.2%, 100% vs. 93.6%, and 97.9% vs. 92.3%, respectively). For the specimens tested, both assays had equal sensitivity and specificity for astrovirus (100%). Overall the probe‐based assays detected 16 more positive specimens than the nested gel‐based assay. Post‐introduction to the routine diagnostic service, a total of 9,846 specimens were processed with multiplex 1 and 2 (7,053 pediatric, 2,793 adult) over the 3‐year study period. This clinically validated, probe‐based multiplex testing algorithm allows highly sensitive and timely diagnosis of the four most prominent causes of viral gastroenteritis. J. Med. Virol. 83:1650–1656, 2011. © 2011 Wiley‐Liss, Inc.

Background: Immunofluorescence and virus culture are the main methods used to diagnose acute respiratory virus infections. Diagnosing these infections using nucleic acid amplification presents technical challenges, one of which is facilitating the different optimal annealing temperatures needed for each virus. To overcome this problem we developed a diagnostic molecular strip which combined a generic nested touchdown protocol with in-house primer master-mixes that could recognise 12 common respiratory viruses.

A prospective study of norovirus outbreaks in Ireland was carried out over a 1-year period from 1 October 2004 to 30 September 2005. Epidemiological and molecular data on norovirus outbreaks in the Republic of Ireland (ROI) and Northern Ireland (NI) were collected and combined in real time in a common database. Most reported outbreaks occurred in hospitals and residential institutions and person-to-person spread was the predominant mode of transmission. The predominant circulating norovirus strain was the GII.4-2004 strain with a small number of outbreaks due to GII.2. This study represents the first time that enhanced epidemiological and virological data on norovirus outbreaks in Ireland have been described. The link established between the epidemiological and virological institutions during the course of this study has been continued and the data is being used as a source of data for the Foodborne Viruses in Europe Network (DIVINE-NET).

Background: Detection of antigens, nucleic acids, and isolation of microbes depend on pre-analytical devices used for collection of specimens. Diagnostic sensitivity varies with the number of microbial targets released and protected in the transport system. Previously Flocked Swabs (FS) and universal transport medium at room temperature (UTM-RT) [Copan, Brescia, Italy] enhanced analytical sensitivity with PCR assays.Aims: To determine whether RV positivity rates are different when nasopharyngeal swabs (NPS) are collected by FS into UTM-RT to diagnose RV using antigen, cell culture and PCR assays.Methods: NPS (n=2883) collected with FS and UTM-RT, from 11/01/04 to 02/28/06 were compared to NPS collected with an M4-RT collection system from the same time frame the previous years. An aliquot of NPS was stored for PCR; then tested by DFA and shell vial culture or with 4 antigen tests for RSV, Flu A and B. NPS (n =261) were tested by PCR for Flu A/B and 375 for hMPV.Results: The 2883 NPS DFA/culture had 416 (15%) Flu A, 150 (5%) Flu B, 502 (18%) RSV, 42 (2%) Para 1-3, 78 (3%) Adenovirus; 101/868 hMPV (15%). Antigen tests had 121 RSV, 33 Flu A, 37 Flu B and 100 negatives. The PCR detected 102/261 Flu, 66/375 hMPV. All rates were higher than the previous year.Conclusions: NPS collected with FS in UTM-RT demonstrated higher positivity rates for each virus type with DFA/culture, rapid antigens and PCR. PCR assays for Flu A, B, and hMPV were more sensitive than DFA and culture.