Introduction of rotavirus vaccines into national immunization programs (NIPs) could result in strain selection due to vaccine-induced selective pressure. This study describes the distribution and ...diversity of rotavirus genotypes before and after rotavirus vaccine introduction into the Australian NIP. State-based vaccine selection facilitated a unique comparison of diversity in RotaTeq and Rotarix vaccine states.
From 1995 to 2015, the Australian Rotavirus Surveillance Program conducted genotypic analysis on 13051 rotavirus-positive samples from children <5 years of age, hospitalized with acute gastroenteritis. Rotavirus G and P genotypes were determined using serological and heminested multiplex reverse-transcription polymerase chain reaction assays.
G1P8 was the dominant genotype nationally in the prevaccine era (1995-2006). Following vaccine introduction (2007-2015), greater genotype diversity was observed with fluctuating genotype dominance. Genotype distribution varied based on the vaccine implemented, with G12P8 dominant in states using RotaTeq, and equine-like G3P8 and G2P4 dominant in states and territories using Rotarix.
The increased diversity and differences in genotype dominance observed in states using RotaTeq (G12P8), and in states and territories using Rotarix (equine-like G3P8 and G2P4), suggest that these vaccines exert different immunological pressures that influence the diversity of rotavirus strains circulating in Australia.
Rotavirus vaccine: a single birth dose? Barnes, Graeme L
The Lancet infectious diseases,
July 2018, 2018-07-00, 20180701, Letnik:
18, Številka:
7
Journal Article
Recenzirano
...lower gastric acid in newborns, and administration during the early stage of microbial gut colonisation, are likely to facilitate immunisation.3,4 Neonatal infection by the RV3 strain of rotavirus ...was shown in 1983 to protect against subsequent diarrhoea, although not against reinfection.5 In 1996, Velazquez and colleagues6 reported that children with one, two, or three previous infections had progressively lower risks of both subsequent infection and diarrhoea. A two-dose trial10 of RRV-TV in Ghana included a neonatal first dose. 48% of infants had a rotavirus IgA response to the first dose, which increased to 56% after the second dose. ...some evidence supports the idea that some kind of immunological response is happening after one dose of rotavirus vaccine at birth. Surveillance after natural neonatal RV3 infection suggests that one birth dose could be enough.7 If it is shown to be adequately protective, easier access to children and lower costs of vaccine production and distribution will improve vaccination coverage—and the fear of intussusception will be lessened.
Abstract
Background
Rotavirus is a major cause of gastroenteritis in children <5 years of age. The disease burden in older children, adults, and the elderly is underappreciated. This study describes ...rotavirus disease and genotypic diversity in the Australian population comprising children ≥5 years of age and adults.
Methods
Rotavirus positive fecal samples were collected from laboratories Australia-wide participating in the Australian Rotavirus Surveillance Program between 2010 and 2018. Rotavirus samples were genotyped using a heminested multiplex reverse-transcription polymerase chain reaction. Notification data from the National Notifiable Diseases Surveillance System were also analyzed.
Results
Rotavirus disease was highest in children aged 5–9 years and adults ≥85 years. G2P4 was the dominant genotype in the population ≥5 years of age. Genotype distribution fluctuated annually and genotypic diversity varied among different age groups. Geographical differences in genotype distribution were observed based on the rotavirus vaccine administered to infants <1 year of age.
Conclusions
This study revealed a substantial burden of rotavirus disease in the population ≥5 years of age, particularly in children 5–9 years and the elderly. This study highlights the continued need for rotavirus surveillance across the population, despite the implementation of efficacious vaccines.
This study describes rotavirus disease and genotypic diversity in the Australian population aged ≥5 years. A substantial burden was identified; particularly in children 5–9 years and the elderly. Genotype distribution and diversity fluctuated annually and varied among age groups.
BACKGROUND:Rotavirus vaccines, RotaTeq and Rotarix, were introduced into the Australian National Immunization Program on July 1, 2007. The simultaneous introduction in different Australian states and ...territories provides a unique opportunity to compare the affect of each vaccine on the types of circulating rotavirus strains. This report describes the rotavirus genotypes responsible for the hospitalization of children during the first 2-year period after vaccine introduction.
METHODS:A total of 764 rotavirus-associated diarrheal cases were collected from children presenting to hospital in 10 Australian centers. Rotavirus genotype was determined using reverse transcription polymerase chain reaction assays.
RESULTS:G1P8 was the dominant genotype nationally (52%), followed by G2P4 (19.8%), G9P8 (12.2%), and G3P8 (11%). Differences in the prevalence rates of G2P4 and G3P8 were seen in the various states. G2P4 strains were more prevalent in states using Rotarix, whereas G3P8 strains were more prevalent in states using RotaTeq.
CONCLUSIONS:Differences in rotavirus genotypes were observed across Australia, which suggest that different immune pressures are exerted by the different vaccines, but do not necessarily imply lack of protection by either vaccine. These differences may simply be related to the variation that can occur because of natural annual fluctuation in rotavirus strain prevalence.
Severe diarrhea from rotavirus remains an important cause of illness in infants. In this trial, investigators in Indonesia assessed the potential benefit of a neonatal rotavirus vaccine.
Indigenous children living in arid Central Australia experience frequent outbreaks of rotavirus gastroenteritis. A widespread outbreak of G9 rotavirus infection occurred several months after ...introduction of the RIX4414 rotavirus vaccine. We performed a retrospective case-control study to determine vaccine efficacy during the outbreak. Two doses provided an estimated vaccine efficacy of 77.7% (95% confidence interval, 40.2%-91.7%) against hospitalization for gastroenteritis. Vaccine efficacy was 84.5% (95% confidence interval, 23.4%-96.9%) against confirmed cases of rotavirus infection. Vaccination was effective in this high-burden setting.
Summary Background Despite the success of rotavirus vaccines, suboptimal vaccine efficacy in regions with a high burden of disease continues to present a challenge to worldwide implementation. A ...birth dose strategy with a vaccine developed from an asymptomatic neonatal rotavirus strain has the potential to address this challenge and provide protection from severe rotavirus disease from birth. Methods This phase 2a randomised, double-blind, three-arm, placebo-controlled safety and immunogenicity trial was undertaken at a single centre in New Zealand between Jan 13, 2012, and April 17, 2014. Healthy, full-term (≥36 weeks gestation) babies, who weighed at least 2500 g, and were 0–5 days old at the time of randomisation were randomly assigned (1:1:1; computer-generated; telephone central allocation) according to a concealed block randomisation schedule to oral RV3-BB vaccine with the first dose given at 0–5 days after birth (neonatal schedule), to vaccine with the first dose given at about 8 weeks after birth (infant schedule), or to placebo. The primary endpoint was cumulative vaccine take (serum immune response or stool shedding of vaccine virus after any dose) after three doses. The immunogenicity analysis included all randomised participants with available outcome data. This trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12611001212943. Findings 95 eligible participants were randomised, of whom 89 were included in the primary analysis. A cumulative vaccine take was detected in 27 (90%) of 30 participants in the neonatal schedule group after three doses of RV3-BB vaccine compared with four (13%) of 32 participants in the placebo group (difference in proportions 0·78, 95% CI 0·55–0·88; p<0·0001). 25 (93%) of 27 participants in the infant schedule group had a cumulative vaccine take after three doses compared with eight (25%) of 32 participants in the placebo group (difference in proportions 0·68, 0·44–0·81; p<0·0001). A serum IgA response was detected in 19 (63%) of 30 participants and 20 (74%) of 27 participants, and stool shedding of RV3-BB was detected in 21 (70%) of 30 participants and 21 (78%) of 27 participants in the neonatal and infant schedule groups, respectively. The frequency of solicited and unsolicited adverse events was similar across the treatment groups. RV3-BB vaccine was not associated with an increased frequency of fever or gastrointestinal symptoms compared with placebo. Interpretation RV3-BB vaccine was immunogenic and well tolerated when given as a three-dose neonatal or infant schedule. A birth dose strategy of RV3-BB vaccine has the potential to improve the effectiveness and implementation of rotavirus vaccines. Funding Australian National Health and Medical Research Council, the New Zealand Health Research Council, and the Murdoch Childrens Research Institute.
Abstract
The CGIAR crop improvement (CI) programs, unlike commercial CI programs, which are mainly geared to profit though meeting farmers’ needs, are charged with meeting multiple objectives with ...target populations that include both farmers and the community at large. We compiled the opinions from >30 experts in the private and public sector on key strategies, methodologies, and activities that could the help CGIAR meet the challenges of providing farmers with improved varieties while simultaneously meeting the goals of: (i) nutrition, health, and food security; (ii) poverty reduction, livelihoods, and jobs; (iii) gender equality, youth, and inclusion; (iv) climate adaptation and mitigation; and (v) environmental health and biodiversity. We review the crop improvement processes starting with crop choice, moving through to breeding objectives, production of potential new varieties, selection, and finally adoption by farmers. The importance of multidisciplinary teams working towards common objectives is stressed as a key factor to success. The role of the distinct disciplines, actors, and their interactions throughout the process from crop choice through to adoption by farmers is discussed and illustrated.
This document arose from the urgent need to join forces (across nations and research disciplines) and stand together to improve the prospects for the most vulnerable population on the globe whose well-being depends on agricultural production. Here, we learn from the past, and draft future strategic guidelines that will facilitate efforts of the CGIAR institutions (https://www.cgiar.org/) to enhance the livelihoods of the less privileged through crop improvement.
Abstract This study documents rotavirus strains causing severe disease in Australian children during the pre-vaccine era. During the period 1997–2007, rotavirus strains from national multi-centre ...hospital-based surveillance in Australia were analysed for G and P types. G1P8 was the dominant genotype identified during the 11-year study, with intermittent peaks associated with genotypes G2P4, G3P8 and G9P8. The results provide baseline information of the G and P genotypes causing disease in Australian children, and highlight the unpredictable changes in genotype incidence that can occur on both a local and national level. To be optimally effective, rotavirus vaccines must prevent disease caused by all common rotavirus genotypes.
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