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Objective: Rare coexistence of disease or pathology Background: Infectious diarrheal illnesses such as rotavirus gastroenteritis are significant contributors to childhood morbidity and mortality, especially in low socio-demographic index regions. Major advances in addressing this issue include sanitation and clean water initiatives, as well as rotavirus immunization. In Australia, a robust vaccination program has significantly reduced childhood rotavirus infections, leading to decreased hospitalizations and mortality. However, cases of adult rotavirus still occur, and although these adult patients usually do not require interventional management, it is possible for them to present critically unwell and require resuscitation. Case Report: A previously well 65-year-old man presented to the Emergency Department febrile and hypotensive with severe diarrhea attributed to rotavirus. Clinically, he presented with mixed hypovolemic and septic shock. Despite initial resuscitation, he had multiple severe acute end-organ complications, secondary to poor perfusion. He acquired an acute kidney injury, type-2 myocardial infarction, and ischemic hepatic injury. The mainstay of management was rapid fluid resuscitation, continuous renal replacement therapy, and monitoring in the Intensive Care Unit; however, it was crucial to empirically treat for other causes of shock. Conclusions: To the best of our knowledge, there is a scarcity of reports documenting the management of severe rotavirus gastroenteritis in adults. We recommend advising elderly patients to avoid contact with individuals with diarrheal illnesses, especially rotavirus gastroenteritis. Clinicians should also promote awareness regarding the potential severity of a disease that is typically managed conservatively, and be aware that intervention can be required in severe gastroenteritis. [ABSTRACT FROM AUTHOR]

Rotaviruses (RV) have a high prevalence in piggeries worldwide and are one of the major pathogens causing severe diarrhoea in young pigs. RV species A, B, and C have been linked to piglet diarrhoea in Australian pig herds, but their genetic diversity has not been studied in detail. Based on sequencing of the structural viral protein 7 (VP7) RVA G genotypes G3, G4 and G5, and RVC types G1, G3, G5, and G6 have been identified in Australian piggeries in previous studies. Although occurrence of RVB was reported in Australia in 1988, no further genetic analysis has been conducted. To improve health management decisions in Australian pig herds, more information on RV prevalence and genetic diversity is needed. Here, 243 enteric samples collected from 20 pig farms within Eastern Australia were analysed for the presence of RV in different age groups using a novel PCR‐based multiplex assay (Pork MultiPath™ enteric panel). RVA, RVB, and RVC were detected in 10, 14, and 14 farms, respectively. Further sequencing of VP7 in selected RV‐positive samples revealed G genotypes G2, G5, G9 (RVA), G6, G8, G14, G16, G20 (RVB), and G1, G3, G5, G6 (RVC) present. RVA was only detected in young (<10 weeks old) pigs whereas RVB and RVC were also detected in older animals (>11 weeks old). Interestingly, RVB and RVC G‐type occurrence differed between age groups. In conclusion, this study provides new insights on the prevalence and diversity of different RV species in pig herds of Eastern Australia whilst demonstrating the ability of the Pork MultiPath™ technology to accurately differentiate between these RV species. [ABSTRACT FROM AUTHOR]

Young pigeon disease syndrome (YPDS) is characterized as a seasonally occurring, acute and primarily enteric medical condition of mainly juvenile domestic pigeons (Columba livia) with highly variable mortality reaching more than 50%. Although the syndrome has been known in Europe for almost three decades, its aetiology remains largely obscure. Recently, a previously unknown pigeon‐associated clade of Rotavirus A (RVA) genotype G18P[17] was detected in Europe and Australia in association with fatal diseases resembling YPDS. Here we show for the first time, that peroral inoculation of healthy juvenile homing pigeons with two genetically different cell culture isolates of RVA G18P[17] (106.3 foci‐forming units per bird) induces an acute and self‐limiting YPDS‐like disease in all infected birds. Clinical signs included regurgitation, diarrhoea, congested crops, anorexia and weight loss, as described for naturally RVA‐infected pigeons. In agreement with the original outbreaks, RVA isolate DR‐7 induced more pronounced clinical signs as compared to isolate DR‐5, indicating strain‐dependent virulence factors to contribute to variable disease outcomes observed in the field. All inoculated birds developed rotavirus‐reactive antibodies starting at seven days after inoculation. High levels of viral RNA and infectious virus were detectable in cloacal swabs and faecal samples already three days after inoculation. While shedding of infectious virus subsided within few days, moderate viral RNA levels were still detectable in cloacal swabs, faeces, and tissue samples at the end of the experiment three weeks after inoculation. Histopathological analysis at this time point revealed inflammatory lesions in spleens and livers of pigeons from both infected groups. In summary, we fulfilled Henle‐Koch's postulates and confirmed RVA G18P[17] as a primary cause of YPDS‐like diseases in domestic pigeons. By establishing an infection model, we provide a crucial tool for future research, such as identification of transmission routes and establishing vaccination regimes. [ABSTRACT FROM AUTHOR]

• RV1 conferred 73% vaccine effectiveness against notified rotavirus infection. • RV5 conferred 82% vaccine effectiveness against notified rotavirus infection. • Both complete and incomplete courses of rotavirus vaccine conferred good protection. • Rotavirus VE was comparable among Indigenous and non-Indigenous children. Two rotavirus vaccines (RV1 and RV5) were included in the publicly funded National Immunisation Program in Australia from July 2007. The programme in Western Australia initially provided RV1 (at ages 2 and 4 months) and then switched to RV5 (at ages 2, 4 and 6 months) from July 2009. This retrospective case-control study was conducted to assess the effectiveness of rotavirus vaccine against laboratory confirmed and notified cases of rotavirus infection among children aged <5 years. Case-subjects were identified as vaccine-eligible children (born from 1 May 2007) who were notified as having rotavirus infection during the period 2009–2011. The control group was vaccine-eligible children notified as having Campylobacter or Salmonella infection during the same period. Individual rotavirus immunisation status was ascertained from a population-based immunisation register. Full-dose and partial-dose vaccine effectiveness (VE) were calculated for both vaccines using the adjusted odds ratio (OR) of vaccination for cases versus controls (VE = (1 − OR)*100%). Overall, 282 cases and 883 controls were included. The adjusted VE for a full course of either rotavirus vaccine was 72% (95% CI: 56–82) and 71% (95% CI: 50–84) for partial vaccination (one dose of RV1 or one/two doses of RV5). The VE for a complete 3-dose course of RV5 was 82% (95% CI: 59–92) and for a full 2-dose course of RV1 was 73% (95% CI: 55–83). RV1 and RV5 were both effective in preventing laboratory confirmed and notified rotavirus infections among children aged <5 years. Even incomplete courses of vaccination conferred good protection. [ABSTRACT FROM AUTHOR]

Cases of vomiting and diarrhoea were reported in racing pigeons in Western Australia in May, 2016. Morbidity and mortality rates were high. Similar clinical disease was seen in Victoria in December and by early 2017 had been reported in all states except the Northern Territory, in different classes of domestic pigeon–racing, fancy and meat bird–and in a flock of feral pigeons. Autopsy findings were frequently unremarkable; histological examination demonstrated significant hepatic necrosis as the major and consistent lesion, often with minimal inflammatory infiltration. Negative contrast tissue suspension and thin section transmission electron microscopy of liver demonstrated virus particles consistent with a member of the Reoviridae. Inoculation of trypsin-treated Vero, MDBK and MA-104 cell lines resulted in cytopathic changes at two days after infection. Next generation sequencing was undertaken using fresh liver samples and a previously undescribed group A rotavirus (genotype G18P[]) of avian origin was identified and the virus was isolated in several cell lines. A q-RT-PCR assay was developed and used to screen a wider range of samples, including recovered birds. Episodes of disease have continued to occur and to reoccur in previously recovered lofts, with variable virulence reported. This is the first report of a rotavirus associated with hepatic necrosis in any avian species. [ABSTRACT FROM AUTHOR]

The article discusses the effectiveness of live-attenuated oral rotavirus vaccines (ORVs) in high-income countries. It identifies rotaviruses as the leading cause of dehydrating acute gastroenteritis (AGE) in young children around the world. The effect of the shifting age-related epidemiology of infection on the efficacy of vaccination is discussed, as well as the obstacles to vaccination including cold-chain capacity, cost and product availability.

The article offers information about studies on rotavirus vaccine and rotavirus strains, which are often classified according to the two surface capsid proteins, such as G (VP7) and P (VP4), that induce neutralizing antibodies. Other information related to surveillance systems in medicine and the development of a vaccine is presented.

Changes in the prevalence of G2 rotavirus after vaccine introduction are an important issue. However, such changes in a given country should be interpreted in the global context over time. We determined 35 Japanese G2 sequences and compared them with 508 globally collected G2 sequences. The D96N substitution, a substitution known to be associated with an abrupt increase in G2 strains and antigenic changes, emerged in those strains that formed a nascent lineage outside of the currently predominant lineage (sublineage IVa). Further studies are warranted to monitor the potential of their global spread, since they also appeared in Europe and Australia. [ABSTRACT FROM AUTHOR]

Abstract: A range of laboratory methods is now available for the detection of norovirus, a major cause of gastroenteritis. Recently, a commercial immunochromatographic assay for norovirus detection, the RIDA®QUICK assay, has become available, but there is still only limited information on its efficacy. This study examined the sensitivity and specificity of the RIDA®QUICK assay, using faecal material received for testing in a major diagnostic/reference laboratory in Australia. The sensitivity of the assay was found to be 83% and the specificity was 100%. No false positive norovirus results were found and the assay did not cross-react with common faecal viruses such as rotavirus, astrovirus, sapovirus and adenovirus. The assay was less reliable for genogroup I (GI) noroviruses than for genogroup II (GII) noroviruses. Genotypes detected by the assay included GII.1, GII.2, GII.3, GII.4, GII.6 and GII.7. The assay failed to detect any GI specimens in the test group. Genotypes not detected included GI.4 and GI.6. The assay was simple and quick to perform. It is valuable in a point-of-care situation or as a backup in a laboratory where a rapid initial norovirus result is required. [Copyright &y& Elsevier]

Abstract: This study describes the characterisation of G8 rotavirus strains isolated from humans with acute gastroenteritis. Six G8 strains were detected in Australia between 2002 and 2008. Four were G8P[14] strains, one was G8P[8]+[14] and one was G8 P non-typeable. By polyacrylamide gel electrophoresis and enzyme immunoassay analysis, four G8 strains with visible RNA exhibited a long electropherotype and five G8 strains displayed subgroup I specificity. Sequence analysis of the VP7 gene indicated that the G8 strains exhibited the highest nucleotide and amino acid identity with a G8P[11] bovine rotavirus strain detected in Japan. VP4 sequence data of one G8P[14] strain revealed that the closest identity was to another human-bovine-like strain detected in Australia, MG6, a G6P[14] strain. The identification of G8 strains causing disease further extends the number of G8P[14] strains detected in Australian children, and indicates that there is a rare but ongoing presence of uncommon human strains within the community in Australia. [Copyright &y& Elsevier]

Abstract: Bovine rotavirus (BRV) has been detected in both dairy and beef cattle herds worldwide. Stool samples collected from calves in the Gippsland region of Victoria, Australia were screened to determine the presence of BRV. A total of 100 faecal samples were collected from calves with and without diarrhoea across three farms during 2004 and 2005. Group A BRV was detected in 26% of faecal samples (22 from diarrheic calves and four from asymptomatic calves). Genotyping analysis of rotavirus positive samples indicated that G6P[5] was the most prevalent genotype (38.5%) followed by G6P[5+11] (15.4%). G10P[11] and G6+G10P[5] were each detected at a rate of 7.7%, and G6+G10P[11] was found in a single sample (3.8%). Seven samples (26.9%) could not be G and/or P typed. Thirty percent of the BRV positive samples were mixed infections, indicating that individual calves were co-infected with more than one strain of rotavirus. The G6P[5] strains exhibited high VP7 identity (>97% amino acid identity) with B-60, a G6 strain identified in Victorian calves during 1988. A G10P[11] isolate was closely related (>97% amino acid identity in VP7 and VP4 proteins) to a Victorian G10P[11] strain (B-11) also identified during 1988. This study demonstrates that BRV is a contributing pathogen to diarrhoeal disease in Victorian calves, with sequence analysis suggesting long-term conservation of the VP7 protein over a 16-year period. [Copyright &y& Elsevier]

For centuries, acute diarrhea has been a major worldwide cause of death in young children, and until 1973, no infectious agents could be identified in about 80% of patients admitted to hospital with severe dehydrating diarrhea. In 1973 Ruth Bishop, Geoffrey Davidson, Ian Holmes, and Brian Ruck identified abundant particles of a ‘new’ virus (rotavirus) in the cytoplasm of mature epithelial cells lining duodenal villi and in feces, from such children admitted to the Royal Children's Hospital, Melbourne. Rotaviruses have now been shown to cause 40–50% of severe acute diarrhea in young children worldwide in both developing and developed countries, and > 600 000 young children die annually from rotavirus disease, predominantly in South-East Asia and sub-Saharan Africa. Longitudinal surveillance studies following primary infection in young children have shown that rotavirus reinfections are common. However the immune response that develops after primary infection is protective against severe symptoms on reinfection. This observation became the basis for development of live oral rotavirus vaccines. Two safe and effective vaccines are now licensed in 100 countries and in use in 17 countries (including Australia). Rotarix (GSK) is a single attenuated human rotavirus, representative of the most common serotype identified worldwide (G1P[8]). RotaTeq (Merck) is a pentavalent mixture of naturally attenuated bovine/human rotavirus reassortants representing G1, G2, G3, G4, and P(8) serotypes. Preliminary surveillance of the numbers of children requiring hospitalization for severe diarrhea, in USA, Brazil, and Australia, after introduction of these vaccines, encourages the hope that rotavirus infection need no longer be a threat to young children worldwide. [ABSTRACT FROM AUTHOR]

The article discusses the findings of research aimed at assessing the effect of Australia's infant rotavirus vaccination program on disease notifications. An analysis was made for data collected on rotavirus notifications and from Queensland Health laboratories from 2006-2008 prior to the July 2007 implementation of the infant rotavirus vaccination program. The research concludes that the vaccination program resulted in a 65 percent decline in notifications, and a 15 percent drop in laboratory tests in 2008.

Objectives: Oral rotavirus vaccines are expected to become available in Australia within the next 2 years. In light of evidence for an association between a rotavirus vaccine and intussusception, it is important to define the baseline epidemiology of intussusception in Australia and establish a system for intussusception surveillance in the immediate post-licensure period. This study reports on incidence and epidemiology of intussusception in Australia. Methods: Data were obtained from the Australian Institute of Health and Welfare on all patients with a discharge diagnosis of intussusception from public and private hospitals in each state and territory of Australia from 1994 to 2000. We examined age at presentation, sex, month and year of presentation, indigenous status and clinical outcomes. The incidence of intussusception was calculated and annual trends examined. Surveillance data on rotavirus gastroenteritis hospitalizations over the same time period were also obtained to compare seasonal patterns. Results: From 1994 to 2000, a 39% reduction in intussusception incidence in infants aged <1 year was observed in Australia (13.1/10 000 to 8.1/10 000; P < 0.001). The incidence of intussusception was lower in indigenous infants (3.3/10 000 <1 year) compared to non-indigenous infants (10.4/10 000 <1 year; P < 0.001). There was no association between the seasonality of rotavirus infection and intussusception. Only one of 12 deaths due to intussusception was reported in an infant <1 year. Conclusions: This study documents the epidemiology of intussusception in Australia from 1994 to 2000 and provides important baseline information for future rotavirus vaccines. A lower risk of intussusception was identified in indigenous compared to non-indigenous infants. [ABSTRACT FROM AUTHOR]

Background: Although rotavirus is a major cause of gastroenteritis in children, its role in adult gastroenteritis and the sensitivity of different methods for its detection in specimens collected from adults are less well understood. Objectives: (1) To examine the frequency and seasonality of rotavirus-associated gastroenteritis outbreaks in aged-care facilities in Victoria, Australia. (2) To determine rotavirus type in these outbreaks. (3) To determine whether other enteropathogenic agents are present in specimens from these outbreaks. (4) To examine the sensitivity of different methods (electron microscopy (EM), reverse transcription-polymerase chain reaction (RT-PCR), enzyme immunoassay (EIA) and latex agglutination (LA)) for the detection of rotavirus in specimens from adults. Study design: Specimens from gastroenteritis outbreaks in aged-care facilities forwarded to this laboratory for the years 1997–2000 were tested for enteropathogenic agents by various methods. Epidemiological, clinical and seasonal data from the rotavirus-positive outbreaks were analysed. Results: Rotavirus was detected by EM in 18 out of 29 individuals associated with seven out of 53 (13%) gastroenteritis outbreaks in aged-care facilities; norovirus was detected in 22 outbreaks (42%) and astrovirus in one outbreak (2%). No mixed viral infection was found in any outbreak. All rotaviruses were typed as Group A by RT-PCR. The rotaviruses in the seven outbreaks were G-typed as follows: G2 (three outbreaks), G4 (two outbreaks), G1 (one outbreak) and G9 (one outbreak). The rotavirus-associated outbreaks were concentrated in mid-winter to mid-spring. The relative sensitivities of the Group A rotavirus detection methods (for the 29 specimens tested) were EM (18), first-round RT-PCR (11), second-round PCR (19), EIA-visual (19), EIA-photometric (19) and LA (13). Conclusions: In Victoria, Australia, outbreaks of gastroenteritis associated with rotavirus are quite common in aged-care facilities. They involve Group A rotavirus and have a winter/spring seasonality. G-types G1, G2, G4 and G9 were all detected. EIA, second-round PCR and EM proved sensitive methods for rotavirus detection whereas first-round RT-PCR and LA did not. [Copyright &y& Elsevier]

Background: A widespread G2P[4] rotavirus epidemic in rural and remote Australia provided an opportunity to evaluate the performance of Rotarix and RotaTeq rotavirus vaccines, ten years after their incorporation into Australia's National Immunisation Program. Methods: We conducted a retrospective case-control analysis. Vaccine-eligible children with laboratory-confirmed rotavirus infection were identified from jurisdictional notifiable infectious disease databases and individually matched to controls from the national immunisation register, based on date of birth, Aboriginal status and location of residence. Results: 171 cases met the inclusion criteria; most were Aboriginal and/or Torres Strait Islander (80%) and the median age was 19 months. Of these cases, 65% and 25% were fully or partially vaccinated, compared to 71% and 21% of controls. Evidence that cases were less likely than controls to have received a rotavirus vaccine dose was weak, OR 0.79 (95% CI, 0.46–1.34). On pre-specified subgroup analysis, there was some evidence of protection among children <12 months (OR 0.48 [95% CI, 0.22–1.02]), and among fully vs. partially vaccinated children (OR 0.65 [95% CI, 0.42–1.01]). Conclusion: Despite the known effectiveness of rotavirus vaccination, a protective effect of either rotavirus vaccine during a G2P[4] outbreak in these settings among predominantly Aboriginal children was weak, highlighting the ongoing need for a more effective rotavirus vaccine and public health strategies to better protect Aboriginal children. [ABSTRACT FROM AUTHOR]

This article focuses on a research study on the epidemiology of intussusception in Australia, with respect to the use of an oral vaccine for rotavirus. Key findings and methodology of the study are discussed.