Molecular epidemiology and genetic evolution of the whole genome of G3P[8] human rotavirus in Wuhan, China, from 2000 through 2013.

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Yuan-Hong Wang

Full Text Available Rotaviruses are a major etiologic agent of gastroenteritis in infants and young children worldwide. Since the latter of the 1990s, G3 human rotaviruses referred to as "new variant G3" have emerged and spread in China, being a dominant genotype until 2010, although their genomic evolution has not yet been well investigated.The complete genomes of 33 G3P[8] human rotavirus strains detected in Wuhan, China, from 2000 through 2013 were analyzed. Phylogenetic trees of concatenated sequences of all the RNA segments and individual genes were constructed together with published rotavirus sequences.Genotypes of 11 gene segments of all the 33 strains were assigned to G3-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, belonging to Wa genogroup. Phylogenetic analysis of the concatenated full genome sequences indicated that all the modern G3P[8] strains were assigned to Cluster 2 containing only one clade of G3P[8] strains in the US detected in the 1970s, which was distinct from Cluster 1 comprising most of old G3P[8] strains. While main lineages of all the 11 gene segments persisted during the study period, different lineages appeared occasionally in RNA segments encoding VP1, VP4, VP6, and NSP1-NSP5, exhibiting various allele constellations. In contrast, only a single lineage was detected for VP7, VP2, and VP3 genes. Remarkable lineage shift was observed for NSP1 gene; lineage A1-2 emerged in 2007 and became dominant in 2008-2009 epidemic season, while lineage A1-1 persisted throughout the study period.Chinese G3P[8] rotavirus strains have evolved since 2000 by intra-genogroup reassortment with co-circulating strains, accumulating more reassorted genes over the years. This is the first large-scale whole genome-based study to assess the long-term evolution of common human rotaviruses (G3P[8] in an Asian country.

Rotavirus vaccines

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Kang G

2006-01-01

Full Text Available Rotavirus, the most common cause of severe diarrhea and a leading cause of mortality in children, has been a priority target for vaccine development for the past several years. The first rotavirus vaccine licensed in the United States was withdrawn because of an association of the vaccine with intussusception. However, the need for a vaccine is greatest in the developing world, because the benefits of preventing deaths due to rotavirus disease are substantially greater than the risk of intussusception. Early vaccines were based on animal strains. More recently developed and licenced vaccines are either animal-human reassortants or are based on human strains. In India, two candidate vaccines are in the development process, but have not yet reached efficacy trials. Many challenges regarding vaccine efficacy and safety remain. In addition to completing clinical evaluations of vaccines in development in settings with the highest disease burden and virus diversity, there is also a need to consider alternative vaccine development strategies.

Group A rotavirus gastroenteritis: post-vaccine era, genotypes and zoonotic transmission

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Luchs, Adriana; Timenetsky, Maria do Carmo Sampaio Tavares

2016-01-01

ABSTRACT This article provides a review of immunity, diagnosis, and clinical aspects of rotavirus disease. It also informs about the changes in epidemiology of diarrheal disease and genetic diversity of circulating group A rotavirus strains following the introduction of vaccines. Group A rotavirus is the major pathogen causing gastroenteritis in animals. Its segmented RNA genome can lead to the emergence of new or unusual strains in human populations via interspecies transmission and/or reassortment events. PMID:27462899

Diversity of group A rotavirus genes detected in the Triângulo Mineiro region, Minas Gerais, Brazil

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Ana Carolina Bernardes Dulgheroff

Full Text Available ABSTRACT Group A rotaviruses are the main causative agent of infantile gastroenteritis. The segmented nature of the viral genome allows reassortment of genome segments, which can generate genetic variants. In this study, we characterized the diversity of the VP7, VP4 (VP8*, VP6, NSP4, and NSP5 genes of the rotaviruses that circulated from 2005 to 2011 in the Triângulo Mineiro (TM region of Brazil. Samples with genotypes G2 (sublineages IVa-1 and IVa-3, G1 (sublineage I-A, G9 (lineage III, G12 (lineages II and III, G8 (lineage II, G3 (lineage III, P[4] (sublineages IVa and IVb, P[8] (sublineages P[8]-3.6, P[8]-3.3, and P[8]-3.1, I2 (lineage VII, E2 (lineages VI, XII, and X, and H2 (lineage III were identified. The associations found in the samples were G1, G9, or G12 with P[8]-I1-E1-H1; G2 or G8 with P[4]-I2-E2-H2; G12 with I3-E3-H6; and G3 with P[4]-I2-E3-H3 (previously unreported combination. Reassortment events in G2P[4] strains and an apparent pattern of temporal segregation within the lineages were observed. Five TM samples contained genes that exhibited high nucleotide and amino acid identities with strains of animal origin. The present study includes a period of pre- and post-introduction of rotavirus vaccination in all Brazilian territories, thereby serving as a basis for monitoring changes in the genetic constitution of rotaviruses. The results also contribute to the understanding of the diversity and evolution of rotaviruses in a global context.

Characterization of incompletely typed rotavirus strains from Guinea-Bissau: identification of G8 and G9 types and a high frequency of mixed infections

DEFF Research Database (Denmark)

Fischer, T.K.; Page, N.A.; Griffin, D.D.

2003-01-01

%, respectively, identical to other African G8 and G9 strains. Multiple G and/or P types were identified at a high frequency (59%), including two previously undescribed mixed infections, P[4]P[6], G2G8 and P[4]P[6], G2G9. These mixed infections most likely represent naturally occurring reassortance of rotavirus......] and P[6] primer binding sites were detected. These findings highlight the need for regular evaluation of the multiplex primer PCR method and typing primers. The high frequency of uncommon as well as reassortant rotavirus strains in countries where rotavirus is an important cause of child mortality...... underscores the need for extensive strain surveillance as a basis to develop appropriate rotavirus vaccine candidates....

A randomized Phase III clinical trial to assess the efficacy of a bovine-human reassortant pentavalent rotavirus vaccine in Indian infants.

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Kulkarni, Prasad S; Desai, Sajjad; Tewari, Tushar; Kawade, Anand; Goyal, Nidhi; Garg, Bishan Swarup; Kumar, Dinesh; Kanungo, Suman; Kamat, Veena; Kang, Gagandeep; Bavdekar, Ashish; Babji, Sudhir; Juvekar, Sanjay; Manna, Byomkesh; Dutta, Shanta; Angurana, Rama; Dewan, Deepika; Dharmadhikari, Abhijeet; Zade, Jagdish K; Dhere, Rajeev M; Fix, Alan; Power, Maureen; Uprety, Vidyasagar; Parulekar, Varsha; Cho, Iksung; Chandola, Temsunaro R; Kedia, Vikash K; Raut, Abhishek; Flores, Jorge

2017-10-27

Rotavirus is the most common cause of moderate-to-severe infant diarrhoea in developing countries, resulting in enormous morbidity, mortality, and economic burden. A bovine-human reassortant pentavalent rotavirus vaccine (BRV-PV) targeting the globally most common strains was developed in India and tested in a randomized, double-blind, placebo-controlled end-point driven Phase III efficacy clinical trial implemented at six sites across India. Infants 6 to 8weeks of age were randomized (1:1) to receive three oral doses of BRV-PV or placebo at 6, 10, and 14weeks of age along with routine vaccines. Home visit surveillance was conducted to detect severe rotavirus gastroenteritis (SRVGE) and safety outcomes until the children reached two years of age. A total of 3749 infants received BRV-PV while 3751 received placebo. At the time of the primary end-point (when the minimum number of cases needed for analysis were accrued) the vaccine efficacy against SRVGE was 36% (95% CI 11.7, 53.6, p=0.0067) in the per protocol (PP) analysis, and 41.9% (95% CI 21.1, 57.3, p=0.0005) in the intent to treat (ITT) analysis. Vaccine efficacy over the entire follow-up period (until children reached two years of age) was 39.5% (95% CI 26.7, 50, protavirus cases (VSRVGE, Vesikari score≥16) was 60.5% (95% CI 17.7, 81, p=0.0131) at the time of the primary analysis and 54.7% (95% CI 29.7, 70.8, p=0.0004) for the complete follow-period in the PP population. The incidence of solicited, unsolicited, and serious adverse events were similar in both the vaccine and placebo groups. Likewise, the number of intussusceptions and deaths were similar between both groups. Thus, BRV-PV is an effective, well tolerated and safe vaccine in Indian infants. (Trial registration: Clinical Trials.Gov [NCT 02133690] and Clinical Trial Registry of India [CTRI/2013/05/003667]). Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Clinical and Molecular Characteristics of Human Rotavirus G8P[8] Outbreak Strain, Japan, 2014.

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Kondo, Kenji; Tsugawa, Takeshi; Ono, Mayumi; Ohara, Toshio; Fujibayashi, Shinsuke; Tahara, Yasuo; Kubo, Noriaki; Nakata, Shuji; Higashidate, Yoshihito; Fujii, Yoshiki; Katayama, Kazuhiko; Yoto, Yuko; Tsutsumi, Hiroyuki

2017-06-01

During March-July 2014, rotavirus G8P[8] emerged as the predominant cause of rotavirus gastroenteritis among children in Hokkaido Prefecture, Japan. Clinical characteristics were similar for infections caused by G8 and non-G8 strains. Sequence and phylogenetic analyses suggest the strains were generated by multiple reassortment events between DS-1-like P[8] strains and bovine strains from Asia.

Prevention of rotavirus gastroenteritis in infants and children: rotavirus vaccine safety, efficacy, and potential impact of vaccines

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Aruna Chandran

2010-07-01

Full Text Available Aruna Chandran1, Sean Fitzwater1, Anjie Zhen2, Mathuram Santosham11Department of International Health, Division of Health Systems, 2Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USAAbstract: Rotavirus infection is the most common cause of severe gastroenteritis globally, with greater than 86% of deaths occurring in low-income and middle-income countries. There are two rotavirus vaccines currently licensed in the United States and prequalified by the World Health Organization. RV1 is a monovalent attenuated human rotavirus strain, given orally in two doses. RV5 is a pentavalent human-bovine reassortant rotavirus vaccine, given orally in three doses. A third rotavirus vaccine, LLV, is a lamb rotavirus strain given orally as a single dose, which is currently available only in China. RV1 and RV5 have been shown to be highly efficacious in developed countries, and initial results from trials in Africa and Asia are promising as well. At least three other vaccines are in development, which are being developed by manufacturers of developing countries. Further studies are needed to clarify issues including administration of oral rotavirus vaccines with breastfeeding and other oral vaccines, and alterations in dosing schedule. Using new data on global diarrheal burden, rotavirus is estimated to cause 390,000 deaths in children younger than 5 years. Should rotavirus vaccines be introduced in the routine immunization programs of all countries, a potential of 170,000 deaths could be prevented annually. The largest impact on mortality would be seen in low-income and middle-income countries, despite poor immunization coverage and lower efficacy. Therefore, international efforts are needed to ensure that rotavirus vaccines reach the populations with highest burden of rotavirus disease.Keywords: vaccination, mortality, rotavirus, gastroenteritis

Efficacy and safety of a pentavalent live human-bovine reassortant rotavirus vaccine (RV5) in healthy Chinese infants: A randomized, double-blind, placebo-controlled trial.

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Mo, Zhaojun; Mo, Yi; Li, Mingqiang; Tao, Junhui; Yang, Xu; Kong, Jilian; Wei, Dingkai; Fu, Botao; Liao, Xueyan; Chu, Jianli; Qiu, Yuanzheng; Hille, Darcy A; Nelson, Micki; Kaplan, Susan S

2017-10-13

A randomized, double-blind, placebo-controlled multicenter trial was conducted in healthy Chinese infants to assess the efficacy and safety of a pentavalent live human-bovine reassortant rotavirus vaccine (RotaTeq™, RV5) against rotavirus gastroenteritis (RVGE). 4040 participants aged 6-12weeks were enrolled and randomly assigned to either 3 oral doses of RV5 (n=2020) or placebo (n=2020), administered ∼4weeks apart. The participants also received OPV and DTaP in a concomitant or staggered fashion. The primary objective was to evaluate vaccine efficacy (VE) against naturally-occurring RVGE at least 14days following the third dose. Key secondary objectives included: VE against naturally-occurring severe RVGE and VE against severe and any-severity RVGE caused by rotavirus serotypes contained in the vaccine, occurring at least 14days after the third dose. All adverse events (AEs) were collected for 30days following each dose. Serious AEs (SAEs) and intussusception cases were collected during the entire study. (ClinicalTrials.gov registry: NCT02062385). VE against RVGE of any-severity caused by any serotype was 69.3% (95% CI: 54.5, 79.7). The secondary efficacy analysis showed an efficacy of: 78.9% (95% CI: 59.1, 90.1) against severe RVGE caused by any serotype; 69.9% (95% CI: 55.2, 80.3) and 78.9% (95% CI: 59.1, 90.1) against any-severity and severe RVGE caused by serotypes contained in the vaccine, respectively. Within 30days following any vaccination, 53.5% (1079/2015) and 53.3% (1077/2019) of participants reported at least one AE, and 5.8% (116/2015) and 5.7% (116/2019) reported SAEs in the vaccine and placebo groups, respectively. No SAEs were considered vaccine-related in recipients of RV5. Two intussusception cases were reported in recipients of RV5 who recovered after receiving treatment. Neither was considered vaccine-related. In Chinese infants, RV5 was efficacious against any-severity and severe RVGE caused by any serotype and generally well

Characterization of incompletely typed rotavirus strains from Guinea-Bissau: identification of G8 and G9 types and a high frequency of mixed infections

DEFF Research Database (Denmark)

Fischer, TK; Page, NA; Griffin, DD

2003-01-01

Among 167 rotavirus specimens collected from young children in a suburban area of Bissau, Guinea-Bissau, from 1996 to 1998, most identifiable strains belonged to the uncommon P[6], G2 type and approximately 50% remained incompletely typed. In the present study, 76 such strains were further......%, respectively, identical to other African G8 and G9 strains. Multiple G and/or P types were identified at a high frequency (59%), including two previously undescribed mixed infections, P[4]P[6], G2G8 and P[4]P[6], G2G9. These mixed infections most likely represent naturally occurring reassortance of rotavirus......] and P[6] primer binding sites were detected. These findings highlight the need for regular evaluation of the multiplex primer PCR method and typing primers. The high frequency of uncommon as well as reassortant rotavirus strains in countries where rotavirus is an important cause of child mortality...

Human neonatal rotavirus vaccine (RV3-BB) targets rotavirus from birth

Science.gov (United States)

Thobari, Jarir At; Satria, Cahya Dewi; Handley, Amanda; Watts, Emma; Cowley, Daniel; Nirwati, Hera; Ackland, James; Standish, Jane; Justice, Frances; Byars, Gabrielle; Lee, Katherine J.; Barnes, Graeme L.; Bachtiar, Novilia S.; Icanervilia, Ajeng Viska; Boniface, Karen; Bogdanovic-Sakran, Nada; Pavlic, Daniel; Bishop, Ruth F.; Kirkwood, Carl D.; Buttery, Jim P.; Soenarto, Yati

2018-01-01

Background A birth dose strategy using a neonatal rotavirus vaccine to target early prevention of rotavirus disease may address remaining barriers to global vaccine implementation. Methods We conducted a randomized, placebo-controlled trial in Indonesia to evaluate the efficacy of an oral human neonatal rotavirus vaccine (RV3-BB) to prevent rotavirus gastroenteritis. Healthy newborns received three doses of RV3-BB administered in a neonatal schedule at 0-5 days, 8 and 14 weeks or infant schedule at 8, 14 and 18 weeks, or placebo. Laboratory-confirmed rotavirus gastroenteritis was graded using a modified Vesikari score. The primary analysis was efficacy against severe rotavirus gastroenteritis from two weeks after all doses to 18 months in the combined vaccine group (neonatal and infant schedule) compared with placebo. Results Vaccine efficacy against severe rotavirus gastroenteritis to 18 months was 63% in the combined vaccine group (95% CI 34, 80; p<0.001), 75% in the neonatal vaccine group (95% confidence interval [CI] 44, 91; p<0.001) and 51% in the infant vaccine group (95% CI 7, 76; p=0.03) in the per protocol analysis, with similar results in the intention-to-treat analysis. Vaccine efficacy to 12 months was 94% in the neonatal vaccine group (95%CI 56, 99; p=0.006). Vaccine take occurred in 78/83 (94%) in the neonatal vaccine group and 83/84 (99%) in the infant vaccine group. The vaccine was well tolerated, with similar incidence of adverse events in vaccine and placebo recipients. Conclusion RV3-BB was efficacious, immunogenic and well-tolerated when administered in a neonatal or infant schedule in Indonesia. PMID:29466164

Comparative analysis of pentavalent rotavirus vaccine strains and G8 rotaviruses identified during vaccine trial in Africa.

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Heylen, Elisabeth; Zeller, Mark; Ciarlet, Max; Lawrence, Jody; Steele, Duncan; Van Ranst, Marc; Matthijnssens, Jelle

2015-10-06

RotaTeqTM is a pentavalent rotavirus vaccine based on a bovine rotavirus genetic backbone in vitro reassorted with human outer capsid genes. During clinical trials of RotaTeqTM in Sub-Saharan Africa, the vaccine efficacy over a 2-year follow-up was lower against the genotypes contained in the vaccine than against the heterotypic G8P[6] and G8P[1] rotavirus strains of which the former is highly prevalent in Africa. Complete genome analyses of 43 complete rotavirus genomes collected during phase III clinical trials of RotaTeqTM in Sub-Saharan Africa, were conducted to gain insight into the high level of cross-protection afforded by RotaTeqTM against these G8 strains. Phylogenetic analysis revealed the presence of a high number of bovine rotavirus gene segments in these human G8 strains. In addition, we performed an in depth analysis on the individual amino acid level which showed that G8 rotaviruses were more similar to the RotaTeqTM vaccine than non-G8 strains. Because RotaTeqTM possesses a bovine genetic backbone, the high vaccine efficacy against G8 strains might be partially explained by the fact that all these strains contain a complete or partial bovine-like backbone. Altogether, this study supports the hypothesis that gene segments other than VP7 and VP4 play a role in vaccine-induced immunity.

Rotavirus shedding following administration of RV3-BB human neonatal rotavirus vaccine.

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Cowley, Daniel; Boniface, Karen; Bogdanovic-Sakran, Nada; Kirkwood, Carl D; Bines, Julie E

2017-08-03

The RV3-BB human neonatal rotavirus vaccine aims to provide protection from severe rotavirus disease from birth. A phase IIa safety and immunogenicity trial was undertaken in Dunedin, New Zealand between January 2012 and April 2014. Healthy, full-term (≥ 36 weeks gestation) babies, who were 0-5 d old were randomly assigned (1:1:1) to receive 3 doses of oral RV3-BB vaccine with the first dose given at 0-5 d after birth (neonatal schedule), or the first dose given at about 8 weeks after birth (infant schedule), or to receive placebo (placebo schedule). Vaccine take (serum immune response or stool shedding of vaccine virus after any dose) was detected after 3 doses of RV3-BB vaccine in >90% of participants when the first dose was administered in the neonatal and infant schedules. The aim of the current study was to characterize RV3-BB shedding and virus replication following administration of RV3-BB in a neonatal and infant vaccination schedule. Shedding was defined as detection of rotavirus by VP6 reverse transcription polymerase chain reaction (RT-PCR) in stool on days 3-7 after administration of RV3-BB. Shedding of rotavirus was highest following vaccination at 8 weeks of age in both neonatal and infant schedules (19/30 and 17/27, respectively). Rotavirus was detected in stool on days 3-7, after at least one dose of RV3-BB, in 70% (21/30) of neonate, 78% (21/27) of infant and 3% (1/32) placebo participants. In participants who shed RV3-BB, rotavirus was detectable in stool on day 1 following RV3-BB administration and remained positive until day 4-5 after administration. The distinct pattern of RV3-BB stool viral load demonstrated using a NSP3 quantitative qRT-PCR in participants who shed RV3-BB, suggests that detection of RV3-BB at day 3-7 was the result of replication rather than passage through the gastrointestinal tract.

Detection of uncommon G3P[3] rotavirus A (RVA) strain in rat possessing a human RVA-like VP6 and a novel NSP2 genotype.

Science.gov (United States)

Ianiro, Giovanni; Di Bartolo, Ilaria; De Sabato, Luca; Pampiglione, Guglielmo; Ruggeri, Franco M; Ostanello, Fabio

2017-09-01

Rotavirus is one of the leading causes of acute gastroenteritis in infants and young children. RVAs infect not only humans but also a wide range of mammals including rats, which represent a reservoir of several other zoonotic pathogens. Due to the segmented nature of the RVA genome, animal RVA strains can easily adapt to the human host by reassortment with co-infecting human viruses. This study aims to detect and characterize RVA in the intestinal content of Italian sinantropic rats (Rattus rattus). Out of 40 samples examined following molecular approach, one resulted positive for RVA. The molecular characterization of VP1-4, 6 and 7, and NSP1-5 genes by sequencing revealed the genomic constellation G3-P[3]-I1-R11-C11-M10-A22-N18-T14-E18-H13. This uncommon genomic combination includes: the VP1-4,VP7, the NSP1, 3, 4 and 5 gene segments, closely related to those of RVA from rodents, the N18 novel genotype established for the NSP2 gene segment and the human Wa-like VP6 gene, suggesting interspecies reassortment. Copyright © 2017 Elsevier B.V. All rights reserved.

Human Neonatal Rotavirus Vaccine (RV3-BB) to Target Rotavirus from Birth.

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Bines, Julie E; At Thobari, Jarir; Satria, Cahya Dewi; Handley, Amanda; Watts, Emma; Cowley, Daniel; Nirwati, Hera; Ackland, James; Standish, Jane; Justice, Frances; Byars, Gabrielle; Lee, Katherine J; Barnes, Graeme L; Bachtiar, Novilia S; Viska Icanervilia, Ajeng; Boniface, Karen; Bogdanovic-Sakran, Nada; Pavlic, Daniel; Bishop, Ruth F; Kirkwood, Carl D; Buttery, Jim P; Soenarto, Yati

2018-02-22

A strategy of administering a neonatal rotavirus vaccine at birth to target early prevention of rotavirus gastroenteritis may address some of the barriers to global implementation of a rotavirus vaccine. We conducted a randomized, double-blind, placebo-controlled trial in Indonesia to evaluate the efficacy of an oral human neonatal rotavirus vaccine (RV3-BB) in preventing rotavirus gastroenteritis. Healthy newborns received three doses of RV3-BB, administered according to a neonatal schedule (0 to 5 days, 8 weeks, and 14 weeks of age) or an infant schedule (8 weeks, 14 weeks, and 18 weeks of age), or placebo. The primary analysis was conducted in the per-protocol population, which included only participants who received all four doses of vaccine or placebo within the visit windows, with secondary analyses performed in the intention-to-treat population, which included all participants who underwent randomization. Among the 1513 participants in the per-protocol population, severe rotavirus gastroenteritis occurred up to the age of 18 months in 5.6% of the participants in the placebo group (28 of 504 babies), in 1.4% in the neonatal-schedule vaccine group (7 of 498), and in 2.7% in the infant-schedule vaccine group (14 of 511). This resulted in a vaccine efficacy of 75% (95% confidence interval [CI], 44 to 91) in the neonatal-schedule group (PBill and Melinda Gates Foundation and others; Australian New Zealand Clinical Trials Registry number, ACTRN12612001282875 .).

On the preparation of fine V8C7-WC and V4C3-WC powders

CSIR Research Space (South Africa)

Osborne, C

1997-01-01

Full Text Available The aim of this work was to produce V8C7-WC and V4C3-WC powders with grain size between 1 and 2mu-m, as a first stage of the preparation of fine grained WC-VC-Co hardmetal. V8C7-WC powder was produced via two routes: starting from preformed V8C7...

Inmunogenicidad, inocuidad y eficacia de una vacuna tetravalente obtenida por recombinación genética de rotavirus aislados de monos rhesus y seres humanos en Belém, Brasil Immunogenicity, safety and efficacy of tetravalent rhesus-human, reassortant rotavirus vaccine in Belém, Brazil

Directory of Open Access Journals (Sweden)

A. C. Linhares

1998-05-01

son lo suficientemente alentadores para justificar que en países en desarrollo se hagan otros estudios de esta vacuna con una dosis mayor para tratar de mejorar su inmunogenicidad y eficacia.A tetravalent rhesus-human reassortant rotavirus (RRV-TV vaccine (4 x 10(4 plaque-forming units/dose was evaluated for safety, immunogenicity and efficacy in a prospective, randomized, double-blind, placebo-controlled trial involving 540 Brazilian infants. Doses of vaccine or placebo were given at ages, 1, 3 and 5 months. No significant differences were noted in the occurrence of diarrhoea or vomiting in vaccine and placebo recipients following each dose. Low-grade fever occurred on days 3­5 in 2­3% of vaccinees after the first dose, but not after the second or third doses of vaccine. An IgA antibody response to rhesus rotavirus (RRV occurred in 58% of vaccinees and 33% of placebo recipients. Neutralizing antibody responses to individual serotypes did not exceed 20% when measured by fluorescent focus reduction, but exceeded 40% when assayed by plaque reduction neutralization. There were 91 cases of rotavirus diarrhoea among the 3-dose (vaccine or placebo recipients during two years of follow-up, 36 of them among children given the vaccine. Overall vaccine efficacy was 8% (P = 0.005 against any diarrhoea and 35% (P = 0.03 against any rotavirus diarrhoea. Protection during the first year of follow-up, when G serotype 1 rotavirus predominated, was 57% (P = 0.008, but fell to 12% in the second year. Similar results were obtained when analysis was restricted to episodes in which rotavirus was the only identified pathogen. There was a tendency for enhanced protection by vaccine against illness associated with an average of 6 or more stools per day. These results are sufficiently encouraging to warrant further studies of this vaccine in developing countries using a higher dosage in an attempt to improve its immunogenicity and efficacy.

Phase I trial of RV3-BB rotavirus vaccine: a human neonatal rotavirus vaccine.

Science.gov (United States)

Danchin, M; Kirkwood, C D; Lee, K J; Bishop, R F; Watts, E; Justice, F A; Clifford, V; Cowley, D; Buttery, J P; Bines, J E

2013-05-28

RV3 is a human neonatal rotavirus strain (G3P[6]) that has been associated with asymptomatic neonatal infection and replicates well in the infant gut. RV3-BB rotavirus vaccine has been developed as a rotavirus vaccine candidate for administration at birth. A single-centre, double-blind, randomised placebo-controlled Phase I study evaluated the safety and tolerability of a single oral dose of the second generation RV3-BB rotavirus vaccine (8.3×10(6)FFU/mL) in 20 adults, 20 children and 20 infants (10 vaccine and 10 placebo per age cohort). Vaccine take was defined as seroconversion (a 3-fold increase in serum anti-rotavirus IgA or serum neutralising antibody (SNA) from baseline at day 28 post-dose) or evidence of RV3-BB viral replication in the faeces by RT-PCR analysis 3-6 days post-vaccination. RV3-BB presence was confirmed by sequence analysis. The RV3-BB vaccine was well tolerated in all participants, with no pattern of adverse events shown to be associated with the study vaccine. In the infant cohort, vaccine take was demonstrated in 8/9 infants following a single dose of vaccine compared with 2/7 placebo recipients. In the infant vaccine group, 5/9 infants exhibited either IgA or SNA seroconversion and 7/9 infants had evidence of RV3-BB replication on days 3-6, compared with 2/7 infants who seroconverted and 0/10 infants with evidence of replication in the placebo group. Two infants in the placebo group had serological evidence of a rotavirus infection within the 28-day study period: one demonstrated an IgA and the other an SNA response, with wild-type virus replication detected in another infant. A single dose of RV3-BB rotavirus vaccine was well tolerated in adults, children and infants. Most infants (8/9) who received RV3-BB demonstrated vaccine take following a single dose. These data support progression of RV3-BB to Phase II immunogenicity and efficacy trials. Copyright © 2013 Elsevier Ltd. All rights reserved.

Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses

OpenAIRE

Lee Chang-Won; Al-Natour Mohammad Q; Yassine Hadi M; Saif Yehia M

2007-01-01

1. Abstract The triple reassortant H3N2 viruses were isolated for the first time from pigs in 1998 and are known to be endemic in swine and turkey populations in the United States. In 2004, we isolated two H3N2 triple reassortant viruses from two turkey breeder flocks in Ohio and Illinois. Infected hens showed no clinical signs, but experienced a complete cessation of egg production. In this study, we evaluated three triple reassortant H3N2 isolates of turkey origin and one isolate of swine o...

Potential safety issues and other factors that may affect the introduction and uptake of rotavirus vaccines

Science.gov (United States)

Aliabadi, N.; Tate, J.E.; Parashar, U.D.

2018-01-01

Rotavirus vaccines have demonstrated significant impact in reducing the burden of morbidity and mortality from childhood diarrhoea in countries that have implemented routine vaccination to date. Despite this success, in many countries, rotavirus vaccine coverage remains lower than that of other routine childhood vaccines. Several issues may potentially affect vaccine uptake, namely safety concerns related to intussusception with consequent age restrictions on rotavirus vaccination, contamination with porcine circovirus, vaccine-derived reassortant strains and hospitalization in newborn nurseries at time of administration of live oral rotavirus vaccine. In addition to these safety concerns, other factors may also affect uptake, including lower vaccine efficacy in the developing world, potential emergence of strains escaping from vaccine protection resulting in lower overall impact of a vaccination programme and sustainable vaccine financing. Although further work is needed to address some of these concerns, global policy bodies have reaffirmed that the benefits of rotavirus vaccination outweigh the risks, and vaccine use is recommended globally. PMID:27129416

Potential safety issues and other factors that may affect the introduction and uptake of rotavirus vaccines.

Science.gov (United States)

Aliabadi, N; Tate, J E; Parashar, U D

2016-12-01

Rotavirus vaccines have demonstrated significant impact in reducing the burden of morbidity and mortality from childhood diarrhoea in countries that have implemented routine vaccination to date. Despite this success, in many countries, rotavirus vaccine coverage remains lower than that of other routine childhood vaccines. Several issues may potentially affect vaccine uptake, namely safety concerns related to intussusception with consequent age restrictions on rotavirus vaccination, contamination with porcine circovirus, vaccine-derived reassortant strains and hospitalization in newborn nurseries at time of administration of live oral rotavirus vaccine. In addition to these safety concerns, other factors may also affect uptake, including lower vaccine efficacy in the developing world, potential emergence of strains escaping from vaccine protection resulting in lower overall impact of a vaccination programme and sustainable vaccine financing. Although further work is needed to address some of these concerns, global policy bodies have reaffirmed that the benefits of rotavirus vaccination outweigh the risks, and vaccine use is recommended globally. Published by Elsevier Ltd.

Characterization of incompletely typed rotavirus strains from Guinea-Bissau: identification of G8 and G9 types and a high frequency of mixed infections

International Nuclear Information System (INIS)

Fischer, T.K.; Page, N.A.; Griffin, D.D.; Eugen-Olsen, J.; Pedersen, A.G.; Valentiner-Branth, P.; Moelbak, K.; Sommerfelt, H.; Nielsen, N. Munk

2003-01-01

Among 167 rotavirus specimens collected from young children in a suburban area of Bissau, Guinea-Bissau, from 1996 to 1998, most identifiable strains belonged to the uncommon P[6], G2 type and approximately 50% remained incompletely typed. In the present study, 76 such strains were further characterized. Due to interprimer interaction during the standard multiplex PCR approach, modifications of this procedure were implemented. The modified analyses revealed a high frequency of G2, G8, and G9 genotypes, often combined with P[4] and/or P[6]. The Guinean G8 and G9 strains were 97 and 98%, respectively, identical to other African G8 and G9 strains. Multiple G and/or P types were identified at a high frequency (59%), including two previously undescribed mixed infections, P[4]P[6], G2G8 and P[4]P[6], G2G9. These mixed infections most likely represent naturally occurring reassortance of rotavirus strains. Detection of such strains among the previously incompletely typed strains indicates a potential underestimation of mixed infections, if only a standard multiplex PCR procedure is followed. Furthermore cross-priming of the G3 primer with the G8 primer binding site and silent mutations at the P[4] and P[6] primer binding sites were detected. These findings highlight the need for regular evaluation of the multiplex primer PCR method and typing primers. The high frequency of uncommon as well as reassortant rotavirus strains in countries where rotavirus is an important cause of child mortality underscores the need for extensive strain surveillance as a basis to develop appropriate rotavirus vaccine candidates

Prevalence and characterization of rotaviruses in children hospitalized for diarrheal disease in a tertiary care hospital, Pune

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Sae Satish Pol

2017-01-01

Full Text Available Background: Diarrhoea remains the second most common cause of death among children below 5 years globally. Among various enteric pathogens, rotavirus appears to be the most important aetiological agent of acute gastroenteritis in infants and young children. Increased understanding of epidemiology of rotavirus infections is needed to improve the vaccine efficacy. Aim: This study aims to determine prevalence rotavirus infection and prevalent circulating strains of rotavirus in and around Pune. Setting and Design: Prospective hospital-based study. The study was approved by Institutional Ethical Committee. Materials and Methods: Stool samples (n = 100 were collected from children aged <5 years, hospitalised for acute diarrhoea in paediatric ward at a tertiary care hospital. Samples were subjected for rotavirus antigen capture ELISA. The viral RNA was subjected to multiplex reverse transcription polymerase chain reaction to amplify VP7 genotypes G1–G4, G8–G10 and G12 and VP4 genotypes P[4], P[6], P[8], P[9], P[10] and P[11]. Nontypable rotavirus strains were sequenced. Results: About 35% stool samples were positive for rotavirus antigen by ELISA. G9P[4] (28.6% was found to be the most prevalent rotavirus strain. The detection of emerging strain G12P[6] (14.3% and rare reassortant strain G9P[4] was the significant finding. Conclusion: Genotypes found in circulation are not present in the currently used vaccine. Thus, an emergence of newer genotypes over a period calls for the continued surveillance and genomic characterisation of rotaviruses to improve the vaccine efficacy.

Fitness cost of reassortment in human influenza.

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Mara Villa

2017-11-01

Full Text Available Reassortment, which is the exchange of genome sequence between viruses co-infecting a host cell, plays an important role in the evolution of segmented viruses. In the human influenza virus, reassortment happens most frequently between co-existing variants within the same lineage. This process breaks genetic linkage and fitness correlations between viral genome segments, but the resulting net effect on viral fitness has remained unclear. In this paper, we determine rate and average selective effect of reassortment processes in the human influenza lineage A/H3N2. For the surface proteins hemagglutinin and neuraminidase, reassortant variants with a mean distance of at least 3 nucleotides to their parent strains get established at a rate of about 10-2 in units of the neutral point mutation rate. Our inference is based on a new method to map reassortment events from joint genealogies of multiple genome segments, which is tested by extensive simulations. We show that intra-lineage reassortment processes are, on average, under substantial negative selection that increases in strength with increasing sequence distance between the parent strains. The deleterious effects of reassortment manifest themselves in two ways: there are fewer reassortment events than expected from a null model of neutral reassortment, and reassortant strains have fewer descendants than their non-reassortant counterparts. Our results suggest that influenza evolves under ubiquitous epistasis across proteins, which produces fitness barriers against reassortment even between co-circulating strains within one lineage.

Fitness cost of reassortment in human influenza.

Science.gov (United States)

Villa, Mara; Lässig, Michael

2017-11-01

Reassortment, which is the exchange of genome sequence between viruses co-infecting a host cell, plays an important role in the evolution of segmented viruses. In the human influenza virus, reassortment happens most frequently between co-existing variants within the same lineage. This process breaks genetic linkage and fitness correlations between viral genome segments, but the resulting net effect on viral fitness has remained unclear. In this paper, we determine rate and average selective effect of reassortment processes in the human influenza lineage A/H3N2. For the surface proteins hemagglutinin and neuraminidase, reassortant variants with a mean distance of at least 3 nucleotides to their parent strains get established at a rate of about 10-2 in units of the neutral point mutation rate. Our inference is based on a new method to map reassortment events from joint genealogies of multiple genome segments, which is tested by extensive simulations. We show that intra-lineage reassortment processes are, on average, under substantial negative selection that increases in strength with increasing sequence distance between the parent strains. The deleterious effects of reassortment manifest themselves in two ways: there are fewer reassortment events than expected from a null model of neutral reassortment, and reassortant strains have fewer descendants than their non-reassortant counterparts. Our results suggest that influenza evolves under ubiquitous epistasis across proteins, which produces fitness barriers against reassortment even between co-circulating strains within one lineage.

Rotavirus specific maternal antibodies and immune response to RV3-BB neonatal rotavirus vaccine in New Zealand

Science.gov (United States)

Chen, Mee-Yew; Kirkwood, Carl D.; Bines, Julie; Cowley, Daniel; Pavlic, Daniel; Lee, Katherine J.; Orsini, Francesca; Watts, Emma; Barnes, Graeme; Danchin, Margaret

2017-01-01

ABSTRACT Background: Maternal antibodies, acquired passively via placenta and/or breast milk, may contribute to the reduced efficacy of oral rotavirus vaccines observed in children in developing countries. This study aimed to investigate the effect of rotavirus specific maternal antibodies on the serum IgA response or stool excretion of vaccine virus after any dose of an oral rotavirus vaccine, RV3-BB, in parallel to a Phase IIa clinical trial conducted at Dunedin Hospital, New Zealand. At the time of the study rotavirus vaccines had not been introduced in New Zealand and the burden of rotavirus disease was evident. Methods: Rotavirus specific IgG and serum neutralizing antibody (SNA) levels in cord blood and IgA levels in colostrum and breast milk samples collected ∼4 weeks, ∼20 weeks and ∼28 weeks after birth were measured. Infants were randomized to receive the first dose of vaccine at 0–5 d (neonatal schedule) or 8 weeks (infant schedule). Breast feeding was with-held for 30 minutes before and after vaccine administration. The relationship between rotavirus specific IgG and SNA levels in cord blood and IgA in colostrum and breast milk at the time of first active dose of RV3-BB vaccine and level of IgA response and stool excretion after 3 doses of vaccine was assessed using linear and logistic regression. Results: Forty infants received 3 doses of RV3-BB rotavirus vaccine and were included in the analysis of the neonatal and infant groups. Rotavirus specific IgA in colostrum (neonatal schedule group) and breast milk at 4 weeks (infant schedule group) was identified in 14/21 (67%) and 14/17 (82%) of infants respectively. There was little evidence of an association between IgA in colostrum or breast milk IgA at 4 weeks, or between cord IgG or SNA level, and IgA response or stool excretion after 3 doses of RV3-BB, or after one dose (neonatal schedule) (all p>0.05). Conclusions: The level of IgA in colostrum or breast milk and level of placental Ig

Rotavirus specific maternal antibodies and immune response to RV3-BB neonatal rotavirus vaccine in New Zealand.

Science.gov (United States)

Chen, Mee-Yew; Kirkwood, Carl D; Bines, Julie; Cowley, Daniel; Pavlic, Daniel; Lee, Katherine J; Orsini, Francesca; Watts, Emma; Barnes, Graeme; Danchin, Margaret

2017-05-04

Maternal antibodies, acquired passively via placenta and/or breast milk, may contribute to the reduced efficacy of oral rotavirus vaccines observed in children in developing countries. This study aimed to investigate the effect of rotavirus specific maternal antibodies on the serum IgA response or stool excretion of vaccine virus after any dose of an oral rotavirus vaccine, RV3-BB, in parallel to a Phase IIa clinical trial conducted at Dunedin Hospital, New Zealand. At the time of the study rotavirus vaccines had not been introduced in New Zealand and the burden of rotavirus disease was evident. Rotavirus specific IgG and serum neutralizing antibody (SNA) levels in cord blood and IgA levels in colostrum and breast milk samples collected ∼4 weeks, ∼20 weeks and ∼28 weeks after birth were measured. Infants were randomized to receive the first dose of vaccine at 0-5 d (neonatal schedule) or 8 weeks (infant schedule). Breast feeding was with-held for 30 minutes before and after vaccine administration. The relationship between rotavirus specific IgG and SNA levels in cord blood and IgA in colostrum and breast milk at the time of first active dose of RV3-BB vaccine and level of IgA response and stool excretion after 3 doses of vaccine was assessed using linear and logistic regression. Forty infants received 3 doses of RV3-BB rotavirus vaccine and were included in the analysis of the neonatal and infant groups. Rotavirus specific IgA in colostrum (neonatal schedule group) and breast milk at 4 weeks (infant schedule group) was identified in 14/21 (67%) and 14/17 (82%) of infants respectively. There was little evidence of an association between IgA in colostrum or breast milk IgA at 4 weeks, or between cord IgG or SNA level, and IgA response or stool excretion after 3 doses of RV3-BB, or after one dose (neonatal schedule) (all p>0.05). The level of IgA in colostrum or breast milk and level of placental IgG and SNA did not impact on the serum IgA response or

Reassortment Group A Rotavirus from Straw-colored Fruit Bat (Eidolon helvum)

Centers for Disease Control (CDC) Podcasts

2010-12-02

In this podcast, Dr. Mathew Esona of the Division of Viral Diseases at CDC describes the discovery of a unique Group A rotavirus isolated from fruit bats in Kenya.  Created: 12/2/2010 by National Center for Emerging and Zoonotic Infectious Diseases, National Center for Immunization and Respiratory Diseases.   Date Released: 12/2/2010.

Further characterization of field strains of rotavirus from Nigeria VP4 genotype P6 most frequently identified among symptomatically infected children.

Science.gov (United States)

Adah, M I; Rohwedder, A; Olaleye, O D; Durojaiye, O A; Werchau, H

1997-10-01

Polymerase chain reaction was utilized to characterize the VP4 types of 39 Rotavirus field isolates from symptomatically infected children in Nigeria. Genotype P6 was identified most frequently, occurring in 41.03 per cent of the typed specimens. Genotype P8 was identified as the next most prevalent (33.3% per cent). Genotype p6 was widespread (68.75 per cent) among infected neonates in Southern Nigeria, but mix infection was more prevalent (70 per cent) among Northern Nigerian children. Four distinct strains were identified with four different P genotypes. Overall strain G1P8 predominated (22.22 per cent) followed by G3P6 (17.8 per cent). Strain G1P8 was most prevalent (70 per cent) among infants aged 3.1-9 months, but strain G3P6 was most frequently identified among neonates occurance of mix infection genotype demonstrates the potential for reassortment events among different rotavirus genogroups in Nigeria. The epidemiological implications of these findings for rotavirus vaccine development and application in the country were discussed.

Predicting Hotspots for Influenza Virus Reassortment

Science.gov (United States)

Gilbert, Marius; Martin, Vincent; Cappelle, Julien; Hosseini, Parviez; Njabo, Kevin Y.; Abdel Aziz, Soad; Xiao, Xiangming; Daszak, Peter; Smith, Thomas B.

2013-01-01

The 1957 and 1968 influenza pandemics, each of which killed ≈1 million persons, arose through reassortment events. Influenza virus in humans and domestic animals could reassort and cause another pandemic. To identify geographic areas where agricultural production systems are conducive to reassortment, we fitted multivariate regression models to surveillance data on influenza A virus subtype H5N1 among poultry in China and Egypt and subtype H3N2 among humans. We then applied the models across Asia and Egypt to predict where subtype H3N2 from humans and subtype H5N1 from birds overlap; this overlap serves as a proxy for co-infection and in vivo reassortment. For Asia, we refined the prioritization by identifying areas that also have high swine density. Potential geographic foci of reassortment include the northern plains of India, coastal and central provinces of China, the western Korean Peninsula and southwestern Japan in Asia, and the Nile Delta in Egypt. PMID:23628436

Rotavirus vaccines and vaccination in Latin America

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Linhares Alexandre C.

2000-01-01

Full Text Available Worldwide, rotaviruses account for more than 125 million cases of infantile gastroenteritis and nearly 1 million deaths per year, mainly in developing countries. Rather than other control measures, vaccination is most likely to have a major impact on rotavirus disease incidence. The peak incidence of rotavirus diarrhea occurs between 6 and 24 months of age. In developing countries, however, cases are not uncommon among children younger than 6 months. G serotypes 1 to 4 are responsible for most disease, but there are indications that in Brazil that G type 5 is of emerging epidemiological importance. Both homotypic and heterotypic responses are elicited during natural rotavirus infection, and the immunological response at the intestinal mucosal surface is probably the more consistent predictor of clinical immunity. With the primary objective of protecting children against life-threatening dehydrating diarrhea, many approaches to rotavirus vaccine development have been attempted. One vaccine, the tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV, was given licensing approval in the United States of America, introduced to the market, and later withdrawn. A number of studies have found better efficacy of RRV-TV in developed countries than in developing ones. Field trials with a 4 X 10(4 plaque-forming units (PFU preparation of RRV-TV have been carried out in two countries in Latin America, Brazil and Peru. Those trials yielded protective efficacy rates against all rotavirus diarrhea ranging from 18% to 35%. Data from a large catchment trial in Venezuela with a higher RRV-TV dose, of 4 X 10(5 PFU/dose, indicated an efficacy rate of 48% against all rotavirus diarrhea and 88% against severe rotavirus diarrhea. It appears that breast-feeding does not compromise the efficacy of RRV-TV if three doses of the vaccine are administered. Similarly, possible interference of oral poliovirus vaccine with the "take" of the rotavirus vaccine can be

Rotavirus vaccines and vaccination in Latin America

Directory of Open Access Journals (Sweden)

Alexandre C. Linhares

2000-11-01

Full Text Available Worldwide, rotaviruses account for more than 125 million cases of infantile gastroenteritis and nearly 1 million deaths per year, mainly in developing countries. Rather than other control measures, vaccination is most likely to have a major impact on rotavirus disease incidence. The peak incidence of rotavirus diarrhea occurs between 6 and 24 months of age. In developing countries, however, cases are not uncommon among children younger than 6 months. G serotypes 1 to 4 are responsible for most disease, but there are indications that in Brazil that G type 5 is of emerging epidemiological importance. Both homotypic and heterotypic responses are elicited during natural rotavirus infection, and the immunological response at the intestinal mucosal surface is probably the more consistent predictor of clinical immunity. With the primary objective of protecting children against life-threatening dehydrating diarrhea, many approaches to rotavirus vaccine development have been attempted. One vaccine, the tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV, was given licensing approval in the United States of America, introduced to the market, and later withdrawn. A number of studies have found better efficacy of RRV-TV in developed countries than in developing ones. Field trials with a 4 X 10(4 plaque-forming units (PFU preparation of RRV-TV have been carried out in two countries in Latin America, Brazil and Peru. Those trials yielded protective efficacy rates against all rotavirus diarrhea ranging from 18% to 35%. Data from a large catchment trial in Venezuela with a higher RRV-TV dose, of 4 X 10(5 PFU/dose, indicated an efficacy rate of 48% against all rotavirus diarrhea and 88% against severe rotavirus diarrhea. It appears that breast-feeding does not compromise the efficacy of RRV-TV if three doses of the vaccine are administered. Similarly, possible interference of oral poliovirus vaccine with the "take" of the rotavirus vaccine can be

Rotavirus specific maternal antibodies and immune response to RV3-BB neonatal rotavirus vaccine in New Zealand

OpenAIRE

Chen, Mee-Yew; Kirkwood, Carl D.; Bines, Julie; Cowley, Daniel; Pavlic, Daniel; Lee, Katherine J.; Orsini, Francesca; Watts, Emma; Barnes, Graeme; Danchin, Margaret

2017-01-01

Background: Maternal antibodies, acquired passively via placenta and/or breast milk, may contribute to the reduced efficacy of oral rotavirus vaccines observed in children in developing countries. This study aimed to investigate the effect of rotavirus specific maternal antibodies on the serum IgA response or stool excretion of vaccine virus after any dose of an oral rotavirus vaccine, RV3-BB, in parallel to a Phase IIa clinical trial conducted at Dunedin Hospital, New Zealand. At the time o...

Sequence analysis of the whole genomes of five African human G9 rotavirus strains.

Science.gov (United States)

Nyaga, Martin M; Jere, Khuzwayo C; Peenze, Ina; Mlera, Luwanika; van Dijk, Alberdina A; Seheri, Mapaseka L; Mphahlele, M Jeffrey

2013-06-01

The G9 rotaviruses are amongst the most common global rotavirus strains causing severe childhood diarrhoea. However, the whole genomes of only a few G9 rotaviruses have been fully sequenced and characterised of which only one G9P[6] and one G9P[8] are from Africa. We determined the consensus sequence of the whole genomes of five African human group A G9 rotavirus strains, four G9P[8] strains and one G9P[6] strain collected in Cameroon (central Africa), Kenya (eastern Africa), South Africa and Zimbabwe (southern Africa) in 1999, 2009 and 2010. Strain RVA/Human-wt/ZWE/MRC-DPRU1723/2009/G9P[8] from Zimbabwe, RVA/Human-wt/ZAF/MRC-DPRU4677/2010/G9P[8] from South Africa, RVA/Human-wt/CMR/1424/2009/G9P[8] from Cameroon and RVA/Human-wt/KEN/MRC-DPRU2427/2010/G9P[8] from Kenya were on a Wa-like genetic backbone and were genotyped as G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1. Strain RVA/Human-wt/ZAF/MRC-DPRU9317/1999/G9P[6] from South Africa was genotyped as G9-P[6]-I2-R2-C2-M2-A2-N1-T2-E2-H2. Rotavirus A strain MRC-DPRU9317 is the second G9 strain to be reported on a DS-1-like genetic backbone, the other being RVA/Human-wt/ZAF/GR10924/1999/G9P[6]. MRC-DPRU9317 was found to be a reassortant between DS-1-like (I2, R2, C2, M2, A2, T2, E2 and H2) and Wa-like (N1) genome segments. All the genome segments of the five strains grouped strictly according to their genotype Wa- or DS-1-like clusters. Within their respective genotypes, the genome segments of the three G9 study strains from southern Africa clustered most closely with rotaviruses from the same geographical origin and with those with the same G and P types. The highest nucleotide identity of genome segments of the study strains from eastern and central Africa regions on a Wa-like backbone was not limited to rotaviruses with G9P[8] genotypes only, they were also closely related to G12P[6], G8P[8], G1P[8] and G11P[25] rotaviruses, indicating a close inter-genotype relationship between the G9 and other rotavirus genotypes

Concentration of acrylamide in a polyacrylamide gel affects VP4 gene coding assignment of group A equine rotavirus strains with P[12] specificity

Science.gov (United States)

2010-01-01

Background It is universally acknowledged that genome segment 4 of group A rotavirus, the major etiologic agent of severe diarrhea in infants and neonatal farm animals, encodes outer capsid neutralization and protective antigen VP4. Results To determine which genome segment of three group A equine rotavirus strains (H-2, FI-14 and FI-23) with P[12] specificity encodes the VP4, we analyzed dsRNAs of strains H-2, FI-14 and FI-23 as well as their reassortants by polyacrylamide gel electrophoresis (PAGE) at varying concentrations of acrylamide. The relative position of the VP4 gene of the three equine P[12] strains varied (either genome segment 3 or 4) depending upon the concentration of acrylamide. The VP4 gene bearing P[3], P[4], P[6], P[7], P[8] or P[18] specificity did not exhibit this phenomenon when the PAGE running conditions were varied. Conclusions The concentration of acrylamide in a PAGE gel affected VP4 gene coding assignment of equine rotavirus strains bearing P[12] specificity. PMID:20573245

Group A rotavirus gastroenteritis: post-vaccine era, genotypes and zoonotic transmission.

Science.gov (United States)

Luchs, Adriana; Timenetsky, Maria do Carmo Sampaio Tavares

2016-01-01

ABSTRACTThis article provides a review of immunity, diagnosis, and clinical aspects of rotavirus disease. It also informs about the changes in epidemiology of diarrheal disease and genetic diversity of circulating group A rotavirus strains following the introduction of vaccines. Group A rotavirus is the major pathogen causing gastroenteritis in animals. Its segmented RNA genome can lead to the emergence of new or unusual strains in human populations via interspecies transmission and/or reassortment events.RESUMOEste artigo fornece uma revisão sobre imunidade, diagnóstico e aspectos clínicos da doença causada por rotavírus. Também aponta as principais mudanças no perfil epidemiológico da doença diarreica e na diversidade genética das cepas circulantes de rotavírus do grupo A, após a introdução vacinal. O rotavírus do grupo A é o principal patógeno associado à gastroenterite em animais. Seu genoma RNA segmentado pode levar ao surgimento de cepas novas ou incomuns na população humana, por meio de transmissão entre espécies e eventos de rearranjo.

Group A rotavirus in Brazilian bats: description of novel T15 and H15 genotypes.

Science.gov (United States)

Asano, Karen Miyuki; Gregori, Fabio; Hora, Aline Santana; Scheffer, Karin Corrêa; Fahl, Willian Oliveira; Iamamoto, Keila; Mori, Enio; Silva, Fernanda Dornelas Florentino; Taniwaki, Sueli Akemi; Brandão, Paulo Eduardo

2016-11-01

This study aimed to survey for group A rotaviruses (RVA) in bats from Brazil and to perform phylogenetic inferences for VP4, VP7, NSP3, NSP4 and NSP5 genes. RVA was found in 9.18 % (28/305) of tested samples. The partial genotype constellation of a Molossus molossus RVA strain was G3-P[3]-Ix-Rx-Cx-Mx-Ax-Nx-T3-E3-H6, and that of a Glossophaga soricina RVA strain was G20-P[x]-Ix-Rx-Cx-Mx-Ax-Nx-T15-Ex-H15. These findings demonstrate an important role of bats in RVA epidemiology and provide evidence of participation of bat RVA strains in interspecies transmission and reassortment events.

Lack of nonspecific protection against all-cause nonrotavirus gastroenteritis by vaccination with orally administered rotavirus vaccine.

Science.gov (United States)

Grant, Lindsay; Watt, James; Moulton, Lawrence; Weatherholtz, Robert; Reid, Raymond; Santosham, Mathuram; O'Brien, Katherine

2013-06-01

Acute gastroenteritis (AGE) is recognized as a global, common threat to child survival, especially in developing countries. Rotavirus, in particular, has been implicated as a leading cause of severe AGE; however, there are numerous other pathogens that also cause AGE. Several studies have demonstrated that oral vaccination against rotavirus has generated the unanticipated benefit of protecting against AGE caused by nonrotavirus pathogens. Safety and efficacy of the pentavalent bovine-human reassortant rotavirus vaccine were studied in multiple populations, including children of the Navajo and White Mountain Apache tribes in the southwestern United States. Stool specimens were collected from children with AGE and tested for rotavirus using an enzyme immunoassay. Analyses were conducted to detect the presence or absence of a vaccine effect on incidence, severity, and duration of AGE in which rotavirus was not detected. The majority of AGE (N = 558: 472 nonrotavirus vs 86 rotavirus) occurred between August 2002 and March 2004 among children ranging from ages 4 to 23 months. The incidence of nonrotavirus AGE was similar by vaccine groups with an incidence rate ratio of 1.07 (incidence rate ratio = vaccinated/unvaccinated, 95% confidence interval 0.89-1.29). The hazards of first, second, third, or any AGE in which rotavirus was not detected differed little by vaccination status (P > 0.05). Duration of symptoms and severity of nonrotavirus AGE were similar by vaccine group. There was no vaccine effect on frequency or severity of nonrotavirus AGE.

Sampling and analysis of inactive radioactive waste tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14 at ORNL

Energy Technology Data Exchange (ETDEWEB)

Sears, M.B.; Giaquinto, J.M.; Griest, W.H.; Pack, R.T.; Ross, T.; Schenley, R.L.

1995-12-01

The sampling and analysis of nine inactive liquid low-level waste (LLLW) tanks at the Oak Ridge National Laboratory (ORNL) are described-tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14. Samples of the waste tank liquids and sludges were analyzed to determine (1) the major chemical constituents, (2) the principal radionuclides, (3) metals listed on the US Environmental Protection Agency (EPA) Contract Laboratory Program Inorganic Target Analyte List, (4) organic compounds, and (5) some physical properties. The organic chemical characterization consisted of determinations of the EPA Contract Laboratory Program Target Compound List volatile and semivolatile compounds, pesticides, and polychlorinated biphenyis (PCBs). This report provides data (1) to meet requirements under the Federal Facility Agreement (FFA) for the Oak Ridge Reservation to characterize the contents of LLLW tanks which have been removed from service and (2) to support planning for the treatment and disposal of the wastes.

Sampling and analysis of inactive radioactive waste tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14 at ORNL

International Nuclear Information System (INIS)

Sears, M.B.; Giaquinto, J.M.; Griest, W.H.; Pack, R.T.; Ross, T.; Schenley, R.L.

1995-12-01

The sampling and analysis of nine inactive liquid low-level waste (LLLW) tanks at the Oak Ridge National Laboratory (ORNL) are described-tanks W-17, W-18, WC-5, WC-6, WC-8, and WC-11 through WC-14. Samples of the waste tank liquids and sludges were analyzed to determine (1) the major chemical constituents, (2) the principal radionuclides, (3) metals listed on the US Environmental Protection Agency (EPA) Contract Laboratory Program Inorganic Target Analyte List, (4) organic compounds, and (5) some physical properties. The organic chemical characterization consisted of determinations of the EPA Contract Laboratory Program Target Compound List volatile and semivolatile compounds, pesticides, and polychlorinated biphenyis (PCBs). This report provides data (1) to meet requirements under the Federal Facility Agreement (FFA) for the Oak Ridge Reservation to characterize the contents of LLLW tanks which have been removed from service and (2) to support planning for the treatment and disposal of the wastes

Heterotypic Protection and Induction of a Broad Heterotypic Neutralization Response by Rotavirus-Like Particles

Science.gov (United States)

Crawford, Sue E.; Estes, Mary K.; Ciarlet, Max; Barone, Christopher; O’Neal, Christine M.; Cohen, Jean; Conner, Margaret E.

1999-01-01

The recognition that rotaviruses are the major cause of life-threatening diarrheal disease and significant morbidity in young children has focused efforts on disease prevention and control of these viruses. Although the correlates of protection in children remain unclear, some studies indicate that serotype-specific antibody is important. Based on this premise, current live attenuated reassortant rotavirus vaccines include the four predominant serotypes of virus. We are evaluating subunit rotavirus vaccines, 2/6/7-VLPs and 2/4/6/7-VLPs, that contain only a single VP7 of serotype G1 or G3. In mice immunized parenterally twice, G3 virus-like particles (VLPs) induced a homotypic, whereas G1 VLPs induced a homotypic and heterotypic (G3) serum neutralizing immune response. Administration of three doses of G1 or G3 VLPs induced serum antibodies that neutralized five of seven different serotype test viruses. The inclusion of VP4 in the VLPs was not essential for the induction of heterotypic neutralizing antibody in mice. To confirm these results in another species, rabbits were immunized parenterally with two doses of 2/4/6/7-VLPs containing a G3 or G1 VP7, sequentially with G3 VLPs followed by G1 (G3/G1) VLPs, or with live or psoralen-inactivated SA11. High-titer homotypic serum neutralizing antibody was induced in all rabbits, and low-level heterotypic neutralizing antibody was induced in a subset of rabbits. The rabbits immunized with the G1 or G3/G1 VLPs in QS-21 were challenged orally with live G3 ALA rotavirus. Protection levels were similar in rabbits immunized with homotypic G3 2/4/6/7-VLPs, heterotypic G1 2/4/6/7-VLPs, or G3/G1 2/4/6/7-VLPs. Therefore, G1 2/4/6/7-VLPs can induce protective immunity against a live heterotypic rotavirus challenge in an adjuvant with potential use in humans. Following challenge, broad serum heterotypic neutralizing antibody responses were detected in rabbits parenterally immunized with G1, G3/G1, or G3 VLPs but not with SA11

Rotavirus vaccines

Science.gov (United States)

Yen, Catherine; Tate, Jacqueline E; Hyde, Terri B; Cortese, Margaret M; Lopman, Benjamin A; Jiang, Baoming; Glass, Roger I; Parashar, Umesh D

2014-01-01

Rotavirus is the leading cause of severe diarrhea among children rotavirus vaccines have been efficacious and effective, with many countries reporting substantial declines in diarrheal and rotavirus-specific morbidity and mortality. However, the full public health impact of these vaccines has not been realized. Most countries, including those with the highest disease burden, have not yet introduced rotavirus vaccines into their national immunization programs. Research activities that may help inform vaccine introduction decisions include (1) establishing effectiveness, impact, and safety for rotavirus vaccines in low-income settings; (2) identifying potential strategies to improve performance of oral rotavirus vaccines in developing countries, such as zinc supplementation; and (3) pursuing alternate approaches to oral vaccines, such as parenteral immunization. Policy- and program-level barriers, such as financial implications of new vaccine introductions, should be addressed to ensure that countries are able to make informed decisions regarding rotavirus vaccine introduction. PMID:24755452

Rotavirus vaccine and health-care utilization for rotavirus gastroenteritis in Tsu City, Japan

Science.gov (United States)

Kamiya, Hajime; Suga, Shigeru; Nagao, Mizuho; Ichimi, Ryoji; Fujisawa, Takao; Umemoto, Masakazu; Tanaka, Takaaki; Ito, Hiroaki; Tanaka, Shigeki; Ido, Masaru; Taniguchi, Koki; Ihara, Toshiaki; Nakano, Takashi

2016-01-01

Background Rotavirus vaccines were introduced in Japan in November 2011. We evaluated the subsequent reduction of the health-care burden of rotavirus gastroenteritis. Methods We conducted active surveillance for rotavirus gastroenteritis among children under 5 years old before and after the vaccine introduction. We surveyed hospitalization rates for rotavirus gastroenteritis in children in Tsu City, Mie Prefecture, Japan, from 2007 to 2015 and surveyed the number of outpatient visits at a Tsu City clinic from 2010 to 2015. Stool samples were obtained for rotavirus testing and genotype investigation. We assessed rotavirus vaccine coverage for infants living in Tsu City. Results In the pre-vaccine years (2007–2011), hospitalization rates for rotavirus gastroenteritis in children under 5 years old were 5.5, 4.3, 3.1 and 3.9 cases per 1000 person-years, respectively. In the post-vaccine years (2011–2015), the rates were 3.0, 3.5, 0.8 and 0.6 cases per 1000 person-years, respectively. The hospitalization rate decreased significantly in the 2013–2014 and 2014–2015 seasons compared to the average of the seasons before vaccine introduction (P rotavirus infection was 66. In the post-vaccine years (2011–2015), the numbers for each season was 23, 23, 7 and 5, respectively. The most dominant rotavirus genotype shifted from G3P[8] to G1P[8] and to G2P[4]. The coverage of one dose of rotavirus vaccine in Tsu City was 56.5% in 2014. Conclusion After the vaccine introduction, the hospitalization rates and outpatient visits for rotavirus gastroenteritis greatly decreased. PMID:28246579

Burden of Norovirus and Rotavirus in Children after Rotavirus Vaccine Introduction, Cochabamba, Bolivia

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McAtee, Casey L.; Webman, Rachel; Gilman, Robert H.; Mejia, Carolina; Bern, Caryn; Apaza, Sonia; Espetia, Susan; Pajuelo, Mónica; Saito, Mayuko; Challappa, Roxanna; Soria, Richard; Ribera, Jose P.; Lozano, Daniel; Torrico, Faustino

2016-01-01

The effectiveness of rotavirus vaccine in the field may set the stage for a changing landscape of diarrheal illness affecting children worldwide. Norovirus and rotavirus are the two major viral enteropathogens of childhood. This study describes the prevalence of norovirus and rotavirus 2 years after widespread rotavirus vaccination in Cochabamba, Bolivia. Stool samples from hospitalized children with acute gastroenteritis (AGE) and outpatients aged 5–24 months without AGE were recruited from an urban hospital serving Bolivia's third largest city. Both viruses were genotyped, and norovirus GII.4 was further sequenced. Norovirus was found much more frequently than rotavirus. Norovirus was detected in 69/201 (34.3%) of specimens from children with AGE and 13/71 (18.3%) of those without diarrhea. Rotavirus was detected in 38/201 (18.9%) of diarrheal specimens and 3/71 (4.2%) of non-diarrheal specimens. Norovirus GII was identified in 97.8% of norovirus-positive samples; GII.4 was the most common genotype (71.4% of typed specimens). Rotavirus G3P[8] was the most prevalent rotavirus genotype (44.0% of typed specimens) and G2P[4] was second most prevalent (16.0% of typed specimens). This community is likely part of a trend toward norovirus predominance over rotavirus in children after widespread vaccination against rotavirus. PMID:26598569

Burden of Norovirus and Rotavirus in Children After Rotavirus Vaccine Introduction, Cochabamba, Bolivia.

Science.gov (United States)

McAtee, Casey L; Webman, Rachel; Gilman, Robert H; Mejia, Carolina; Bern, Caryn; Apaza, Sonia; Espetia, Susan; Pajuelo, Mónica; Saito, Mayuko; Challappa, Roxanna; Soria, Richard; Ribera, Jose P; Lozano, Daniel; Torrico, Faustino

2016-01-01

The effectiveness of rotavirus vaccine in the field may set the stage for a changing landscape of diarrheal illness affecting children worldwide. Norovirus and rotavirus are the two major viral enteropathogens of childhood. This study describes the prevalence of norovirus and rotavirus 2 years after widespread rotavirus vaccination in Cochabamba, Bolivia. Stool samples from hospitalized children with acute gastroenteritis (AGE) and outpatients aged 5-24 months without AGE were recruited from an urban hospital serving Bolivia's third largest city. Both viruses were genotyped, and norovirus GII.4 was further sequenced. Norovirus was found much more frequently than rotavirus. Norovirus was detected in 69/201 (34.3%) of specimens from children with AGE and 13/71 (18.3%) of those without diarrhea. Rotavirus was detected in 38/201 (18.9%) of diarrheal specimens and 3/71 (4.2%) of non-diarrheal specimens. Norovirus GII was identified in 97.8% of norovirus-positive samples; GII.4 was the most common genotype (71.4% of typed specimens). Rotavirus G3P[8] was the most prevalent rotavirus genotype (44.0% of typed specimens) and G2P[4] was second most prevalent (16.0% of typed specimens). This community is likely part of a trend toward norovirus predominance over rotavirus in children after widespread vaccination against rotavirus. © The American Society of Tropical Medicine and Hygiene.

One-step multiplex real-time RT-PCR assay for detecting and genotyping wild-type group A rotavirus strains and vaccine strains (Rotarix® and RotaTeq®) in stool samples

Science.gov (United States)

Mijatovic-Rustempasic, Slavica; Esona, Mathew D.; Tam, Ka Ian; Quaye, Osbourne; Bowen, Michael D.

2016-01-01

Background. Group A rotavirus (RVA) infection is the major cause of acute gastroenteritis (AGE) in young children worldwide. Introduction of two live-attenuated rotavirus vaccines, RotaTeq® and Rotarix®, has dramatically reduced RVA associated AGE and mortality in developed as well as in many developing countries. High-throughput methods are needed to genotype rotavirus wild-type strains and to identify vaccine strains in stool samples. Quantitative RT-PCR assays (qRT-PCR) offer several advantages including increased sensitivity, higher throughput, and faster turnaround time. Methods. In this study, a one-step multiplex qRT-PCR assay was developed to detect and genotype wild-type strains and vaccine (Rotarix® and RotaTeq®) rotavirus strains along with an internal processing control (Xeno or MS2 RNA). Real-time RT-PCR assays were designed for VP7 (G1, G2, G3, G4, G9, G12) and VP4 (P[4], P[6] and P[8]) genotypes. The multiplex qRT-PCR assay also included previously published NSP3 qRT-PCR for rotavirus detection and Rotarix® NSP2 and RotaTeq® VP6 qRT-PCRs for detection of Rotarix® and RotaTeq® vaccine strains respectively. The multiplex qRT-PCR assay was validated using 853 sequence confirmed stool samples and 24 lab cultured strains of different rotavirus genotypes. By using thermostable rTth polymerase enzyme, dsRNA denaturation, reverse transcription (RT) and amplification (PCR) steps were performed in single tube by uninterrupted thermocycling profile to reduce chances of sample cross contamination and for rapid generation of results. For quantification, standard curves were generated using dsRNA transcripts derived from RVA gene segments. Results. The VP7 qRT-PCRs exhibited 98.8–100% sensitivity, 99.7–100% specificity, 85–95% efficiency and a limit of detection of 4–60 copies per singleplex reaction. The VP7 qRT-PCRs exhibited 81–92% efficiency and limit of detection of 150–600 copies in multiplex reactions. The VP4 qRT-PCRs exhibited 98.8�

Whole genome detection of rotavirus mixed infections in human, porcine and bovine samples co-infected with various rotavirus strains collected from sub-Saharan Africa.

Science.gov (United States)

Nyaga, Martin M; Jere, Khuzwayo C; Esona, Mathew D; Seheri, Mapaseka L; Stucker, Karla M; Halpin, Rebecca A; Akopov, Asmik; Stockwell, Timothy B; Peenze, Ina; Diop, Amadou; Ndiaye, Kader; Boula, Angeline; Maphalala, Gugu; Berejena, Chipo; Mwenda, Jason M; Steele, A Duncan; Wentworth, David E; Mphahlele, M Jeffrey

2015-04-01

Group A rotaviruses (RVA) are among the main global causes of severe diarrhea in children under the age of 5years. Strain diversity, mixed infections and untypeable RVA strains are frequently reported in Africa. We analysed rotavirus-positive human stool samples (n=13) obtained from hospitalised children under the age of 5years who presented with acute gastroenteritis at sentinel hospital sites in six African countries, as well as bovine and porcine stool samples (n=1 each), to gain insights into rotavirus diversity and evolution. Polyacrylamide gel electrophoresis (PAGE) analysis and genotyping with G-(VP7) and P-specific (VP4) typing primers suggested that 13 of the 15 samples contained more than 11 segments and/or mixed G/P genotypes. Full-length amplicons for each segment were generated using RVA-specific primers and sequenced using the Ion Torrent and/or Illumina MiSeq next-generation sequencing platforms. Sequencing detected at least one segment in each sample for which duplicate sequences, often having distinct genotypes, existed. This supported and extended the PAGE and RT-PCR genotyping findings that suggested these samples were collected from individuals that had mixed rotavirus infections. The study reports the first porcine (MRC-DPRU1567) and bovine (MRC-DPRU3010) mixed infections. We also report a unique genome segment 9 (VP7), whose G9 genotype belongs to lineage VI and clusters with porcine reference strains. Previously, African G9 strains have all been in lineage III. Furthermore, additional RVA segments isolated from humans have a clear evolutionary relationship with porcine, bovine and ovine rotavirus sequences, indicating relatively recent interspecies transmission and reassortment. Thus, multiple RVA strains from sub-Saharan Africa are infecting mammalian hosts with unpredictable variations in their gene segment combinations. Whole-genome sequence analyses of mixed RVA strains underscore the considerable diversity of rotavirus sequences and

Live attenuated tetravalent (G1-G4) bovine-human reassortant rotavirus vaccine (BRV-TV): Randomized, controlled phase III study in Indian infants.

Science.gov (United States)

Saluja, Tarun; Palkar, Sonali; Misra, Puneet; Gupta, Madhu; Venugopal, Potula; Sood, Ashwani Kumar; Dhati, Ravi Mandyam; Shetty, Avinash; Dhaded, Sangappa Malappa; Agarkhedkar, Sharad; Choudhury, Amlan; Kumar, Ramesh; Balasubramanian, Sundaram; Babji, Sudhir; Adhikary, Lopa; Dupuy, Martin; Chadha, Sangeet Mohan; Desai, Forum; Kukian, Darshna; Patnaik, Badri Narayan; Dhingra, Mandeep Singh

2017-06-16

Rotavirus remains the leading cause of diarrhoea among children rotavirus vaccine (BRV-TV) over the licensed human-bovine pentavalent rotavirus vaccine RV5. Phase III single-blind study (parents blinded) in healthy infants randomized (1:1) to receive three doses of BRV-TV or RV5 at 6-8, 10-12, and 14-16weeks of age. All concomitantly received a licensed diphtheria, tetanus, pertussis, hepatitis B, Haemophilus influenzae type b conjugate vaccine (DTwP-HepB-Hib) and oral polio vaccine (OPV). Immunogenic non-inferiority was evaluated in terms of the inter-group difference in anti-rotavirus serum IgA seroresponse (primary endpoint), and seroprotection/seroresponse rates to DTwP-HepB-Hib and OPV vaccines. Seroresponse was defined as a ≥4-fold increase in titers from baseline to D28 post-dose 3. Non-inferiority was declared if the difference between groups (based on the lower limit of the 95% confidence interval [CI]) was above -10%. Each subject was evaluated for solicited adverse events 7days and unsolicited & serious adverse events 28days following each dose of vaccination. Of 1195 infants screened, 1182 were randomized (590 to BRV-TV; 592 to RV5). Non-inferiority for rotavirus serum IgA seroresponse was not established: BRV-TV, 47.1% (95%CI: 42.8; 51.5) versus RV5, 61.2% (95%CI: 56.8; 65.5); difference between groups, -14.08% (95%CI: -20.4; -7.98). Serum IgA geometric mean concentrations at D28 post-dose 3 were 28.4 and 50.1U/ml in BRV-TV and RV5 groups, respectively. For all DTwP-HepB-Hib and OPV antigens, seroprotection/seroresponse was elicited in both groups and the -10% non-inferiority criterion between groups was met. There were 16 serious adverse events, 10 in BRV-TV group and 6 in RV5 group; none were classified as vaccine related. Both groups had similar vaccine safety profiles. BRV-TV was immunogenic but did not meet immunogenic non-inferiority criteria to RV5 when administered concomitantly with routine pediatric antigens in infants. Copyright © 2017

Human group A rotavirus infections in children in Denmark; detection of reassortant G9 strains and zoonotic P 14 strains

DEFF Research Database (Denmark)

Midgley, S.; Bottiger, B.; Jensen, T. G.

2014-01-01

One of the leading causes of severe childhood gastroenteritis are group A rotaviruses, and they have been found to be associated with similar to 40% of the annual gastroenteritis-associated hospitalizations in young Danish children......One of the leading causes of severe childhood gastroenteritis are group A rotaviruses, and they have been found to be associated with similar to 40% of the annual gastroenteritis-associated hospitalizations in young Danish children...

Rotavirus infection

Science.gov (United States)

Crawford, Sue E.; Ramani, Sasirekha; Tate, Jacqueline E.; Parashar, Umesh D.; Svensson, Lennart; Hagbom, Marie; Franco, Manuel A.; Greenberg, Harry B.; O’Ryan, Miguel; Kang, Gagandeep; Desselberger, Ulrich; Estes, Mary K.

2017-01-01

Rotavirus infections are a leading cause of severe, dehydrating gastroenteritis in children rotavirus over a decade ago, rotavirus infections still result in >200,000 deaths annually, mostly in low-income countries. Rotavirus primarily infects enterocytes and induces diarrhoea through the destruction of absorptive enterocytes (leading to malabsorption), intestinal secretion stimulated by rotavirus non-structural protein 4 and activation of the enteric nervous system. In addition, rotavirus infections can lead to antigenaemia (which is associated with more severe manifestations of acute gastroenteritis) and viraemia, and rotavirus can replicate in systemic sites, although this is limited. Reinfections with rotavirus are common throughout life, although the disease severity is reduced with repeat infections. The immune correlates of protection against rotavirus reinfection and recovery from infection are poorly understood, although rotavirus-specific immunoglobulin A has a role in both aspects. The management of rotavirus infection focuses on the prevention and treatment of dehydration, although the use of antiviral and anti-emetic drugs can be indicated in some cases. PMID:29119972

Group A Rotaviruses in Chinese Bats: Genetic Composition, Serology, and Evidence for Bat-to-Human Transmission and Reassortment.

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He, Biao; Huang, Xiaohong; Zhang, Fuqiang; Tan, Weilong; Matthijnssens, Jelle; Qin, Shaomin; Xu, Lin; Zhao, Zihan; Yang, Ling'en; Wang, Quanxi; Hu, Tingsong; Bao, Xiaolei; Wu, Jianmin; Tu, Changchun

2017-06-15

Bats are natural reservoirs for many pathogenic viruses, and increasing evidence supports the notion that bats can also harbor group A rotaviruses (RVAs), important causative agents of diarrhea in children and young animals. Currently, 8 RVA strains possessing completely novel genotype constellations or genotypes possibly originating from other mammals have been identified from African and Chinese bats. However, all the data were mainly based on detection of RVA RNA, present only during acute infections, which does not permit assessment of the true exposure of a bat population to RVA. To systematically investigate the genetic diversity of RVAs, 547 bat anal swabs or gut samples along with 448 bat sera were collected from five South Chinese provinces. Specific reverse transcription-PCR (RT-PCR) screening found four RVA strains. Strain GLRL1 possessed a completely novel genotype constellation, whereas the other three possessed a constellation consistent with the MSLH14-like genotype, a newly characterized group of viruses widely prevalent in Chinese insectivorous bats. Among the latter, strain LZHP2 provided strong evidence of cross-species transmission of RVAs from bats to humans, whereas strains YSSK5 and BSTM70 were likely reassortants between typical MSLH14-like RVAs and human RVAs. RVA-specific antibodies were detected in 10.7% (48/448) of bat sera by an indirect immunofluorescence assay (IIFA). Bats in Guangxi and Yunnan had a higher RVA-specific antibody prevalence than those from Fujian and Zhejiang provinces. These observations provide evidence for cross-species transmission of MSLH14-like bat RVAs to humans, highlighting the impact of bats as reservoirs of RVAs on public health. IMPORTANCE Bat viruses, such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), Ebola, Hendra, and Nipah viruses, are important pathogens causing outbreaks of severe emerging infectious diseases. However, little is known about bat viruses capable

Rotavirus Vaccine

Science.gov (United States)

Why get vaccinated?Rotavirus is a virus that causes diarrhea, mostly in babies and young children. The diarrhea can be severe, and lead ... and fever are also common in babies with rotavirus.Before rotavirus vaccine, rotavirus disease was a common ...

Efficacy of a Monovalent Human-Bovine (116E) Rotavirus Vaccine in Indian Infants: A Randomised Double Blind Placebo Controlled Trial

Science.gov (United States)

Bhandari, Nita; Rongsen-Chandola, Temsunaro; Bavdekar, Ashish; John, Jacob; Antony, Kalpana; Taneja, Sunita; Goyal, Nidhi; Kawade, Anand; Kang, Gagandeep; Rathore, Sudeep Singh; Juvekar, Sanjay; Muliyil, Jayaprakash; Arya, Alok; Shaikh, Hanif; Abraham, Vinod; Vrati, Sudhanshu; Proschan, Michael; Kohberger, Robert; Thiry, Georges; Glass, Roger; Greenberg, Harry B; Curlin, George; Mohan, Krishna; Harshavardhan, GVJA; Prasad, Sai; Rao, TS; Boslego, John; Bhan, Maharaj Kishan

2015-01-01

Background Rotavirus is the most common cause of severe dehydrating gastroenteritis in developing countries. Safe, effective, and affordable rotavirus vaccines are needed for developing countries. Methods In a double-blind placebo controlled multicentre trial, 6799 infants aged 6 to 7 weeks were randomised to receive three doses of an oral human-bovine natural reassortant vaccine (116E) or placebo at ages 6, 10, and 14 weeks. Primary outcome was severe (≥11 on the Vesikari scale) rotavirus gastroenteritis. Efficacy outcomes and adverse events were ascertained through active surveillance. Findings At analyses, the median age was 17·2 months; over 96% subjects received all three doses of the vaccine/placebo and ~1% were lost to follow up. 4532 and 2267 subjects were randomly assigned to receive vaccine and placebo, respectively. The per protocol analyses included 4354 subjects in the vaccine and 2187 subjects in the placebo group. 71 events of severe rotavirus gastroenteritis were reported in 4752 person years among the vaccinees compared to 76 events in 2360 person years in the placebo recipients; vaccine efficacy against severe rotavirus gastroenteritis was 53·6% (95% CI 35·0–66·9; Protavirus gastroenteritis episode was 55 (95% CI 37–97). The incidence of severe rotavirus gastroenteritis/100 person years was 1·5 in vaccine and 3·2 in placebo group and an incidence rate ratio of 0·46 (95% CI 0·33–0·65). The absolute rate reduction for severe rotavirus gastroenteritis was 1·7 (95% CI 2·5–0·9). Efficacy against severe gastroenteritis of any aetiology was 18·6% (95% CI 1·9–32·3); it was 24·1% (95% CI 5·8–38·7) in the first year of life. The prevalence of immediate, solicited, and serious adverse events were similar in both groups. There were six cases of intussusception amongst 4532 vaccinees and two amongst 2267 placebo recipients (P=0·73). All intussusception cases occurred after the third dose. Among vaccine and placebo recipients

Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses

Directory of Open Access Journals (Sweden)

Lee Chang-Won

2007-11-01

Full Text Available 1. Abstract The triple reassortant H3N2 viruses were isolated for the first time from pigs in 1998 and are known to be endemic in swine and turkey populations in the United States. In 2004, we isolated two H3N2 triple reassortant viruses from two turkey breeder flocks in Ohio and Illinois. Infected hens showed no clinical signs, but experienced a complete cessation of egg production. In this study, we evaluated three triple reassortant H3N2 isolates of turkey origin and one isolate of swine origin for their transmission between swine and turkeys. Although all 4 viruses tested share high genetic similarity in all 8 genes, only the Ohio strain (A/turkey/Ohio/313053/04 was shown to transmit efficiently both ways between swine and turkeys. One isolate, A/turkey/North Carolina/03, was able to transmit from pigs to turkeys but not vice versa. Neither of the other two viruses transmitted either way. Sequence analysis of the HA1 gene of the Ohio strain showed one amino acid change (D to A at residue 190 of the receptor binding domain upon transmission from turkeys to pigs. The Ohio virus was then tested for intraspecies transmission in three different avian species. The virus was shown to replicate and transmit among turkeys, replicate but does not transmit among chickens, and did not replicate in ducks. Identifying viruses with varying inter- and intra-species transmission potential should be useful for further studies on the molecular basis of interspecies transmission.

Interspecies and intraspecies transmission of triple reassortant H3N2 influenza A viruses.

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Yassine, Hadi M; Al-Natour, Mohammad Q; Lee, Chang-Won; Saif, Yehya M

2007-11-28

The triple reassortant H3N2 viruses were isolated for the first time from pigs in 1998 and are known to be endemic in swine and turkey populations in the United States. In 2004, we isolated two H3N2 triple reassortant viruses from two turkey breeder flocks in Ohio and Illinois. Infected hens showed no clinical signs, but experienced a complete cessation of egg production. In this study, we evaluated three triple reassortant H3N2 isolates of turkey origin and one isolate of swine origin for their transmission between swine and turkeys. Although all 4 viruses tested share high genetic similarity in all 8 genes, only the Ohio strain (A/turkey/Ohio/313053/04) was shown to transmit efficiently both ways between swine and turkeys. One isolate, A/turkey/North Carolina/03, was able to transmit from pigs to turkeys but not vice versa. Neither of the other two viruses transmitted either way. Sequence analysis of the HA1 gene of the Ohio strain showed one amino acid change (D to A) at residue 190 of the receptor binding domain upon transmission from turkeys to pigs. The Ohio virus was then tested for intraspecies transmission in three different avian species. The virus was shown to replicate and transmit among turkeys, replicate but does not transmit among chickens, and did not replicate in ducks. Identifying viruses with varying inter- and intra-species transmission potential should be useful for further studies on the molecular basis of interspecies transmission.

Efficacy of a monovalent human-bovine (116E) rotavirus vaccine in Indian children in the second year of life.

Science.gov (United States)

Bhandari, Nita; Rongsen-Chandola, Temsunaro; Bavdekar, Ashish; John, Jacob; Antony, Kalpana; Taneja, Sunita; Goyal, Nidhi; Kawade, Anand; Kang, Gagandeep; Rathore, Sudeep Singh; Juvekar, Sanjay; Muliyil, Jayaprakash; Arya, Alok; Shaikh, Hanif; Abraham, Vinod; Vrati, Sudhanshu; Proschan, Michael; Kohberger, Robert; Thiry, Georges; Glass, Roger; Greenberg, Harry B; Curlin, George; Mohan, Krishna; Harshavardhan, G V J A; Prasad, Sai; Rao, T S; Boslego, John; Bhan, Maharaj Kishan

2014-08-11

Rotavirus gastroenteritis is one of the leading causes of diarrhea in Indian children less than 2 years of age. The 116E rotavirus strain was developed as part of the Indo-US Vaccine Action Program and has undergone efficacy trials. This paper reports the efficacy and additional safety data in children up to 2 years of age. In a double-blind placebo controlled multicenter trial, 6799 infants aged 6-7 weeks were randomized to receive three doses of an oral human-bovine natural reassortant vaccine (116E) or placebo at ages 6, 10, and 14 weeks. The primary outcome was severe (≥11 on the Vesikari scale) rotavirus gastroenteritis. Efficacy outcomes and adverse events were ascertained through active surveillance. We randomly assigned 4532 and 2267 subjects to receive vaccine and placebo, respectively, with over 96% subjects receiving all three doses of the vaccine or placebo. The per protocol analyses included 4354 subjects in the vaccine and 2187 subjects in the placebo group. The overall incidence of severe RVGE per 100 person years was 1.3 in the vaccine group and 2.9 in the placebo recipients. Vaccine efficacy against severe rotavirus gastroenteritis in children up to 2 years of age was 55.1% (95% CI 39.9 to 66.4; pvaccine efficacy in the second year of life of 48.9% (95% CI 17.4 to 68.4; p=0.0056) was only marginally less than in the first year of life [56.3% (95% CI 36.7 to 69.9; pvaccine dose and all were reported only after the third dose. The sustained efficacy of the 116E in the second year of life is reassuring. The trial is registered with Clinical Trial Registry-India (# CTRI/2010/091/000102) and Clinicaltrials.gov (# NCT01305109). Copyright © 2014. Published by Elsevier Ltd.

Impact of rotavirus vaccination on rotavirus and all-cause gastroenteritis in peri-urban Kenyan children.

Science.gov (United States)

Wandera, Ernest Apondi; Mohammad, Shah; Bundi, Martin; Komoto, Satoshi; Nyangao, James; Kathiiko, Cyrus; Odoyo, Erick; Miring'u, Gabriel; Taniguchi, Koki; Ichinose, Yoshio

2017-09-12

A monovalent rotavirus vaccine (RV1) was introduced into the National Immunization Program in Kenya in July 2014. We examined the impact of the vaccine on hospitalization for all-cause acute gastroenteritis (AGE) and rotavirus-specific AGE and strain distribution at a large referral hospital which serves a predominantly peri-urban population in Central Kenya. Data on rotavirus AGE and strain distribution were derived from ongoing hospital-based AGE surveillance. Hospital administrative data were used to compare trends in all-cause AGE. Pre-vaccine (July 2009-June 2014) and post-vaccine (July 2014-June 2016) periods were compared for changes in hospitalization for all-cause AGE and rotavirus AGE and strain distribution. Following the vaccine introduction, the proportion of children aged rotavirus declined by 30% (95% CI: 19-45%) in the first year and 64% (95% CI: 49-77%) in the second year. Reductions in rotavirus positivity were most pronounced among the vaccine-eligible group (rotavirus and all-cause AGE were reduced substantially. There was an increased detection of G2P[4], G3P[6] and G3P[8], which coincided temporally with the timing of the vaccine introduction. Thus, introducing the rotavirus vaccine into the routine immunization program in Kenya has resulted in a notable decline in rotavirus and all-cause AGE hospitalizations in Central Kenya. This provides early evidence for public health policy makers in Kenya to support the sustained use of the rotavirus vaccine in routine immunizations. Copyright © 2017 Elsevier Ltd. All rights reserved.

A novel type of VP4 carried by a porcine rotavirus strain

International Nuclear Information System (INIS)

Liprandi, Ferdinando; Gerder, Marlene; Bastidas, Zoleida; Lopez, Jose A.; Pujol, Flor H.; Ludert, Juan E.; Joelsson, Daniel B.; Ciarlet, Max

2003-01-01

The gene encoding the VP8* trypsin-cleavage product of the VP4 protein of porcine rotavirus strain A34 was sequenced, and the predicted amino acid (aa) sequence was compared to the homologous region of all known P genotypes. The aa sequence of the VP8* of strain A34 shared low identity, ranging from 39% (bovine strain B223, P8[11]) to 76% (human strain 69M, P4[10]), with the homologous sequences of representative strains of the remaining 21 P genotypes. Phylogenetic relationships showed that the VP8* of strain A34 shares a common evolutionary lineage with those of human 69M (P4[10]) and equine H-2 (P4[12]) strains. Hyperimmune sera raised to strain A34 and to a genetic reassortant strain containing the VP4 gene from strain A34, both with high homologous neutralization titer via VP4, failed to neutralize strains representative of 15 different P genotypes. These results indicate that strain A34 should be considered as prototype of a new P genotype and serotype (P14[23]) and provide further evidence for the vast genetic and antigenic diversity of group A rotaviruses

Rotavirus (For Parents)

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... Staying Safe Videos for Educators Search English Español Rotavirus KidsHealth / For Parents / Rotavirus What's in this article? ... the Doctor Print en español El rotavirus About Rotavirus Almost all kids have had a rotavirus infection ...

Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus.

Science.gov (United States)

Rith, Sareth; Chin, Savuth; Sar, Borann; Y, Phalla; Horm, Srey Viseth; Ly, Sovann; Buchy, Philippe; Dussart, Philippe; Horwood, Paul F

2015-12-01

Despite annual co-circulation of different subtypes of seasonal influenza, co-infections between different viruses are rarely detected. These co-infections can result in the emergence of reassortant progeny. We document the detection of an influenza co-infection, between influenza A/H3N2 with A/H1N1pdm09 viruses, which occurred in a 3 year old male in Cambodia during April 2014. Both viruses were detected in the patient at relatively high viral loads (as determined by real-time RT-PCR CT values), which is unusual for influenza co-infections. As reassortment can occur between co-infected influenza A strains we isolated plaque purified clonal viral populations from the clinical material of the patient infected with A/H3N2 and A/H1N1pdm09. Complete genome sequences were completed for 7 clonal viruses to determine if any reassorted viruses were generated during the influenza virus co-infection. Although most of the viral sequences were consistent with wild-type A/H3N2 or A/H1N1pdm09, one reassortant A/H3N2 virus was isolated which contained an A/H1N1pdm09 NS1 gene fragment. The reassortant virus was viable and able to infect cells, as judged by successful passage in MDCK cells, achieving a TCID50 of 10(4)/ml at passage number two. There is no evidence that the reassortant virus was transmitted further. The co-infection occurred during a period when co-circulation of A/H3N2 and A/H1N1pdm09 was detected in Cambodia. It is unclear how often influenza co-infections occur, but laboratories should consider influenza co-infections during routine surveillance activities. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Beta 3 and PDI proteins isolated from human platelets bind with ECwt rotavirus in vitro

International Nuclear Information System (INIS)

Mayorga, Diana; Rubio, Linda; Guerrero-Fonseca, Carlos A; Acosta-Losada, Orlando

2010-01-01

Commercial integrin Beta 3 is currently not available and commercial PDI is too expensive, which is making access difficult to these proteins needed for conducting experiments aimed at the establishment of possible interactions between integrin Beta 3 and PDI and wild type rotavirus strains. Objective. To explore a methodology allowing isolation of proteins Beta 3 and PDI from human platelets to be used as antigens in the generation of rabbit polyclonal antibodies useful in the assessment of interactions between these proteins and rotavirus ECwt. Materials and methods. Proteins Beta 3 and PDI from human platelet lysates were separated using preparative electrophoresis under reducing conditions and then eluted. Interactions of these proteins with rotavirus ECwt were analyzed using co-immunoprecipitation, Western blotting and capture ELISA. Results. Proteins from human platelet lysates were separated by preparative electrophoresis under reducing conditions. The identification of proteins Beta 3 and PDI present in a gel slice was performed through their reaction with commercial antibodies in a Western blotting analysis. Protein purity was established after electro elution from a gel slice. Polyclonal antibodies against protein Beta 3 were generated in rabbit. Incubation of eluted proteins Beta 3 and PDI with rotavirus ECwt showed in co-immunoprecipitation and ELISA assays that these proteins bound virus in vitro. The same binding was showed to occur when rotavirus was incubated with isolated small intestinal villi from suckling mice. Conclusions. Relatively high amounts of proteins Beta 3 and PDI were partially purified from human platelets by preparative electrophoresis. The isolation of these proteins allowed the generation of polyclonal antibodies against Beta 3 in addition to the establishment of the in vitro interaction of proteins Beta 3 and PDI with rotavirus ECwt. This interaction was also demonstrated in vivo after incubating the virus with isolated small

Impact and Effectiveness of Monovalent Rotavirus Vaccine Against Severe Rotavirus Diarrhea in Ghana.

Science.gov (United States)

Armah, George; Pringle, Kimberly; Enweronu-Laryea, Christabel C; Ansong, Daniel; Mwenda, Jason M; Diamenu, Stanley K; Narh, Clement; Lartey, Belinda; Binka, Fred; Grytdal, Scott; Patel, Manish; Parashar, Umesh; Lopman, Ben

2016-05-01

Ghana was among the first African nations to introduce monovalent rotavirus vaccine (RV1) into its childhood immunization schedule in April 2012. We aimed to assess the impact of vaccine introduction on rotavirus and acute gastroenteritis (AGE) hospitalizations and to estimate vaccine effectiveness (VE). Using data from 2 teaching hospitals, monthly AGE and rotavirus admissions by age were examined 40 months before and 31 months after RV1 introduction using interrupted time-series analyses. From January 2013, we enrolled children vaccination by rotavirus case-patient status, controlling for potential confounders. Vaccine coverage ranged from 95% to 100% for dose 1 and 93% to 100% for dose 2. In the first 3 years after vaccine introduction, the percentage of hospital admissions positive for rotavirus fell from 48% in the prevaccine period to 28% (49% adjusted rate reduction; 95% confidence interval [CI], 32%-63%) postvaccination among vaccine coverage, it was not possible to arrive at robust VE estimates; any-dose VE against rotavirus hospitalization was estimated at 60% (95% CI, -2% to 84%;P= .056). Results from the first 3 years following RV1 introduction suggest substantial reductions of pediatric diarrheal disease as a result of vaccination. Our VE estimate is consistent with the observed rotavirus decrease and with efficacy estimates from elsewhere in sub-Saharan Africa. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Rotavirus A strains obtained from children with acute gastroenteritis in Mozambique, 2012-2013: G and P genotypes and phylogenetic analysis of VP7 and partial VP4 genes.

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João, Eva Dora; Strydom, Amy; O'Neill, Hester G; Cuamba, Assa; Cassocera, Marta; Acácio, Sozinho; Mandomando, Inácio; Motanyane, Lithabiso; Page, Nicola; de Deus, Nilsa

2018-01-01

In Mozambique rotavirus (RV) was shown to be the greatest cause of acute diarrhoea in infants from 0 to 11 months, and in 2015, national rotavirus vaccination was introduced. As with other developing countries, there is very limited active strain characterisation. Rotavirus positive clinical specimens, collected between 2012 and 2013, have now provided information on the genotypes circulating in southern Mozambique prior to vaccine introduction. Genotypes G2 (32.4%), G12 (28.0%), P[4] (41.4%) and P[6] (22.9%) (n = 157) strains were commonly detected with G2P[4] (42.3%) RVs being predominant, specifically during 2013. Phylogenetic evaluation of the VP7 and VP8* encoding genes showed, for the majority of the Mozambican strains, that they clustered with other African strains based on genotype. RVA/Human-wt/MOZ/0153/2013/G2P[4], RVA/Human-wt/MOZ/0308/2012/G2P[4] and RVA/Human-wt/MOZ/0288/2012/G12P[8] formed separate clusters from the other Mozambican strains with similar genotypes, suggesting possible reassortment. Amino acid substitutions in selected epitope regions also supported phylogenetic clustering. As expected, the VP7 and VP8* genes from the Mozambican strains differed from both the RotaTeq ® (SC2-9) G2P[5] and Rotarix ® (A41CB052A) G1P[8] genes. This study provides information on the genetic diversity of rotavirus strains prior to vaccine introduction and generates baseline data for future monitoring of any changes in rotavirus strains in response to vaccine pressure.

Prevalence of rotavirus genotypes in children younger than 5 years of age before the introduction of a universal rotavirus vaccination program: report of rotavirus surveillance in Turkey.

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Riza Durmaz

Full Text Available BACKGROUND: Group A rotaviruses are the most common causative agent of acute gastroenteritis among children less than 5 years of age throughout the world. This sentinel surveillance study was aimed to obtain baseline data on the rotavirus G and P genotypes across Turkey before the introduction of a universal rotavirus vaccination program. METHODS: Rotavirus antigen-positive samples were collected from 2102 children less than 5 years of age who attended hospitals participating in the Turkish Rotavirus Surveillance Network. Rotavirus antigen was detected in the laboratories of participating hospitals by commercial serological tests such as latex agglutination, immunochromatographic test or enzyme immunoassay. Rotavirus G and P genotypes were determined by reverse transcription polymerase chain reaction (RT-PCR using consensus primers detecting the VP7 and VP4 genes, followed by semi-nested type-specific multiplex PCR. RESULTS: RT-PCR found rotavirus RNA in 1644 (78.2% of the samples tested. The highest rate of rotavirus positivity (38.7% was observed among children in the 13 to 24 month age group, followed by children in the age group of 25 to 36 months (28.3%. A total of eight different G types, six different P types, and 42 different G-P combinations were obtained. Four common G types (G1, G2, G3, and G9 and two common P types (P[8] and P[4] accounted for 95.1% and 98.8% of the strains, respectively. G9P[8] was the most common G/P combination found in 40.5% of the strains followed by G1P[8] (21.6%, G2P[8] (9.3%, G2P[4] (6.5%, G3P[8] (3.5%, and finally, G4P[8] (3.4%. These six common genotypes included 83.7% of the strains tested in this study. The rate of uncommon genotypes was 14%. CONCLUSION: The majority of the strains analyzed belonged to the G1-G4 and G9 genotypes, suggesting high coverage of current rotavirus vaccines. This study also demonstrates a dramatic increase in G9 genotype across the country.

Prevalence of Rotavirus Genotypes in Children Younger than 5 Years of Age before the Introduction of a Universal Rotavirus Vaccination Program: Report of Rotavirus Surveillance in Turkey

Science.gov (United States)

Durmaz, Riza; Kalaycioglu, Atila Taner; Acar, Sumeyra; Bakkaloglu, Zekiye; Karagoz, Alper; Korukluoglu, Gulay; Ertek, Mustafa; Torunoglu, Mehmet Ali

2014-01-01

Background Group A rotaviruses are the most common causative agent of acute gastroenteritis among children less than 5 years of age throughout the world. This sentinel surveillance study was aimed to obtain baseline data on the rotavirus G and P genotypes across Turkey before the introduction of a universal rotavirus vaccination program. Methods Rotavirus antigen-positive samples were collected from 2102 children less than 5 years of age who attended hospitals participating in the Turkish Rotavirus Surveillance Network. Rotavirus antigen was detected in the laboratories of participating hospitals by commercial serological tests such as latex agglutination, immunochromatographic test or enzyme immunoassay. Rotavirus G and P genotypes were determined by reverse transcription polymerase chain reaction (RT-PCR) using consensus primers detecting the VP7 and VP4 genes, followed by semi-nested type-specific multiplex PCR. Results RT-PCR found rotavirus RNA in 1644 (78.2%) of the samples tested. The highest rate of rotavirus positivity (38.7%) was observed among children in the 13 to 24 month age group, followed by children in the age group of 25 to 36 months (28.3%). A total of eight different G types, six different P types, and 42 different G–P combinations were obtained. Four common G types (G1, G2, G3, and G9) and two common P types (P[8] and P[4]) accounted for 95.1% and 98.8% of the strains, respectively. G9P[8] was the most common G/P combination found in 40.5% of the strains followed by G1P[8] (21.6%), G2P[8] (9.3%), G2P[4] (6.5%), G3P[8] (3.5%), and finally, G4P[8] (3.4%). These six common genotypes included 83.7% of the strains tested in this study. The rate of uncommon genotypes was 14%. Conclusion The majority of the strains analyzed belonged to the G1–G4 and G9 genotypes, suggesting high coverage of current rotavirus vaccines. This study also demonstrates a dramatic increase in G9 genotype across the country. PMID:25437502

Rotavirus Symptoms

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... Search Form Controls Cancel Submit Search The CDC Rotavirus Note: Javascript is disabled or is not supported ... message, please visit this page: About CDC.gov . Rotavirus Home About Rotavirus Symptoms Transmission Treatment Photos Vaccination ...

Rotavirus Treatment

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Genetic Reassortment Among the Influenza Viruses (Avian Influenza, Human Influenza and Swine Influenza in Pigs

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Dyah Ayu Hewajuli

2012-12-01

Full Text Available Influenza A virus is a hazardous virus and harm to respiratory tract. The virus infect birds, pigs, horses, dogs, mammals and humans. Pigs are important hosts in ecology of the influenza virus because they have two receptors, namely NeuAc 2,3Gal and NeuAc 2,6Gal which make the pigs are sensitive to infection of influenza virus from birds and humans and genetic reassortment can be occurred. Classical swine influenza H1N1 viruses had been circulated in pigs in North America and other countries for 80 years. In 1998, triple reassortant H3N2 swine influenza viruses that contains genes of human influenza A virus (H3N2, swine influenza virus (H1N1 and avian influenza are reported as cause an outbreaks in pigs in North America. Furthermore, the circulation of triple reassortant H3N2 swine influenza virus resulting reassortant H1N1 swine influenza and reassortant H1N2 swine influenza viruses cause infection in humans. Humans who were infected by triple reassortant swine influenza A virus (H1N1 usually made direct contact with pigs. Although without any clinical symptoms, pigs that are infected by triple reassortant swine influenza A (H1N1 can transmit infection to the humans around them. In June 2009, WHO declared that pandemic influenza of reassortant H1N1 influenza A virus (novel H1N1 has reached phase 6. In Indonesia until 2009, there were 1005 people were infected by H1N1 influenza A and 5 of them died. Novel H1N1 and H5N1 viruses have been circulated in humans and pigs in Indonesia. H5N1 reassortant and H1N1 viruses or the seasonal flu may could arise because of genetic reassortment between avian influenza and humans influenza viruses that infect pigs together.

Whole genome characterisation of a porcine-like human reassortant G26P[19] Rotavirus A strain detected in a child hospitalised for diarrhoea in Nepal, 2007.

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Agbemabiese, Chantal Ama; Nakagomi, Toyoko; Gauchan, Punita; Sherchand, Jeevan Bahadur; Pandey, Basu Dev; Cunliffe, Nigel A; Nakagomi, Osamu

2017-10-01

A rare G26 Rotavirus A strain RVA/Human-wt/NPL/07N1760/2007/G26P[19] was detected in a child hospitalised for acute diarrhoea in Kathmandu, Nepal. The complete genome of 07N1760 was determined in order to explore its evolutionary history as well as examine its relationship to a Vietnamese strain RVA/Human-wt/VNM/30378/2009/G26P[19], the only G26 strain whose complete genotype constellation is known. The genotype constellation of 07N1760 was G26-P[19]-I12-R1-C1-M1-A8-N1-T1-E1-H1, a unique constellation identical to that of the Vietnamese 30378 except the VP6 gene. Phylogenetic analysis revealed that both strains were unrelated at the lineage level despite their similar genotype constellation. The I12 VP6 gene of 07N1760 was highly divergent from the six currently deposited I12 sequences in the GenBank. Except for its NSP2 gene, the remaining genes of 07N1760 shared lineages with porcine and porcine-like human RVA genes. The NSP2 gene belonged to a human RVA N1 lineage which was distinct from typical porcine and porcine-like human lineages. In conclusion, the Nepali G26P[19] strain 07N1760 was a porcine RVA strain which derived an NSP2 gene from a human Wa-like RVA strain by intra-genotype reassortment probably after transmission to the human host. Copyright © 2017 Elsevier B.V. All rights reserved.

Novel reassortant swine influenza viruses are circulating in Danish pigs

DEFF Research Database (Denmark)

Breum, Solvej Østergaard; Hjulsager, Charlotte Kristiane; Trebbien, Ramona

of the reassortant viruses comprised a HA gene similar to H1 of H1N1 avian-like swine influenza virus (SIV) and a NA gene most closely related to N2 gene of human H3N2 influenza virus that circulated in humans in the mid 1990s. The internal genes of this reassortant virus with the subtype H1avN2hu all belonged...... to the H1N1 avian-like SIV lineages. Until now this novel virus H1avN2hu has only been detected in Danish swine. The other novel reassortant virus contained the HA gene from H1N1pdm09 virus and a NA gene similar to the N2 gene of H3N2 SIV that have been circulating in European swine since the mid 1980s...

Analysis by rotavirus gene 6 reverse transcriptase-polymerase chain reaction assay of rotavirus-positive gastroenteritis cases observed during the vaccination phase of the Rotavirus Efficacy and Safety Trial (REST)

Science.gov (United States)

Matson, David O; Vesikari, Timo; Dennehy, Penelope; Dallas, Michael D; Goveia, Michelle G; Itzler, Robbin F; Ciarlet, Max

2014-01-01

During the vaccination phase of the Rotavirus Efficacy and Safety Trial (REST), the period between the administration of dose 1 through 13 days after the administration of dose 3, there were more wild-type rotavirus gastroenteritis (RVGE) cases among vaccine recipients compared with placebo recipients using the protocol-specified microbiological plaque assay in the clinical-efficacy cohort, a subset of subjects where vaccine efficacy against RVGE of any severity was assessed. In this study, a rotavirus genome segment 6-based reverse transcriptase–polymerase chain reaction assay was applied post hoc to clarify the accuracy of type categorization of all these RVGE cases in vaccine recipients during the vaccination phase of REST. The assay characterized 147 (90%) of 163 re-assayed RVGE cases or rotavirus-associated health care contacts as type-determinable: either wild-type or vaccine-type rotavirus strains. In the clinical-efficacy cohort (N = 5673), 19 (18.8%) of 101 samples from RVGE cases contained wild-type rotavirus, 70 (69.3%) vaccine virus, and 12 (11.9%) were indeterminable. In the large-scale cohort (N = 68,038), 10 (34.5%) of 29 samples from RVGE-related health care contacts contained wild-type rotavirus strains, 15 (51.7%) vaccine-type rotavirus strains, and 4 (13.8%) were indeterminable. Of the 33 samples from RVGE cases in placebo recipients, all were confirmed to contain wild-type rotaviruses. Altogether, this post-hoc re-evaluation showed that the majority (75%) of type-determinable RVGE cases or health care contacts that occurred during the vaccination phase of REST in vaccine recipients were associated with vaccine-type rotavirus strains rather than wild-type rotavirus strains. PMID:25424931

Analysis by rotavirus gene 6 reverse transcriptase-polymerase chain reaction assay of rotavirus-positive gastroenteritis cases observed during the vaccination phase of the Rotavirus Efficacy and Safety Trial (REST).

Science.gov (United States)

Matson, David O; Vesikari, Timo; Dennehy, Penelope; Dallas, Michael D; Goveia, Michelle G; Itzler, Robbin F; Ciarlet, Max

2014-01-01

During the vaccination phase of the Rotavirus Efficacy and Safety Trial (REST), the period between the administration of dose 1 through 13 days after the administration of dose 3, there were more wild-type rotavirus gastroenteritis (RVGE) cases among vaccine recipients compared with placebo recipients using the protocol-specified microbiological plaque assay in the clinical-efficacy cohort, a subset of subjects where vaccine efficacy against RVGE of any severity was assessed. In this study, a rotavirus genome segment 6-based reverse transcriptase-polymerase chain reaction assay was applied post hoc to clarify the accuracy of type categorization of all these RVGE cases in vaccine recipients during the vaccination phase of REST. The assay characterized 147 (90%) of 163 re-assayed RVGE cases or rotavirus-associated health care contacts as type-determinable: either wild-type or vaccine-type rotavirus strains. In the clinical-efficacy cohort (N = 5673), 19 (18.8%) of 101 samples from RVGE cases contained wild-type rotavirus, 70 (69.3%) vaccine virus, and 12 (11.9%) were indeterminable. In the large-scale cohort (N = 68,038), 10 (34.5%) of 29 samples from RVGE-related health care contacts contained wild-type rotavirus strains, 15 (51.7%) vaccine-type rotavirus strains, and 4 (13.8%) were indeterminable. Of the 33 samples from RVGE cases in placebo recipients, all were confirmed to contain wild-type rotaviruses. Altogether, this post-hoc re-evaluation showed that the majority (75%) of type-determinable RVGE cases or health care contacts that occurred during the vaccination phase of REST in vaccine recipients were associated with vaccine-type rotavirus strains rather than wild-type rotavirus strains.

Rotavirus infection in Saudi Arabia

International Nuclear Information System (INIS)

Kheyami, Ali M.; Cunliffe, Nigel A.; Hart, C. Anthony

2006-01-01

Human rotavirus, an important causative agent of severe gastroenteritis in infants and young children worldwide, leads to high morbidity in both developing and developed countries. Effective control depends upon an accurate understanding of disease burden and the relative importance of circulating serotypes. We examined the epidemiology and disease burden of rotavirus in Saudi Arabia through a review of 22 published studies of rotavirus and the antilogy diarrhea carried out from 1982 to 2003. The prevalence of rotavirus ranged between 10% to 46% with a median of 30%. Most cases were among children less than 2 years of age, and particularly in first year of life. There were significant differences in the seasonability within Saudi Arabia with increased infection during winter in some cities and during summer in others. G1 was the predominant serotype followed by G4, G3 and G2, in 4 studies where strains have been G-typed. The prevalence of noticeable strains ranged from 11.0% to 31.3%. No data were available on P types... Results of electropherotyping in 4 studies revealed that the long elctropherotype was predominant. Rotavirus is an important cause of severe diarrhea in Saudi children. However, the available data on rotavirus strains in circulation are limited. And there is an urgent need for up-to-date and comprehensive studies to evaluate rotavirus strains in circulation and identify unusual types that could be incorporated into future vaccines. (author)

Efficacy, immunogenicity, and safety of two doses of a tetravalent rotavirus vaccine RRV-TV in Ghana with the first dose administered during the neonatal period.

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Armah, George E; Kapikian, Albert Z; Vesikari, Timo; Cunliffe, Nigel; Jacobson, Robert M; Burlington, D Bruce; Ruiz, Leonard P

2013-08-01

Oral rhesus/rhesus-human reassortant rotavirus tetravalent vaccine (RRV-TV) was licensed in 1998 but withdrawn in 1999 due to a rare association with intussusception, which occurred disproportionately in infants receiving their first dose at ≥90 days of age. This study examined RRV-TV for the prevention of rotavirus gastroenteritis (RV-GE) in Ghana, West Africa, with infants receiving the first dose during the neonatal period and the second before 60 days of age. In a double-blinded, randomized, placebo-controlled trial in Navrongo, Ghana, we recruited neonates to receive 2 doses of RRV-TV or placebo and followed them to age 12 months. In the intention-to-treat population of 998 infants, we measured a vaccine efficacy of 63.1% against RV-GE of any severity associated with any of the 4 serotypes represented in the vaccine and 60.7% against RV-GE associated with any rotavirus serotype. RRV-TV in a 2-dose schedule with the first dose during the neonatal period is efficacious in preventing RV-GE in rural Ghana. Neonatal dosing results in early protection and may be the optimum schedule to avoid or significantly reduce intussusception, now reported to be associated in international settings with the 2 most widely marketed, licensed, live virus, oral rotavirus vaccines.

Study on single step solid state synthesis of WC@C nanocomposite and electrochemical stability of synthesized WC@C & Pt/WC@C for alcohol oxidation (methanol/ethanol)

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Singla, Gourav, E-mail: gsinghla@gmail.com; Singh, K., E-mail: kusingh@thapar.edu; Pandey, O.P., E-mail: oppandey@thapar.edu

2016-04-25

WC@C nano composite was prepared by a single step solid–state reaction through in situ reduction and carburization of WO{sub 3} in the presence of Mg and activated charcoal. The XRD results and thermodynamics analysis showed that the optimization of reaction temperature facilitates the reduction as well as carburization of tungsten oxide(s) at different reaction temperature. Thermogravimetric analysis of the product was done to assess the thermal stability in air. The Raman spectroscopy was used to find out the nature (amorphous/graphitic) of carbon in the obtained phase. The N{sub 2} adsorption–desorption measurement showed a narrow pore size distribution from 3 to 4 nm with BET surface area of up to 522.5 m{sup 2}/g. TEM/HRTEM images confirmed formation of the WC nano particles with spherical morphology. Electrochemical stability of pure and platinized carbide sample (Pt/WC) has been investigated using cyclic voltammetry in acidic media for alcohol (methanol and ethanol) oxidation. - Highlights: • Tungsten carbide nano powder was synthesized using charcoal as carbon source. • Formation of WC occurs through the formation of lower tungsten oxide. • CO{sub 2}/CO ratio effect the formation of WC. • Mesoporous tungsten carbide with surface areas 522.5 m{sup 2}/g obtained by using charcoal. • Pt modified WC powder showed higher electrochemical stability.

On the sintering behaviour of steel bonded TiC-Cr3C2 and TiC-Cr3C2-WC mixed carbides

International Nuclear Information System (INIS)

Stojanov, L.G.; Exner, H.E.

1978-01-01

Powder mixtures of TiC+Cr 3 C 2 and TiC+Cr 3 C 2 + WC were hot pressed to nearly full density. The lattice parameter of the resulting cubic mixed crystal decreases linearly with increasing additions of Cr 3 C 2 and (Cr 3 C 2 +WC 1:1). Microhardness increases with Cr 3 C 2 content up to 20 wt.%. By addition of WC, microhardness is increased further and reaches a maximum value of approx. 38 000 MN/m 2 for 20 wt.% Cr 3 C 2 and 20 wt.% WC. From these solid solutions powder compositions of Ferro-TiC type were produced by milling with 55 wt.% Fe and 0.4 wt.% C. The sintering behaviour of these powders was studied in a vacuum dilatometer. The pronounced increase of shrinkage by Cr 3 C 2 and higher amounts of Cr 3 C 2 +WC dissolved in TiC previous to binder phase melting is attributed to the increased solubility of the carbide in solid iron. Presintering at 700 0 C in hydrogen has a negative influence on sintering activity and requires much higher temperatures for complete densification during subsequent vacuum sintering. (orig.) [de

Cold compaction behavior and pressureless sinterability of ball milled WC and WC/Cu powders

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Hashemi Seyed R.

2016-01-01

Full Text Available In this research, cold compaction behavior and pressureless sinterability of WC, WC-10%wtCu and WC-30%wtCu powders were investigated. WC and WC/Cu powders were milled in a planetary ball mill for 20h. The milled powders were cold compacted at 100, 200, 300 and 400 MPa pressures. The compressibility behavior of the powders was evaluated using the Heckel, Panelli-Ambrosio and Ge models. The results showed that the Panelli-Ambrosio was the preferred equation for description the cold compaction behavior of the milled WC and WC-30%wtCu powders. Also, the most accurate model for describing the compressibility of WC-10%wtCu powders was the Heckel equation. The cold compacts were sintered at 1400°C. It was found that by increasing the cold compaction pressure of powder compacts before sintering, the sinterability of WC-30%wtCu powder compacts was enhanced. However, the cold compaction magnitude was not affected significantly on the sinterability of WC and WC-10%wtCu powders. The microstructural investigations of the sintered samples by Scanning Electron Microscopy (SEM confirmed the presence of porosities at the interface of copper-tungsten carbide phases.

Effects of WC phase contents on the microstructure, mechanical properties and tribological behaviors of WC/a-C superlattice coatings

Energy Technology Data Exchange (ETDEWEB)

Pu, Jibin [Key Laboratory of Marine Materials and Related Technologies, Key Laboratory of Marine Materials and Protective Technologies of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); He, Dongqing [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of Chinese Academy of Sciences, Beijing 100039 (China); Wang, Liping, E-mail: lpwang@licp.cas.cn [Key Laboratory of Marine Materials and Related Technologies, Key Laboratory of Marine Materials and Protective Technologies of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

2015-12-01

Graphical abstract: - Highlights: • WC/a-C superlattice coatings were synthesized with various WC phase content. • Superlattice structure diminished residual stress and densified microstructure. • Nanocomposite coating with W 5.43 at.% achieved the optimal tribological properties. • Friction triggered WO{sub 3} lead to a low friction coefficient at 200 °C. - Abstract: Nanocomposite WC/a-C coatings with variable contents of tungsten carbide (WC{sub 1−x}) and amorphous carbon (a-C) were successfully fabricated using a magnetron sputtering process. The microstructure, mechanical properties and tribological behaviors of the as-fabricated coatings were investigated and compared. The results showed that the “superlattice coating” feature of an alternating multilayer structure with a-C and WC{sub 1−x} nanocrystallites layers on the nanoscale was formed. These multilayer superlattice structures led to diminished residual stress and improved the strength of the adhesion to the substrate. The WC/a-C coating with W 5.43 at.% exhibited low friction coefficients of 0.05 at 25 °C and 0.28 at 200 °C. This significant improvement in the tribological performances of the WC/a-C coating was mainly attributed to the superior “superlattice” microstructure and the formation of a continuously compacted tribofilms, which was rich in graphitized carbon at 25 °C and dominated by the friction triggered WO{sub 3} at 200 °C. Moreover, the WC/a-C coating with W 5.43 at.% achieved optimal anti-wear properties at 25 °C due to the synergistic combination of the enhancement effects of the WC{sub 1−x} nanoparticles and the partition effect from the transfer film that restricted direct contact of the steel ball with the coating and thus prevented further intense wear. The accelerated wear of the WC/a-C coating with the increase of the WC phase content at 200 °C might be due to the combination of oxidation wear and abrasive wear that originated from the WC{sub 1−x} phase.

Value of post-licensure data on benefits and risks of vaccination to inform vaccine policy: The example of rotavirus vaccines.

Science.gov (United States)

Parashar, Umesh D; Cortese, Margaret M; Payne, Daniel C; Lopman, Benjamin; Yen, Catherine; Tate, Jacqueline E

2015-11-27

In 1999, the first rhesus-human reassortant rotavirus vaccine licensed in the United States was withdrawn within a year of its introduction after it was linked with intussusception at a rate of ∼1 excess case per 10,000 vaccinated infants. While clinical trials of 60,000-70,000 infants of each of the two current live oral rotavirus vaccines, RotaTeq (RV5) and Rotarix (RV1), did not find an association with intussusception, post-licensure studies have documented a risk in several high and middle income countries, at a rate of ∼1-6 excess cases per 100,000 vaccinated infants. However, considering this low risk against the large health benefits of vaccination that have been observed in many countries, including in countries with a documented vaccine-associated intussusception risk, policy makers and health organizations around the world continue to support the routine use of RV1 and RV5 in national infant immunization programs. Because the risk and benefit data from affluent settings may not be directly applicable to developing countries, further characterization of any associated intussusception risk following rotavirus vaccination as well as the health benefits of vaccination is desirable for low income settings. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Ltd.. All rights reserved.

The impact of rotavirus gastroenteritis on the family

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Kelly Claudia M

2009-02-01

Full Text Available Abstract Background Rotavirus is the leading cause of severe diarrhea in young children and causes substantial morbidity and mortality. Although the clinical aspects have been well described, little information is available regarding the emotional, social, and economic impact of rotavirus gastroenteritis on the family of a sick child. The objectives of this study were to: 1 assess the family impact of rotavirus gastroenteritis through qualitative interviews with parents; 2 compare the clinical severity of rotavirus-positive and negative gastroenteritis; 3 test a questionnaire asking parents to rank the importance of various factors associated with a case of rotavirus gastroenteritis. Methods The study enrolled parents and children (2–36 months of age brought to one of the study sites (outpatient clinic or ER if the child experienced ≥ 3 watery or looser-than normal stools and/or forceful vomiting within any 24-hour period within the prior 3 days. The clinical severity of each child's illness was rated using a clinical scoring system and stool samples were tested for rotavirus antigen. Parents of rotavirus-positive children were invited to participate in focus group or individual interviews and subsequently completed a questionnaire regarding the impact of their child's illness. Results Of 62 enrolled children, 43 stool samples were collected and 63% tested positive for rotavirus. Illness was more severe in children with rotavirus-positive compared to rotavirus-negative gastroenteritis (92% vs. 37.5% rated as moderate/severe. Seventeen parents of rotavirus-positive children participated in the interviews and completed the written questionnaire. Parents were frightened by the severity of vomiting and diarrhea associated with rotavirus gastroenteritis, and noted that family life was impacted in several ways including loss of sleep, missed work, and an inability to complete normal household tasks. They expressed frustration at the lack of a

Rapid detection and subtyping of human influenza A viruses and reassortants by pyrosequencing.

Directory of Open Access Journals (Sweden)

Yi-Mo Deng

Full Text Available BACKGROUND: Given the continuing co-circulation of the 2009 H1N1 pandemic influenza A viruses with seasonal H3N2 viruses, rapid and reliable detection of newly emerging influenza reassortant viruses is important to enhance our influenza surveillance. METHODOLOGY/PRINCIPAL FINDINGS: A novel pyrosequencing assay was developed for the rapid identification and subtyping of potential human influenza A virus reassortants based on all eight gene segments of the virus. Except for HA and NA genes, one universal set of primers was used to amplify and subtype each of the six internal genes. With this method, all eight gene segments of 57 laboratory isolates and 17 original specimens of seasonal H1N1, H3N2 and 2009 H1N1 pandemic viruses were correctly matched with their corresponding subtypes. In addition, this method was shown to be capable of detecting reassortant viruses by correctly identifying the source of all 8 gene segments from three vaccine production reassortant viruses and three H1N2 viruses. CONCLUSIONS/SIGNIFICANCE: In summary, this pyrosequencing assay is a sensitive and specific procedure for screening large numbers of viruses for reassortment events amongst the commonly circulating human influenza A viruses, which is more rapid and cheaper than using conventional sequencing approaches.

Rapid detection and subtyping of human influenza A viruses and reassortants by pyrosequencing.

Science.gov (United States)

Deng, Yi-Mo; Caldwell, Natalie; Barr, Ian G

2011-01-01

Given the continuing co-circulation of the 2009 H1N1 pandemic influenza A viruses with seasonal H3N2 viruses, rapid and reliable detection of newly emerging influenza reassortant viruses is important to enhance our influenza surveillance. A novel pyrosequencing assay was developed for the rapid identification and subtyping of potential human influenza A virus reassortants based on all eight gene segments of the virus. Except for HA and NA genes, one universal set of primers was used to amplify and subtype each of the six internal genes. With this method, all eight gene segments of 57 laboratory isolates and 17 original specimens of seasonal H1N1, H3N2 and 2009 H1N1 pandemic viruses were correctly matched with their corresponding subtypes. In addition, this method was shown to be capable of detecting reassortant viruses by correctly identifying the source of all 8 gene segments from three vaccine production reassortant viruses and three H1N2 viruses. In summary, this pyrosequencing assay is a sensitive and specific procedure for screening large numbers of viruses for reassortment events amongst the commonly circulating human influenza A viruses, which is more rapid and cheaper than using conventional sequencing approaches.

Potential for La Crosse virus segment reassortment in nature

Directory of Open Access Journals (Sweden)

Geske Dave

2008-12-01

Full Text Available Abstract The evolutionary success of La Crosse virus (LACV, family Bunyaviridae is due to its ability to adapt to changing conditions through intramolecular genetic changes and segment reassortment. Vertical transmission of LACV in mosquitoes increases the potential for segment reassortment. Studies were conducted to determine if segment reassortment was occurring in naturally infected Aedes triseriatus from Wisconsin and Minnesota in 2000, 2004, 2006 and 2007. Mosquito eggs were collected from various sites in Wisconsin and Minnesota. They were reared in the laboratory and adults were tested for LACV antigen by immunofluorescence assay. RNA was isolated from the abdomen of infected mosquitoes and portions of the small (S, medium (M and large (L viral genome segments were amplified by RT-PCR and sequenced. Overall, the viral sequences from 40 infected mosquitoes and 5 virus isolates were analyzed. Phylogenetic and linkage disequilibrium analyses revealed that approximately 25% of infected mosquitoes and viruses contained reassorted genome segments, suggesting that LACV segment reassortment is frequent in nature.

Rotavirus infection and the current status of rotavirus vaccines

Directory of Open Access Journals (Sweden)

Shou-Chien Chen

2012-04-01

Full Text Available Among children, rotaviruses are the most common cause of severe gastroenteritis worldwide and of diarrheal deaths in developing countries. Current vaccines (e.g., Rotarix, GlaxoSmithKline Biologicals; RotaTeq, Merck and Company effectively reduce rotaviral gastroenteritis, emergency department visits, and hospitalizations. The tremendous burden of rotavirus-related diarrhea in children across the world continues to drive the remarkable pace of vaccine development. This review assesses the global epidemiological and economic burden of rotavirus diseases, summarizes the relevant principles of the development of rotavirus vaccines, and presents data on the efficacy and effectiveness of currently licensed vaccines in both developed and developing countries.

Resource recovery of WC-Co cermet using hydrothermal oxidation technique

International Nuclear Information System (INIS)

Gao Ningfeng; Inagaki, F.; Sasai, R.; Itoh, H.; Watari, K.

2005-01-01

WC-Co cermet is widely used in industrial applications such as cutting tools, dies, wear parts and so on. It is of great importance to establish the recycling process for the precious metal resources contained in WC-Co cermet, because all these metals used in Japan are imported. In this paper we reported a hydrothermal oxidation technique using nitric acid for the reclamation of WC and Co. The WC-Co cermet specimens with various WC particle sizes and Co contents were hydrothermally treated in HNO 3 aqueous solutions at temperatures of 110-200 C for durations of 6-240 h. The Co was preferentially leached out into the acidic solution, while the WC was oxidized to insoluble WO 3 hydrate which was subsequently separated by filtration. The hydrothermal treatment parameters such as solvent concentrations, treatment temperatures, holding time were optimized in respect to different kinds of WC-Co cermets. A hydrothermal oxidation treatment in 3M HNO 3 aqueous solution at 150 C for 24 h was capable of fully disintegrating the cermet chip composed of coarse WC grains of 1-5 μm in size with 20 wt% of Co as binder. While the more oxidation resistant specimen composed of fine WC grains of 0.5-1.0 μm in size with 13 wt% of Co, was completely disintegrated by a treatment in 7 M HNO 3 aqueous solution at 170 C for 24 h. The filtered solid residues were composed of fine WO 3 .0.33H 2 O powder and a small amount of WO 3 . The recovered WO 3 .0.33H 2 O powder can be easily returned to the industrial process for the synthesis of WC powder so that the overall recycling cost can be possibly lowered. (orig.)

Direct laser sintered WC-10Co/Cu nanocomposites

Science.gov (United States)

Gu, Dongdong; Shen, Yifu

2008-04-01

In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa.

Direct laser sintered WC-10Co/Cu nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Gu Dongdong [College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)], E-mail: dongdonggu@nuaa.edu.cn; Shen Yifu [College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, 29 Yudao Street, Nanjing 210016 (China)

2008-04-30

In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa.

Direct laser sintered WC-10Co/Cu nanocomposites

International Nuclear Information System (INIS)

Gu Dongdong; Shen Yifu

2008-01-01

In the present work, the direct metal laser sintering (DMLS) process was used to prepare the WC-Co/Cu nanocomposites in bulk form. The WC reinforcing nanoparticles were added in the form of WC-10 wt.% Co composite powder. The microstructural features and mechanical properties of the laser-sintered sample were characterized by X-ray diffraction (XRD), atomic force microscope (AFM), scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), and nanoindentation tester. It showed that the original nanometric nature of the WC reinforcing particulates was well retained without appreciable grain growth after laser processing. A homogeneous distribution of the WC reinforcing nanoparticles with a coherent particulate/matrix interfacial bonding was obtained in the laser-sintered structure. The 94.3% dense nanocomposites have a dynamic nanohardness of 3.47 GPa and a reduced elastic modulus of 613.42 GPa

Impact of rotavirus vaccination on child mortality, morbidity, and rotavirus-related hospitalizations in Bolivia.

Science.gov (United States)

Inchauste, Lucia; Patzi, Maritza; Halvorsen, Kjetil; Solano, Susana; Montesano, Raul; Iñiguez, Volga

2017-08-01

The public health impact of rotavirus vaccination in countries with high child mortality rates remains to be established. The RV1 rotavirus vaccine was introduced in Bolivia in August 2008. This study describes the trends in deaths, hospitalizations, and healthcare visits due to acute gastroenteritis (AGE) and in rotavirus-related hospitalizations, among children rotavirus-related AGE was assessed using data from the active surveillance hospitals. Compared with the 2001-2008 pre-vaccine baseline, the mean number of rotavirus-related hospitalizations was reduced by 40.8% (95% confidence interval (CI) 21.7-66.4%) among children rotavirus disease. Over the post-vaccine period, changes in rotavirus epidemiology were observed, manifested by variations in seasonality and by a shift in the mean age of those with rotavirus infection. The significant decrease in main AGE-related health indicators in children rotavirus vaccine provides evidence of a substantial public health impact of rotavirus vaccination in Bolivia, as a measure for protecting children against AGE. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

FluReF, an automated flu virus reassortment finder based on phylogenetic trees.

Science.gov (United States)

Yurovsky, Alisa; Moret, Bernard M E

2011-01-01

Reassortments are events in the evolution of the genome of influenza (flu), whereby segments of the genome are exchanged between different strains. As reassortments have been implicated in major human pandemics of the last century, their identification has become a health priority. While such identification can be done "by hand" on a small dataset, researchers and health authorities are building up enormous databases of genomic sequences for every flu strain, so that it is imperative to develop automated identification methods. However, current methods are limited to pairwise segment comparisons. We present FluReF, a fully automated flu virus reassortment finder. FluReF is inspired by the visual approach to reassortment identification and uses the reconstructed phylogenetic trees of the individual segments and of the full genome. We also present a simple flu evolution simulator, based on the current, source-sink, hypothesis for flu cycles. On synthetic datasets produced by our simulator, FluReF, tuned for a 0% false positive rate, yielded false negative rates of less than 10%. FluReF corroborated two new reassortments identified by visual analysis of 75 Human H3N2 New York flu strains from 2005-2008 and gave partial verification of reassortments found using another bioinformatics method. FluReF finds reassortments by a bottom-up search of the full-genome and segment-based phylogenetic trees for candidate clades--groups of one or more sampled viruses that are separated from the other variants from the same season. Candidate clades in each tree are tested to guarantee confidence values, using the lengths of key edges as well as other tree parameters; clades with reassortments must have validated incongruencies among segment trees. FluReF demonstrates robustness of prediction for geographically and temporally expanded datasets, and is not limited to finding reassortments with previously collected sequences. The complete source code is available from http://lcbb.epfl.ch/software.html.

Observation of WC grain shapes determined by carbon content during liquid phase sintering of WC-Co alloys

International Nuclear Information System (INIS)

Sona Kim; Hyoun-Ee Kim; Seok-Hee Han; Jong-Ku Park

2001-01-01

In the composite materials of WC-Co alloys, the faceted WC grains as a hard phase are dispersed in the ductile matrix of cobalt. Properties of WC-Co alloys are affected by microstructural factors such as volume fraction of WC phase, size of WC grains, and carbon content (kinds of constituent phases). Although the properties of WC-Co alloys are inevitably affected by the shape of WC grains, the shape of WC grains has not been thrown light on the properties of WC-Co alloys yet, because it has been regarded to have a uniform shape regardless of alloy compositions. It is proved that the WC grains have various shapes varying reversibly with carbon content in the sintered WC-Co compacts. This dependency of grain shape on the carbon content is attributed to asymmetric atomic structure of WC crystal. The {10 1 - 0} prismatic planes are distinguished into two groups with different surface energy according to their atomic structures. The prismatic planes of high surface energy tend to disappear in the compacts with high carbon content. In addition, these high energy prismatic planes tend to split into low energy surfaces in the large WC grains. (author)

Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial.

Science.gov (United States)

Steele, Andrew Duncan; Neuzil, Kathleen M; Cunliffe, Nigel A; Madhi, Shabir A; Bos, Pieter; Ngwira, Bagrey; Witte, Desiree; Todd, Stacy; Louw, Cheryl; Kirsten, Mari; Aspinall, Sanet; Van Doorn, Leen Jan; Bouckenooghe, Alain; Suryakiran, Pemmaraju V; Han, Htay Htay

2012-09-13

Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children rotavirus vaccine Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Healthy infants aged 5-10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks) or three doses of Rotarix™ (together forming the pooled Rotarix™ group) or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443) were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6%) severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo) and G8 types (15 [1%] in placebo). Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%), 51.5% (95% CI:-6.5%; 77.9%) and 64.4% (95% CI: 17.1%; 85.2%), respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6%) severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo) and P[6] (13 [0.9%] in placebo). Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%), P[4] was 70.9% (95% CI: 37.5%; 87.0%) and P[6] was 55.2% (95% CI: -6

Current status of rotavirus vaccines.

Science.gov (United States)

Wang, Ching-Min; Chen, Shou-Chien; Chen, Kow-Tong

2015-11-01

Rotaviruses remain the major cause of childhood diarrheal disease worldwide and of diarrheal deaths of infants and children in developing countries. The huge burden of childhood rotavirus-related diarrhea in the world continues to drive the remarkable pace of vaccine development. Research articles were searched using terms "rotavirus" and "rotavirus vaccine" in MEDLINE and PubMed. Articles not published in the English language, articles without abstracts, and opinion articles were excluded from the review. After preliminary screening, all articles were reviewed and synthesized to provide an overview of current vaccines and vaccination programs. In this review of the global rotavirus vaccines and vaccination programs, the principles of rotavirus vaccine development and the efficacy of the currently licensed vaccines from both developed and developing countries were summarized. Rotavirus is a common cause of diarrhea in children in both developed and developing countries. Rotavirus vaccination is a cost-effective measure to prevent rotavirus diarrhea.

Rotavirus Infections

Science.gov (United States)

Rotavirus is a virus that causes gastroenteritis. Symptoms include severe diarrhea, vomiting, fever, and dehydration. Almost all ... the U.S. are likely to be infected with rotavirus before their 5th birthday. Infections happen most often ...

electropherotypes and subgroups of group a rotaviruses circulating ...

African Journals Online (AJOL)

Emmanuel Ameh

diarrhea caused by rotaviruses. The virus is a double stranded RNA (dsRNA) virus with 11 segments. Group A rotaviruses show a characteristic 4-2-3-2 pattern following electrophoresis. The VP6 subgroups, I and II exist. This work was carried out to study the prevalence of rotavirus infection among children 0-5 years with ...

Rotavirus Vaccines: a story of success with challenges ahead [version 1; referees: 3 approved

Directory of Open Access Journals (Sweden)

Miguel O’Ryan

2017-08-01

Full Text Available Approximately 40 years have passed since the discovery of the rotavirus and 10 years since the introduction and progressive dissemination of rotavirus vaccines worldwide. Currently, 92 countries have introduced rotavirus vaccines into national or subnational programs with evident impact in disease reduction. Two vaccines have been widely used, and four additional vaccines have been licensed and are being used in defined regions. In this context, one main issue that remains unsolved is the lower vaccine efficacy/effectiveness in low-income countries. An additional partially answered issue relates to rotavirus strain circulation in vaccinated populations. These issues are discussed in this review. The most imperative challenge ahead is to fulfill the WHO’s recommendation to introduce rotavirus vaccines in all countries.

Molecular Epidemiology of Rotavirus in Cats in the United Kingdom

Science.gov (United States)

Iturriza-Gómara, M.; Dove, W.; Sandrasegaram, M.; Nakagomi, T.; Nakagomi, O.; Cunliffe, N.; Radford, A. D.; Morgan, K. L.

2014-01-01

Rotaviruses are leading causes of gastroenteritis in the young of many species. Molecular epidemiological studies in children suggest that interspecies transmission contributes to rotavirus strain diversity in people. However, population-based studies of rotaviruses in animals are few. We investigated the prevalence, risk factors for infection, and genetic diversity of rotavirus A in a cross-sectional survey of cats housed within 25 rescue catteries across the United Kingdom. Morning litter tray fecal samples were collected during the winter and summer in 2012 from all pens containing kittens and a random sample of those housing adult cats. Group A rotavirus RNA was detected by real-time reverse transcription-PCR, and positive samples were G and P genotyped using nested VP4 and VP7 PCR assays. A total of 1,727 fecal samples were collected from 1,105 pens. Overall, the prevalence of rotavirus was 3.0% (95% confidence interval [CI], 1.2 to 4.9%). Thirteen out of 25 (52%; 95% CI, 31.3 to 72.2%) centers housed at least one rotavirus-positive cat. The prevalence of rotavirus was associated with season (odds ratio, 14.8 [95% CI, 1.1 to 200.4]; P = 0.04) but not age or diarrhea. It was higher during the summer (4.7%; 95% CI, 1.2 to 8.3%) than in winter (0.8%; 95% CI, 0.2 to 1.5%). Asymptomatic epidemics of infection were detected in two centers. G genotypes were characterized for 19 (33.3%) of the 57 rotavirus-positive samples and P genotypes for 36 (59.7%). Two rotavirus genotypes were identified, G3P[9] and G6P[9]. This is the first population-based study of rotavirus in cats and the first report of feline G6P[9], which questions the previous belief that G6P[9] in people is of bovine origin. PMID:25411173

Infiltration Behavior Of Mechanical Alloyed 75 wt% Cu-25 wt% WC Powders Into Porous WC Compacts

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Şelte A.

2015-06-01

Full Text Available In this work infiltration behavior of mechanical alloyed 75 wt% Cu – 25 wt% WC powders into porous WC compacts were studied. Owing to their ductile nature, initial Cu powders were directly added to mechanical alloying batch. On the other hand initial WC powders were high energy milled prior to mechanical alloying. Contact infiltration method was selected for densification and compacts prepared from processed powders were infiltrated into porous WC bodies. After infiltration, samples were characterized via X-Ray diffraction studies and microstructural evaluation of the samples was carried out via scanning electron microscopy observations. Based on the lack of solubility between WC and Cu it was possible to keep fine WC particles in Cu melt since solution reprecipitation controlled densification is hindered. Also microstructural characterizations via scanning electron microscopy confirmed that the transport of fine WC fraction from infiltrant to porous WC skeleton can be carried out via Cu melt flow during infiltration.

Rotavirus Infection in the Auckland Region After the Implementation of Universal Infant Rotavirus Vaccination: Impact on Hospitalizations and Laboratory Implications.

Science.gov (United States)

McAuliffe, Gary N; Taylor, Susan L; Drinković, Dragana; Roberts, Sally A; Wilson, Elizabeth M; Best, Emma J

2018-01-01

In July 2014, New Zealand introduced universal infant vaccination with RotaTeq (Merk & Co.) administered as 3 doses at 6 weeks, 3 and 5 months of age. We sought to assess the impact of rotavirus vaccination on gastroenteritis (GE) hospitalizations in the greater Auckland region and analyze changes in rotavirus testing in the period around vaccine introduction. Hospitalizations, laboratory testing rates and methods were compared between the pre-vaccine period (2009-2013), post-vaccine period (January 2015 to December 2015) and year of vaccine introduction (2014). There was a 68% decline in rotavirus hospitalizations of children Auckland region. However, continued rotavirus testing at pre-vaccine rates risks generating false positive results. Laboratories and clinicians should consider reviewing their testing algorithms before vaccine introduction.

Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial

Directory of Open Access Journals (Sweden)

Steele Andrew

2012-09-01

Full Text Available Abstract Background Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. Methods Healthy infants aged 5–10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks or three doses of Rotarix™ (together forming the pooled Rotarix™ group or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. Results Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443 were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6% severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo and G8 types (15 [1%] in placebo. Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%, 51.5% (95% CI:-6.5%; 77.9% and 64.4% (95% CI: 17.1%; 85.2%, respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6% severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo and P[6] (13 [0.9%] in placebo. Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%, P[4] was 70.9% (95% CI: 37.5%; 87

Effect of UV-irradiation on rotavirus

International Nuclear Information System (INIS)

Smirnov, Y.A.; Kapitulets, S.P.; Kaverin, N.V.; Amitina, N.N.; Ginevskaya, V.A.

1991-01-01

The effect of UV-irradiation on the infectivity of the SAll rotavirus was examined. The time behavior of the inactivation of infectivity generally exhibited the one-hit pattern. The effect was studied with respect to two phenomena, viz. the RNA-protein linkage and the formation of uracil dimers. To determine the number of the latter, purified 3 H-uridine-labelled rotavirus was exposed to UV radiation, and the RNA was extracted and analyzed by paper chromatography in the ascending mode. The formation of photodimers was found to be an important mechanism in the rotavirus inactivation on conventional irradiation, whereas RNA-protein linkages were observed on the application of high doses only. (author). 3 figs., 10 refs

Introduktion. Om rotavirus. Teknologi

DEFF Research Database (Denmark)

Wejse, Christian

2012-01-01

vil skyldes rotavirus. Typisk vil børnene få feber, opkastninger og/eller diarré. Sygdommen går sædvanligvis over af sig selv i løbet af 3 til 7 dage. Nogle børn får dog væske- og saltmangel i en sådan grad, at de må indlægges på hospital til behandling med drop og væske direkte ind i årerne. 85 – 90...... % af danske børn følger det danske børnevaccinationsprogram og bliver vaccineret mod en række infektioner. Der findes i Danmark to velafprøvede og godkendte vacciner mod rotavirus. Begge vacciner gives gennem munden og ikke gennem indsprøjtning i huden, som de øvrige vacciner i det danske...... børnevaccinationsprogram. Verdenssundhedsorganisation (WHO=World Health Organisation) samt nationale og europæiske faglige selskaber har anbefalet at vaccinere mod rotavirus. I en række europæiske lande er vaccination mod rotavirus indført i det nationale børnevaccinationsprogram. Andre europæiske lande har fravalgt...

Effects of WC Particle Size and Co Content on the Graded Structure in Functionally Gradient WC-Co Composites

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Yuan Yigao

2016-01-01

Full Text Available Functionally gradient WC-Co composites having a Co depleted surface zone and not comprising the h phase can be manufactured via carburizing process. During carburizing, besides carburizing process parameters, the microstructural parameters of WC-Co materials, such as WC grain size and Co content, also have significant influences on the formation of Co gradient structure. In this study, the effects of WC particle size and Co content on the gradient structure within gradient hardmetals have been studied, based on a series of carburizing experiments of WC-Co materials with different WC particle sizes and cobalt contents. The results show that both the thickness and the amplitude of the gradients within gradient WC-Co materials increase with increasing initial WC particle size and Co content of WC-Co alloys. The reason for this finding is discussed.

Efficacy of a monovalent human-bovine (116E) rotavirus vaccine in Indian infants: a randomised, double-blind, placebo-controlled trial.

Science.gov (United States)

Bhandari, Nita; Rongsen-Chandola, Temsunaro; Bavdekar, Ashish; John, Jacob; Antony, Kalpana; Taneja, Sunita; Goyal, Nidhi; Kawade, Anand; Kang, Gagandeep; Rathore, Sudeep Singh; Juvekar, Sanjay; Muliyil, Jayaprakash; Arya, Alok; Shaikh, Hanif; Abraham, Vinod; Vrati, Sudhanshu; Proschan, Michael; Kohberger, Robert; Thiry, Georges; Glass, Roger; Greenberg, Harry B; Curlin, George; Mohan, Krishna; Harshavardhan, G V J A; Prasad, Sai; Rao, T S; Boslego, John; Bhan, Maharaj Kishan

2014-06-21

Rotavirus is the most common cause of severe dehydrating gastroenteritis in developing countries. Safe, effective, and affordable rotavirus vaccines are needed in these countries. We aimed to assess the efficacy and tolerability of a monovalent human-bovine rotavirus vaccine for severe rotavirus gastroenteritis in low-resource urban and rural settings in India. We did a randomised double-blind, placebo-controlled, multicentre trial at three sites in Delhi (urban), Pune (rural), and Vellore (urban and rural) between March 11, 2011, and Nov 5, 2012. Infants aged 6-7 weeks were randomly assigned (2:1), via a central interactive voice or web response system with a block size of 12, to receive either three doses of oral human-bovine natural reassortant vaccine (116E) or placebo at ages 6-7 weeks, 10 weeks, and 14 weeks. Infants' families, study investigators, paediatricians in referral hospitals, laboratory staff, and committee members were all masked to treatment allocation. The primary outcome was incidence of severe rotavirus gastroenteritis (≥11 on the Vesikari scale). Efficacy outcomes and adverse events were ascertained through active surveillance. Analysis was by intention to treat and per protocol. The trial is registered with Clinical Trial Registry-India (CTRI/2010/091/000102) and ClinicalTrials.gov (NCT01305109). 4532 infants were assigned to receive the 116E vaccine and 2267 to receive placebo, of whom 4354 (96%) and 2187 (96%) infants, respectively, were included in the primary per-protocol efficacy analysis. 71 events of severe rotavirus gastroenteritis were reported in 4752 person-years in infants in the vaccine group compared with 76 events in 2360 person-years in those in the placebo group; vaccine efficacy against severe rotavirus gastroenteritis was 53·6% (95% CI 35·0-66·9; p=0·0013) and 56·4% (36·6-70·1; protavirus gastroenteritis episode was 55 (95% CI 37-97). The incidence of severe rotavirus gastroenteritis per 100 person-years was 1·5

Presencia de rotavirus en adultos con diarrea en Asunción, Paraguay Incidence of rotavirus in adults with diarrhea in Asunción, Paraguay

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M. Martínez

2005-06-01

Full Text Available Desde octubre de 2001 a marzo de 2004 se analizaron 533 heces de individuos mayores de 18 años con cuadros de diarrea, identificándose rotavirus en 92 (17,3% de ellas. La infección por rotavirus en adultos no mostró un grupo etáreo más afectado y se presentó a lo largo de todo el año sin diferencias significativas en las frecuencias trimestrales. En Paraguay, en los niños menores de 5 años, presenta un pico estacional entre los meses de junio y octubre. Los datos presentados refuerzan la necesidad de tener en cuenta a rotavirus en el diagnóstico diferencial de las diarreas en adultos.From October 2001 to March 2004, 92 out of 533 (17.3% fecal samples of patients over 18 years of age were positive for rotavirus. There were not differences of rotavirus incidence between age groups. Although in Paraguay, rotavirus infections in children less than 5 years old present a seasonal peak pattern (since June to October, in adults rotavirus was present throughout the year with the same frequency. Results presented here reinforce the notion that rotavirus should be considered in the differential diagnosis of diarrhea in adults.

Rotavirus morbidity and mortality in children in Brazil Morbilidad y mortalidad por rotavirus en niños en Brasil

Directory of Open Access Journals (Sweden)

Ana Marli Christovam Sartori

2008-02-01

Full Text Available OBJECTIVE: To study the epidemiology of rotavirus and estimate rotavirus-associated morbidity and mortality in children OBJETIVOS: Analizar la epidemiología del rotavirus y estimar la morbilidad y la mortalidad asociadas con las infecciones por rotavirus en niños < 5 años de edad en Brasil en 2004, antes de incluir la vacuna contra el rotavirus en el Programa Nacional de Inmunizaciones (PNI. MÉTODOS: Para estimar la morbilidad por rotavirus se revisaron los estudios publicados (1999-2006 que abordaban la incidencia de diarrea aguda en niños < 5 años de edad y la frecuencia de las infecciones por rotavirus en niños con diarrea en Brasil. Los casos de diarrea se dividieron en tres categorías de gravedad según el nivel de atención que requirieron: casos leves que solo requirieron atención domiciliaria, casos moderados que requirieron la visita a un servicio ambulatorio de salud y casos graves que requirieron hospitalización. Para estimar la mortalidad por rotavirus se utilizó el número de muertes registradas por diarrea en niños de < 5 años, según el Sistema de Información sobre Mortalidad (SIM del Sistema Único de Salud (SUS de Brasil, y se calculó la proporción de muertes causadas por este virus. RESULTADOS: Se estimó que las infecciones por rotavirus causan anualmente 3 525 053 casos de diarrea, 655 853 visitas a servicios ambulatorios de salud, 92 453 hospitalizaciones y 850 muertes en niños < 5 años de edad en Brasil. CONCLUSIONES: Las infecciones por rotavirus constituyen una importante causa de morbilidad y mortalidad en Brasil.

Global Seasonality of Rotavirus Disease

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Patel, Manish M.; Pitzer, Virginia; Alonso, Wladimir J.; Vera, David; Lopman, Ben; Tate, Jacqueline; Viboud, Cecile; Parashar, Umesh D.

2012-01-01

Background A substantial number of surveillance studies have documented rotavirus prevalence among children admitted for dehydrating diarrhea. We sought to establish global seasonal patterns of rotavirus disease before widespread vaccine introduction. Methods We reviewed studies of rotavirus detection in children with diarrhea published since 1995. We assessed potential relationships between seasonal prevalence and locality by plotting the average monthly proportion of diarrhea cases positive for rotavirus according to geography, country development, and latitude. We used linear regression to identify variables that were potentially associated with the seasonal intensity of rotavirus. Results Among a total of 99 studies representing all six geographical regions of the world, patterns of year-round disease were more evident in low- and low-middle income countries compared with upper-middle and high income countries where disease was more likely to be seasonal. The level of country development was a stronger predictor of strength of seasonality (P=0.001) than geographical location or climate. However, the observation of distinctly different seasonal patterns of rotavirus disease in some countries with similar geographical location, climate and level of development indicate that a single unifying explanation for variation in seasonality of rotavirus disease is unlikely. Conclusion While no unifying explanation emerged for varying rotavirus seasonality globally, the country income level was somewhat more predictive of the likelihood of having seasonal disease than other factors. Future evaluation of the effect of rotavirus vaccination on seasonal patterns of disease in different settings may help understand factors that drive the global seasonality of rotavirus disease. PMID:23190782

Human rotavirus genotypes circulating in Brazil before and after a nationwide rotavirus vaccination program established in 2006

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Caruzo TAR

2011-04-01

Full Text Available Thabata AR CaruzoGenetics, Evolution and Bioagents Department, Institute of Biology, State University of Campinas, Campinas, São Paulo, BrazilAbstract: Accounting for an estimated 600,000 deaths worldwide each year, rotaviruses are recognized as the most important etiologic agents causing severe acute gastroenteritis among children under the age of five years. In Brazil, until rotavirus vaccination was established in the public health system in 2006, acute gastroenteritis striking children under five years and caused by these viruses was clearly associated with 3.5 million episodes of diarrhea, 650,000 visits to outpatient health care facilities, 92,000 hospitalizations, and 850 deaths each year. After the introduction of the rotavirus vaccine in Brazil in March 2006, studies all over the country have been comparing rotavirus genotypes circulating in the recent pre- and postvaccination era. Most of these studies have reported a high prevalence of the G2P[4] genotype and also a decrease in rotavirus detection all over Brazil after the introduction of the vaccine. So far, these are preliminary studies, as a longer period of time is necessary to establish if this high prevalence of G2P[4] is due to selective pressure by the vaccine on the circulating viruses or to a normal genotype fluctuation, and if it will have any impact on vaccine efficacy in the future. This review describes results from the most recent studies addressing this issue and on rotavirus genotypic variability in Brazil.Keywords: human rotavirus, vaccine, genotypes, prevalence, Brazil

Silencing the alarms: innate immune antagonism by rotavirus NSP1 and VP3

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Morelli, Marco; Ogden, Kristen M.; Patton, John T.

2016-01-01

The innate immune response involves a broad array of pathogen sensors that stimulate the production of interferons (IFN) to induce an antiviral state. Rotavirus, a significant cause of childhood gastroenteritis and a member of the Reoviridae family of segmented, double-stranded RNA viruses, encodes at least two direct antagonists of host innate immunity: NSP1 and VP3. NSP1, a putative E3 ubiquitin ligase, mediates the degradation of cellular factors involved in both IFN induction and downstream signaling. VP3, the viral capping enzyme, utilizes a 2H-phosphodiesterase domain to prevent activation of the cellular oligoadenylate synthase (OAS)-RNase L pathway. Computational, molecular, and biochemical studies have provided key insights into the structural and mechanistic basis of innate immune antagonism by NSP1 and VP3 of group A rotaviruses (RVA). Future studies with non-RVA isolates will be essential to understand how other RV species evade host innate immune responses. PMID:25724417

Estimating rotavirus gastroenteritis hospitalisations by using hospital episode statistics before and after the introduction of rotavirus vaccine in Australia.

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Jayasinghe, Sanjay; Macartney, Kristine

2013-01-30

Hospital discharge records and laboratory data have shown a substantial early impact from the rotavirus vaccination program that commenced in 2007 in Australia. However, these assessments are affected by the validity and reliability of hospital discharge coding and stool testing to measure the true incidence of hospitalised disease. The aim of this study was to assess the validity of these data sources for disease estimation, both before and after, vaccine introduction. All hospitalisations at a major paediatric centre in children aged <5 years from 2000 to 2009 containing acute gastroenteritis (AGE) ICD 10 AM diagnosis codes were linked to hospital laboratory stool testing data. The validity of the rotavirus-specific diagnosis code (A08.0) and the incidence of hospitalisations attributable to rotavirus by both direct estimation and with adjustments for non-testing and miscoding were calculated for pre- and post-vaccination periods. A laboratory record of stool testing was available for 36% of all AGE hospitalisations (n=4948) the rotavirus code had high specificity (98.4%; 95% CI, 97.5-99.1%) and positive predictive value (96.8%; 94.8-98.3%), and modest sensitivity (61.6%; 58-65.1%). Of all rotavirus test positive hospitalisations only a third had a rotavirus code. The estimated annual average number of rotavirus hospitalisations, following adjustment for non-testing and miscoding was 5- and 6-fold higher than identified, respectively, from testing and coding alone. Direct and adjusted estimates yielded similar percentage reductions in annual average rotavirus hospitalisations of over 65%. Due to the limited use of stool testing and poor sensitivity of the rotavirus-specific diagnosis code routine hospital discharge and laboratory data substantially underestimate the true incidence of rotavirus hospitalisations and absolute vaccine impact. However, this data can still be used to monitor vaccine impact as the effects of miscoding and under-testing appear to be

Emergence of multiple clade 2.3.2.1 influenza A (H5N1) virus subgroups in Vietnam and detection of novel reassortants.

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Creanga, Adrian; Thi Nguyen, Diep; Gerloff, Nancy; Thi Do, Hoa; Balish, Amanda; Dang Nguyen, Hoang; Jang, Yunho; Thi Dam, Vui; Thor, Sharmi; Jones, Joyce; Simpson, Natosha; Shu, Bo; Emery, Shannon; Berman, LaShondra; Nguyen, Ha T; Bryant, Juliet E; Lindstrom, Steve; Klimov, Alexander; Donis, Ruben O; Davis, C Todd; Nguyen, Tung

2013-09-01

Phylogenetic analyses of 169 influenza A(H5N1) virus genomes were conducted for samples collected through active surveillance and outbreak responses in Vietnam between September 2010 and September 2012. While clade 1.1 viruses persisted in southern regions, three genetically distinct subgroups of clade 2.3.2.1 were found in northern and central Vietnam. The identification of each subgroup corresponded with detection of novel reassortants, likely due to their overlapping circulation throughout the country. While the previously identified clade 1.1 and A/Hubei/1/2010-like 2.3.2.1 genotypes remained the predominant viruses detected, four viruses were found to be reassortants between A/Hubei/1/2010-like (HA, NA, PB2, PB1, PA, NP) and A/duck/Vietnam/NCVD-885/2010-like (M, NS) viruses and one virus was identified as having A/duck/Vietnam/NCVD-885/2010-like HA, NA, PB1, and NP with A/Hubei/1/2010-like PB2 and PA genes. Additionally, clade 2.3.2.1 A/Hong Kong/6841/2010-like viruses, first detected in mid-2012, were identified as reassortants comprised of A/Hubei/1/2010-like PB2 and PA and A/duck/Vietnam/NCVD-885/2010-like PB1, NP, NA, M, NS genes. Published by Elsevier Inc.

Impact and cost-effectiveness of rotavirus vaccination in Bangladesh.

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Pecenka, Clint; Parashar, Umesh; Tate, Jacqueline E; Khan, Jahangir A M; Groman, Devin; Chacko, Stephen; Shamsuzzaman, Md; Clark, Andrew; Atherly, Deborah

2017-07-13

Diarrheal disease is a leading cause of child mortality globally, and rotavirus is responsible for more than a third of those deaths. Despite substantial decreases, the number of rotavirus deaths in children under five was 215,000 per year in 2013. Of these deaths, approximately 41% occurred in Asia and 3% of those in Bangladesh. While Bangladesh has yet to introduce rotavirus vaccination, the country applied for Gavi support and plans to introduce it in 2018. This analysis evaluates the impact and cost-effectiveness of rotavirus vaccination in Bangladesh and provides estimates of the costs of the vaccination program to help inform decision-makers and international partners. This analysis used Pan American Health Organization's TRIVAC model (version 2.0) to examine nationwide introduction of two-dose rotavirus vaccination in 2017, compared to no vaccination. Three mortality scenarios (low, high, and midpoint) were assessed. Benefits and costs were examined from the societal perspective over ten successive birth cohorts with a 3% discount rate. Model inputs were locally acquired and complemented by internationally validated estimates. Over ten years, rotavirus vaccination would prevent 4000 deaths, nearly 500,000 hospitalizations and 3 million outpatient visits in the base scenario. With a Gavi subsidy, cost/disability adjusted life year (DALY) ratios ranged from $58/DALY to $142/DALY averted. Without a Gavi subsidy and a vaccine price of $2.19 per dose, cost/DALY ratios ranged from $615/DALY to $1514/DALY averted. The discounted cost per DALY averted was less than the GDP per capita for nearly all scenarios considered, indicating that a routine rotavirus vaccination program is highly likely to be cost-effective. Even in a low mortality setting with no Gavi subsidy, rotavirus vaccination would be cost-effective. These estimates exclude the herd immunity benefits of vaccination, so represent a conservative estimate of the cost-effectiveness of rotavirus vaccination

Metal modified tungsten carbide (WC) for catalytic and electrocatalytic applications

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Mellinger, Zachary J.

One of the major challenges in the commercialization of proton exchange membrane fuel cells (PEMFC) is the cost, and low CO tolerance of the anode electrocatalyst material. The anode typically requires a high loading of precious metal electrocatalyst (Pt or Pt--Ru) to obtain a useful amount of electrical energy from the electrooxidation of methanol (CH3OH) or ethanol (C2H5OH). The complete electro--oxidation of methanol or ethanol on these catalysts produces strongly adsorbed CO on the surface, which reduces the activity of the Pt or Pt--Ru catalysts. Another major disadvantage of these electrocatalyst components is the scarcity and consequently high price of both Pt and Ru. Tungsten monocarbide (WC) has shown similar catalytic properties to Pt, leading to the utilization of WC and metal modified WC as replacements to Pt and Pt--Ru. In this thesis we investigated WC and Pt--modified WC as a potentially more CO--tolerant electrocatalysts as compared to pure Pt. These catalysts would reduce or remove the high loading of Pt used industrially. The binding energy of CO, estimated using temperature programmed desorption, is weaker on WC and Pt/WC than on Pt, suggesting that it should be easier to oxidize CO on WC and Pt/WC. This hypothesis was verified using cyclic voltammetry to compare the electro--oxidation of CO on WC, Pt/WC, and Pt supported on carbon substrates, which showed a lower voltage for the onset of oxidation of CO on WC and Pt/WC than on Pt. After observing these improved properties on the Pt/WC catalysts, we decided to expand our studies to investigate Pd--modified WC as Pd is less expensive than Pt and has shown more ideal properties for alcohol electrocatalysis in alkaline media. Pd/WC showed a lower binding energy of CO than both its parent metal Pd as well as Pt. Then, density functional theory (DFT) calculations were performed to determine how the presence of Pd affected the bonding of methanol and ethanol on the WC surface. The DFT studies showed

Clinical characteristics of rotavirus diarrhea in hospitalized Romanian infants.

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Lesanu, Gabriela; Becheanu, Cristina Adriana; Vlad, Raluca Maria; Pacurar, Daniela; Tincu, Iulia Florentina; Smadeanu, Roxana Elena

2013-01-01

Clinical characteristics of rotavirus enteritis were evaluated by comparison with acute diarrhea of other etiologies. We reviewed the medical records of children (aged 0-12 months) admitted with acute diarrhea in our hospital between January and December 2011. Of the 839 patients, 49.3% had rotavirus diarrhea. The incidence of severe disease was significantly higher for rotavirus diarrhea (65.2%, P < 0.01) than for other types of diarrheal disease.

Annual changes in rotavirus hospitalization rates before and after rotavirus vaccine implementation in the United States.

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Shah, Minesh P; Dahl, Rebecca M; Parashar, Umesh D; Lopman, Benjamin A

2018-01-01

Hospitalizations for rotavirus and acute gastroenteritis (AGE) have declined in the US with rotavirus vaccination, though biennial peaks in incidence in children aged less than 5 years occur. This pattern may be explained by lower rotavirus vaccination coverage in US children (59% to 73% from 2010-2015), resulting in accumulation of susceptible children over two successive birth cohorts. Retrospective cohort analysis of claims data of commercially insured US children aged rotavirus and for AGE from the 2002-2015 rotavirus seasons were examined. Median age and rotavirus vaccination coverage for biennial rotavirus seasons during pre-vaccine (2002-2005), early post-vaccine (2008-2011) and late post-vaccine (2012-2015) years. Age-stratified hospitalization rates decreased from pre-vaccine to early post-vaccine and then to late post-vaccine years. The clearest biennial pattern in hospitalization rates is the early post-vaccine period, with higher rates in 2009 and 2011 than in 2008 and 2010. The pattern diminishes in the late post-vaccine period. For rotavirus hospitalizations, the median age and the difference in age between biennial seasons was highest during the early post-vaccine period; these differences were not observed for AGE hospitalizations. There was no significant difference in vaccination coverage between biennial seasons. These observations provide conflicting evidence that incomplete vaccine coverage drove the biennial pattern in rotavirus hospitalizations that has emerged with rotavirus vaccination in the US. As this pattern is diminishing with higher vaccine coverage in recent years, further increases in vaccine coverage may reach a threshold that eliminates peak seasons in hospitalizations.

The Nature of Bonding in WC and WN

Institute of Scientific and Technical Information of China (English)

无

2001-01-01

The nature of bonding in the title compounds has been studied by using CASSCF and FOCl techniques. The ground states of WC and WN are found to be 3Δ and 4∑- state arising primarily from:...1σ2σ21π41δ13σ1 and ...1σ2σ21π41δ23σ1 configuration respectively. WC shows a strong character of covalent bond while WN have obvious character of ionic bond and the dissociation energy of WN is larger than that of WC (6.15 and 5.41 eV respective).

Simian rhesus rotavirus is a unique heterologous (non-lapine) rotavirus strain capable of productive replication and horizontal transmission in rabbits.

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Ciarlet, M; Estes, M K; Conner, M E

2000-05-01

Simian rhesus rotavirus (RRV) is the only identified heterologous (non-lapine) rotavirus strain capable of productive replication at a high inoculum dose of virus (>10(8) p.f.u.) in rabbits. To evaluate whether lower doses of RRV would productively infect rabbits and to obtain an estimate of the 50% infectious dose, rotavirus antibody-free rabbits were inoculated orally with RRV at inoculum doses of 10(3), 10(5) or 10(7) p.f.u. Based on faecal virus antigen or infectious virus shedding, RRV replication was observed with inoculum doses of 10(7) and 10(5) p.f.u., but not 10(3) p.f.u. Horizontal transmission of RRV to one of three mock-inoculated rabbits occurred 4-5 days after onset of virus antigen shedding in RRV-infected rabbits. Rabbits infected at 10(7) and 10(5), but not 10(3), p.f.u. of RRV developed rotavirus-specific immune responses and were completely (100%) protected from lapine ALA rotavirus challenge. These data confirm that RRV can replicate productively and spread horizontally in rabbits. In attempts to elucidate the genetic basis of the unusual replication efficacy of RRV in rabbits, the sequence of the gene encoding the lapine non-structural protein NSP1 was determined. Sequence analysis of the NSP1 of three lapine rotaviruses revealed a high degree of amino acid identity (85-88%) with RRV. Since RRV and lapine strains also share similar VP7s (96-97%) and VP4s (69-70%), RRV might replicate efficiently in rabbits because of the high relatedness of these three gene products, each implicated in host range restriction.

Development of primers for sequencing the NSP1, NSP3, and VP6 genes of the group A porcine rotavirus

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Fernanda Dornelas Florentino Silva

2014-02-01

Full Text Available Rotavirus is the causative pathogen of diarrhea in humans and in several animal species. Eight pairs of primers were developed and used for Sanger sequencing of the coding region of the NSP1, NSP3, and VP6 genes based on the conserved regions of the genome of the group A porcine rotavirus. Three samples previously screened as positive for group A rotaviruses were subjected to gene amplification and sequencing to characterize the pathogen. The information generated from this study is crucial for the understanding of the epidemiology of the disease.

An update of “Cost-effectiveness of rotavirus vaccination in the Netherlands: the results of a Consensus Rotavirus Vaccine model”

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Tu Hong Anh T

2013-01-01

Full Text Available Abstract Background To update a cost-effectiveness analysis of rotavirus vaccination in the Netherlands previously published in 2011. Methods The rotavirus burden of disease and the indirect protection of older children and young adults (herd protection were updated. Results When updated data was used, routine infant rotavirus vaccination in the Netherlands would potentially become an even more cost-effective strategy than previously estimated with the incremental cost per QALY at only €3,000-4,000. Break-even total vaccination costs were indicated at €92–122, depending on the applied threshold. Conclusions We concluded that the results on potentially favourable cost-effectiveness in the previous study remained valid, however, the new data suggested that previous results might represent an underestimation of the economic attractiveness of rotavirus vaccination.

Micromechanics of fracture in WC-Co hardmetals

International Nuclear Information System (INIS)

Dusza, J.; Parilak, L.

1986-01-01

A study has been made in WC-Co cemented carbides with grain sizes of 2.1 - 3.6 μm and 13 - 32 vol% Co, of the relationship between the fracture toughness and microstructural parameters and micromechanisms of fracture. Regression analyses have been used to derive empirical relationships between fracture toughness, and the binder spacing, the contiguity and the relative proportions of fracture in the binder phase and between contiguous WC grains

Molecular characterization of a human G20P[28] rotavirus a strain with multiple genes related to bat rotaviruses.

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Esona, Mathew D; Roy, Sunando; Rungsrisuriyachai, Kunchala; Gautam, Rashi; Hermelijn, Sandra; Rey-Benito, Gloria; Bowen, Michael D

2018-01-01

Group A rotaviruses are the major cause of severe gastroenteritis in the young of mammals and birds. This report describes characterization of an unusual G20P[28] rotavirus strain detected in a 24month old child from Suriname. Genomic sequence analyses revealed that the genotype constellation of the Suriname strain RVA/Human-wt/SUR/2014735512/2013/G20P[28] was G20-P[28]-I13-R13-C13-M12-A23-N13-T15-E20-H15. Genes VP1, VP2, VP3, NSP1, NSP2, NSP3, NSP4 and NSP5 were recently assigned novel genotypes by the Rotavirus Classification Working Group (RCWG). Three of the 11 gene segments (VP7, VP4, VP6) were similar to cognate gene sequences of bat-like human rotavirus strain Ecu534 from Ecuador and the VP7, NSP3 and NSP5 gene segments of strain RVA/Human-wt/SUR/2014735512/2013/G20P[28] were found to be closely related to gene sequences of bat rotavirus strain 3081/BRA detected in Brazil. Although distantly related, the VP1 gene of the study strain and bat strain BatLi09 detected in Cameroon in 2014 are monophyletic. The NSP1 gene was found to be most closely related to human strain QUI-35-F5 from Brazil. These findings suggest that strain RVA/Human-wt/SUR/2014735512/2013/G20P[28] represents a zoonotic infection from a bat host. Published by Elsevier B.V.

Implementation of Rotavirus Surveillance and Vaccine Introduction - World Health Organization African Region, 2007-2016.

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Mwenda, Jason M; Burke, Rachel M; Shaba, Keith; Mihigo, Richard; Tevi-Benissan, Mable Carole; Mumba, Mutale; Biey, Joseph Nsiari-Muzeyi; Cheikh, Dah; Poy MSc, Alain; Zawaira, Felicitas R; Aliabadi, Negar; Tate, Jacqueline E; Hyde, Terri; Cohen, Adam L; Parashar, Umesh D

2017-11-03

Rotavirus is a leading cause of severe pediatric diarrhea globally, estimated to have caused 120,000 deaths among children aged rotavirus vaccination for all infants worldwide (2). Two rotavirus vaccines are currently licensed globally: the monovalent Rotarix vaccine (RV1, GlaxoSmithKline; 2-dose series) and the pentavalent RotaTeq vaccine (RV5, Merck; 3-dose series). This report describes progress of rotavirus vaccine introduction (3), coverage (using estimates from WHO and the United Nations Children's Fund [UNICEF]) (4), and impact on pediatric diarrhea hospitalizations in the WHO African Region. By December 2016, 31 (66%) of 47 countries in the WHO African Region had introduced rotavirus vaccine, including 26 that introduced RV1 and five that introduced RV5. Among these countries, rotavirus vaccination coverage (completed series) was 77%, according to WHO/UNICEF population-weighted estimates. In 12 countries with surveillance data available before and after vaccine introduction, the proportion of pediatric diarrhea hospitalizations that were rotavirus-positive declined 33%, from 39% preintroduction to 26% following rotavirus vaccine introduction. These results support introduction of rotavirus vaccine in the remaining countries in the region and continuation of rotavirus surveillance to monitor impact.

Rotavirus diarrhea disease burden in Peru: the need for a rotavirus vaccine and its potential cost savings.

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Ehrenkranz, P; Lanata, C F; Penny, M E; Salazar-Lindo, E; Glass, R I

2001-10-01

To assess the disease burden of rotavirus diarrhea in Peru as well the need for and the potential cost savings with a rotavirus vaccine in that country. To assess the burden of rotavirus diarrhea in Peru, we reviewed published and unpublished reports where rotavirus was sought as the etiologic agent of diarrhea in children. Rotavirus detection rates obtained from these studies were combined with diarrhea incidence rates from a number of national surveys in order to estimate both the burden of rotavirus diarrhea in the country and its associated medical costs. Rotavirus is a significant cause of morbidity and mortality in Peruvian children. In their first 5 years of life, an estimated 1 in 1.6 children will experience an episode of rotavirus diarrhea, 1 in 9.4 will seek medical care, 1 in 19.7 will require hospitalization, and 1 in 375 will die of the disease. Per year, this represents approximately 384,000 cases, 64,000 clinic visits, 30,000 hospitalizations, and 1,600 deaths. The annual cost of medical care alone for these children is approximately US$ 2.6 million--and that does not take into account the indirect or societal costs of the illness and the deaths. Rotavirus immunization provides the prospect of decreasing the morbidity and mortality from diarrhea in Peru, but a vaccine regimen would have to be relatively inexpensive, a few dollars or less per child. Future cost-effectiveness analyses should explore the total costs (medical as well as indirect or societal) associated with rotavirus diarrhea. Newly licensed vaccines should be tested according to both their ability to avert deaths and their efficacy with fewer than three doses. All three of these factors could increase the cost savings associated with a rotavirus vaccine.

Rotavirus diarrhea disease burden in Peru: the need for a rotavirus vaccine and its potential cost savings

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Peter Ehrenkranz

2001-10-01

Full Text Available Objective. To assess the disease burden of rotavirus diarrhea in Peru as well the need for and the potential cost savings with a rotavirus vaccine in that country. Methods. To assess the burden of rotavirus diarrhea in Peru, we reviewed published and unpublished reports where rotavirus was sought as the etiologic agent of diarrhea in children. Rotavirus detection rates obtained from these studies were combined with diarrhea incidence rates from a number of national surveys in order to estimate both the burden of rotavirus diarrhea in the country and its associated medical costs. Results. Rotavirus is a significant cause of morbidity and mortality in Peruvian children. In their first 5 years of life, an estimated 1 in 1.6 children will experience an episode of rotavirus diarrhea, 1 in 9.4 will seek medical care, 1 in 19.7 will require hospitalization, and 1 in 375 will die of the disease. Per year, this represents approximately 384 000 cases, 64 000 clinic visits, 30 000 hospitalizations, and 1 600 deaths. The annual cost of medical care alone for these children is approximately US$ 2.6 million--and that does not take into account the indirect or societal costs of the illness and the deaths. Conclusions. Rotavirus immunization provides the prospect of decreasing the morbidity and mortality from diarrhea in Peru, but a vaccine regimen would have to be relatively inexpensive, a few dollars or less per child. Future cost-effectiveness analyses should explore the total costs (medical as well as indirect or societal associated with rotavirus diarrhea. Newly licensed vaccines should be tested according to both their ability to avert deaths and their efficacy with fewer than three doses. All three of these factors could increase the cost savings associated with a rotavirus vaccine.

Effectiveness of Monovalent and Pentavalent Rotavirus Vaccines in Guatemala.

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Gastañaduy, Paul A; Contreras-Roldán, Ingrid; Bernart, Chris; López, Beatriz; Benoit, Stephen R; Xuya, Marvin; Muñoz, Fredy; Desai, Rishi; Quaye, Osbourne; Tam, Ka Ian; Evans-Bowen, Diana K; Parashar, Umesh D; Patel, Manish; McCracken, John P

2016-05-01

Concerns remain about lower effectiveness and waning immunity of rotavirus vaccines in resource-poor populations. We assessed vaccine effectiveness against rotavirus in Guatemala, where both the monovalent (RV1; 2-dose series) and pentavalent (RV5; 3-dose series) vaccines were introduced in 2010. A case-control evaluation was conducted in 4 hospitals from January 2012 to August 2013. Vaccine status was compared between case patients (children with laboratory-confirmed rotavirus diarrhea) and 2 sets of controls: nondiarrhea "hospital" controls (matched by birth date and site) and nonrotavirus "test-negative" diarrhea controls (adjusted for age, birth month/year, and site). Vaccine effectiveness ([1 - odds ratio of vaccination] × 100%) was computed using logistic regression models. We evaluated 213 case patients, 657 hospital controls, and 334 test-negative controls. Effectiveness of 2-3 doses of a rotavirus vaccine against rotavirus requiring emergency department visit or hospitalization was 74% (95% confidence interval [CI], 58%-84%) with hospital controls, and 52% (95% CI, 26%-69%) with test-negative controls. Using hospital controls, no significant difference in effectiveness was observed between infants 6-11 months (74% [95% CI, 18%-92%]) and children ≥12 months of age (71% [95% CI, 44%-85%]) (P= .85), nor between complete courses of RV1 (63% [95% CI, 23%-82%]) and RV5 (69% [95% CI, 29%-87%]) (P= .96). An uncommon G12P[8] strain, partially heterotypic to strains in both vaccines, was identified in 89% of cases. RV1 and RV5 were similarly effective against severe rotavirus diarrhea caused by a heterotypic strain in Guatemala. This supports broader implementation of rotavirus vaccination in low-income countries where >90% global deaths from rotavirus occur. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Protect Your Child from Rotavirus Disease

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... Submit What's this? Submit Button Past Emails Prevent Rotavirus Language: English (US) Español (Spanish) Recommend on Facebook ... likely to get rotavirus from December to June. Rotavirus Can Cause Dehydration Symptoms of Dehydration Decrease in ...

Completion report for the isolation and remediation of inactive liquid low-level radioactive waste tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 at Oak Ridge National Laboratory Oak Ridge, Tennessee

International Nuclear Information System (INIS)

1997-12-01

The Federal Facility Agreement (FFA) between the U.S. Environmental Protection Agency (EPA), Tennessee Department of Environment and Conservation (TDEC), and U.S. Department of Energy (DOE) requires that all liquid low-level waste tanks at Oak Ridge National Laboratory removed from service, designated in the FFA as Category D, be remediated in accordance with Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) requirements. A human health risk screening assessment was conducted for inactive Tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 as part of an evaluation to determine the method of remediation necessary to safely and permanently isolate and remediate the tanks. Risk screening assessment results indicated that the health risks associated with these tanks were within or below the EPA range of concern of 1 x 10 -4 to 1 x 10 -6 . On the basis of these results and with regulators concurrence, it was determined that either no action or in-place stabilization of the tanks would satisfy risk-based remediation goals. Therefore, decisions were made and approved by DOE to remediate these tanks in-place as maintenance actions rather than actions under the CERCLA process. Letters documenting these decisions were approved by DOE and subsequently submitted to TDEC and EPA, who concurred with the maintenance actions. Tanks WC-5, WC-6, WC-8, WC-19, 3002-A, 7560, and 7562 were isolated from associated piping, electrical systems, and instrumentation and were grouted in-place. Tank 7562 was originally isolated from associated piping and instrumentation and left in-place empty for future remedial consideration. Upon further consideration, the decision was made by DOE, with concurrence by the regulators, to complete the maintenance action of Tank 7562 by grouting it in-place in March 1997

Reaching every child with rotavirus vaccine: Report from the 10th African rotavirus symposium held in Bamako, Mali.

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Sow, Samba O; Steele, A Duncan; Mwenda, Jason M; Armah, George E; Neuzil, Kathleen M

2017-10-09

The Center for Vaccine Development - Mali (CVD - Mali), the World Health Organization's regional office in Africa (WHO/AFRO), and the CVD at the University of Maryland School of Medicine hosted the 10th African Rotavirus Symposium in Bamako, Mali on 1-2 June 2016. The symposium is coordinated by WHO/AFRO, the Regional Rotavirus Reference Laboratories, and the African Rotavirus Network (ARN), with support from the Bill & Melinda Gates Foundation. The event brings together leading rotavirus researchers, scientists, and policy-makers from across Africa and the world. Over 150 participants, from 31 countries, including 27 in Africa, joined forces to address the theme "Reaching Every Child in Africa with Rotavirus Vaccines." This symposium, the first in francophone Africa, occurred at an unprecedented time when 33 African countries had introduced rotavirus vaccines into their national immunization programs. The symposium concluded with a Call to Action to introduce rotavirus vaccines in the 21 remaining African countries, to increase access in countries with existing vaccination programs, and to continue surveillance and research on rotavirus and other diarrheal diseases. Copyright © 2017.

Reactive Sintering of Bimodal WC-Co Hardmetals

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Marek Tarraste

2015-09-01

Full Text Available Bimodal WC-Co hardmetals were produced using novel technology - reactive sintering. Milled and activated tungsten and graphite powders were mixed with commercial coarse grained WC-Co powder and then sintered. The microstructure of produced materials was free of defects and consisted of evenly distributed coarse and fine tungsten carbide grains in cobalt binder. The microstructure, hardness and fracture toughness of reactive sintered bimodal WC-Co hardmetals is exhibited. Developed bimodal hardmetal has perspective for demanding wear applications for its increased combined hardness and toughness. Compared to coarse material there is only slight decrease in fracture toughness (K1c is 14.7 for coarse grained and 14.4 for bimodal, hardness is increased from 1290 to 1350 HV units.DOI: http://dx.doi.org/10.5755/j01.ms.21.3.7511

Immunogenicity and protective efficacy of yeast extracts containing rotavirus-like particles: a potential veterinary vaccine.

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Rodríguez-Limas, William A; Pastor, Ana Ruth; Esquivel-Soto, Ernesto; Esquivel-Guadarrama, Fernando; Ramírez, Octavio T; Palomares, Laura A

2014-05-19

Rotavirus is the most common cause of severe diarrhea in many animal species of economic interest. A simple, safe and cost-effective vaccine is required for the control and prevention of rotavirus in animals. In this study, we evaluated the use of Saccharomyces cerevisiae extracts containing rotavirus-like particles (RLP) as a vaccine candidate in an adult mice model. Two doses of 1mg of yeast extract containing rotavirus proteins (between 0.3 and 3 μg) resulted in an immunological response capable of reducing the replication of rotavirus after infection. Viral shedding in all mice groups diminished in comparison with the control group when challenged with 100 50% diarrhea doses (DD50) of murine rotavirus strain EDIM. Interestingly, when immunizing intranasally protection against rotavirus infection was observed even when no increase in rotavirus-specific antibody titers was evident, suggesting that cellular responses were responsible of protection. Our results indicate that raw yeast extracts containing rotavirus proteins and RLP are a simple, cost-effective alternative for veterinary vaccines against rotavirus. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Nosocomial rotavirus gastroenteritis].

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Marinosci, A; Doit, C; Koehl, B; Belhacel, K; Mariani Kurkdjian, P; Melki, I; Renaud, A; Lemaitre, C; Ammar Khodja, N; Blachier, A; Bonacorsi, S; Faye, A; Lorrot, M

2016-11-01

Rotavirus is the most common cause of gastroenteritis in children requiring hospitalization. It is a very resistant and contagious virus causing nosocomial gastroenteritis. In France, the vaccine against rotavirus has been available since 2006, but the vaccine is not recommended for infant vaccination. The aim of this retrospective study was to describe nosocomial rotavirus gastroenteritis (NRGE) and to assess its impact on children hospitalized in the General Pediatrics Department of Robert-Debré Hospital (Paris) between 1 January 2009 and 31 December 2013. We analyzed the demographic characteristics of children (age, term birth, underlying diseases) and the severity of the NRGE (oral or intravenous hydration), and assessed whether these children could benefit from vaccination against rotavirus. One hundred thirty-six children presented nosocomial rotavirus infection, with an incidence of 2.5 NRGE per 1000 days of hospitalization. The incidence of NRGE was stable between 2009 and 2013 despite the introduction of specific hygiene measures. The average age of the children was 7 months (range: 0.5-111 months). Most often NRGE occurred in children hospitalized for respiratory diseases (65% of cases) and requiring prolonged hospitalization (median: 18 days). One-third of children were born premature (25%). Hydration was oral in 80 patients (59%), by intravenous infusion in 18 patients (13%), and intraosseous in one patient. Half of the patients were aged less than 5 months and could benefit from the protection afforded by vaccination. NRGE are common. Rotavirus mass vaccination should have a positive impact on the incidence of NRGE by reducing the number of children hospitalized for gastroenteritis, therefore indirectly reducing the number of hospital cross-infections of hospitalized children who are too young to be vaccinated. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi

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Nakagomi, Toyoko; Nakagomi, Osamu; Dove, Winifred; Doan, Yen Hai; Witte, Desiree; Ngwira, Bagrey; Todd, Stacy; Steele, A Duncan; Neuzil, Kathleen M; Cunliffe, Nigel A

2014-01-01

The human, G1P[8] rotavirus vaccine (Rotarix) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere. The aim of this study was to examine the molecular relationships of circulating wild-type rotaviruses detected during the clinical trial in Malawi to RIX4414 (the strain contained in Rotarix) and to common human rotavirus strains. Of 88 rotavirus-positive, diarrhoeal stool specimens, 43 rotaviruses exhibited identifiable RNA migration patterns when examined by polyacrylamide gel electrophoresis. The genes encoding VP7, VP4, VP6 and NSP4 of 5 representative strains possessing genotypes G12P[6], G1P[8], G9P[8], and G8P[4] were sequenced. While their VP7 (G) and VP4 (P) genotype designations were confirmed, the VP6 (I) and NSP4 (E) genotypes were either I1E1 or I2E2, indicating that they were of human rotavirus origin. RNA-RNA hybridization using 21 culture-adapted strains showed that Malawian rotaviruses had a genomic RNA constellation common to either the Wa-like or DS-1 like human rotaviruses. Overall, the Malawi strains appear similar in their genetic make-up to rotaviruses described in countries where vaccine efficacy is greater, suggesting that the lower efficacy in Malawi is unlikely to be explained by the diversity of circulating strains. PMID:22520123

Identification of reassortant pandemic H1N1 influenza virus in Korean pigs.

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Han, Jae Yeon; Park, Sung Jun; Kim, Hye Kwon; Rho, Semi; Nguyen, Giap Van; Song, Daesub; Kang, Bo Kyu; Moon, Hyung Jun; Yeom, Min Joo; Park, Bong Kyun

2012-05-01

Since the 2009 pandemic human H1N1 influenza A virus emerged in April 2009, novel reassortant strains have been identified throughout the world. This paper describes the detection and isolation of reassortant strains associated with human pandemic influenza H1N1 and swine influenza H1N2 (SIV) viruses in swine populations in South Korea. Two influenza H1N2 reassortants were detected, and subtyped by PCR. The strains were isolated using Madin- Darby canine kidney (MDCK) cells, and genetically characterized by phylogenetic analysis for genetic diversity. They consisted of human, avian, and swine virus genes that were originated from the 2009 pandemic H1N1 virus and a neuraminidase (NA) gene from H1N2 SIV previously isolated in North America. This identification of reassortment events in swine farms raises concern that reassortant strains may continuously circulate within swine populations, calling for the further study and surveillance of pandemic H1N1 among swine.

Evidence for presumable feline origin of sporadic G6P[9] rotaviruses in humans.

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Pietsch, Corinna; Liebert, Uwe G

2018-05-31

Species A rotaviruses are highly diverse and impose a substantial burden to human and animal health. Interspecies transmission between livestock, domestic animals and humans is commonly observed, but spread of animal-like rotaviruses within the human population is limited. During the continued monitoring of rotavirus strains in Germany, an unusual G6P[9] rotavirus strain was detected in feces of a child. The complete rotavirus coding sequences revealed a unique G6-P[9]-I2-R2-C2-M2-A3-N2-T3-E2-H3 genotype constellation. The virus was phylogenetically related to feline G3P[9] strains and other human G6P[9] rotaviruses of presumable zoonotic origin. Analysis of primer binding sites of G6 specific genotyping revealed further evidence of a G6P[9] feline reservoir. Moreover, substantial deficits of conventional semi-nested PCR genotyping approaches in detecting contemporary G6P[9] were revealed. Rotavirus strain GER29-14 most likely resulted from a direct or recent interspecies transmission from a cat to human. Further studies could assess nucleic acid sequences and genotype constellations of feline rotavirus to confirm the likely feline origin of sporadic human G6P[9] strains. Copyright © 2018 Elsevier B.V. All rights reserved.

Cryptosporidium spp. and rotavirus gastroenteritis and change of incidence after rotavirus vaccination among children in Raparin Pediatrics Hospital, Erbil, Iraq

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Sally S. Azeez

2017-11-01

Full Text Available Background: Watery diarrhea is the most common medical problem among infants and young children, caused by different microbial etiology including Cryptosporidium spp. and rotavirus, which are usually misdiagnosed in conventional stool test. This study aimed to investigate the incidence of Cryptosporidium and rotavirus gastroenteritis among children in Erbil as well as evaluate the efficacy of rotavirus vaccination procedure applied in Erbil.Methods: Fecal specimens were collected from 400 children (boys and girls, aged one month to five years old, who attended Raparin Pediatrics Hospital in Erbil complaining from diarrhea, between January to August 2014. Modified Ziehl Neelsen technique and nested PCR were used for detection of cryptosporidiosis while rotavirus infection was detected by rapid CerTest.Results: Rate of detection of cryptosporidiosis was remarkably higher using PCR than Ziehl-Neelsen stain (0% versus 6%, and the infection was slightly higher among boys (6.25% vs 5.55% and children ≤2 years (11.7%. The peak of infection reached during spring season (March and April (9.5%. The detection rate of rotavirus was 32.0%, which was slightly higher among males (34.4% vs 30.0% and in children between one to three years old (39.3%. The highest detection rate (38.6% was recorded during winter season (January and February. The infection was significantly higher among non-vaccinated children (65.9% vs 14.1%; p<0.05.Conclusion: The incidence of cryptosporidiosis is declining. However, rotavirus gastroenteritis was relatively high among young children in Erbil. Rotateq vaccine significantly reduced the incidence of rotavirus infection.

Epidemiological investigation of rotavirus infection in buffalo calves in Bangladesh

International Nuclear Information System (INIS)

Samad, M.A.; Ahmed, M.W.

1990-01-01

A study on rotavirus infection in buffalo calves in Bangladesh was carried out to detect its association with diarrhoea. An overall 28% incidence of diarrhoeal diseases was recorded in rural buffalo calves. Rotavirus was detected in faecal samples from both diarrhoeic (12%) and non-diarrhoeic (3%) calves by enzyme linked immunosorbent assay. An association between diarrhoea and rotavirus infection was recorded in buffalo calves below 1 month of age in both diarrhoeic (27%) and non-diarrhoeic (7%) calves. Rotavirus infection in diarrhoeic buffalo calves was found to be highest in winter (16.7%), followed by summer (9.1%) and lowest in the rainy season (7.7%). Further studies on the epidemiological and prophylactic aspects of rotavirus infection should be conducted to control this infection in Bangladesh. (author). 21 refs, 2 tabs

Rotavirus Infections - Multiple Languages

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... Are Here: Home → Multiple Languages → All Health Topics → Rotavirus Infections URL of this page: https://medlineplus.gov/ ... V W XYZ List of All Topics All Rotavirus Infections - Multiple Languages To use the sharing features ...

Contribution to the quantum study of neutral tungsten carbide WC and ionized (WC"q"+, q=1 and 2)

International Nuclear Information System (INIS)

Sabor, Said

2015-01-01

Metal carbides and oxides are more interesting in catalytic and industrial domains. Tungsten carbide WC has been detected as serious substituent of platinum Pt catalytic. The ultimate goal of this thesis is theoretical studies of electronic structure, stability and the bound nature on WC, WO and its cations. Our preliminary research were motivated by the available spectroscopic data on W, W"+, W"2"+, WC and WC"2"+. We used the methodology (CASSCF/MRCI/MRCI+Q/aug-cc-pV5Z(-PP)) implemented on MOLPRO package to perform quantum calculations with high accuracy taking into account the correlation and relativistic effects with a specific treatment of spin orbit coupling for some low lying excited electronic states of WC"n"+, (n=0, 1 et 2). Our results are shown in good agreement with those available in the literature. Furthermore, in this work for the first time we demonstrated that a carbide dication (WC"2"+) is thermodynamically stable. (author) [fr

Effectiveness of Pentavalent Rotavirus Vaccine Under Conditions of Routine Use in Rwanda.

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Tate, Jacqueline E; Ngabo, Fidele; Donnen, Philippe; Gatera, Maurice; Uwimana, Jeannine; Rugambwa, Celse; Mwenda, Jason M; Parashar, Umesh D

2016-05-01

Rotavirus vaccine efficacy is lower in low-income countries than in high-income countries. Rwanda was one of the first low-income countries in sub-Saharan Africa to introduce rotavirus vaccine into its national immunization program. We sought to evaluate rotavirus vaccine effectiveness (VE) in this setting. VE was assessed using a case-control design. Cases and test-negative controls were children who presented with a diarrheal illness to 1 of 8 sentinel district hospitals and 10 associated health centers and had a stool specimen that tested positive (cases) or negative (controls) for rotavirus by enzyme immunoassay. Due to high vaccine coverage almost immediately after vaccine introduction, the analysis was restricted to children 7-18 weeks of age at time of rotavirus vaccine introduction. VE was calculated as (1 - odds ratio) × 100, where the odds ratio was the adjusted odds ratio for the rotavirus vaccination rate among case-patients compared with controls. Forty-eight rotavirus-positive and 152 rotavirus-negative children were enrolled. Rotavirus-positive children were significantly less likely to have received rotavirus vaccine (33/44 [73%] unvaccinated) compared with rotavirus-negative children (81/136 [59%] unvaccinated) (P= .002). A full 3-dose series was 75% (95% confidence interval [CI], 31%-91%) effective against rotavirus gastroenteritis requiring hospitalization or a health center visit and was 65% (95% CI, -80% to 93%) in children 6-11 months of age and 81% (95% CI, 25%-95%) in children ≥12 months of age. Rotavirus vaccine is effective in preventing rotavirus disease in Rwandan children who began their rotavirus vaccine series from 7 to 18 weeks of age. Protection from vaccination was sustained after the first year of life. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Cost-effectiveness of Rotavirus vaccination in Vietnam

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Goldie Sue J

2009-01-01

Full Text Available Abstract Background Rotavirus is the most common cause of severe diarrhea leading to hospitalization or disease-specific death among young children. New rotavirus vaccines have recently been approved. Some previous studies have provided broad qualitative insights into the health and economic consequences of introducing the vaccines into low-income countries, representing several features of rotavirus infection, such as varying degrees of severity and age-dependency of clinical manifestation, in their model-based analyses. We extend this work to reflect additional features of rotavirus (e.g., the possibility of reinfection and varying degrees of partial immunity conferred by natural infection, and assess the influence of the features on the cost-effectiveness of rotavirus vaccination. Methods We developed a Markov model that reflects key features of rotavirus infection, using the most recent data available. We applied the model to the 2004 Vietnamese birth cohort and re-evaluated the cost-effectiveness (2004 US dollars per disability-adjusted life year [DALY] of rotavirus vaccination (Rotarix® compared to no vaccination, from both societal and health care system perspectives. We conducted univariate sensitivity analyses and also performed a probabilistic sensitivity analysis, based on Monte Carlo simulations drawing parameter values from the distributions assigned to key uncertain parameters. Results Rotavirus vaccination would not completely protect young children against rotavirus infection due to the partial nature of vaccine immunity, but would effectively reduce severe cases of rotavirus gastroenteritis (outpatient visits, hospitalizations, or deaths by about 67% over the first 5 years of life. Under base-case assumptions (94% coverage and $5 per dose, the incremental cost per DALY averted from vaccination compared to no vaccination would be $540 from the societal perspective and $550 from the health care system perspective. Conclusion

Molecular characterization of rotavirus strains detected during a clinical trial of a human rotavirus vaccine in Blantyre, Malawi.

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Nakagomi, Toyoko; Nakagomi, Osamu; Dove, Winifred; Doan, Yen Hai; Witte, Desiree; Ngwira, Bagrey; Todd, Stacy; Duncan Steele, A; Neuzil, Kathleen M; Cunliffe, Nigel A

2012-04-27

The human, G1P[8] rotavirus vaccine (Rotarix™) significantly reduced severe rotavirus gastroenteritis episodes in a clinical trial in South Africa and Malawi, but vaccine efficacy was lower in Malawi (49.5%) than reported in South Africa (76.9%) and elsewhere. The aim of this study was to examine the molecular relationships of circulating wild-type rotaviruses detected during the clinical trial in Malawi to RIX4414 (the strain contained in Rotarix™) and to common human rotavirus strains. Of 88 rotavirus-positive, diarrhoeal stool specimens, 43 rotaviruses exhibited identifiable RNA migration patterns when examined by polyacrylamide gel electrophoresis. The genes encoding VP7, VP4, VP6 and NSP4 of 5 representative strains possessing genotypes G12P[6], G1P[8], G9P[8], and G8P[4] were sequenced. While their VP7 (G) and VP4 (P) genotype designations were confirmed, the VP6 (I) and NSP4 (E) genotypes were either I1E1 or I2E2, indicating that they were of human rotavirus origin. RNA-RNA hybridization using 21 culture-adapted strains showed that Malawian rotaviruses had a genomic RNA constellation common to either the Wa-like or the DS-1 like human rotaviruses. Overall, the Malawi strains appear similar in their genetic make-up to rotaviruses described in countries where vaccine efficacy is greater, suggesting that the lower efficacy in Malawi is unlikely to be explained by the diversity of circulating strains. Copyright © 2011 Elsevier Ltd. All rights reserved.

Phase composition and microstructure of WC-Co alloys obtained by selective laser melting

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Khmyrov, Roman S.; Shevchukov, Alexandr P.; Gusarov, Andrey V.; Tarasova, Tatyana V.

2018-03-01

Phase composition and microstructure of initial WC, BK8 (powder alloy 92 wt.% WC-8 wt.% Co), Co powders, ball-milled powders with four different compositions (1) 25 wt.% WC-75 wt.% Co, (2) 30 wt.% BK8-70 wt.% Co, (3) 50 wt.% WC-50 wt.% Co, (4) 94 wt.% WC-6 wt.% Co, and bulk alloys obtained by selective laser melting (SLM) from as-milled powders in as-melted state and after heat treatment were investigated by scanning electron microscopy and X-ray diffraction analysis. Initial and ball-milled powders consist of WC, hexagonal α-Co and face-centered cubic β-Co. The SLM leads to the formation of major new phases W3Co3C, W4Co2C and face-centered cubic β-Co-based solid solution. During the heat treatment, there occurs partial decomposition of the face-centered cubic β-Co-based solid solution with the formation of W2C and hexagonal α-Co solid solution. The microstructure of obtained bulk samples, in general, corresponds to the observed phase composition.

Rotavirus mortality confirmed by etiologic identification in Venezuelan children with diarrhea.

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Pérez-Schael, Irene; Salinas, Belén; González, Rosabel; Salas, Hans; Ludert, Juan Ernesto; Escalona, Marisol; Alcalá, Ana; Rosas, María Alejandra; Materán, Mercedes

2007-05-01

Hospital-based studies to determine the etiology of deaths from diarrhea are scarce. In this study, we specifically analyzed deaths due to rotavirus to assess the rotavirus impact on diarrhea mortality. To determine the rotavirus proportion contributing to mortality due to diarrhea, we analyzed data obtained from a hospital-based mortality surveillance, conducted over 7 years, in the Ciudad Hospitalaria Dr. Enrique Tejera, Valencia, Venezuela. Rotavirus was identified in stool samples collected from children who died of diarrhea, by a confirmatory ELISA and/or reverse transcription polymerase chain reaction. Our results show that rotavirus (21%; 21/100) is the leading cause of death due to diarrhea among children causes in this age group. Shigella spp. (19%; 13/69) was the second most important cause of death, followed by calicivirus (6%; 3/53). Furthermore, this study documents a seasonal pattern in the deaths due to rotavirus (odds ratio 3.28; 95% confidence interval 1.13-9.76). For Venezuela, it is estimated that approximately 300 children cause of death due to diarrhea, which supports previous estimations. This is the first study to present data of cause-specific mortality due to diarrhea based on hospital surveillance of diarrhea etiologies.

Rotavirus antigenemia in children is associated with viremia.

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Sarah E Blutt

2007-04-01

Full Text Available Antigenemia is commonly detected in rotavirus-infected children. Although rotavirus RNA has been detected in serum, definitive proof of rotavirus viremia has not been shown. We aimed to analyze a defined patient population to determine if infectious virus could be detected in sera from children with rotavirus antigenemia.Serum samples obtained upon hospitalization from children with gastroenteritis (57 stool rotavirus-positive and 41 rotavirus-negative, children with diagnosed bronchiolitis of known (n = 58 or unknown (n = 17 viral etiology, children with noninfectious, nonchronic conditions (n = 17, and healthy adults (n = 28 were tested for rotavirus antigen by enzyme immunoassay (EIA. Results of serum antigen testing were assessed for association with clinical and immunological attributes of the children. Rotavirus antigenemia was detected in 90% (51/57 of children with rotavirus-positive stools, in 89% (8/9 of children without diarrhea but with rotavirus-positive stools, in 12% (2/17 of children with bronchiolitis of unknown etiology without gastroenteritis, and in 12% (5/41 of children with gastroenteritis but with rotavirus-negative stools. Antigenemia was not detected in sera from children with noninfectious nonchronic conditions, children with bronchiolitis of known etiology and no gastroenteritis, or healthy adults. Neither age nor timing of serum collection within eight days after onset of gastroenteritis significantly affected levels of antigenemia, and there was no correlation between antigenemia and viral genotype. However, there was a negative correlation between serum rotavirus antigen and acute rotavirus-specific serum IgA (r = -0.44, p = 0.025 and IgG (r = -0.40, p = 0.01 titers. We examined 11 antigen-positive and nine antigen-negative sera for infectious virus after three blind serial passages in HT-29 cells using immunofluorescence staining for rotavirus structural and nonstructural proteins. Infectious virus was detected in

Rotavirus Antigenemia in Children Is Associated with Viremia

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Blutt, Sarah E; Matson, David O; Crawford, Sue E; Staat, Mary Allen; Azimi, Parvin; Bennett, Berkeley L; Piedra, Pedro A; Conner, Margaret E

2007-01-01

Background Antigenemia is commonly detected in rotavirus-infected children. Although rotavirus RNA has been detected in serum, definitive proof of rotavirus viremia has not been shown. We aimed to analyze a defined patient population to determine if infectious virus could be detected in sera from children with rotavirus antigenemia. Methods and Findings Serum samples obtained upon hospitalization from children with gastroenteritis (57 stool rotavirus-positive and 41 rotavirus-negative), children with diagnosed bronchiolitis of known (n = 58) or unknown (n = 17) viral etiology, children with noninfectious, nonchronic conditions (n = 17), and healthy adults (n = 28) were tested for rotavirus antigen by enzyme immunoassay (EIA). Results of serum antigen testing were assessed for association with clinical and immunological attributes of the children. Rotavirus antigenemia was detected in 90% (51/57) of children with rotavirus-positive stools, in 89% (8/9) of children without diarrhea but with rotavirus-positive stools, in 12% (2/17) of children with bronchiolitis of unknown etiology without gastroenteritis, and in 12% (5/41) of children with gastroenteritis but with rotavirus-negative stools. Antigenemia was not detected in sera from children with noninfectious nonchronic conditions, children with bronchiolitis of known etiology and no gastroenteritis, or healthy adults. Neither age nor timing of serum collection within eight days after onset of gastroenteritis significantly affected levels of antigenemia, and there was no correlation between antigenemia and viral genotype. However, there was a negative correlation between serum rotavirus antigen and acute rotavirus-specific serum IgA (r = −0.44, p = 0.025) and IgG (r = −0.40, p = 0.01) titers. We examined 11 antigen-positive and nine antigen-negative sera for infectious virus after three blind serial passages in HT-29 cells using immunofluorescence staining for rotavirus structural and nonstructural proteins

Efficacy and immunogenicity of two or three dose rotavirus-vaccine regimen in South African children over two consecutive rotavirus-seasons: a randomized, double-blind, placebo-controlled trial.

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Madhi, S A; Kirsten, M; Louw, C; Bos, P; Aspinall, S; Bouckenooghe, A; Neuzil, K M; Steele, A D

2012-04-27

Human rotavirus vaccine (HRV; i.e., Rotarix) reduced the incidence of severe rotavirus gastroenteritis (RVGE) by 77% (95% Confidence interval: 56-88%) during the first year of life in South Africa. Persistence of HRV-derived protection against RVGE during subsequent rotavirus seasons, although evident in industrialized settings, remains to be established in African settings. This study reports on the efficacy of HRV against severe RVGE over two consecutive rotavirus seasons in South African children. A prospective, double-blind, placebo controlled multi-centered trial in South Africa and Malawi randomly assigned infants in a 1:1:1 ratio to receive either two (10 and 14 weeks; HRV_2D) or three (6, 10 and 14 weeks; HRV_3D) doses of HRV or placebo. The primary analysis involved pooling of HRV_2D and HRV_3D arms. Episodes of gastroenteritis caused by wild-type rotavirus were identified through active follow-up surveillance and graded by the Vesikari scale. 1339 infants (447 in the HRV_2D group, 447 in the HRV_3D group and 445 in the placebo group) were enrolled in Year 2 of the study, including 1035 (77.3%) who were followed up over two consecutive rotavirus seasons (i.e., Cohort 2 subjects). Rotarix was associated with ongoing protection against severe RVGE, preventing 2.5 episodes per 100 vaccinated children over two consecutive rotavirus seasons; vaccine efficacy: 59% (95% Confidence interval: 1-83%). An exploratory analysis indicated better immunogenicity (among Cohort 1 subjects) and a higher point-efficacy estimate over two seasons in the HRV_3D compared to HRV_2D arms of the study in Cohort 2 subjects. Rotarix is associated with significant reductions in severe gastroenteritis episodes through 2 years of life among South African children. Further research is needed to determine the optimal dosing schedule of Rotarix in providing long-term protection against rotavirus illness in African children. Copyright © 2011 Elsevier Ltd. All rights reserved.

Interactions between tungsten carbide (WC) particulates and metal matrix in WC-reinforced composites

International Nuclear Information System (INIS)

Lou, D.; Hellman, J.; Luhulima, D.; Liimatainen, J.; Lindroos, V.K.

2003-01-01

A variety of experimental techniques have been used to investigate the interactions between tungsten carbide (WC-Co 88/12) particulates and the matrix in some new wear resistant cobalt-based superalloy and steel matrix composites produced by hot isostatic pressing. The results show that the chemical composition of the matrix has a strong influence on the interface reaction between WC and matrix and the structural stability of the WC particulates in the composite. Some characteristics of the interaction between matrix and reinforcement are explained by the calculation of diffusion kinetics. The three-body abrasion wear resistance of the composites has been examined based on the ASTM G65-91 standard procedure. The wear behavior of the best composites of this study shows great potential for wear protection applications

Pathogenesis of Rotavirus Infection

NARCIS (Netherlands)

J.A. Boshuizen

2005-01-01

textabstractRotaviruses comprise a genus within the family of the Reoviridae and are recognized as the single most significant cause of severe gastroenteritis, malnutrition and diarrhea in young children. Each year rotavirus causes the death of about 440.000 children <5 years of age (313). The

A gastrointestinal rotavirus infection mouse model for immune modulation studies

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van Amerongen Geert

2011-03-01

Full Text Available Abstract Background Rotaviruses are the single most important cause of severe diarrhea in young children worldwide. The current study was conducted to assess whether colostrum containing rotavirus-specific antibodies (Gastrogard-R® could protect against rotavirus infection. In addition, this illness model was used to study modulatory effects of intervention on several immune parameters after re-infection. Methods BALB/c mice were treated by gavage once daily with Gastrogard-R® from the age of 4 to 10 days, and were inoculated with rhesus rotavirus (RRV at 7 days of age. A secondary inoculation with epizootic-diarrhea infant-mouse (EDIM virus was administered at 17 days of age. Disease symptoms were scored daily and viral shedding was measured in fecal samples during the post-inoculation periods. Rotavirus-specific IgM, IgG and IgG subclasses in serum, T cell proliferation and rotavirus-specific delayed-type hypersensitivity (DTH responses were also measured. Results Primary inoculation with RRV induced a mild but consistent level of diarrhea during 3-4 days post-inoculation. All mice receiving Gastrogard-R® were 100% protected against rotavirus-induced diarrhea. Mice receiving both RRV and EDIM inoculation had a lower faecal-viral load following EDIM inoculation then mice receiving EDIM alone or Gastrogard-R®. Mice receiving Gastrogard-R® however displayed an enhanced rotavirus-specific T-cell proliferation whereas rotavirus-specific antibody subtypes were not affected. Conclusions Preventing RRV-induced diarrhea by Gastrogard-R® early in life showed a diminished protection against EDIM re-infection, but a rotavirus-specific immune response was developed including both B cell and T cell responses. In general, this intervention model can be used for studying clinical symptoms as well as the immune responses required for protection against viral re-infection.

Prevalence and factors associated with rotavirus infection among children admitted with acute diarrhea in Uganda

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Mworozi Edison A

2010-09-01

Full Text Available Abstract Background Rotavirus remains the commonest cause of severe dehydrating diarrhea among children worldwide. Children in developing countries die more because of several factors including poorer access to hydration therapy and greater prevalence of malnutrition. Hitherto, the magnitude of rotavirus disease in Uganda has remained unknown. This study was therefore done to determine the prevalence and factors associated with rotavirus infection among children aged 3-59 months admitted with acute diarrhea to paediatric emergency ward of Mulago Hospital, Uganda Methods Three hundred and ninety children, aged between 3-59 months with acute diarrhoea were recruited. The clinical history, socio-demographic characteristics, physical examination findings and laboratory investigations were recorded. Stool samples were tested for rotavirus antigens using the DAKO IDEIA rotavirus EIA detection kit. Results The prevalence of rotavirus infection was 45.4%. On multivariate analysis rotavirus was significantly associated with a higher education (above secondary level of the mother [OR 1.8; 95% CI 1.1-2.7]; dehydration [OR 1.8; 95% CI 1.1-3.0] and breastfeeding [OR 2.6; 95% CI 1.4-4.0]. Although age was significantly associated with rotavirus on bivariate analysis; this association disappeared on multivariate analysis. No significant association was found between rotavirus infection and nutritional status, HIV status and attendance of day care or school. Conclusions Rotavirus infection is highly prevalent among children with acute diarrhoea admitted to Mulago Hospital in Uganda.

Recombinant monovalent llama-derived antibody fragments (VHH) to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea.

Science.gov (United States)

Vega, Celina G; Bok, Marina; Vlasova, Anastasia N; Chattha, Kuldeep S; Gómez-Sebastián, Silvia; Nuñez, Carmen; Alvarado, Carmen; Lasa, Rodrigo; Escribano, José M; Garaicoechea, Lorena L; Fernandez, Fernando; Bok, Karin; Wigdorovitz, Andrés; Saif, Linda J; Parreño, Viviana

2013-01-01

Group A Rotavirus (RVA) is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs) against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH) to protect against human rotavirus in gnotobiotic (Gn) piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256) for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

Recombinant monovalent llama-derived antibody fragments (VHH to rotavirus VP6 protect neonatal gnotobiotic piglets against human rotavirus-induced diarrhea.

Directory of Open Access Journals (Sweden)

Celina G Vega

Full Text Available Group A Rotavirus (RVA is the leading cause of severe diarrhea in children. The aims of the present study were to determine the neutralizing activity of VP6-specific llama-derived single domain nanoantibodies (VHH nanoAbs against different RVA strains in vitro and to evaluate the ability of G6P[1] VP6-specific llama-derived single domain nanoantibodies (VHH to protect against human rotavirus in gnotobiotic (Gn piglets experimentally inoculated with virulent Wa G1P[8] rotavirus. Supplementation of the daily milk diet with 3B2 VHH clone produced using a baculovirus vector expression system (final ELISA antibody -Ab- titer of 4096; virus neutralization -VN- titer of 256 for 9 days conferred full protection against rotavirus associated diarrhea and significantly reduced virus shedding. The administration of comparable levels of porcine IgG Abs only protected 4 out of 6 of the animals from human RVA diarrhea but significantly reduced virus shedding. In contrast, G6P[1]-VP6 rotavirus-specific IgY Abs purified from eggs of hyperimmunized hens failed to protect piglets against human RVA-induced diarrhea or virus shedding when administering similar quantities of Abs. The oral administration of VHH nanoAb neither interfered with the host's isotype profiles of the Ab secreting cell responses to rotavirus, nor induced detectable host Ab responses to the treatment in serum or intestinal contents. This study shows that the oral administration of rotavirus VP6-VHH nanoAb is a broadly reactive and effective treatment against rotavirus-induced diarrhea in neonatal pigs. Our findings highlight the potential value of a broad neutralizing VP6-specific VHH nanoAb as a treatment that can complement or be used as an alternative to the current strain-specific RVA vaccines. Nanobodies could also be scaled-up to develop pediatric medication or functional food like infant milk formulas that might help treat RVA diarrhea.

Modulation of rotavirus severe gastroenteritis by the combination of probiotics and prebiotics.

Science.gov (United States)

Gonzalez-Ochoa, Guadalupe; Flores-Mendoza, Lilian K; Icedo-Garcia, Ramona; Gomez-Flores, Ricardo; Tamez-Guerra, Patricia

2017-09-01

Annual mortality rates due to infectious diarrhea are about 2.2 million; children are the most vulnerable age group to severe gastroenteritis, representing group A rotaviruses as the main cause of disease. One of the main factors of rotavirus pathogenesis is the NSP4 protein, which has been characterized as a viral toxin involved in triggering several cellular responses leading to diarrhea. Furthermore, the rotavirus protein NSP1 has been associated with interferon production inhibition by inducing the degradation of interferon regulatory factors IRF3, IRF5, and IRF7. On the other hand, probiotics such as Bifidobacterium and Lactobacillus species in combination with prebiotics such as inulin, HMO, scGOS, lcFOS have been associated with improved generalized antiviral response and anti-rotavirus effect by the reduction of rotavirus infectivity and viral shedding, decreased expression of NSP4 and increased levels of specific anti-rotavirus IgAs. Moreover, these probiotics and prebiotics have been related to shorter duration and severity of rotavirus diarrhea, to the prevention of infection and reduced incidence of reinfections. In this review we will discuss in detail about the rotavirus pathogenesis and immunity, and how probiotics such as Lactobacillus and Bifidobacterium species in combination with prebiotics have been associated with the prevention or modulation of rotavirus severe gastroenteritis.

Heterogeneity of Rotavirus Vaccine Efficacy Among Infants in Developing Countries.

Science.gov (United States)

Gruber, Joann F; Hille, Darcy A; Liu, G Frank; Kaplan, Susan S; Nelson, Micki; Goveia, Michelle G; Mast, T Christopher

2017-01-01

Rotavirus is the leading cause of severe diarrhea worldwide in young children. Although rotavirus vaccine efficacy is high in developed countries, efficacy is lower in developing countries. Here, we investigated heterogeneity of rotavirus vaccine efficacy by infant characteristics in developing countries. An exploratory, post hoc analysis was conducted using randomized controlled trial data of the pentavalent rotavirus vaccine (RV5) conducted in Africa and Asia (NCT00362648). Infants received either 3 doses of vaccine/placebo and were followed for up to 2 years. Within subgroups, vaccine efficacies and 95% confidence intervals (CIs) against rotavirus gastroenteritis (RVGE) were estimated using Poisson regression. We assessed heterogeneity of efficacy by age at first dose, gender, breastfeeding status and nutrition status. African children receiving the first dose at efficacy (23.7%; 95% CI: -8.2%-46.3%) than those vaccinated at ≥8 weeks (59.1%; 95% CI: 34.0%-74.6%). Marginally statistically significant differences were observed by age at first dose, gender and underweight status in Ghana and gender in Asian countries. Heterogeneity of efficacy was observed for age at first dose in African countries. This was an exploratory analysis; additional studies are needed to validate these results.

Rotavirus vaccine effectiveness in preventing hospitalizations due to gastroenteritis: a descriptive epidemiological study from Germany.

Science.gov (United States)

Pietsch, C; Liebert, U G

2018-04-10

Rotavirus infections are common causes of infant hospitalization. The present study examined the effectiveness of anti-rotavirus vaccination in preventing rotavirus-related hospitalizations in Germany, following its state and nationwide introductions in 2008 and 2013, respectively. During 15 consecutive seasons 9557 stool samples of hospitalized children of 5 years and younger with acute gastroenteritis were screened for rotavirus A. Rotavirus G and P genotypes were assessed after vaccine introduction. Vaccine effectiveness was determined by comparison of rotavirus incidence in pre-vaccine and post-vaccine cohorts. The herd effect was calculated as the difference between the observed reduction of rotavirus-related hospitalizations and the expected direct vaccine effect. The number of rotavirus-related hospitalizations declined after vaccine introduction. Approximately 26% (503/1955) of prevented cases could be attributed to the herd effect. Human rotaviruses of genotypes G3P[8], G1P[8], G9P[8], G4P[8], G2P[4] and G12P[8] were most frequent. Uncommon genotypes remained rare. The direct, indirect, total and overall vaccine effectiveness was 86% (95% confidence interval (CI) 83.2-89.1%), 48% (95% CI 42.8-52.6%), 93% (95% CI 91.3-94.3%) and 69% (95% CI 66.5-72.0%), respectively. There was no significant difference in vaccine-type or in genotype-specific vaccine effectiveness. Anti-rotavirus vaccination efficiently reduced rotavirus-related hospitalizations in Germany in the past decade. The vaccines analysed in this article provide a broadly heterologous and long-lasting protection. The herd effect substantially contributed to the observed drop in the number of incidences of severe rotavirus infections. Presumably, constant high vaccine coverage will lead to a continued upward trend in the overall vaccine efficiency. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Impact of routine rotavirus vaccination on all-cause and rotavirus hospitalizations during the first four years following vaccine introduction in Rwanda.

Science.gov (United States)

Sibomana, Hassan; Rugambwa, Celse; Mwenda, Jason M; Sayinzoga, Felix; Iraguha, Gisele; Uwimana, Jeanine; Parashar, Umesh D; Tate, Jacqueline E

2018-05-10

Rwanda introduced pentavalent rotavirus vaccine into its national immunization program in 2012. To determine the long-term impact of rotavirus vaccine on disease burden in a high burden setting, we examined trends in rotavirus and all-cause diarrhea hospitalizations in the first four years following rotavirus vaccine introduction. We used data from an active surveillance system, from a review of pediatric ward registries, and from the Health Management Information System to describe trends in rotavirus and all-cause diarrhea hospitalizations from January 2009 through December 2016. Percent reductions were calculated to compare the number of all-cause and rotavirus diarrhea hospitalizations pre- and post-rotavirus vaccine introduction. The proportion of diarrhea hospitalizations due to rotavirus declined by 25-44% among all children introduction to 12-13% post-vaccine introduction. In the national hospital discharge data, substantial decreases were observed in all-cause diarrhea hospitalizations among children introduction era. Published by Elsevier Ltd.

Sunlight-induced inactivation of human Wa and porcine OSU rotaviruses in the presence of exogenous photosensitizers

KAUST Repository

Romero-Maraccini, Ofelia C.

2013-10-01

Human rotavirus Wa and porcine rotavirus OSU solutions were irradiated with simulated solar UV and visible light in the presence of different photosensitizers dissolved in buffered solutions. For human rotavirus, the exogenous effects were greater than the endogenous effects under irradiation with full spectrum and UVA and visible light at 25 C. For porcine rotavirus, the exogenous effects with UVA and visible light irradiation were only observed at high temperatures, >40 C. The results from dark experiments conducted at different temperatures suggest that porcine rotavirus has higher thermostability than human rotavirus. Concentrations of 3′-MAP excited triplet states of 1.8 fM and above resulted in significant human rotavirus inactivation. The measured excited triplet state concentrations of ≤0.45 fM produced by UVA and visible light irradiation of natural dissolved organic matter solutions were likely not directly responsible for rotavirus inactivation. Instead, the linear correlation for human rotavirus inactivation rate constant (kobs) with the phenol degradation rate constant (kexp) found in both 1 mM NaHCO3 and 1 mM phosphate-buffered solutions suggested that OH radical was a major reactive species for the exogenous inactivation of rotaviruses. Linear correlations between rotavirus kobs and specific UV254 nm absorbance of two river-dissolved organic matter and two effluent organic matter isolates indicated that organic matter aromaticity may help predict formation of radicals responsible for rotavirus inactivation. The results from this study also suggested that the differences in rotavirus strains should be considered when predicting solar inactivation of rotavirus in sunlit surface waters. © 2013 American Chemical Society.

Prevalence of Rotavirus in shellfish from Southern Kerala

Directory of Open Access Journals (Sweden)

Vysakh Mohan

2014-10-01

Full Text Available Aim: To study the prevalence of Rotavirus in shellfish from Southern Kerala. Materials and Methods: The shellfish samples after processing was concentrated using proteinase K. RNA was isolated from the concentrated samples using phenol chloroform method. Rota viral RNA was detected using reverse transcriptionpolymerase chain reaction. Results: A low prevalence of 2.5% (5/200 was obtained during the study. Rotavirus was detected in 2 out of 60 brown mussels (3.33%, 2 out of 70 yellow clams (2.86% and 1 out of 70 black clams (1.43%. Conclusion: Low prevalence of Rotavirus was obtained in our study. A more extensive study need to be conducted to estimate the prevalence of enteric virus in shellfish.

A systematic review of genetic diversity of human rotavirus circulating in South Korea.

Science.gov (United States)

Than, Van Thai; Jeong, Sunyoung; Kim, Wonyong

2014-12-01

Rotavirus infections continue to be the leading cause of severe diarrhea in young Korean children. Rotavirus data acquired from uninterrupted surveillance studies between 1989 and 2009 in South Korea were analyzed to better understand the genetic diversity and evolution. The relationship between rotaviruses and the currently licensed rotavirus vaccine viruses was also examined. The most prevalent rotavirus strains, with genotype G1P[8], followed by G3P[8], G4P[6], and G2P[4], accounted for approximately 76.7% of the total identified strains, and more recently, rotavirus G9P[8] has significance increased to be the fifth most common genotype. Phylogenetic analyses underscored the heterogeneity between viral populations within each genotype, with different lineages and sub-lineages. Although the currently licensed rotavirus vaccines are effective, safe, and economical, additional data from rotavirus monitoring is necessary to evaluate the efficacy of these vaccines for their sustained use in South Korea. The present study provides comprehensive and up-to-date information regarding the epidemiology, genetic diversity, and evolution of the circulating rotaviruses in South Korea. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.

Rotavirus Immunization in Africa: A Perspective Re-visited

African Journals Online (AJOL)

trials in developed countries, the history of rotavirus vaccine in Africa has not been good. The earlier rotavirus vaccine candidates, based on bovine rotavirus strains, were ... trials in Peru and Brazil [19,20]. Other more obvious reasons may include vaccine-related issues (such as the antigenic make-up of the bovine rotavirus ...

Rapid strategy for screening by pyrosequencing of influenza virus reassortants--candidates for live attenuated vaccines.

Science.gov (United States)

Shcherbik, Svetlana V; Pearce, Nicholas C; Levine, Marnie L; Klimov, Alexander I; Villanueva, Julie M; Bousse, Tatiana L

2014-01-01

Live attenuated influenza vaccine viruses (LAIVs) can be generated by classical reassortment of gene segments between a cold adapted, temperature sensitive and attenuated Master Donor Virus (MDV) and a seasonal wild-type (wt) virus. The vaccine candidates contain hemagglutinin (HA) and neuraminidase (NA) genes derived from the circulating wt viruses and the remaining six genes derived from the MDV strains. Rapid, efficient selection of the viruses with 6∶2 genome compositions from the large number of genetically different viruses generated during reassortment is essential for the biannual production schedule of vaccine viruses. This manuscript describes a new approach for the genotypic analysis of LAIV reassortant virus clones based on pyrosequencing. LAIV candidate viruses were created by classical reassortment of seasonal influenza A (H3N2) (A/Victoria/361/2011, A/Ohio/02/2012, A/Texas/50/2012) or influenza A (H7N9) (A/Anhui/1/2013) wt viruses with the MDV A/Leningrad/134/17/57(H2N2). Using strain-specific pyrosequencing assays, mixed gene variations were detected in the allantoic progenies during the cloning procedure. The pyrosequencing analysis also allowed for estimation of the relative abundance of segment variants in mixed populations. This semi-quantitative approach was used for selecting specific clones for the subsequent cloning procedures. The present study demonstrates that pyrosequencing analysis is a useful technique for rapid and reliable genotyping of reassortants and intermediate clones during the preparation of LAIV candidates, and can expedite the selection of vaccine virus candidates.

Rapid strategy for screening by pyrosequencing of influenza virus reassortants--candidates for live attenuated vaccines.

Directory of Open Access Journals (Sweden)

Svetlana V Shcherbik

Full Text Available BACKGROUND: Live attenuated influenza vaccine viruses (LAIVs can be generated by classical reassortment of gene segments between a cold adapted, temperature sensitive and attenuated Master Donor Virus (MDV and a seasonal wild-type (wt virus. The vaccine candidates contain hemagglutinin (HA and neuraminidase (NA genes derived from the circulating wt viruses and the remaining six genes derived from the MDV strains. Rapid, efficient selection of the viruses with 6∶2 genome compositions from the large number of genetically different viruses generated during reassortment is essential for the biannual production schedule of vaccine viruses. METHODOLOGY/PRINCIPAL FINDINGS: This manuscript describes a new approach for the genotypic analysis of LAIV reassortant virus clones based on pyrosequencing. LAIV candidate viruses were created by classical reassortment of seasonal influenza A (H3N2 (A/Victoria/361/2011, A/Ohio/02/2012, A/Texas/50/2012 or influenza A (H7N9 (A/Anhui/1/2013 wt viruses with the MDV A/Leningrad/134/17/57(H2N2. Using strain-specific pyrosequencing assays, mixed gene variations were detected in the allantoic progenies during the cloning procedure. The pyrosequencing analysis also allowed for estimation of the relative abundance of segment variants in mixed populations. This semi-quantitative approach was used for selecting specific clones for the subsequent cloning procedures. CONCLUSIONS/SIGNIFICANCE: The present study demonstrates that pyrosequencing analysis is a useful technique for rapid and reliable genotyping of reassortants and intermediate clones during the preparation of LAIV candidates, and can expedite the selection of vaccine virus candidates.

Zoonotic Transmission of Rotavirus in Denmark; a Case Report

DEFF Research Database (Denmark)

Midgley, Sofie; Gram, N.; Hjulsager, Charlotte Kristiane

Rotavirus type A infection is a common cause of hospitalisation of children. However, in our laboratory almost 30% of rotavirus positive samples are from adults. Due to this an epidemiological study into the riskfactors for rotavirus infection in adults was set up. All identified rotavirus positive...... adults are sent a questionnaire to identify potential risk factors. Rotavirus type A infection can also occur in a range of animals, including domestic dogs, cats, cattle, horses, and birds. There is some data suggesting direct transmission between animals and humans. Rotavirus typing is carried out...... in Denmark as part of the EuroRotaNet vaccine study. Samples positive for rotavirus are type...

Milk Oligosaccharides Inhibit Human Rotavirus Infectivity in MA104 Cells.

Science.gov (United States)

Laucirica, Daniel R; Triantis, Vassilis; Schoemaker, Ruud; Estes, Mary K; Ramani, Sasirekha

2017-09-01

Background: Oligosaccharides in milk act as soluble decoy receptors and prevent pathogen adhesion to the infant gut. Milk oligosaccharides reduce infectivity of a porcine rotavirus strain; however, the effects on human rotaviruses are less well understood. Objective: In this study, we determined the effect of specific and abundant milk oligosaccharides on the infectivity of 2 globally dominant human rotavirus strains. Methods: Four milk oligosaccharides-2'-fucosyllactose (2'FL), 3'-sialyllactose (3'SL), 6'-sialyllactose (6'SL), and galacto-oligosaccharides-were tested for their effects on the infectivity of human rotaviruses G1P[8] and G2P[4] through fluorescent focus assays on African green monkey kidney epithelial cells (MA104 cells). Oligosaccharides were added at different time points in the infectivity assays. Infections in the absence of oligosaccharides served as controls. Results: When compared with infections in the absence of glycans, all oligosaccharides substantially reduced the infectivity of both human rotavirus strains in vitro; however, virus strain-specific differences in effects were observed. Compared with control infections, the maximum reduction in G1P[8] infectivity was seen with 2'FL when added after the onset of infection (62% reduction, P rotaviruses in MA104 cells, primarily through an effect on the virus. Although breastfed infants are directly protected, the addition of specific oligosaccharides to infant formula may confer these benefits to formula-fed infants. © 2017 American Society for Nutrition.

One Family's Struggles with Rotavirus

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Full Text Available ... getvaxed about GETVAXED print ads go to GETVAXED.ORG cme Immunizations Rotavirus One family's struggles with rotavirus ... free-of-charge. Branded videos contain the "PKIDs.ORG" end slate; unbranded videos are provided for organizations ...

One Family's Struggles with Rotavirus

Medline Plus

Full Text Available ... GETVAXED print ads go to GETVAXED.ORG cme Immunizations Rotavirus One family's struggles with rotavirus We provide ... not possible without a visit to your doctor. Immunizations stop disease from spreading. Check with your family ...

The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

OpenAIRE

Renström Lena HM; Isaksson Mats; Berg Mikael; Zohari Siamak; Widén Frederik; Metreveli Giorgi; Bálint Ádám; Wallgren Per; Belák Sándor; Segall Thomas; Kiss István

2009-01-01

Abstract The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority o...

Importance of rotavirus as a cause of gastroenteritis in Jordan: a hospital based study.

Science.gov (United States)

Khuri-Bulos, Najwa; Al Khatib, Mohammad

2006-01-01

Rotavirus is recognized to be a very important cause of GE in younger children in both developed as well as developing countries, but causes most of the mortality and morbidity in the latter. The recent introduction of a rotavirus vaccine in some parts of the world makes it necessary for us to determine the impact of this organism in our population with the aim of determining the need for the vaccine. In order to determine this, a study was conducted at the JUH and 3 other private hospitals. At the JUH, 64/256 (25%) of children with GE had rotavirus in 1995. The proportions of cases attributed to rotavirus in the other 3 y were 70/199 (35.2%), 69/279 (24.7%) and 76/294 (25.8%) for 2002, 2003 and 2004, respectively. The cumulative proportion of cases attributable to rotavirus gastroenteritis in all the y was 27.14%. With regard to the 3 private hospitals, rotavirus accounted for 38/225 (16.9%), 140/664 (21%) and 668/1496 (44.6%) at the Khalidy, Jordan and Islamic hospitals, respectively. It is concluded that rotavirus is a significant cause of GE in Jordanian children regardless of their social background, and attempt at controlling this infection may be warranted.

Sampling and analysis of the inactive waste tanks TH-2, WC-1, and WC-15

International Nuclear Information System (INIS)

Autrey, J.W.; Keller, J.M.; Griest, W.H.; Botts, J.L.; Schenley, R.L.; Sipe, M.A.

1992-02-01

Thirty-eight inactive liquid low-level radioactive waste tanks are currently managed by the Environmental Restoration Program of Oak Ridge National Laboratory. The contents of these tanks are to be characterized in preparation for future corrective actions and remediation activities as part of compliance with the pending Federal Facility Agreement for the Oak Ridge Reservation. Twenty-nine of these tanks were sampled and analyzed in 1989. Three of the tanks (TH-2, WC-1, and WC-15) were not accessible from the surface and thus were not sampled until 1990. This report presents the sampling and analytical results of that campaign. All three tanks in this report had negligible regulatory organic compounds in the samples that were collected. There were no US Environmental Protection Agency (EPA) Target Compound List (TCL) constituents for volatile organics detected in any of the aqueous samples. The only semivolatile organics detected were 2-chlorophenol (52 μg/L) in tank TH-2 and dichloroethane (14--15 μg/L) and diethyl either (15--17 μg/L) in tank WC-15. A thin oil layer was discovered floating on top of the aqueous contents in tank WC-15. The analysis of the oil layer detected no volatile organics and showed only one EPA TCL constituent, di-n-butylphthalate, at 1900 μg/L. Low levels of Resource Conservation and Recovery Act (RCRA) metals were observed in the samples from tank TH-2, but only the mercury level exceeded the RCRA limit. Samples from tank WC-1 had elevated levels of the RCRA metals barium, chromium, and lead. There were also finely suspended particles in one of the samples from tank WC-1, which was filtered and analyzed separately. This solid fines have levels of transuranium elements 238 Pu and 241 Am high enough to classified as transuranic waste

Rotavirus vaccination in Europe: drivers and barriers.

Science.gov (United States)

Parez, N; Giaquinto, C; Du Roure, C; Martinon-Torres, F; Spoulou, V; Van Damme, P; Vesikari, T

2014-05-01

Rotavirus gastroenteritis is a vaccine-preventable disease that confers a high medical and economic burden in more developed countries and can be fatal in less developed countries. Two vaccines with high efficacy and good safety profiles were approved and made available in Europe in 2006. We present an overview of the status of rotavirus vaccination in Europe. We discuss the drivers (including high effectiveness and effect of universal rotavirus vaccination) and barriers (including low awareness of disease burden, perception of unfavourable cost-effectiveness, and potential safety concerns) to the implementation of universal rotavirus vaccination in Europe. By February, 2014, national universal rotavirus vaccination had been implemented in Belgium, Luxembourg, Austria, Finland, Greece, Luxembourg, Norway, and the UK. Four other German states have issued recommendations and reimbursement is provided by sickness funds. Other countries were at various stages of recommending or implementing universal rotavirus vaccination. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reassortment and evolution of current human influenza A and B viruses.

Science.gov (United States)

Xu, Xiyan; Lindstrom, Stephen E; Shaw, Michael W; Smith, Catherine B; Hall, Henrietta E; Mungall, Bruce A; Subbarao, Kanta; Cox, Nancy J; Klimov, Alexander

2004-07-01

During the 2001-2002 influenza season, human influenza A (H1N2) reassortant viruses were detected globally. The hemagglutinin (HA) of these H1N2 viruses was similar to that of the A/New Caledonia/20/99 (H1N1) vaccine strain both antigenically and genetically, while their neuraminidase (NA) was antigenically and genetically related to that of recent human influenza H3N2 reference viruses such as A/Moscow/10/99. All six internal genes of the H1N2 reassortants originated from an H3N2 virus. After being detected only in eastern Asia during the past 10 years, Influenza B/Victoria/2/87 lineage viruses reappeared in many countries outside of Asia in 2001. Additionally, reassortant influenza B viruses possessing an HA similar to that of B/Shandong/7/97, a recent B/Victoria/2/87 lineage reference strain, and an NA closely related to that of B/Sichuan/379/99, a recent B/Yamagata/16/88 lineage reference strain, were isolated globally and became the predominant influenza B epidemic strain. The current influenza vaccine is expected to provide good protection against H1N2 viruses because it contains A/New Caledonia/20/99 (H1N1) and A/Panama/2007/99 (H3N2) like viruses whose H1 HA or N2 NA are antigenically similar to those of recent circulating H1N2 viruses. On the other hand, widespread circulation of influenza B Victoria lineage viruses required inclusion of a strain from this lineage in influenza vaccines for the 2002-2003 season.

Efficacy of the pentavalent rotavirus vaccine, RotaTeq®, in Finnish infants up to 3 years of age: the Finnish Extension Study.

Science.gov (United States)

Vesikari, Timo; Karvonen, Aino; Ferrante, Shannon Allen; Ciarlet, Max

2010-11-01

Rotavirus Efficacy and Safety Trial (REST) enrolled nearly 70,000 infants, of whom more than 23,000 were from Finland. REST determined the efficacy of the pentavalent rotavirus vaccine (RV5) against rotavirus-related hospitalisations and emergency department (ED) visits in the first year after vaccination. Finnish infants initially in REST transitioned into the Finnish Extension Study (FES), where they were followed for rotavirus-related hospitalisations and ED visits through their second year of life and beyond. FES identified 150 (31%) additional rotavirus gastroenteritis (RVGE) cases beyond those identified in REST in the Finnish participants. Overall, RV5 reduced RVGE hospitalisations and ED visits, regardless of the rotavirus serotype, by 93.8% (95% confidence interval [CI]: 90.8-95.9%) for up to 3.1 years following the last vaccine dose. Vaccine efficacy against combined hospitalisations and ED visits between ages 4 months to 11 months, 12 months to 23 months, and 24 months to 35 months was 93.9% (95% CI: 89.1-96.9%), 94.4% (95% CI: 90.2-97.0%), and 85.9% (95% CI: 51.6-97.2%), respectively. The reduction of hospitalisations and ED visits due to any acute gastroenteritis, rotavirus or not, was 62.4% (95% CI: 57.6-66.6%) over the entire follow-up period. The results from FES confirm that RV5 induces high and sustained protection against rotavirus-related hospitalisations and ED visits, and has a very substantial impact on all gastroenteritis-related hospitalisations and ED visits into the third year of life in Finnish children.

Incidence and cost of rotavirus hospitalizations in Denmark

DEFF Research Database (Denmark)

Fischer, Thea Kølsen; Nielsen, Nete Munk; Wohlfahrt, Jan

2007-01-01

In anticipation of licensure and introduction of rotavirus vaccine into the western market, we used modeling of national hospital registry data to determine the incidence and direct medical costs of annual rotavirus-associated admissions over >11 years in Denmark. Diarrhea-associated hospitalizat......In anticipation of licensure and introduction of rotavirus vaccine into the western market, we used modeling of national hospital registry data to determine the incidence and direct medical costs of annual rotavirus-associated admissions over >11 years in Denmark. Diarrhea......-associated hospitalizations coded as nonspecified viral or presumed infectious have demonstrated a marked winter peak similar to that of rotavirus-associated hospitalizations, which suggests that the registered rotavirus-coded admissions are grossly underestimated. We therefore obtained more realistic estimates by 2...... different models, which indicated 2.4 and 2.5 (for children rotavirus-associated admissions per 1,000 children per year, respectively. These admissions amount to associated direct medical costs of US $1.7-1.8 million per year. Using 2 simple...

Distribution of rotavirus genotypes associated with acute diarrhoea in Zimbabwean children less than five years old before and after rotavirus vaccine introduction.

Science.gov (United States)

Mukaratirwa, Arnold; Berejena, Chipo; Nziramasanga, Pasipanodya; Ticklay, Ismail; Gonah, Archebald; Nathoo, Kusum; Manangazira, Portia; Mangwanya, Douglas; Marembo, Joan; Mwenda, Jason M; Weldegebriel, Goitom; Seheri, Mapaseka; Tate, Jacqueline E; Yen, Catherine; Parashar, Umesh; Mujuru, Hilda

2018-04-05

Sentinel surveillance for diarrhoea is important to monitor changes in rotavirus epidemiological trends and circulating genotypes among children under 5 years before and after vaccine introduction. The Zimbabwe Ministry of Health and Child Care introduced rotavirus vaccine in national immunization program in May 2014. Active hospital-based surveillance for diarrhoea was conducted at 3 sentinel sites from 2008 to 2016. Children aged less than 5 years, who presented with acute gastroenteritis as a primary illness and who were admitted to a hospital ward or treated at the emergency unit, were enrolled and had a stool specimen collected and tested for rotavirus by enzyme immunoassay (EIA). Genotyping of positive stools was performed using reverse-transcription polymerase chain reaction and genotyping assays. Pre-vaccine introduction, 10% of all positive stool specimens were genotyped and all adequate positive stools were genotyped post-vaccine introduction. During the pre-vaccine period, a total of 6491 acute gastroenteritis stools were collected, of which 3016 (46%) tested positive for rotavirus and 312 (10%) of the rotavirus positive stools were genotyped. During the post-vaccine period, a total of 3750 acute gastroenteritis stools were collected, of which 937 (25%) tested positive for rotavirus and 784 (84%) were genotyped. During the pre-vaccine introduction the most frequent genotype was G9P[8] (21%) followed by G2P[4] (12%), G1P[8] (6%), G2P[6] (5%), G12P[6] (4%), G9P[6] (3%) and G8P[4] (3%). G1P[8] (30%) was most dominant two years after vaccine introduction followed by G9P[6] (20%), G2P[4] (15%), G9P[8] (11%) and G1P[6] (4%). The decline in positivity rate is an indication of early vaccine impact. Diversity of circulating strains underscores the importance of continued monitoring and strain surveillance after vaccine introduction. Copyright © 2018. Published by Elsevier Ltd.

Gene number determination and genetic polymorphism of the gamma delta T cell co-receptor WC1 genes

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Chen Chuang

2012-10-01

Full Text Available Abstract Background WC1 co-receptors belong to the scavenger receptor cysteine-rich (SRCR superfamily and are encoded by a multi-gene family. Expression of particular WC1 genes defines functional subpopulations of WC1+ γδ T cells. We have previously identified partial or complete genomic sequences for thirteen different WC1 genes through annotation of the bovine genome Btau_3.1 build. We also identified two WC1 cDNA sequences from other cattle that did not correspond to sequences in the Btau_3.1 build. Their absence in the Btau_3.1 build may have reflected gaps in the genome assembly or polymorphisms among animals. Since the response of γδ T cells to bacterial challenge is determined by WC1 gene expression, it was critical to understand whether individual cattle or breeds differ in the number of WC1 genes or display polymorphisms. Results Real-time quantitative PCR using DNA from the animal whose genome was sequenced (“Dominette” and sixteen other animals representing ten breeds of cattle, showed that the number of genes coding for WC1 co-receptors is thirteen. The complete coding sequences of those thirteen WC1 genes is presented, including the correction of an error in the WC1-2 gene due to mis-assembly in the Btau_3.1 build. All other cDNA sequences were found to agree with the previous annotation of complete or partial WC1 genes. PCR amplification and sequencing of the most variable N-terminal SRCR domain (domain 1 which has the SRCR “a” pattern of each of the thirteen WC1 genes showed that the sequences are highly conserved among individuals and breeds. Of 160 sequences of domain 1 from three breeds of cattle, no additional sequences beyond the thirteen described WC1 genes were found. Analysis of the complete WC1 cDNA sequences indicated that the thirteen WC1 genes code for three distinct WC1 molecular forms. Conclusion The bovine WC1 multi-gene family is composed of thirteen genes coding for three structural forms whose

Rotavirus and the Vaccine (Drops) to Prevent It

Science.gov (United States)

... Resources Maternal Immunization Resources Related Links Vaccines & Immunizations Rotavirus and the Vaccine (Drops) to Prevent It Language: ... the vaccine. Why should my child get the rotavirus vaccine? The rotavirus vaccine: Protects your child from ...

Unexpectedly high burden of rotavirus gastroenteritis in very young infants

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Reilly Megan

2010-06-01

Full Text Available Abstract Background The highest incidence of rotavirus gastroenteritis has generally been reported in children 6-24 months of age. Young infants are thought to be partially protected by maternal antibodies acquired transplacentally or via breast milk. The purpose of our study was to assess the age distribution of children with confirmed community-acquired rotavirus gastroenteritis presenting to an urban referral hospital. Methods Children presenting to The Children's Hospital of Philadelphia with acute gastroenteritis have been monitored for the presence of rotavirus antigen in the stool by ELISA (followed by genotyping if ELISA-positive since the 1994-95 epidemic season. Results Over the last 12 rotavirus seasons prior to the introduction of the pentavalent rotavirus vaccine in 2006, stool specimens from 1646 patients tested positive for community-acquired rotavirus infection. Gender or age was not recorded in 6 and 5 cases, respectively. Overall, 58% of the cases occurred in boys. G1 was the predominant VP7 serotype, accounting for 72% of cases. The median (IQR age was 11 (5-21 months. A total of 790 (48% cases occurred in children outside the commonly quoted peak age range, with 27% in infants 24 months of age. A total of 220 (13% cases occurred during the first 3 months of life, and the highest number of episodes per month of age [97 (6%] was observed during the second month of life. Conclusions The incidence of community-acquired rotavirus gastroenteritis monitored over 12 seasons in the prevaccine era at a major university hospital was nearly constant for each month of age during the first year of life, revealing an unexpectedly high incidence of symptomatic rotavirus disease in infants

Rotaviruses

Centers for Disease Control (CDC) Podcasts

CDC's Dr. Jon Gentsch discusses rotaviruses, the most important cause of severe gastroenteritis in children less than five years of age. Essentially, all children around the world get the disease during the first few years of life.

Sunlight-induced inactivation of human Wa and porcine OSU rotaviruses in the presence of exogenous photosensitizers

KAUST Repository

Romero-Maraccini, Ofelia C.; Sadik, Nora J.; Rosado-Lausell, Sahid L.; Pugh, Charles R.; Niu, Xi-Zhi; Croue, Jean-Philippe; Nguyen, Thanh Ha

2013-01-01

dark experiments conducted at different temperatures suggest that porcine rotavirus has higher thermostability than human rotavirus. Concentrations of 3′-MAP excited triplet states of 1.8 fM and above resulted in significant human rotavirus inactivation

Surveillance of Rotavirus Diarrhea in Hasan Sadikin Hospital Bandung

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Dwi Prasetyo

2010-12-01

Full Text Available The diarrhea morbidity in Indonesia has increased, however, all the reports had not been done carefully, so that accurate surveillance are essential for improving quality of morbidity data. To determine the prevalence and clinical manifestations of rotavirus diarrhea and to characterize the circulating rotavirus strains, children below 5 years old who were admitted to Hasan Sadikin Hospital, Bandung because of diarrhea, from January 2006 through March 2007 were enrolled in a surveillance study and had stool specimens tested for the presence of rotavirus using enzyme immunoassay (EIA. The strains of rotavirus were determined using reverse transcriptase-polymerase chain reaction (RT-PCR. Rotavirus were detected in 47.8% analyzed samples (87/184, G and P-genotype of rotavirus were G[1] (37.5% and P[6] (53.5%. Most subjects were males (56%, 6–11 months of age (35%. Most common clinical manifestations besides diarrhea were dehydration (72.7% and vomiting (50%. Subjects with positive rotavirus more common had dehydration (72% vs 28% and vomiting (61% vs 39%. In conclusion, vomiting and dehydration are the prominent clinical manifestations of diarrhea with positive rotavirus infection. G1 and P6 are the most common genotype of rotavirus.

CNS complications of rotavirus gastroenteritis

International Nuclear Information System (INIS)

Volosinova, D.

2010-01-01

Rotavirus infection may be accompanied by serious complications, e.g. disabilities central nervous system (CNS). Theory rotavirus penetration across the blood-brain barrier and subsequent rota-associated convulsions by the 2-year case-history of the patient. Rotavirosis minor gastrointestinal symptoms may lead to erroneous diagnosis. (author)

Outbreak of rotavirus gastroenteritis with high mortality, Nicaragua, 2005 Brote de gastroenteritis por rotavirus con alta mortalidad, Nicaragua, 2005

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Juan José Amador

2008-04-01

Full Text Available OBJECTIVES: We investigated a nationwide outbreak of severe rotavirus gastroenteritis in Nicaragua in children under 5 years old, leading to many consultations, hospitalizations, and deaths. We questioned whether a vaccine might have prevented these illnesses and deaths, sought to identify risk factors for death, and developed a clinical profile of children hospitalized with diarrhea. METHODS: We conducted a case-control study to determine whether children who died had access to routine immunizations, a proxy predicting access to a rotavirus vaccine. We identified risk factors for death among children who died in the outbreak compared with surviving age-matched controls with diarrhea. We collected stools, clinical data, and immunization data on children hospitalized for diarrhea to test for rotavirus, develop the profile, and forecast future access to a rotavirus vaccine. RESULTS: The outbreak from February to April 2005 caused 47 470 consultations and 52 deaths. Approximately 80% of cases and controls and 60% of children hospitalized with diarrhea had access to routine immunizations and would likely have had access to a rotavirus vaccine. With a vaccine efficacy of 85%, up to 51% of severe rotavirus cases and up to 68% of deaths could have been prevented if a rotavirus vaccine were available as part of routine child-hood immunizations. Study of 35 case-control pairs indicated that severe illnesses, malnutrition, and care by traditional healers were risk factors for death. Rotavirus was found in 42% of samples from hospitalized children and was associated with severe disease and dehydration. CONCLUSIONS: The impact of the seasonal outbreaks of rotavirus disease could be diminished with a rotavirus vaccine, improvements in oral rehydration programs, and training of traditional healers in the proper management of children with acute diarrhea.OBJETIVOS: Se investigó un brote nacional de gastroenteritis grave por rotavirus en niños menores de 5 a

Severe Rotavirus gastroenteritis in a patient with infant leukemia

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Hatice Uygun

2011-03-01

Full Text Available Rotavirus is the most common cause of severe gastroenteritis in infants and young children. Reports about the clinical relevance of rotavirus in immunocompromised children are rare. We herein presented a case of life-threatening Rotavirus gastroenteritis in an infant with acute myeloblastic leukemia which could be prevented by recently recommended Rotavirus vaccination.

Outstanding challenges for rotavirus vaccine introduction in low-income countries

DEFF Research Database (Denmark)

Ustrup, Marte; Madsen, Lizell B; Bygbjerg, Ib C

2011-01-01

Rotavirus infections are the most common cause of severe diarrhoea in children worldwide. Two internationally licensed rotavirus vaccines have proven to be efficacious in middle and high-income countries and they could potentially be valuable tools for the prevention of rotavirus....... There is also a need for political commitment to prevent rotavirus infections as well as a need for an overall strengthening of the health systems in low-income countries. If these challenges were met, rotavirus vaccination could substantially improve child health and survival from rotavirus...

Acute myositis associated with concurrent infection of rotavirus and norovirus in a 2-year-old girl

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Kei Yamamoto

2015-09-01

Full Text Available Rotavirus and norovirus are common pathogens associated with gastroenteritis in children. Although rotavirus occasionally induces central nervous system disease, only 3 cases with rotavirus-induced acute myositis have been reported in the English literature. We recently treated a female patient with acute myositis associated with gastroenteritis induced by concurrent infection with rotavirus and norovirus. Having suffered from gastroenteritis for 3 days, she suddenly developed myositis affecting her lower extremities with concomitant creatine kinase elevation. Herein, we present our patient and review the previous cases including those reported in the Japanese literature.

Inhibition of rotavirus replication by a non-neutralizing, rotavirus VP6–specific IgA mAb

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Feng, Ningguo; Lawton, Jeffrey A.; Gilbert, Joana; Kuklin, Nelly; Vo, Phuoc; Prasad, B.V. Venkataram; Greenberg, Harry B.

2002-01-01

Rotaviruses are the leading cause of severe diarrheal disease in young children. Intestinal mucosal IgA responses play a critical role in protective immunity against rotavirus reinfection. Rotaviruses consist of three concentric capsid layers surrounding a genome of 11 segments of double-stranded RNA. The outer layer proteins, VP4 and VP7, which are responsible for viral attachment and entry, are targets for protective neutralizing antibodies. However, IgA mAb’s directed against the intermediate capsid protein VP6, which do not neutralize the virus, have also been shown to protect mice from rotavirus infection and clear chronic infection in SCID mice. We investigated whether the anti-VP6 IgA (7D9) mAb could inhibit rotavirus replication inside epithelial cells and found that 7D9 acted at an early stage of infection to neutralize rotavirus following antibody lipofection. Using electron cryomicroscopy, we determined the three-dimensional structure of the virus-antibody complex. The attachment of 7D9 IgA to VP6 introduces a conformational change in the VP6 trimer, rendering the particle transcriptionally incompetent and preventing the elongation of initiated transcripts. Based on these observations, we suggest that anti-VP6 IgA antibodies confers protection in vivo by inhibiting viral transcription at the start of the intracellular phase of the viral replication cycle. PMID:11994409

An evaluation of the Australian Rotavirus Surveillance Program.

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Roberts-Witteveen, April R; Patel, Mahomed S; Roche, Paul W

2008-09-01

The Australian Rotavirus Serotyping Program (ARSP) serotypes rotavirus isolates obtained from stool samples sent from Australian laboratories. In collaboration with ARSP the Australian Government Department of Health and Ageing evaluated the program for its utility and capacity to monitor effectiveness of the rotavirus vaccines recently introduced into the Australian National Immunisation Program. The system was described using ARSP annual reports and staff interviews. The attributes of the system were assessed by adapting standard guidelines for evaluating a surveillance system. Email surveys or face to face interviews were conducted with staff of ARSP, participating laboratories, rotavirus vaccine manufacturing companies and representatives of the Communicable Diseases Network Australia. The ability of the ARSP to monitor changes in rotavirus serotype epidemiology was assessed. ARSP serotypes rotavirus isolates received from participating laboratories at least bi-annually, with results being reported at least as often. Serotype analyses have informed formulation of rotavirus vaccines and contributed to forecasting the extent of outbreaks caused by novel serotypes. The ARSP will be able to monitor changes in rotavirus serotype epidemiology and identify probable vaccination failures. Enhancement of the representativeness and sensitivity of the system are needed for the data to remain useful in the public health context. Methods for transferring data between the program and state and territory health departments need to be developed.

Anticipating rotavirus vaccines: review of epidemiologic studies of rotavirus diarrhea in Argentina En anticipación de una vacuna antirrotavirus: revisión de estudios epidemiológicos sobre la diarrea por rotavirus en la Argentina

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Jorge A. Gómez

1998-02-01

Full Text Available Rotavirus is the most common cause of severe diarrhea in children worldwide, and vaccines currently being field-tested could be available for childhood immunization in several years. To assess the rotavirus disease burden in Argentina and the value of future national surveillance for the disease, we reviewed available data on rotavirus detections reported by published and unpublished studies conducted in nine Argentine cities and by a multicenter study. Data from these studies indicated that rotavirus was detected in 20% of 5 226 specimens (within a range of 6% to 54% for different studies from children hospitalized for diarrhea and in 9% of 6 587 specimens (within a range of 5% to 22% for different studies from children who were outpatients, members of mixed populations (hospitalized patients and outpatients, or survey subjects in community-based studies. The hospital data showed that while rotavirus was detected throughout the year, a peak occurred during the winter months (May­July, when up to half of the children with diarrhea were found positive for rotavirus. Attempted serotyping of 294 rotavirus-positive specimens for G-protein by three laboratories was successful in 230 cases (78%; the resulting data indicated that serotype G1 was the most common (being present in 60% of the successfully serotyped specimens, followed by G2 (in 20%, G4 (in 14%, and G3 (in 5%. Based on national data for Argentina, we estimate that in 1991 there were roughly 84 500 rotavirus-associated outpatient visits (1 for every 8 births and 21 000 hospitalizations averaging 4 days in length (1 for every 31 births, all of which entailed direct medical costs estimated at US$ 27.7 million. These preliminary data show that the rotavirus disease burden in Argentine children is extensive and could be decreased by a safe and effective vaccine. Further surveillance is needed to improve our understanding of the epidemiology and distribution of rotavirus strains in Argentina

Grinding of WC-Co hard-metals

NARCIS (Netherlands)

Hegeman, J.B.J.W.; Hosson, de J.Th.M.; With, de G.

2001-01-01

Morphol. of ground surface of WC-Co cermets with 10 and 20% Co was studied. A deformed and detached surface layer was found on top of the specimens after surface grinding with a diamond wheel. Etching the surface layer revealed WC grains in the subsurface of the machined specimens. Most of these

Rotavirus vaccination within the South African Expanded Programme on Immunisation.

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Seheri, L Mapaseka; Page, Nicola A; Mawela, Mothahadini P B; Mphahlele, M Jeffrey; Steele, A Duncan

2012-09-07

Diarrhoeal diseases are ranked the third major cause of childhood mortality in South African children less than 5 years, where the majority of deaths are among black children. Acute severe dehydrating rotavirus diarrhoea remains an important contributor towards childhood mortality and morbidity and has been well documented in South Africa. As the preventive strategy to control rotavirus diarrhoea, South Africa became the first country in the WHO African Region to adopt the rotavirus vaccine in the national childhood immunisation programme in August 2009. The rotavirus vaccine in use, Rotarix, GSK Biologicals, is given at 6 and 14 weeks of age, along with other vaccines as part of Expanded Programme on Immunisation (EPI). Studies which facilitated the introduction of rotavirus vaccine in South Africa included the burden of rotavirus disease and strain surveillance, economic burden of rotavirus infection and clinical trials to assess the safety and efficacy of vaccine candidates. This paper reviews the epidemiology of rotavirus in South Africa, outlines some of the steps followed to introduce rotavirus vaccine in the EPI, and highlights the early positive impact of vaccination in reducing the rotavirus burden of disease based on the post-marketing surveillance studies at Dr George Mukhari hospital, a sentinel site at University of Limpopo teaching hospital in Pretoria, South Africa, which has conducted rotavirus surveillance for >20 years. Copyright © 2012 Elsevier Ltd. All rights reserved.

Cost-effectiveness of rotavirus vaccination in Albania.

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Ahmeti, Albana; Preza, Iria; Simaku, Artan; Nelaj, Erida; Clark, Andrew David; Felix Garcia, Ana Gabriela; Lara, Carlos; Hoestlandt, Céline; Blau, Julia; Bino, Silvia

2015-05-07

Rotavirus vaccines have been introduced in several European countries but can represent a considerable cost, particularly for countries that do not qualify for any external financial support. This study aimed to evaluate the cost-effectiveness of introducing rotavirus vaccination into Albania's national immunization program and to inform national decision-making by improving national capacity to conduct economic evaluations of new vaccines. The TRIVAC model was used to assess vaccine impact and cost-effectiveness. The model estimated health and economic outcomes attributed to 10 successive vaccinated birth cohorts (2013-2022) from a government and societal perspective. Epidemiological and economic data used in the model were based on national cost studies, and surveillance data, as well as estimates from the scientific literature. Cost-effectiveness was estimated for both the monovalent (RV1) and pentavalent vaccines (RV5). A multivariate scenario analysis (SA) was performed to evaluate the uncertainty around the incremental cost-effectiveness ratios (ICERs). With 3% discounting of costs and health benefits over the period 2013-2022, rotavirus vaccination in Albania could avert 51,172 outpatient visits, 14,200 hospitalizations, 27 deaths, 950 disability-adjusted life-years (DALYs), and gain 801 life-years. When both vaccines were compared to no vaccination, the discounted cost per DALY averted was US$ 2008 for RV1 and US$ 5047 for RV5 from a government perspective. From the societal perspective the values were US$ 517 and US$ 3556, respectively. From both the perspectives, the introduction of rotavirus vaccine to the Albanian immunization schedule is either cost-effective or highly cost-effective for a range of plausible scenarios. In most scenarios, including the base-case scenario, the discounted cost per DALY averted was less than three times the gross domestic product (GDP) per capita. However, rotavirus vaccination was not cost-effective when rotavirus cases

Concomitant Rotavirus and Salmonella Infections in Children with Acute Diarrhea

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Wen-Tzong Lan

2009-02-01

Conclusion: Concomitant rotavirus and Salmonella infections accounted for 3.7% of cases in this study. Patients in group C (30.0% had a significantly higher incidence of hypokalemia than group R (7.3% or S (8.8%. Group C consisted of 33 cases of the 895 reviewed cases (3.7%. In a child with rotavirus gastroenteritis, concomitant infection with Salmonella should be considered if the child has sustained a high fever (≥ 39°C for over 4 days and a green stool with mucus and blood.

The role of La2O3 in direct laser sintering of submicrometre WC-Cop/Cu MMCs

International Nuclear Information System (INIS)

Gu Dongdong; Shen Yifu

2008-01-01

This paper presents a detailed investigation of the influence of rare earth (RE) oxide (La 2 O 3 ) addition on densification and microstructure of direct laser sintered submicrometre WC-Co p /Cu metal matrix composites (MMCs) possessing 50.0 wt% reinforcement (WC-Co). It was found that with increasing La 2 O 3 addition to a suitable amount (1.0 wt%), the particulate dispersion was homogenized and the particulate/matrix interfacial bonding was improved. However, with an excessive addition of La 2 O 3 (1.5 wt%), a heterogeneous microstructure consisting of highly accumulated particulates was present. The exact metallurgical roles of RE element in direct laser sintering of particulate reinforced MMCs were addressed. It showed that a proper addition of RE element (i) decreased surface tension of the melt and enhanced solid-liquid wettability; (ii) dragged and/or pinned grain/phase boundaries and resisted grain coarsening and particulate aggregating. However, the balling phenomenon occurred and the activity of RE atoms decreased at an even higher La 2 O 3 content, thereby producing detrimental effects on laser forming ability

Roles of outer capsid proteins as determinants of pathogenicity and host range restriction of avian rotaviruses in a suckling mouse model

International Nuclear Information System (INIS)

Mori, Yoshio; Borgan, Mohammed Ali; Takayama, Mutsuyo; Ito, Naoto; Sugiyama, Makoto; Minamoto, Nobuyuki

2003-01-01

We previously demonstrated that a pigeon rotavirus, PO-13, but not turkey strains Ty-3 and Ty-1 and a chicken strain, Ch-1, induced diarrhea in heterologous suckling mice. In this study, it was suggested that these avirulent strains, but not PO-13, were inactivated immediately in gastrointestinal tracts of suckling mice when they were orally inoculated. To determine which viral proteins contribute to the differences between the pathogenicitiy and the inactivation of PO-13 and Ty-3 in suckling mice, six PO-13 x Ty-3 reassortant strains that had the genes of the outer capsid proteins, VP4 and VP7, derived from the opposite strain were prepared and were orally inoculated to suckling mice. A single strain that had both PO-13 VP4 and VP7 with the genetic background of Ty-3 had an intermediate virulence for suckling mice. Three strains with Ty-3 VP7, regardless of the origin of VP4, rapidly disappeared from gastrointestinal tracts of suckling mice. These results indicated that the difference between the pathogenicity of PO-13 and that of Ty-3 was mainly dependent on both their VP4 and VP7. In particular, VP7 was found to be related to the inactivation of Ty-3 in gastrointestinal tracts of suckling mice

Household transmission of rotavirus in a community with rotavirus vaccination in Quininde, Ecuador.

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Ben Lopman

Full Text Available We studied the transmission of rotavirus infection in households in peri-urban Ecuador in the vaccination era.Stool samples were collected from household contacts of child rotavirus cases, diarrhea controls and healthy controls following presentation of the index child to health facilities. Rotavirus infection status of contacts was determined by RT-qPCR. We examined factors associated with transmissibility (index-case characteristics and susceptibility (household-contact characteristics.Amongst cases, diarrhea controls and healthy control household contacts, infection attack rates (iAR were 55%, 8% and 2%, (n = 137, 130, 137 respectively. iARs were higher from index cases with vomiting, and amongst siblings. Disease ARs were higher when the index child was <18 months and had vomiting, with household contact <10 years and those sharing a room with the index case being more susceptible. We found no evidence of asymptomatic infections leading to disease transmission.Transmission rates of rotavirus are high in households with an infected child, while background infections are rare. We have identified factors associated with transmission (vomiting/young age of index case and susceptibility (young age/sharing a room/being a sibling of the index case. Vaccination may lead to indirect benefits by averting episodes or reducing symptoms in vaccinees.

Rotavirus Viremia and Extraintestinal Viral Infection in the Neonatal Rat Model

Science.gov (United States)

Crawford, Sue E.; Patel, Dinesh G.; Cheng, Elly; Berkova, Zuzana; Hyser, Joseph M.; Ciarlet, Max; Finegold, Milton J.; Conner, Margaret E.; Estes, Mary K.

2006-01-01

Rotaviruses infect mature, differentiated enterocytes of the small intestine and, by an unknown mechanism, escape the gastrointestinal tract and cause viremia. The neonatal rat model of rotavirus infection was used to determine the kinetics of viremia, spread, and pathology of rotavirus in extraintestinal organs. Five-day-old rat pups were inoculated intragastrically with an animal (RRV) or human (HAL1166) rotavirus or phosphate-buffered saline. Blood was collected from a subset of rat pups, and following perfusion to remove residual blood, organs were removed and homogenized to analyze rotavirus-specific antigen by enzyme-linked immunosorbent assay and infectious rotavirus by fluorescent focus assay or fixed in formalin for histology and immunohistochemistry. Viremia was detected following rotavirus infection with RRV and HAL1166. The RRV 50% antigenemia dose was 1.8 × 103 PFU, and the 50% diarrhea dose was 7.7 × 105 PFU, indicating that infection and viremia occurred in the absence of diarrhea and that detecting rotavirus antigen in the blood was a more sensitive measure of infection than diarrhea. Rotavirus antigens and infectious virus were detected in multiple organs (stomach, intestines, liver, lungs, spleen, kidneys, pancreas, thymus, and bladder). Histopathological changes due to rotavirus infection included acute inflammation of the portal tract and bile duct, microsteatosis, necrosis, and inflammatory cell infiltrates in the parenchymas of the liver and lungs. Colocalization of structural and nonstructural proteins with histopathology in the liver and lungs indicated that the histological changes observed were due to rotavirus infection and replication. Replicating rotavirus was also detected in macrophages in the lungs and blood vessels, indicating a possible mechanism of rotavirus dissemination. Extraintestinal infectious rotavirus, but not diarrhea, was observed in the presence of passively or actively acquired rotavirus-specific antibody. These

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

DEFF Research Database (Denmark)

Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik

2013-01-01

BACKGROUND: The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically...... and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. METHODS: Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation...... with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. RESULTS: The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene...

Effect of pentavalent rotavirus vaccine introduction on hospital admissions for diarrhoea and rotavirus in children in Rwanda: a time-series analysis.

Science.gov (United States)

Ngabo, Fidele; Tate, Jacqueline E; Gatera, Maurice; Rugambwa, Celse; Donnen, Philippe; Lepage, Philippe; Mwenda, Jason M; Binagwaho, Agnes; Parashar, Umesh D

2016-02-01

In May, 2012, Rwanda became the first low-income African country to introduce pentavalent rotavirus vaccine into its routine national immunisation programme. Although the potential health benefits of rotavirus vaccination are huge in low-income African countries that account for more than half the global deaths from rotavirus, concerns remain about the performance of oral rotavirus vaccines in these challenging settings. We conducted a time-series analysis to examine trends in admissions to hospital for non-bloody diarrhoea in children younger than 5 years in Rwanda between Jan 1, 2009, and Dec 31, 2014, using monthly discharge data from the Health Management Information System. Additionally, we reviewed the registries in the paediatric wards at six hospitals from 2009 to 2014 and abstracted the number of total admissions and admissions for diarrhoea in children younger than 5 years by admission month and age group. We studied trends in admissions specific to rotavirus at one hospital that had undertaken active rotavirus surveillance from 2011 to 2014. We assessed changes in rotavirus epidemiology by use of data from eight active surveillance hospitals. Compared with the 2009-11 prevaccine baseline, hospital admissions for non-bloody diarrhoea captured by the Health Management Information System fell by 17-29% from a pre-vaccine median of 4051 to 2881 in 2013 and 3371 in 2014, admissions for acute gastroenteritis captured in paediatric ward registries decreased by 48-49%, and admissions specific to rotavirus captured by active surveillance fell by 61-70%. The greatest effect was recorded in children age-eligible to be vaccinated, but we noted a decrease in the proportion of children with diarrhoea testing positive for rotavirus in almost every age group. The number of admissions to hospital for diarrhoea and rotavirus in Rwanda fell substantially after rotavirus vaccine implementation, including among older children age-ineligible for vaccination, suggesting

Rotavirus RRV associates with lipid membrane microdomains during cell entry

International Nuclear Information System (INIS)

Isa, Pavel; Realpe, Mauricio; Romero, Pedro; Lopez, Susana; Arias, Carlos F.

2004-01-01

Rotavirus cell entry is a multistep process, not completely understood, which requires at least four interactions between the virus and cell surface molecules. In this work, we investigated the role of the sphingolipid- and cholesterol-enriched lipid microdomains (rafts) in the entry of rotavirus strain RRV to MA104 cells. We found that ganglioside GM1, integrin subunits α2 and β3, and the heat shock cognate protein 70 (hsc70), all of which have been implicated as rotavirus receptors, are associated with TX-100 and Lubrol WX detergent-resistant membranes (DRMs). Integrin subunits α2 and β3 were found to be particularly enriched in DRMs resistant to lysis by Lubrol WX. When purified RRV particles were incubated with cells at 4 deg. C, about 10% of the total infectious virus was found associated with DRMs, and the DRM-associated virus increased to 37% in Lubrol-resistant membrane domains after 60-min incubation at 37 deg. C. The virus was excluded from DRMs if the cells were treated with methyl-β-cyclodextrin (MβCD). Immunoblot analysis of the viral proteins showed that the virus surface proteins became enriched in DRMs upon incubation at 37 deg. C, being almost exclusively localized in Lubrol-resistant DRMs after 60 min. These data suggest that detergent-resistant membrane domains play an important role in the cell entry of rotaviruses, which could provide a platform to facilitate the efficient interaction of the rotavirus receptors with the virus particle

Subunit Rotavirus Vaccine Administered Parenterally to Rabbits Induces Active Protective Immunity

Science.gov (United States)

Ciarlet, Max; Crawford, Sue E.; Barone, Christopher; Bertolotti-Ciarlet, Andrea; Ramig, Robert F.; Estes, Mary K.; Conner, Margaret E.

1998-01-01

Virus-like particles (VLPs) are being evaluated as a candidate rotavirus vaccine. The immunogenicity and protective efficacy of different formulations of VLPs administered parenterally to rabbits were tested. Two doses of VLPs (2/6-, G3 2/6/7-, or P[2], G3 2/4/6/7-VLPs) or SA11 simian rotavirus in Freund’s adjuvants, QS-21 (saponin adjuvant), or aluminum phosphate (AlP) were administered. Serological and mucosal immune responses were evaluated in all vaccinated and control rabbits before and after oral challenge with 103 50% infective doses of live P[14], G3 ALA lapine rotavirus. All VLP- and SA11-vaccinated rabbits developed high levels of rotavirus-specific serum and intestinal immunoglobulin G (IgG) antibodies but not intestinal IgA antibodies. SA11 and 2/4/6/7-VLPs afforded similar but much higher mean levels of protection than 2/6/7- or 2/6-VLPs in QS-21. The presence of neutralizing antibodies to VP4 correlated (P < 0.001, r = 0.55; Pearson’s correlation coefficient) with enhanced protection rates, suggesting that these antibodies are important for protection. Although the inclusion of VP4 resulted in higher mean protection levels, high levels of protection (87 to 100%) from infection were observed in individual rabbits immunized with 2/6/7- or 2/6-VLPs in Freund’s adjuvants. Therefore, neither VP7 nor VP4 was absolutely required to achieve protection from infection in the rabbit model when Freund’s adjuvant was used. Our results show that VLPs are immunogenic when administered parenterally to rabbits and that Freund’s adjuvant is a better adjuvant than QS-21. The use of the rabbit model may help further our understanding of the critical rotavirus proteins needed to induce active protection. VLPs are a promising candidate for a parenterally administered subunit rotavirus vaccine. PMID:9765471

Electrochemical properties of mixed WC and Pt-black powders

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MAJA D. OBRADOVIC

2008-12-01

Full Text Available The electrochemical characteristics of a mixture of Pt-black and WC powders and its catalytic activity for methanol and formic acid oxidation were investigated in acid solution. XRD and AFM measurements revealed that the WC powder employed for the investigation was a single-phase material consisting of crystallites/spherical particles of average size of about 50 nm, which were agglomerated into much larger particles. Cyclic voltammetry showed that the WC underwent electrochemical oxidation, producing tungstate species. In the case of the mixed Pt + WC powders, the tungstate species were deposited on the Pt as a thin film of hydrous tungsten oxide. Enhanced hydrogen intercalation in the hydrous tungsten oxide was observed and it was proposed to be promoted in mixed powders by the presence of hydrogen adatoms on bare Pt sites. The determination of Pt surface area in the Pt + WC layer by stripping of underpotentially deposited Cu revealed that the entire Pt surface was accessible for underpotential deposition of Cu. Investigation of the electrochemical oxidation of methanol and formic acid on Pt + WC and pure Pt layers did not indicate electrocatalytic promotion due to the presence of WC.

WC1 is a hybrid γδ TCR coreceptor and pattern recognition receptor for pathogenic bacteria.

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Hsu, Haoting; Chen, Chuang; Nenninger, Ariel; Holz, Lauren; Baldwin, Cynthia L; Telfer, Janice C

2015-03-01

WC1 proteins are uniquely expressed on γδ T cells and belong to the scavenger receptor cysteine-rich (SRCR) superfamily. While present in variable, and sometimes high, numbers in the genomes of mammals and birds, in cattle there are 13 distinct genes (WC1-1 to WC1-13). All bovine WC1 proteins can serve as coreceptors for the TCR in a tyrosine phosphorylation dependent manner, and some are required for the γδ T cell response to Leptospira. We hypothesized that individual WC1 receptors encode Ag specificity via coligation of bacteria with the γδ TCR. SRCR domain binding was directly correlated with γδ T cell response, as WC1-3 SRCR domains from Leptospira-responsive cells, but not WC1-4 SRCR domains from Leptospira-nonresponsive cells, bound to multiple serovars of two Leptospira species, L. borgpetersenii, and L. interrogans. Three to five of eleven WC1-3 SRCR domains, but none of the eleven WC1-4 SRCR domains, interacted with Leptospira spp. and Borrelia burgdorferi, but not with Escherichia coli or Staphylococcus aureus. Mutational analysis indicated that the active site for bacterial binding in one of the SRCR domains is composed of amino acids in three discontinuous regions. Recombinant WC1 SRCR domains with the ability to bind leptospires inhibited Leptospira growth. Our data suggest that WC1 gene arrays play a multifaceted role in the γδ T cell response to bacteria, including acting as hybrid pattern recognition receptors and TCR coreceptors, and they may function as antimicrobials. Copyright © 2015 by The American Association of Immunologists, Inc.

[Prospective study of rotavirus infection in a maternity unit. Demonstration of a nosocomial infection].

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Brussieux, J; Boisivon, A; Michelon, B

1985-10-01

Eighty-eight children born at the maternity hospital in Saint-Germain-en-Laye between May 24 and June 7, 1983 were followed clinically, with a special supervision concerning stools, weight curves and the way of feeding. Stool samplings looking for Rotavirus were performed in all the children and their mothers, at the 3rd and 6th days of life. No mother was found with Rotavirus infection. In neonates, Rotavirus excretion was significantly related to a slow down in weight curves and the occurrence of diarrhea. All rotaviruses had the same electrophoretype. Breast-feeding had an undeniable protective effect.

Rotavirus gastroenteritis in children in 4 regions in Brazil: a hospital-based surveillance study.

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Munford, Veridiana; Gilio, Alfredo Elias; de Souza, Eloisa Correa; Cardoso, Debora Morais; Cardoso, Divina das Dores de Paula; Borges, Ana Maria Tavares; Costa, Paulo Sergio Sucasas da; Melgaço, Irene Angela Melo; Rosa, Humberto; Carvalho, Paulo Roberto Antonacci; Goldani, Marcelo Zubaran; Moreira, Edson Duarte; Santana, Ciria; El Khoury, Antoine; Ikedo, Fabio; Rácz, Maria Lucia

2009-11-01

Rotavirus is a major cause of gastroenteritis in children. Knowledge of rotavirus genotypes is important for vaccination strategies. During 2005-2006, rotavirus surveillance studies were conducted in São Paulo, Salvador, Goiânia, and Porto Alegre, Brazil. Stool samples were collected from children <5 years of age who had diarrhea and were screened by the Rotaclone Enzyme Immunoassay for the presence of rotavirus. Confirmed rotavirus-positive samples were characterized for P and G genotypes by reverse-transcriptase polymerase chain reaction. A total of 510 stool samples were collected. Of these, 221 (43.3%) were positive for rotavirus. Overall, G9 was the predominant G type, followed by G2, and G1; P[4] and P[8] were the predominant P types. The most frequent G/P genotype combination detected was G2P[4], followed by G9P[8], G9P[4], and G1P[8]. G2P[4] was the predominant type in Goiânia and Salvador; G9P[8] and G1P[8] were predominant in São Paulo and Porto Alegre, respectively. The prevalence, seasonality, and genotype distribution of rotavirus infection varied in different regions in Brazil. With immunization programs, continuous monitoring of rotavirus types is important to detect novel and emerging strains.

Impact of rotavirus vaccines in low and middle-income countries.

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Sindhu, Kulandaipalayam Natarajan Chella; Babji, Sudhir; Ganesan, Santhosh Kumar

2017-10-01

Rotavirus vaccines are playing a pivotal role in improving lives of infants and young children in low and middle-income countries (LMICs). Many of these countries have adopted the vaccine into their routine immunization, whereas others are considering introduction. This article provides an update on the impact of rotavirus vaccines in LMICs on morbidity and mortality in children aged less than 5 years, and their cost-effectiveness. The WHO, in 2013, updated its recommendation to prioritize introduction of rotavirus vaccines in the routine immunization schedule, without age restrictions. Despite the decreased efficacy of the vaccines in LMICs, data from Sub-Saharan Africa have demonstrated a decrease in rotavirus-related morbidity, with some sites reporting an indirect protective effect on children age ineligible to receive the vaccine. Even with improvements in sanitation, nutritional status in children, and other health-related indices in LMICs, the use of rotavirus vaccines will play an important role in preventing rotavirus-related gastroenteritis. Economic models predict a reduction in economic burden because of rotavirus-related health costs, making vaccine introduction cost-effective in resource-constrained settings. Increasing evidence from impact studies shows the significant impact of rotavirus vaccination on hospitalizations and economic burden because of rotavirus gastroenteritis in LMICs. Universal rotavirus vaccination is recommended, and introductions should be monitored by robust surveillance systems to measure effectiveness and impact.

Hospitalizations due to rotavirus gastroenteritis in Catalonia, Spain, 2003-2008

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2011-01-01

Background Rotavirus is the most common cause of severe gastroenteritis among young children in Spain and worldwide. We evaluated hospitalizations due to community and hospital-acquired rotavirus gastroenteritis (RVGE) and estimated related costs in children under 5 years old in Catalonia, Spain. Results We analyzed hospital discharge data from the Catalan Health Services regarding hospital admissions coded as infectious gastroenteritis in children under 5 for the period 2003-2008. In order to estimate admission incidence, we used population estimates for each study year published by the Statistic Institut of Catalonia (Idescat). The costs associated with hospital admissions due to rotavirus diarrhea were estimated for the same years. A decision tree model was used to estimate the threshold cost of rotavirus vaccine to achieve cost savings from the healthcare system perspective in Catalonia. From 2003 through 2008, 10655 children under 5 years old were admitted with infectious gastroenteritis (IGE). Twenty-two percent of these admissions were coded as RVGE, yielding an estimated average annual incidence of 104 RVGE hospitalizations per 100000 children in Catalonia. Eighty seven percent of admissions for RVGE occurred during December through March. The mean hospital stay was 3.7 days, 0.6 days longer than for other IGE. An additional 892 cases of presumed nosocomial RVGE were detected, yielding an incidence of 2.5 cases per 1000 child admissions. Total rotavirus hospitalization costs due to community acquired RVGE for the years 2003 and 2008 were 431,593 and 809,224 €, respectively. According to the estimated incidence and hospitalization costs, immunization would result in health system cost savings if the cost of the vaccine was 1.93 € or less. At a vaccine cost of 187 € the incremental cost per hospitalization prevented is 195,388 € (CI 95% 159,300; 238,400). Conclusions The burden of hospitalizations attributable to rotavirus appeared to be lower in

Efficacy of pentavalent rotavirus vaccine against severe rotavirus gastroenteritis in infants in developing countries in sub-Saharan Africa: a randomised, double-blind, placebo-controlled trial.

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Armah, George E; Sow, Samba O; Breiman, Robert F; Dallas, Michael J; Tapia, Milagritos D; Feikin, Daniel R; Binka, Fred N; Steele, A Duncan; Laserson, Kayla F; Ansah, Nana A; Levine, Myron M; Lewis, Kristen; Coia, Michele L; Attah-Poku, Margaret; Ojwando, Joel; Rivers, Stephen B; Victor, John C; Nyambane, Geoffrey; Hodgson, Abraham; Schödel, Florian; Ciarlet, Max; Neuzil, Kathleen M

2010-08-21

in a vaccine efficacy against severe rotavirus gastroenteritis of 39.3% (95% CI 19.1-54.7, p=0.0003 for efficacy >0%). Median follow-up in both groups was 527 days starting 14 days after the third dose of vaccine or placebo was given. 42 (1.5%) of 2723 infants assigned to receive vaccine and 45 (1.7%) of 2724 infants assigned to receive placebo had a serious adverse event within 14 days of any dose. The most frequent serious adverse event was gastroenteritis (vaccine 17 [0.6%]; placebo 17 [0.6%]). Pentavalent rotavirus vaccine is effective against severe rotavirus gastroenteritis in the first 2 years of life in African countries with high mortality in infants younger than 5 years. We support WHO's recommendation for adoption of rotavirus vaccine into national expanded programmes on immunisation in Africa. PATH (GAVI Alliance grant) and Merck. Copyright 2010 Elsevier Ltd. All rights reserved.

Rotavirus vaccines: safety, efficacy and public health impact.

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Gray, J

2011-09-01

Rotaviruses are the cause of acute gastroenteritis, and disease is widespread amongst infants and young children throughout the world. Also, rotavirus is associated with significant mortality in developing countries with more than 500 000 children dying each year as a result of the severe dehydration associated with rotavirus disease. Efforts have been ongoing for more than 30 years to develop a safe and effective rotavirus vaccine. Currently, two vaccines, RotaRix and RotaTeq, have been licensed for use in many countries throughout the world following comprehensive safety and efficiency trials. Monitoring their effectiveness after licensure has confirmed that their incorporation into early childhood vaccination schedules can significantly prevent severe rotavirus diarrhoea, which would have resulted in hospitalizations, emergency room visits or increased diarrhoea-related mortality. Although the efficacy of both vaccines is lower at approximately 40-59% in developing countries, their use could significantly reduce the mortality associated with rotavirus disease that is concentrated in these countries. © 2011 The Association for the Publication of the Journal of Internal Medicine.

A systematic review of anti-rotavirus serum IgA antibody titer as a potential correlate of rotavirus vaccine efficacy.

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Patel, Manish; Glass, Roger I; Jiang, Baoming; Santosham, Mathuram; Lopman, Ben; Parashar, Umesh

2013-07-15

Identifying an immunological correlate of protection for rotavirus vaccines (Rotarix [RV1] and RotaTeq [RV5]) would substantially facilitate testing of interventions for improving efficacy in developing countries and evaluating additional candidate rotavirus vaccines. We accessed PubMed and ClinicalTrials.gov to identify immunogenicity and efficacy trials for RV1 and RV5 to correlate anti-rotavirus serum immunoglobulin A (IgA) antibody titers vs efficacy in regions stratified by all-cause under-5 mortality rates (u5MR). We established a cutoff point for IgA geometric mean concentration or titer (GMC) that predicted lower efficacy and calculated pooled vaccine efficacy among countries with high vs low IgA titers. We observed an inverse correlation between u5MR and IgA titers for RV1 (r(2) = 0.72; P efficacy and IgA titers for both vaccines (r(2) = 0.56; P = .005). Postimmunization anti-rotavirus IgA GMC vaccine efficacy. Efficacy during first 2 years of life was significantly lower among countries with IgA GMC 90 (85%; 95% CI, 82-88). We observed a significant correlation between IgA titers and rotavirus vaccine efficacy and hypothesize that a critical level of IgA antibody titer is associated with a sufficient level of sustained protection after rotavirus vaccination.

Performance of rotavirus vaccines in developed and developing countries

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Jiang, Victoria; Jiang, Baoming; Tate, Jacqueline; Parashar, Umesh D; Patel, Manish M

2010-01-01

The World Health Organization estimates that rotavirus diarrhea results in approximately half a million deaths and approximately 2.4 million hospitalizations in developing countries each year. Two live oral rotavirus vaccines, RotaTeq® (RV 5; Merck) and Rotarix® (RV 1; GlaxoSmithKline) with good efficacy against severe rotavirus disease and a reassuring safety profile could substantially impact the burden of rotavirus disease. In April 2009, WHO provided a recommendation for global introducti...

Determinants of Rotavirus Transmission: A Lag Nonlinear Time Series Analysis.

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van Gaalen, Rolina D; van de Kassteele, Jan; Hahné, Susan J M; Bruijning-Verhagen, Patricia; Wallinga, Jacco

2017-07-01

Rotavirus is a common viral infection among young children. As in many countries, the infection dynamics of rotavirus in the Netherlands are characterized by an annual winter peak, which was notably low in 2014. Previous study suggested an association between weather factors and both rotavirus transmission and incidence. From epidemic theory, we know that the proportion of susceptible individuals can affect disease transmission. We investigated how these factors are associated with rotavirus transmission in the Netherlands, and their impact on rotavirus transmission in 2014. We used available data on birth rates and rotavirus laboratory reports to estimate rotavirus transmission and the proportion of individuals susceptible to primary infection. Weather data were directly available from a central meteorological station. We developed an approach for detecting determinants of seasonal rotavirus transmission by assessing nonlinear, delayed associations between each factor and rotavirus transmission. We explored relationships by applying a distributed lag nonlinear regression model with seasonal terms. We corrected for residual serial correlation using autoregressive moving average errors. We inferred the relationship between different factors and the effective reproduction number from the most parsimonious model with low residual autocorrelation. Higher proportions of susceptible individuals and lower temperatures were associated with increases in rotavirus transmission. For 2014, our findings suggest that relatively mild temperatures combined with the low proportion of susceptible individuals contributed to lower rotavirus transmission in the Netherlands. However, our model, which overestimated the magnitude of the peak, suggested that other factors were likely instrumental in reducing the incidence that year.

Health and economic impact of rotavirus vaccination in GAVI-eligible countries

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Slichter David

2010-05-01

Full Text Available Abstract Background Rotavirus infection is responsible for about 500,000 deaths annually, and the disease burden is disproportionately borne by children in low-income countries. Recently the World Health Organization (WHO has released a global recommendation that all countries include infant rotavirus vaccination in their national immunization programs. Our objective was to provide information on the expected health, economic and financial consequences of rotavirus vaccines in the 72 GAVI support-eligible countries. Methods We synthesized population-level data from various sources (primarily from global-level databases for the 72 countries eligible for the support by the GAVI Alliance (GAVI-eligible countries in order to estimate the health and economic impact associated with rotavirus vaccination programs. The primary outcome measure was incremental cost (in 2005 international dollars [I$] per disability-adjusted life year (DALY averted. We also projected the expected reduction in rotavirus disease burden and financial resources required associated with a variety of scale-up scenarios. Results Under the base-case assumptions (70% coverage, vaccinating one single birth cohort would prevent about 55% of rotavirus associated deaths in the 72 GAVI-eligible countries. Assuming I$25 per vaccinated child (~$5 per dose, the number of countries with the incremental cost per DALY averted less than I$200 was 47. Using the WHO's cost-effectiveness threshold based on per capita GDP, the vaccines were considered cost-effective in 68 of the 72 countries (~94%. A 10-year routine rotavirus vaccination would prevent 0.9-2.8 million rotavirus associated deaths among children under age 5 in the poorest parts of the world, depending on vaccine scale-up scenarios. Over the same intervention period, rotavirus vaccination programs would also prevent 4.5-13.3 million estimated cases of hospitalization and 41-107 million cases of outpatient clinic visits in the same

Influenza A and B Virus Intertypic Reassortment through Compatible Viral Packaging Signals

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Baker, Steven F.; Nogales, Aitor; Finch, Courtney; Tuffy, Kevin M.; Domm, William; Perez, Daniel R.; Topham, David J.

2014-01-01

ABSTRACT Influenza A and B viruses cocirculate in humans and together cause disease and seasonal epidemics. These two types of influenza viruses are evolutionarily divergent, and exchange of genetic segments inside coinfected cells occurs frequently within types but never between influenza A and B viruses. Possible mechanisms inhibiting the intertypic reassortment of genetic segments could be due to incompatible protein functions of segment homologs, a lack of processing of heterotypic segments by influenza virus RNA-dependent RNA polymerase, an inhibitory effect of viral proteins on heterotypic virus function, or an inability to specifically incorporate heterotypic segments into budding virions. Here, we demonstrate that the full-length hemagglutinin (HA) of prototype influenza B viruses can complement the function of multiple influenza A viruses. We show that viral noncoding regions were sufficient to drive gene expression for either type A or B influenza virus with its cognate or heterotypic polymerase. The native influenza B virus HA segment could not be incorporated into influenza A virus virions. However, by adding the influenza A virus packaging signals to full-length influenza B virus glycoproteins, we rescued influenza A viruses that possessed HA, NA, or both HA and NA of influenza B virus. Furthermore, we show that, similar to single-cycle infectious influenza A virus, influenza B virus cannot incorporate heterotypic transgenes due to packaging signal incompatibilities. Altogether, these results demonstrate that the lack of influenza A and B virus reassortants can be attributed at least in part to incompatibilities in the virus-specific packaging signals required for effective segment incorporation into nascent virions. IMPORTANCE Reassortment of influenza A or B viruses provides an evolutionary strategy leading to unique genotypes, which can spawn influenza A viruses with pandemic potential. However, the mechanism preventing intertypic reassortment or

Identification of swine H1N2/pandemic H1N1 reassortant influenza virus in pigs, United States.

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Ali, Ahmed; Khatri, Mahesh; Wang, Leyi; Saif, Yehia M; Lee, Chang-Won

2012-07-06

In October and November 2010, novel H1N2 reassortant influenza viruses were identified from pigs showing mild respiratory signs that included cough and depression. Sequence and phylogenetic analysis showed that the novel H1N2 reassortants possesses HA and NA genes derived from recent H1N2 swine isolates similar to those isolated from Midwest. Compared to the majority of reported reassortants, both viruses preserved human-like host restrictive and putative antigenic sites in their HA and NA genes. The four internal genes, PB2, PB1, PA, and NS were similar to the contemporary swine triple reassortant viruses' internal genes (TRIG). Interestingly, NP and M genes of the novel reassortants were derived from the 2009 pandemic H1N1. The NP and M proteins of the two isolates demonstrated one (E16G) and four (G34A, D53E, I109T, and V313I) amino acid changes in the M2 and NP proteins, respectively. Similar amino acid changes were also noticed upon incorporation of the 2009 pandemic H1N1 NP in other reassortant viruses reported in the U.S. Thus the role of those amino acids in relation to host adaptation need to be further investigated. The reassortments of pandemic H1N1 with swine influenza viruses and the potential of interspecies transmission of these reassortants from swine to other species including human indicate the importance of systematic surveillance of swine population to determine the origin, the prevalence of similar reassortants in the U.S. and their impact on both swine production and public health. Copyright © 2012 Elsevier B.V. All rights reserved.

Detection of rotavirus and other enteropathogens in children hospitalized with acute gastroenteritis in Havana, Cuba.

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Ribas, María de Los Angeles; Tejero, Yahisel; Cordero, Yanislet; de Los Angeles León, María; Rodriguez, Misladys; Perez-Lastre, Jorge; Triana, Thelma; Guerra, Mabel; Ayllón, Lucía; Escalante, Gladys; Hadad, Jorge

2015-08-01

The aim of the study was to diagnose infections with rotavirus and other enteric pathogens in children under five years old with acute gastroenteritis and to identify the most common epidemiological and clinical characteristics of these pathogens. The study was conducted using 110 stool samples from the same number of children under five years old who were inpatients at three paediatric hospitals in Havana, Cuba, between October and December 2011. The samples were tested for rotavirus and other enteric pathogens using traditional and molecular microbiological methods. Pathogens were detected in 85 (77.3 %) of the children. Rotavirus was the most commonly found, appearing in 54.5 % of the children, followed by bacteria (29 %) and parasites (10.9 %). Other viral pathogens detected included adenovirus (6.4 %) and astrovirus (3.6 %). In rotavirus-positives cases, at least one other pathogen was detected, usually a bacterium (26.6 %). More than three episodes of watery diarrhea in 24 hours were observed in 78.3 % of the cases. Dehydration was found in 30 (50 %) rotavirus-positive children, of whom seven (11.6 %) were transferred to an intensive care unit due to complications of metabolic acidosis. Rotavirus was most commonly observed among children under 12 months old (65 %). The highest incidence of infection occurred in children who were under the care of a relative at home (78.3 %), had not been breastfed (65 %), or had been breastfed for less than six months (28.3 %). The genotype combinations most frequently found were G9P8 (28.3 %) and G1P8 (10 %). This study demonstrates the presence of rotavirus and other enteric pathogens as causes of gastroenteritis in hospitalized infants and young children in Cuba.

Delayed Dosing of Oral Rotavirus Vaccine Demonstrates Decreased Risk of Rotavirus Gastroenteritis Associated With Serum Zinc: A Randomized Controlled Trial.

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Colgate, E Ross; Haque, Rashidul; Dickson, Dorothy M; Carmolli, Marya P; Mychaleckyj, Josyf C; Nayak, Uma; Qadri, Firdausi; Alam, Masud; Walsh, Mary Claire; Diehl, Sean A; Zaman, K; Petri, William A; Kirkpatrick, Beth D

2016-09-01

Rotavirus is the world's leading cause of childhood diarrheal death. Despite successes, oral rotavirus vaccines are less effective in developing countries. In an urban slum of Dhaka, we performed active diarrhea surveillance to evaluate monovalent G1P[8] rotavirus vaccine (RV1) efficacy and understand variables contributing to risk of rotavirus diarrhea (RVD). We performed a randomized controlled trial of monovalent oral rotavirus vaccine (RV1). Seven hundred healthy infants received RV1 or no RV1 (1:1) using delayed dosing (10 and 17 weeks) and were followed for 1 year. Intensive diarrhea surveillance was performed. The primary outcome was ≥1 episode of RVD. Nutritional, socioeconomic, and immunologic factors were assessed by logistic regression best-subsets analysis for association with risk of RVD and interactions with vaccine arm. Incidence of all RVD was 38.3 cases per 100 person-years. Per-protocol RV1 efficacy was 73.5% (95% confidence interval [CI], 45.8%-87.0%) against severe RVD and 51% (95% CI, 33.8%-63.7%) against all RVD. Serum zinc level (odds ratio [OR], 0.77; P = .002) and lack of rotavirus immunoglobulin A (IgA) seroconversion (OR, 1.95; P = .018) were associated with risk of RVD, independent of vaccination status. Water treatment and exclusive breastfeeding were of borderline significance. Factors not associated with RVD included height for age at 10 weeks, vitamin D, retinol binding protein, maternal education, household income, and sex. In an urban slum with high incidence of RVD, the efficacy of RV1 against severe RVD was higher than anticipated in the setting of delayed dosing. Lower serum zinc level and lack of IgA seroconversion were associated with increased risk of RVD independent of vaccination. NCT01375647. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Swine Influenza Virus PA and Neuraminidase Gene Reassortment into Human H1N1 Influenza Virus Is Associated with an Altered Pathogenic Phenotype Linked to Increased MIP-2 Expression.

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Dlugolenski, Daniel; Jones, Les; Howerth, Elizabeth; Wentworth, David; Tompkins, S Mark; Tripp, Ralph A

2015-05-01

Swine are susceptible to infection by both avian and human influenza viruses, and this feature is thought to contribute to novel reassortant influenza viruses. In this study, the influenza virus reassortment rate in swine and human cells was determined. Coinfection of swine cells with 2009 pandemic H1N1 virus (huH1N1) and an endemic swine H1N2 (A/swine/Illinois/02860/09) virus (swH1N2) resulted in a 23% reassortment rate that was independent of α2,3- or α2,6-sialic acid distribution on the cells. The reassortants had altered pathogenic phenotypes linked to introduction of the swine virus PA and neuraminidase (NA) into huH1N1. In mice, the huH1N1 PA and NA mediated increased MIP-2 expression early postinfection, resulting in substantial pulmonary neutrophilia with enhanced lung pathology and disease. The findings support the notion that swine are a mixing vessel for influenza virus reassortants independent of sialic acid distribution. These results show the potential for continued reassortment of the 2009 pandemic H1N1 virus with endemic swine viruses and for reassortants to have increased pathogenicity linked to the swine virus NA and PA genes which are associated with increased pulmonary neutrophil trafficking that is related to MIP-2 expression. Influenza A viruses can change rapidly via reassortment to create a novel virus, and reassortment can result in possible pandemics. Reassortments among subtypes from avian and human viruses led to the 1957 (H2N2 subtype) and 1968 (H3N2 subtype) human influenza pandemics. Recent analyses of circulating isolates have shown that multiple genes can be recombined from human, avian, and swine influenza viruses, leading to triple reassortants. Understanding the factors that can affect influenza A virus reassortment is needed for the establishment of disease intervention strategies that may reduce or preclude pandemics. The findings from this study show that swine cells provide a mixing vessel for influenza virus reassortment

High growth reassortant influenza vaccine viruses: new approaches to their control.

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Robertson, J S; Nicolson, C; Newman, R; Major, D; Dunleavy, U; Wood, J M

1992-09-01

When a new strain of an influenza virus is required to be incorporated into influenza vaccine, attempts are made to recombine such strains with laboratory adapted viruses, which will grow to high titre in order to improve the yield of the vaccine strain. It is important that such high growth reassortant vaccine strains are not contaminated with genes coding for the antigenic determinants of the high growth laboratory strain. We describe the characterization of two recent high growth reassortants and the application of the polymerase chain reaction to ensure their genetic identity and purity.

Gene-Specific-Candidate-Driven Study to decipher Genetic Predisposition to Rotavirus Infection

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Kshitija Rane-Yadav

2017-10-01

Full Text Available Recent report of WHO shows 113000 children in India succumb to death due to Rotavirus diarrhea. Lack of knowledge about pathogenesis of virus has led to lack of therapy for severely infected patients. Previous studies have found that, animal rotavirus requires sialyl glycan moieties on cell surface for pathogenesis. Present study states that human rotaviruses also follows same path and this specificity of virus leads to host genetic predisposition for the infection as well as the disease. Two hundred children less than 5 years of age clinically suspected of viral diarrhea were screened for rotavirus infection. EDTA blood was processed for analyzing DNA sequences of various fucosyltransferase genes. Lewis antigens which are secretory form of ABO Histo Blood Group Antigens were correlated with the genotype of patient. Genetics of HBGA secretion, particularly, basis of Leb expression manifested by fucosyltransferase-2 enzyme was studied in healthy individuals and was compared in cases of rotavirus positive and negative diarrhea. Positive clinical isolates with various genotypes were purified from stool samples and gene for VP4 - surface spike protein was sequenced. Using Bioinformatics interphase, three dimensional protein structures were modeled and their functional domains were analyzed. All these modeled proteins were docked with Leb HBGA (Lewis-b Histo Blood Group Antigens using molecular docking software. In present study, to investigate possible association of the rotavirus with host genome, we screened highly suspected genes involved in expression of glycoproteins on enterocytes. This study performed for prevalent Indian strains of rotaviruses provides possible evidence that, VP8 domain of VP4 spike protein utilizes Leb surface antigen for attachment and entry to enterocytes in the intestine. The FUT2 and FUT3 gene has been found to show significant association with the rotavirus infection hence can serve as a biomarker for genetic

Effectiveness and impact of rotavirus vaccines in Europe, 2006-2014.

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Karafillakis, Emilie; Hassounah, Sondus; Atchison, Christina

2015-04-27

Prior to the introduction of rotavirus vaccines in 2006, rotavirus was the leading cause of severe gastroenteritis among European children rotavirus vaccines in Europe following the first eight years of routine use. Four publication databases were searched, yielding 276 unique citations from February 1st, 2006 to July 31st, 2014. Twenty four studies on effectiveness (n=9) and impact (n=15) met the inclusion criteria. Across Europe, vaccine effectiveness against rotavirus-related healthcare utilisation ranged from 68% to 98%, consistent with efficacy data from clinical trials. Reductions in rotavirus hospitalisations ranged from 65% to 84%, consistent with findings from post-marketing studies from the US and Latin America. We confirm the significant public health benefit of rotavirus vaccination in Europe and provide further evidence to support implementation of universal rotavirus vaccination in all European countries. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Analysis of complete genome sequences of G9P[19] rotavirus strains from human and piglet with diarrhea provides evidence for whole-genome interspecies transmission of nonreassorted porcine rotavirus.

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Yodmeeklin, Arpaporn; Khamrin, Pattara; Chuchaona, Watchaporn; Kumthip, Kattareeya; Kongkaew, Aphisek; Vachirachewin, Ratchaya; Okitsu, Shoko; Ushijima, Hiroshi; Maneekarn, Niwat

2017-01-01

Whole genomes of G9P[19] human (RVA/Human-wt/THA/CMH-S070-13/2013/G9P[19]) and porcine (RVA/Pig-wt/THA/CMP-015-12/2012/G9P[19]) rotaviruses concurrently detected in the same geographical area in northern Thailand were sequenced and analyzed for their genetic relationships using bioinformatic tools. The complete genome sequence of human rotavirus RVA/Human-wt/THA/CMH-S070-13/2013/G9P[19] was most closely related to those of porcine rotavirus RVA/Pig-wt/THA/CMP-015-12/2012/G9P[19] and to those of porcine-like human and porcine rotaviruses reference strains than to those of human rotavirus reference strains. The genotype constellation of G9P[19] detected in human and piglet were identical and displayed as the G9-P[19]-I5-R1-C1-M1-A8-N1-T1-E1-H1 genotypes with the nucleotide sequence identities of VP7, VP4, VP6, VP1, VP2, VP3, NSP1, NSP2, NSP3, NSP4, and NSP5 at 99.0%, 99.5%, 93.2%, 97.7%, 97.7%, 85.6%, 89.5%, 93.2%, 92.9%, 94.0%, and 98.1%, respectively. The findings indicate that human rotavirus strain RVA/Human-wt/THA/CMH-S070-13/2013/G9P[19] containing the genome segments of porcine genetic backbone is most likely a human rotavirus of porcine origin. Our data provide an evidence of interspecies transmission and whole-genome transmission of nonreassorted G9P[19] porcine RVA to human occurring in nature in northern Thailand. Copyright © 2016. Published by Elsevier B.V.

Effectiveness of rotavirus vaccines against hospitalisations in Japan.

Science.gov (United States)

Fujii, Yoshiyuki; Noguchi, Atsuko; Miura, Shinobu; Ishii, Haruka; Nakagomi, Toyoko; Nakagomi, Osamu; Takahashi, Tsutomu

2017-07-11

In Japan, rotavirus hospitalisation occurs at a rate from 2.8 to 13.7 per 1000 child-years among children age less than 5 years, and it imposes a substantial burden to the healthcare system in the country. While both monovalent (RV1) and pentavalent (RV5) rotavirus vaccines are licensed in Japan, neither has been incorporated in the national infant immunization programme. In this study, we estimated vaccine effectiveness (VE) in Japan. This study was conducted in Yuri-Kumiai General Hospital located in a city in the north-western part of Japan. Age-eligible children for rotavirus vaccination were enrolled if they were hospitalized for rotavirus gastroenteritis between September 2013 and August 2016. Rotavirus gastroenteritis was defined by the detection of rotavirus antigen by immunochromatography. "Vaccinated" was defined as infant inoculated with at least one dose of either RV1 or RV5. A conditional logistic regression analysis was performed by modelling the year of birth, year of admission, residence of the children and vaccination status, and by matching the age of cases with that of test-negative controls. The adjusted odds ratio of the vaccinated over unvaccinated was then used to calculate VE in the formula of (1 - adjusted odds ratio) × 100. Out of the 244 patients enrolled, rotavirus antigen was detected in 55 (22.5%) of whom 10 (18.2%) were vaccinated, whereas 94 (49.7%) of 189 test-negative controls were vaccinated. During the study period, the vaccine uptake rate in the controls increased from 36.2% to 61.8%. On the other hand, the vaccination coverage over the three years was 64.2% in Yuri-Honjo city (three quarters of the catchment), and 91.4% in Nikaho city (one quarter of the catchment). The VE was calculated to be 70.4% (95% confidence interval: 36.0-86.4%, P = 0.002). The point estimate of the VE was lower but its 95% confidence interval overlaps those of the efficacies obtained from clinical trials in Japan. The rotavirus vaccine was

Estimating the herd immunity effect of rotavirus vaccine.

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Pollard, Suzanne L; Malpica-Llanos, Tanya; Friberg, Ingrid K; Fischer-Walker, Christa; Ashraf, Sania; Walker, Neff

2015-07-31

Diarrhea is one of the leading causes of death in children under 5, and an estimated 39% of these deaths are attributable to rotavirus. Currently two live, oral rotavirus vaccines have been introduced on the market; however, the herd immunity effect associated with rotavirus vaccine has not yet been quantified. The purpose of this meta-analysis was to estimate the herd immunity effects associated with rotavirus vaccines. We performed a systematic literature review of articles published between 2008 and 2014 that measured the impact of rotavirus vaccine on severe gastroenteritis (GE) morbidity or mortality. We assessed the quality of published studies using a standard protocol and conducted meta-analyses to estimate the herd immunity effect in children less than one year of age across all years presented in the studies. We conducted these analyses separately for studies reporting a rotavirus-specific GE outcome and those reporting an all-cause GE outcome. In studies reporting a rotavirus-specific GE outcome, four of five of which were conducted in the United States, the median herd effect across all study years was 22% [19-25%]. In studies reporting an all-cause GE outcome, all of which were conducted in Latin America, the median herd effect was 24.9% [11-30%]. There is evidence that rotavirus vaccination confers a herd immunity effect in children under one year of age in the United States and Latin American countries. Given the high variability in vaccine efficacy across regions, more studies are needed to better examine herd immunity effects in high mortality regions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

PREPARATION OF WC-Co POWDER BY DIRECT REDUCTION AND CARBONIZATION

Institute of Scientific and Technical Information of China (English)

Zhonglai Yi; Gangqin Shao; Xinglong Duan; Peng Sun; Xiaoliang Shi; Zhen Xiong; Jingkun Guo

2005-01-01

A new approach to produce superfine WC-Co powder by direct reduction and carbonization is proposed.Water-soluble salts containing W and Co were used as raw materials. Tungsten and cobalt oxide powder (CoWO4/WO3)was first formed by a spray-pyrolysis technique, which was then mixed with carbon black and converted to WC-Co composite powder at 950℃ for 4 h in N2 atmosphere. The resulting powder has a particle size of 100-300 nm.

Intercontinental circulation of human influenza A(H1N2) reassortant viruses during the 2001-2002 influenza season.

Science.gov (United States)

Xu, Xiyan; Smith, Catherine B; Mungall, Bruce A; Lindstrom, Stephen E; Hall, Henrietta E; Subbarao, Kanta; Cox, Nancy J; Klimov, Alexander

2002-11-15

Reassortant influenza A viruses bearing the H1 subtype of hemagglutinin (HA) and the N2 subtype of neuraminidase (NA) were isolated from humans in the United States, Canada, Singapore, Malaysia, India, Oman, Egypt, and several countries in Europe during the 2001-2002 influenza season. The HAs of these H1N2 viruses were similar to that of the A/New Caledonia/20/99(H1N1) vaccine strain both antigenically and genetically, and the NAs were antigenically and genetically related to those of recent human H3N2 reference strains, such as A/Moscow/10/99(H3N2). All 6 internal genes of the H1N2 reassortants examined originated from an H3N2 virus. This article documents the first widespread circulation of H1N2 reassortants on 4 continents. The current influenza vaccine is expected to provide good protection against H1N2 viruses, because it contains the A/New Caledonia/20/99(H1N1) and A/Moscow/10/99(H3N2)-like viruses, which have H1 and N2 antigens that are similar to those of recent H1N2 viruses.

Zooanthroponotic transmission of rotavirus in Haryana State of Northern India.

Science.gov (United States)

Choudhary, P; Minakshi, P; Ranjan, K; Basanti, B

Rotaviruses are the major cause of severe gastroenteritis and mortality in young children and animals. Due to segmented nature of dsRNA genome and wide host range, vast genetic and antigenic diversity exists amongst different isolates of rotaviruses. A total of 230 fecal ovine and caprine samples collected from organized farms and villages in Haryana were screened for rotavirus detection. Samples were screened by latex agglutination test and RNA-PAGE followed by RT-PCR and nucleic acid sequencing. The latex agglutination test showed 25 newborn lamb and 4 kid fecal samples positive for rotavirus. However, RNA-PAGE showed only 9 lamb fecal samples positive for rotavirus. All the samples were subjected to RT-PCR employing vp4 and vp7 gene specific primers of group A rotavirus of ovine, bovine and human origin. Only two samples from lamb (Sheep18/Hisar/2013 and Sheep22/Hisar/2013) showed vp4 and vp7 gene specific amplification with human group A rotavirus (GAR) specific primer. However, they did not show any amplification with ovine and bovine rotavirus specific primers. The nucleotide as well as deduced amino acid sequence analysis of vp4 gene of these isolates showed >98/97% and vp7 gene >95/94% nt/aa identity with human GAR from different regions of the world. Based on nucleotide similarity search, Sheep18/Hisar/2013 and Sheep22/Hisar/2013 isolates were genotyped as G1P[8] and G1P[4]. Phylogenetic analysis also confirmed that these isolates were clustered closely with human rotaviruses from different regions of the world. Earlier, higher prevalence of human rotaviruses was reported from the sample collecting area. The amplification of ovine samples with human rotavirus gene specific primers, sequence identity and phylogenetic analysis strongly suggests the zoonotic transmission of human GAR to sheep.

Rotavirus Vaccines: a story of success with challenges ahead

Science.gov (United States)

O’Ryan, Miguel

2017-01-01

Approximately 40 years have passed since the discovery of the rotavirus and 10 years since the introduction and progressive dissemination of rotavirus vaccines worldwide. Currently, 92 countries have introduced rotavirus vaccines into national or subnational programs with evident impact in disease reduction. Two vaccines have been widely used, and four additional vaccines have been licensed and are being used in defined regions. In this context, one main issue that remains unsolved is the lower vaccine efficacy/effectiveness in low-income countries. An additional partially answered issue relates to rotavirus strain circulation in vaccinated populations. These issues are discussed in this review. The most imperative challenge ahead is to fulfill the WHO’s recommendation to introduce rotavirus vaccines in all countries. PMID:28928954

Rotaviruses

Centers for Disease Control (CDC) Podcasts

2009-01-06

CDC's Dr. Jon Gentsch discusses rotaviruses, the most important cause of severe gastroenteritis in children less than five years of age. Essentially, all children around the world get the disease during the first few years of life.  Created: 1/6/2009 by Emerging Infectious Diseases.   Date Released: 1/6/2009.

Theoretical studies on the electronic and optoelectronic properties of [A.2AP(w)/A*.2AP(WC)/C.2AP(w)/C*.2AP(WC)/C.A(w)/C*.A(WC)]-Au8 mismatch nucleobase complexes

Science.gov (United States)

Srivastava, Ruby

2018-01-01

The electronic and optoelectronic properties of [A.2AP(w)/A*.2AP(WC)/C.2AP(w)/C*.2AP(WC)/C.A(w)/ C*.A(WC)]-Au8 metal-mismatch nucleobase complexes are investigated by means of density functional theory and time-dependent methods. We selected these mispairs as 2-aminopurine (2AP) produces incorporation errors when binding with cytosine (C) into the wobble (w) C.2AP(w) mispair, and is tautomerised into Watson-Crick (WC)-like base mispair C*.2AP(WC) and less effectively produces A.2AP(w)/A*.2AP(WC) mispairs. The vertical ionisation potential, vertical electron affinity, hardness and electrophilicity index of these complexes have also been discussed. The modifications of energy levels and charge density distributions of the frontier orbitals are also analysed. The absorption spectra of these complexes lie in the visible region, which suggests their application in fluorescent-bio imaging. The mechanism of cooperativity effect is studied by molecular orbital potential (MEP), atoms-in-molecules (AIM) and natural bond orbital analyses. Most metalated pairs have smaller HOMO-LUMO band gaps than the isolated mismatch nucleobases which suggest interesting consequences for electron transfer through DNA duplexes.

Investigations of mussel-inspired polydopamine deposition on WC and Al{sub 2}O{sub 3} particles: The influence of particle size and material

Energy Technology Data Exchange (ETDEWEB)

Mondin, Giovanni, E-mail: giovanni.mondin@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Haft, Marcel, E-mail: m.haft@ifw-dresden.de [Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Institute for Solid State Research, Helmholtzstr. 20, 01069 Dresden (Germany); Wisser, Florian M., E-mail: florian.wisser@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Leifert, Annika, E-mail: annika.leifert@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Mohamed-Noriega, Nasser, E-mail: nasser.mohamed-noriega@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Dörfler, Susanne, E-mail: susanne.doerfler@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Hampel, Silke, E-mail: s.hampel@ifw-dresden.de [Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Institute for Solid State Research, Helmholtzstr. 20, 01069 Dresden (Germany); Grothe, Julia, E-mail: stefan.kaskel@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany); Kaskel, Stefan, E-mail: julia.grothe@chemie.tu-dresden.de [Department of Inorganic Chemistry, Dresden University of Technology, Bergstrasse 66, 01069 Dresden (Germany)

2014-12-15

Polydopamine, formed by oxidation of dopamine, is a bioinspired polymer developed for multifunctional coatings by Lee et al. in 2007 by drawing inspiration from the adhesive proteins found in mussels. Due to their high versatility and substrate-independence, polydopamine coatings are gaining considerable attention in a plethora of research fields, particularly in the coating of particles, but systematic investigations of the polydopamine coating process are lacking in the literature. In this study, we explore by TEM and thermogravimetric analysis the polydopamine coating process on alumina microparticles, tungsten carbide microparticles and tungsten carbide nanoparticles. By choosing two substrates with similar size but different material (Al{sub 2}O{sub 3} and WC), as well as two substrates of the same material but different size (WC micro- and nanoparticles) we investigate the effects of both substrate material and substrate size, in order to gain some insights into the polydopamine particle coating process. As opposed to what is generally assumed in the literature, we found that the polydopamine coating thicknesses on particles, as well as the thickness growing trend, depend on the particles size and material. In particular, after 24 h of polymerization time the polydopamine coatings reached a thickness of 65 ± 10 nm in the case of Al{sub 2}O{sub 3} microparticles, 18 ± 4 nm in the case of WC microparticles and 33 ± 6 nm in the case of WC nanoparticles. - Highlights: • The coating of different particles with polydopamine was systematically investigated. • Al{sub 2}O{sub 3} microparticles and WC microparticles and nanoparticles were investigated. • The thickness of the polydopamine coating depends on the particle size. • The thickness of the polydopamine coating depends on the particle material.

New tetrameric forms of the rotavirus NSP4 with antiparallel helices.

Science.gov (United States)

Kumar, Sushant; Ramappa, Raghavendra; Pamidimukkala, Kiranmayee; Rao, C D; Suguna, K

2018-06-01

Rotavirus nonstructural protein 4, the first viral enterotoxin to be identified, is a multidomain, multifunctional glycoprotein. Earlier, we reported a Ca 2+ -bound coiled-coil tetrameric structure of the diarrhea-inducing region of NSP4 from the rotavirus strains SA11 and I321 and a Ca 2+ -free pentameric structure from the rotavirus strain ST3, all with a parallel arrangement of α-helices. pH was found to determine the oligomeric state: a basic pH favoured a tetramer, whereas an acidic pH favoured a pentamer. Here, we report two novel forms of the coiled-coil region of NSP4 from the bovine rotavirus strains MF66 and NCDV. These crystallized at acidic pH, forming antiparallel coiled-coil tetrameric structures without any bound Ca 2+ ion. Structural and mutational studies of the coiled-coil regions of NSP4 revealed that the nature of the residue at position 131 (Tyr/His) plays an important role in the observed structural diversity.

Reassortant swine influenza viruses isolated in Japan contain genes from pandemic A(H1N1) 2009.

Science.gov (United States)

Kanehira, Katsushi; Takemae, Nobuhiro; Uchida, Yuko; Hikono, Hirokazu; Saito, Takehiko

2014-06-01

In 2013, three reassortant swine influenza viruses (SIVs)-two H1N2 and one H3N2-were isolated from symptomatic pigs in Japan; each contained genes from the pandemic A(H1N1) 2009 virus and endemic SIVs. Phylogenetic analysis revealed that the two H1N2 viruses, A/swine/Gunma/1/2013 and A/swine/Ibaraki/1/2013, were reassortants that contain genes from the following three distinct lineages: (i) H1 and nucleoprotein (NP) genes derived from a classical swine H1 HA lineage uniquely circulating among Japanese SIVs; (ii) neuraminidase (NA) genes from human-like H1N2 swine viruses; and (iii) other genes from pandemic A(H1N1) 2009 viruses. The H3N2 virus, A/swine/Miyazaki/2/2013, comprised genes from two sources: (i) hemagglutinin (HA) and NA genes derived from human and human-like H3N2 swine viruses and (ii) other genes from pandemic A(H1N1) 2009 viruses. Phylogenetic analysis also indicated that each of the reassortants may have arisen independently in Japanese pigs. A/swine/Miyazaki/2/2013 were found to have strong antigenic reactivities with antisera generated for some seasonal human-lineage viruses isolated during or before 2003, whereas A/swine/Miyazaki/2/2013 reactivities with antisera against viruses isolated after 2004 were clearly weaker. In addition, antisera against some strains of seasonal human-lineage H1 viruses did not react with either A/swine/Gunma/1/2013 or A/swine/Ibaraki/1/2013. These findings indicate that emergence and spread of these reassortant SIVs is a potential public health risk. © 2014 The Societies and Wiley Publishing Asia Pty Ltd.

Effectiveness of pentavalent rotavirus vaccine in a large urban population in the United States.

Science.gov (United States)

Boom, Julie A; Tate, Jacqueline E; Sahni, Leila C; Rench, Marcia A; Hull, Jennifer J; Gentsch, Jon R; Patel, Manish M; Baker, Carol J; Parashar, Umesh D

2010-02-01

The goal was to assess the effectiveness of complete (3-dose) or partial (1- or 2-dose) immunization with pentavalent rotavirus vaccine (RV5) against rotavirus acute gastroenteritis (AGE) in US clinical practice. A case-control evaluation was conducted in February through June 2008 at an emergency department in Houston, Texas. Case patients with rotavirus AGE (N = 90) were identified through testing for rotavirus in fecal specimens obtained from 205 children 15 days through 23 months of age presenting with AGE. Control groups included rotavirus-negative AGE patients (N = 115), concurrently enrolled patients with acute respiratory infection (ARI) (N = 228), and up to 10 age- and zip code-matched children sampled from the Houston-Harris County Immunization Registry (HHCIR) for each case patient >8 months of age. Immunization data were obtained from parent records, health care providers, and/or the HHCIR. Vaccine effectiveness was calculated as 1 minus odds of RV5 vaccination for case patients versus control patients, after adjustment for age at presentation and birth date. The vaccine effectiveness of a complete RV5 series was 89% (95% confidence interval [CI]: 70%-96%) and 85% (95% CI: 55%-95%) with rotavirus-negative AGE and ARI control patients, respectively. Immunization data were available for 44% of case patients (n = 40) from the HHCIR; the estimated 3-dose vaccine effectiveness with these HHCIR control patients was 82% (95% CI: 19%-96%). A complete RV5 series conferred 100% protection (95% CI: 71%-100%) against severe rotavirus disease requiring hospitalization and 96% protection (95% CI: 72%-99%) against disease requiring intravenous hydration. Vaccine effectiveness of 1 and 2 doses against hospitalization and emergency department visits was 69% (95% CI: 13%-89%) and 81% (95% CI: 13%-96%), respectively, using rotavirus-negative AGE and ARI control groups combined. In this setting, a complete series of RV5 was highly effective against severe rotavirus AGE

Benzotriazole (BTA), A Promising Corrosion Inhibitor for WC-Co Hardmetal

Energy Technology Data Exchange (ETDEWEB)

Schnyder, B.; Stoessel-Sittig, C.; Koetz, R.; Hochstrasser-Kurz, S. [ETH Zuerich (Switzerland); Virtanen, S. [ETH Zuerich (Switzerland); Jaeggi, Ch. [University of Bern (Switzerland); Eichenberger, N. [University of Bern (Switzerland); Szoecs, E. [University of Bern (Switzerland); Siegenthaler, H. [University of Bern (Switzerland); Ziegler, P. [AGIE SA (Switzerland); Beltrami, I. [AGIE SA (Switzerland)

2004-03-01

Wire Electro-Discharge Machining (W-EDM) of tungsten carbide with Co-binder may lead to corrosion and discolouration at the surface. The corrosion behaviour of WC-Co based hardmetal was investigated in different aqueous solutions (acidic, neutral, and alkaline solutions). At open-circuit potential WC-Co based hardmetals show rather high dissolution rates in all types of electrolyte. An efficient corrosion inhibitor (benzotriazole, C{sub 6}H{sub 5}N{sub 3}) could be found for a borate buffer solution, pH = 8.4. (author)

Reduction in Rotavirus-associated Acute Gastroenteritis Following Introduction of Rotavirus Vaccine Into Australia's National Childhood Vaccine Schedule

NARCIS (Netherlands)

Buttery, Jim P.; Lambert, Stephen B.; Grimwood, Keith; Nissen, Michael D.; Field, Emma J.; Macartney, Kristine K.; Akikusa, Jonathan D.; Kelly, Julian J.; Kirkwood, Carl D.

Introduction: Rotavirus vaccines were introduced into the funded Australian National Immunization Program (NIP) in July 2007. Due to purchasing arrangements, individual states and territories chose either a 2-dose RV1 (Rotarix, GSK) regimen or 3-dose RV5 (Rotateq, Merck/CSL) regimen. This allowed

SHIFT IN HUMAN ROTAVIRUS DISTRIBUTION IN BELO HORIZONTE, BRAZIL DETECTED BY RIBONUCLEIC ACID ELECTROPHORESIS

Directory of Open Access Journals (Sweden)

Millan Scarabeli Alves Coelho da Silva

2013-04-01

Full Text Available Rotavirus has been considered the main agent of infectious diarrhea especially among younger children. We addressed the prevalence of rotavirus-associated diarrhea and the diversity of circulating electropherotypes by immunochromatography and RNA electrophoresis. Stool samples were taken from 391 children (267 with diarrhea from the lower socioeconomic stratum who sought treatment in the Hospital Infantil João Paulo II/Belo Horizonte, during 2005 and 2006. Rotavirus was detected in 79/20.2% of subjects, 64/24.0% with diarrhea and 15/12.1% with no diarrhea. The virus was strongly associated with diarrhea (p = 0.003. A total of 76/19.4% and 69/17.6% rotavirus-positive children were identified by immunochromatography and electrophoresis, respectively. Rotavirus-associated diarrhea was more frequently detected in dry months (p < 0.001 and almost exclusively in children aged up to three years. Long profile strains prevailed (54/78.3% but a shift toward short electropherotype was identified. Despite the decrease seen in 2006, rotavirus infection is still very common in our area. Although viral RNA electrophoresis is useful as a typing method, it should not be used exclusively in the diagnosis of rotavirus infection. We confirmed a shift from long to short profile strains, as already described for other South American countries.

Rotavirus diarrhea disease burden in Peru: the need for a rotavirus vaccine and its potential cost savings Carga de morbilidad de la diarrea por rotavirus en Perú: la necesidad de una vacuna y su potencial de ahorro

Directory of Open Access Journals (Sweden)

Peter Ehrenkranz

2001-10-01

Full Text Available Objective. To assess the disease burden of rotavirus diarrhea in Peru as well the need for and the potential cost savings with a rotavirus vaccine in that country. Methods. To assess the burden of rotavirus diarrhea in Peru, we reviewed published and unpublished reports where rotavirus was sought as the etiologic agent of diarrhea in children. Rotavirus detection rates obtained from these studies were combined with diarrhea incidence rates from a number of national surveys in order to estimate both the burden of rotavirus diarrhea in the country and its associated medical costs. Results. Rotavirus is a significant cause of morbidity and mortality in Peruvian children. In their first 5 years of life, an estimated 1 in 1.6 children will experience an episode of rotavirus diarrhea, 1 in 9.4 will seek medical care, 1 in 19.7 will require hospitalization, and 1 in 375 will die of the disease. Per year, this represents approximately 384 000 cases, 64 000 clinic visits, 30 000 hospitalizations, and 1 600 deaths. The annual cost of medical care alone for these children is approximately US$ 2.6 million--and that does not take into account the indirect or societal costs of the illness and the deaths. Conclusions. Rotavirus immunization provides the prospect of decreasing the morbidity and mortality from diarrhea in Peru, but a vaccine regimen would have to be relatively inexpensive, a few dollars or less per child. Future cost-effectiveness analyses should explore the total costs (medical as well as indirect or societal associated with rotavirus diarrhea. Newly licensed vaccines should be tested according to both their ability to avert deaths and their efficacy with fewer than three doses. All three of these factors could increase the cost savings associated with a rotavirus vaccine.Objetivos. Evaluar la carga de morbilidad de la diarrea por rotavirus en Perú, la necesidad de una vacuna y el ahorro que esta podría proporcionar en este país. M�

Group A Rotavirus Associated with Encephalitis in Red Fox.

Science.gov (United States)

Busi, Chiara; Martella, Vito; Papetti, Alice; Sabelli, Cristiano; Lelli, Davide; Alborali, G Loris; Gibelli, Lucia; Gelmetti, Daniela; Lavazza, Antonio; Cordioli, Paolo; Boniotti, M Beatrice

2017-09-01

In 2011, a group A rotavirus was isolated from the brain of a fox with encephalitis and neurologic signs, detected by rabies surveillance in Italy. Intracerebral inoculation of fox brain homogenates into mice was fatal. Genome sequencing revealed a heterologous rotavirus of avian origin, which could provide a model for investigating rotavirus neurovirulence.

Atomic layer deposition synthesis and evaluation of core–shell Pt-WC electrocatalysts

International Nuclear Information System (INIS)

Hsu, Irene J.; Chen, Jingguang G.; Jiang, Xiaoqiang; Willis, Brian G.

2015-01-01

Pt-WC core shell particles were produced using atomic layer deposition (ALD) to deposit Pt layers onto WC particle substrates. A range of Pt depositions were used to determine the growth mechanism for the Pt-WC powder system. TEM imaging and Cu stripping voltammetry found that Pt ALD growth on WC powder substrates was similar to that on WC thin films. However, excess free carbon was found to affect Pt ALD by blocking adsorption sites on WC. The Pt-WC samples were evaluated for the oxygen reduction reaction using a rotating disk electrode to obtain quantitative activity information. The mass and specific activities for the 30 and 50 ALD cycle samples were found to be comparable to a 10 wt. % Pt/C catalyst. However, higher overpotentials and lower limiting currents were observed with ALD Pt-WC compared to Pt/C catalysts, indicating that the oxygen reduction mechanism is not as efficient on Pt-WC as on bulk Pt. Additionally, these Pt-WC catalysts were used to demonstrate hydrogen evolution reaction activity and were found to perform as well as bulk Pt catalyst but with a fraction of the Pt loading, in agreement with the previous work on Pt-WC thin film catalysts

Erosion-oxidation behavior of thermal sprayed Ni20Cr alloy and WC and Cr3C2 cermet coatings

Directory of Open Access Journals (Sweden)

Clarice Terui Kunioshi

2005-06-01

Full Text Available An apparatus to conduct high temperature erosion-oxidation studies up to 850 °C and with particle impact velocities up to 15 m.s-1 was designed and constructed in the Corrosion Laboratories of IPEN. The erosion-oxidation behavior of high velocity oxy fuel (HVOF sprayed alloy and cermet coatings of Ni20Cr, WC 20Cr7Ni and Cr3C2 Ni20Cr on a steel substrate has been studied. Details of this apparatus and the erosion-oxidation behavior of these coatings are presented and discussed. The erosion-oxidation behavior of HVOF coated Cr3C2 25(Ni20Cr was better than that of WC 20Cr7Ni, and the erosion-oxidation regimes have been identified for these coatings at particle impact velocity of 3.5 m.s-1, impact angle of 90° and temperatures in the range 500 to 850 °C.

[Seasonality of rotavirus infection in Venezuela: relationship between monthly rotavirus incidence and rainfall rates].

Science.gov (United States)

González Chávez, Rosabel

2015-09-01

In general, it has been reported that rotavirus infection was detected year round in tropical countries. However, studies in Venezuela and Brazil suggest a seasonal behavior of the infection. On the other hand, some studies link infection with climatic variables such as rainfall. This study analyzes the pattern of behavior of the rotavirus infection in Carabobo-Venezuela (2001-2005), associates the seasonality of the infection with rainfall, and according to the seasonal pattern, estimates the age of greatest risk for infection. The analysis of the rotavirus temporal series and accumulated precipitation was performed with the software SPSS. The infection showed two periods: high incidence (November-April) and low incidence (May-October). Accumulated precipitation presents an opposite behavior. The highest frequency of events (73.8% 573/779) for those born in the period with a low incidence of the virus was recorded at an earlier age (mean age 6.5 +/- 2.0 months) when compared with those born in the station of high incidence (63.5% 568/870, mean age 11.7 +/- 2.2 months). Seasonality of the infection and the inverse relationship between virus incidence and rainfall was demonstrated. In addition, it was found that the period of birth determines the age and risk of infection. This information generated during the preaccine period will be helpful to measure the impact of the vaccine against the rotavirus.

Genetic Diversity of Circulating Rotavirus Strains in Tanzania Prior to the Introduction of Vaccination

Science.gov (United States)

Moyo, Sabrina J.; Blomberg, Bjørn; Hanevik, Kurt; Kommedal, Oyvind; Vainio, Kirsti; Maselle, Samuel Y.; Langeland, Nina

2014-01-01

Background Tanzania currently rolls out vaccination against rotavirus-diarrhea, a major cause of child illness and death. As the vaccine covers a limited number of rotavirus variants, this study describes the molecular epidemiology of rotavirus among children under two years in Dar es Salaam, Tanzania, prior to implementation of vaccination. Methods Stool specimens, demographic and clinical information, were collected from 690 children admitted to hospital due to diarrhea (cases) and 545 children without diarrhea (controls) during one year. Controls were inpatient or children attending child health clinics. Rotavirus antigen was detected using ELISA and positive samples were typed by multiplex semi-nested PCR and sequencing. Results The prevalence of rotavirus was higher in cases (32.5%) than in controls (7.7%, Protavirus prevalence was higher in cool (23.9%) than hot months (17.1%) of the year (P = 0.012). We also observed significant seasonal variation of G genotypes. Rotavirus was most frequently found in the age group of four to six months. The prevalence of rotavirus in cases was lower in stunted children (28.9%) than in non-stunted children (40.1%, P = 0.003) and lower in HIV-infected (15.4%, 4/26) than in HIV-uninfected children (55.3%, 42/76, PRotavirus infection and circulating genotypes showed seasonal variation. This study also suggests that rotavirus may not be an opportunistic pathogen in children infected with HIV. PMID:24844631

75 FR 48706 - Proposed Vaccine Information Materials for Rotavirus Vaccine

Science.gov (United States)

2010-08-11

... Vaccine Information Materials for Rotavirus Vaccine AGENCY: Centers for Disease Control and Prevention... information materials for rotavirus vaccine. DATES: Written comments are invited and must be received on or... (chickenpox), pneumococcal conjugate, rotavirus, hepatitis A, meningococcal, human papillomavirus (HPV), and...

Catalytic activity of tungsten carbide-carbon (WC@C) core-shell structured for ethanol electro-oxidation

Energy Technology Data Exchange (ETDEWEB)

Singla, Gourav, E-mail: gsinghla@gmail.com; Singh, K., E-mail: kusingh@thapar.edu; Pandey, O.P., E-mail: oppandey@thapar.edu

2017-01-15

In this study, carbon coated WC (WC@C) was synthesized through solvothermal reactions in the presence of reducing agent magnesium (Mg) by employing tungsten oxide (WO{sub 3}) as a precursor, acetone (C{sub 3}H{sub 6}O) as a carbon source. The formation of WC@C nano particles is confirmed by X-ray diffraction and Transmission electron microscopy. The thermal stability of the synthesized powder examined in air shows its stability up to 550 °C. In this method, in-situ produced outer carbon layer increase the surface area of materials which is 52.6 m{sup 2} g{sup −1} with pore volume 0.213 cm{sup 3} g{sup −1}. The Electrocatalytic activity of ethanol oxidation on a synthesized sample with and without Pt nano particles have been investigated using cyclic voltammetry (CV). The CV results show the enhancement in oxidation stability of WC@C in acidic media as well as better CO-tolerance for ethanol oxidation after the deposition of Pt nanoparticles as compared to without Pt nano particles. - Highlights: • Tungsten carbide nano powder was synthesized using acetone as carbon source. • In-situ produced outer carbon layer increase the surface area of materials. • Mesoporous WC with surface areas 52.6 m{sup 2}/g obtained. • Pt modified WC powder showed higher electrochemical stability. • Better CO-tolerance for ethanol oxidation after the deposition of Pt nanoparticles.

Physical properties and microstructure of Ti(CN)-based cermets with different WC particle size

International Nuclear Information System (INIS)

Deng, Ying; Deng, Ling; Xiong, Xiang; Ye, J.W.; Li, P.P.

2014-01-01

Ti(CN)-based cermets with different WC particle sizes from 0.2 to 4 μm were prepared at 1450 °C with 2 MPa Air pressure. The microstructure of cermets was investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), Transmission electron microscope (TEM). The results showed that all the cermets with different WC particle sizes have a typical “core–rim” structure. With the increase of WC powder sizes, the frequency and portion of Ti(C 0.7 N 0.3 ) cores and rim are somewhat decreased while the portion of white core is increased, due to the relative dissolution rate decreasing. In addition, the fracture mode of Ti(C,N) based cermets is a mixture of trans-granular (primary) and inter-granular (subordinate) fracture. The TRS (about 1850 MPa) of the cermets fluctuate slightly with the WC particle sizes from 0.2 to 1.0 μm, but decrease evidently with WC particle sizes up to 2 μm

Burden of paediatric Rotavirus Gastroenteritis (RVGE and potential benefits of a universal Rotavirus vaccination programme with a pentavalent vaccine in Spain

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Diez-Domingo Javier

2010-08-01

Full Text Available Abstract Background Rotavirus is the most common cause of gastroenteritis in young children worldwide. The aim of the study was to assess the health outcomes and the economic impact of a universal rotavirus vaccination programme with RotaTeq, the pentavalent rotavirus vaccine, versus no vaccination programme in Spain. Methods A birth cohort was followed up to the age of 5 using a cohort model. Epidemiological parameters were taken from the REVEAL study (a prospective epidemiological study conducted in Spain, 2004-2005 and from the literature. Direct and indirect costs were assessed from the national healthcare payer and societal perspectives by combining health care resource utilisation collected in REVEAL study and unit costs from official sources. RotaTeq per protocol efficacy data was taken from a large worldwide rotavirus clinical trial (70,000 children. Health outcomes included home care cases, General Practioner (GP/Paediatrician, emergency department visits, hospitalisations and nosocomial infections. Results The model estimates that the introduction of a universal rotavirus vaccination programme with RotaTeq (90% coverage rate would reduce the rotavirus gastroenteritis (RVGE burden by 75% in Spain; 53,692 home care cases, 35,187 GP/Paediatrician visits, 34,287 emergency department visits, 10,987 hospitalisations and 2,053 nosocomial infections would be avoided. The introduction of RotaTeq would avoid about 76% of RVGE-related costs from both perspectives: €22 million from the national health system perspective and €38 million from the societal perspective. Conclusions A rotavirus vaccination programme with RotaTeq would reduce significantly the important medical and economic burden of RVGE in Spain.

Surface analysis of WC--Co composite materials (2) Quantitative Auger electron spectrometry

International Nuclear Information System (INIS)

Tongson, L.L.; Biggers, J.V.; Dayton, G.O.; Bind, J.M.; Knox, B.E.

1978-01-01

The unique sensitivity of Auger electron spectrometry (AES) to combined carbon has been exploited in measuring the surface compositions of hot-pressed, conventionally sintered and mixed powders of WC--Co composite materials. AES sensitivity factors for tungsten and carbon (in WC) relative to cobalt were determined. The concentrations of the major elements in hot-pressed samples measured with AES using the relative sensitivity method were compared to those obtained independently by electron microprobe (EMP) and x-ray fluorescence (XRF) techniques. Corollary studies using ion scattering spectrometry (ISS) showed the absence of (1) matrix effects in the AES measurements, (2) preferential sputtering during ion bombardment, and (3) deposition of the easier-to-sputter component (cobalt) onto WC

Projecting the effectiveness of RotaTeq® against rotavirus-related hospitalisations in Brazil

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Antoine Chaouki El Khoury

2011-08-01

Full Text Available RotaTeq® (Merck & Company, Inc, Whitehouse Station, NJ, USA is an oral pentavalent rotavirus vaccine (RV5 that has shown high and consistent efficacy in preventing rotavirus gastroenteritis (RGE in randomised clinical trials previously conducted in industrialised countries with high medical care resources. To date, the efficacy and effectiveness data for RV5 are available in some Latin American countries, but not Brazil. In this analysis, we projected the effectiveness of RV5 in terms of the percentage reduction in RGE-related hospitalisations among children less than five years of age in four regions of Brazil, using a previously validated mathematical model. The model inputs included hospital-based rotavirus surveillance data from Goiânia, Porto Alegre, Salvador and São Paulo from 2005-2006, which provided the proportions of rotavirus attributable to serotypes G1, G2, G3, G4 and G9, and published rotavirus serotype-specific efficacy from the Rotavirus Efficacy and Safety Trial. The model projected an overall percentage reduction of 93% in RGE-related hospitalisations, with an estimated annual reduction in RGE-related hospitalisations between 42,991-77,383 in the four combined regions of Brazil. These results suggest that RV5 could substantially prevent RGE-related hospitalisations in Brazil.

Options for improving effectiveness of rotavirus vaccines in developing countries.

Science.gov (United States)

Tissera, Marion S; Cowley, Daniel; Bogdanovic-Sakran, Nada; Hutton, Melanie L; Lyras, Dena; Kirkwood, Carl D; Buttery, Jim P

2017-04-03

Rotavirus gastroenteritis is a leading global cause of mortality and morbidity in young children due to diarrhea and dehydration. Over 85% of deaths occur in developing countries. In industrialised countries, 2 live oral rotavirus vaccines licensed in 2006 quickly demonstrated high effectiveness, dramatically reducing severe rotavirus gastroenteritis admissions in many settings by more than 90%. In contrast, the same vaccines reduced severe rotavirus gastroenteritis by only 30-60% in developing countries, but have been proven life-saving. Bridging this "efficacy gap" offers the possibility to save many more lives of children under the age of 5. The reduced efficacy of rotavirus vaccines in developing settings may be related to differences in transmission dynamics, as well as host luminal, mucosal and immune factors. This review will examine strategies currently under study to target the issue of reduced efficacy and effectiveness of oral rotavirus vaccines in developing settings.

Diarrheal Diseases Hospitalization in Yemen before and after Rotavirus Vaccination

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Mohammed Amood AL-Kamarany

2016-01-01

Full Text Available The study aims to assess the impact of rotavirus vaccine introduction on diarrheal diseases hospitalization and to identify the rotavirus genotypes most prevalent before and after vaccine introduction among children ≤ 5 years of age. Rotarix™ ® rotavirus vaccine is currently licensed for infants in Yemen and was introduced in 2012. The vaccination course consists of two doses. The first dose is administrated at 6 weeks of age and the second dose is completed by 10 weeks. Based on a longitudinal observational study, we assessed the impact of vaccination on rotavirus hospitalization before and after vaccination among children ≤ 5 years of age at the Yemeni-Swedish Hospital (YSH in Taiz, Yemen. Prevaccination covered January 2009–July 2012 during which 2335 fecal samples were collected from children ≤ 5 years old. Postvaccination covered January 2013–December 2014 during which 1114 fecal samples were collected. Rotavirus was detected by Enzyme Linkage Immunosorbent Assay (ELISA. The incidence of rotavirus hospitalization decreased from 43.79% in 2009 to 10.54% in 2014. Hospitalization due to rotavirus diarrhea was reduced by 75.93%. Vaccine coverage increased from 23% in 2012 to 72% in 2014. Also, the results showed that the most predominant genotypes in prevaccination period were G2P[4] (55.0%, followed by G1P[8] (15.0%, while in postvaccination period G1P[8] (31% was the predominant genotype, followed by G9P[8] (27.5%. In conclusion, rotavirus vaccination in Yemen resulted in sharp reduction in diarrheal hospitalization. A successful rotavirus vaccination program in Yemen will rely upon efficient vaccine delivery systems and sustained vaccine efficacy against diverse and evolving rotavirus strains.

Microstructure, Wear Behavior and Corrosion Resistance of WC-FeCrAl and WC-WB-Co Coatings

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Janette Brezinová

2018-05-01

Full Text Available The paper is focused on investigating the quality of two grades of thermally sprayed coatings deposited by high-velocity oxygen fuel (HVOF technology. One grade contains WC hard particles in an environmentally progressive Ni- and Co-free FeCrAl matrix, while the second coating contains WC and WB hard particles in a cobalt matrix. The aim of the experimental work was to determine the effect of thermal cyclic loading on the coatings’ resistance to adhesive, abrasive and erosive wear. Abrasive wear was evaluated using abrasive cloth of two grit sizes, and erosive wear was evaluated by a dry-pot wear test in a pin mill at two sample angles. Adhesion wear resistance of the coatings was determined by a sliding wear test under dry friction conditions and in a 1 mol water solution of NaCl. Corrosion resistance of the coatings was evaluated using potentiodynamic polarization tests. Metallographic cross-sections were used for measurement of the microhardness and thickness and for line energy-dispersive X-ray (EDX analysis. The tests proved the excellent resistance of both coatings against adhesive, abrasive, and erosive wear, as well as the ability of the WC-WB-Co coating to withstand alternating temperatures of up to 600 °C. The “green carbide” coating (WC-FeCrAl can be recommended as an environmentally friendly replacement for Ni- and Co-containing coatings, but its operating temperature is strictly limited to 500 °C in air.

The epidemiology of rotavirus diarrhea in Latin America: anticipating rotavirus vaccines La epidemiología de la diarrea por rotavirus en América Latina: perspectivas de vacunación frente al rotavirus

Directory of Open Access Journals (Sweden)

Erin M. Kane

2004-12-01

Full Text Available OBJECTIVE: To assess the disease burden and characterize the epidemiology of rotavirus diarrhea in Latin America. METHODS: We conducted a literature review of studies of children OBJETIVO: Valorar la carga de enfermedad e identificar las características epidemiológicas de la diarrea causada por rotavirus en América Latina. MÉTODOS: Realizamos una revisión de la literatura que abarcaba los estudios de niños menores de 5 años que fueron hospitalizados o atendidos como pacientes ambulatorios a causa de la diarrea, y en los cuales se buscó al rotavirus como agente etiológico de la diarrea. Nuestro trabajo de revisión incluye los estudios publicados desde el año 1998 sobre pacientes ingresados y ambulatorios, que incluyeron a 100 niños o más, y que informaron sobre actividades de vigilancia que se prolongaron durante al menos 12 meses consecutivos. RESULTADOS: Un total de 18 estudios de pacientes ingresados y 10 estudios de pacientes ambulatorios satisficieron los criterios de inclusión de nuestro trabajo de revisión. Se detectó el rotavirus en el 31% (mediano de los pacientes ingresados (intervalo del 16% al 52% y en el 30.5% de los pacientes ambulatorios (intervalo del 4% al 42%. La tasa mediana de detección fue mayor en los estudios que emplearon un ensayo de encimoinmunoanálisis (ELISA (pacientes ingresados: 38%, pacientes ambulatorios: 33% frente a otros métodos de detección menos sensibles. La distribución de la enfermedad rotavírica según la edad difería entre países, aunque la proporción de niños hospitalizados durante el primer año de vida fue del 65% al 85%. En la mayoría de los países se produjeron ingresos hospitalarios por rotavirus durante todo el año, y el rotavirus normalmente mostraba un máximo estacional en el invierno tanto en las zonas de clima tropical como en aquellas de clima templado. CONCLUSIONES: La importante carga de enfermedad que se atribuye al rotavirus en América Latina sugiere que las

SPREAD AND PRIMARY MANIFESTATIONS OF ROTAVIRUS INFECTION MORBIDITY IN DIFFERENT PARTS OF THE WORLD

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V. V. Kudryavtsev

2013-01-01

Full Text Available The article presents data on the peculiarities of the rotavirus infection spreading in the Russian Federation and other certain countries. It is shown that morbidity levels depend on both objective (population size and territory density, transmission paths activity and subjective (detectability levels factors. It has been established that children 0-3 years of age are the most susceptible to rotavirus infection. The epidemic process development intensity is higher in bigger cities. Considerable regional and seasonal changeability of circulating rotavirus strains is noted.

Novel reassortant of swine influenza H1N2 virus in Germany.

Science.gov (United States)

Zell, Roland; Motzke, Susann; Krumbholz, Andi; Wutzler, Peter; Herwig, Volker; Dürrwald, Ralf

2008-01-01

European porcine H1N2 influenza viruses arose after multiple reassortment steps involving a porcine influenza virus with avian-influenza-like internal segments and human H1N1 and H3N2 viruses in 1994. In Germany, H1N2 swine influenza viruses first appeared in 2000. Two German H1N2 swine influenza virus strains isolated from pigs with clinical symptoms of influenza are described. They were characterized by the neutralization test, haemagglutination inhibition (HI) test and complete sequencing of the viral genomes. The data demonstrate that these viruses represent a novel H1N2 reassortant. The viruses showed limited neutralization by sera raised against heterologous A/sw/Bakum/1,832/00-like H1N2 viruses. Sera pools from recovered pigs showed a considerably lower HI reaction, indicative of diagnostic difficulties in using the HI test to detect these viruses with A/sw/Bakum/1,832/00-like H1N2 antigens. Genome sequencing revealed the novel combination of the human-like HAH1 gene of European porcine H1N2 influenza viruses and the NAN2 gene of European porcine H3N2 viruses.

Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark.

Science.gov (United States)

Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik; Nielsen, Jens; Bøtner, Anette; Heegaard, Peter M H; Fomsgaard, Anders; Viuff, Birgitte; Hjulsager, Charlotte Kristiane

2013-09-18

The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an "avian-like" H1N1 virus by an experimental infection study. Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an "avian-like" H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European "avian-like" H1-gene and a European "swine-like" N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish "avian-like" H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. The "avian-like" H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant between circulating swine "avian-like" H1N1 and H3N2. The Danish

Infectious rotavirus enters cells by direct cell membrane penetration, not by endocytosis

International Nuclear Information System (INIS)

Kaljot, K.T.; Shaw, R.D.; Greenberg, H.B.; Rubin, D.H.

1988-01-01

Rotaviruses are icosahedral viruses with a segmented, double-stranded RNA genome. They are the major cause of severe infantile infectious diarrhea. Rotavirus growth in tissue culture is markedly enhanced by pretreatment of virus with trypsin. Trypsin activation is associated with cleavage of the viral hemagglutinin (viral protein 3 [VP3]; 88 kilodaltons) into two fragments (60 and 28 kilodaltons). The mechanism by which proteolytic cleavage leads to enhanced growth is unknown. To determine whether trypsin treatment affected rotavirus internalization, the authors studied the kinetics of entry of infectious rhesus rotavirus (RRV) into MA104 cells. Trypsin-activated RRV was internalized with a half-time of 3 to 5 min, while nonactivated virus disappeared from the cell surface with a half-time of 30 to 50 min. In contrast to trypsin-activated RRV, loss of nonactivated RRV from the cell surface did not result in the appearance of infection, as measured by plaque formation. Purified trypsin-activated RRV added to cell monolayers at pH 7.4 mediated 51 Cr, [ 14 C]choline, and [ 3 H]inositol released from prelabeled MA104 cells. This release could be specifically blocked by neutralizing antibodies to VP3. These results suggest that MA104 cell infection follows the rapid entry of trypsin-activated RRV by direct cell membrane penetration. Cell membrane penetration of infectious RRV is initiated by trypsin cleavage of VP3. Neutralizing antibodies can inhibit this direct membrane penetration

Infectious rotavirus enters cells by direct cell membrane penetration, not by endocytosis

Energy Technology Data Exchange (ETDEWEB)

Kaljot, K.T.; Shaw, R.D.; Greenberg, H.B. (Stanford Univ. School of Medicine, CA (USA) Palo Alto Veterans Administration Medical Center, CA (USA)); Rubin, D.H. (Univ. of Pennsylvania, Philadelphia (USA))

1988-04-01

Rotaviruses are icosahedral viruses with a segmented, double-stranded RNA genome. They are the major cause of severe infantile infectious diarrhea. Rotavirus growth in tissue culture is markedly enhanced by pretreatment of virus with trypsin. Trypsin activation is associated with cleavage of the viral hemagglutinin (viral protein 3 (VP3); 88 kilodaltons) into two fragments (60 and 28 kilodaltons). The mechanism by which proteolytic cleavage leads to enhanced growth is unknown. To determine whether trypsin treatment affected rotavirus internalization, the authors studied the kinetics of entry of infectious rhesus rotavirus (RRV) into MA104 cells. Trypsin-activated RRV was internalized with a half-time of 3 to 5 min, while nonactivated virus disappeared from the cell surface with a half-time of 30 to 50 min. In contrast to trypsin-activated RRV, loss of nonactivated RRV from the cell surface did not result in the appearance of infection, as measured by plaque formation. Purified trypsin-activated RRV added to cell monolayers at pH 7.4 mediated {sup 51}Cr, ({sup 14}C)choline, and ({sup 3}H)inositol released from prelabeled MA104 cells. This release could be specifically blocked by neutralizing antibodies to VP3. These results suggest that MA104 cell infection follows the rapid entry of trypsin-activated RRV by direct cell membrane penetration. Cell membrane penetration of infectious RRV is initiated by trypsin cleavage of VP3. Neutralizing antibodies can inhibit this direct membrane penetration.

Small-sized and contacting Pt-WC nanostructures on graphene as highly efficient anode catalysts for direct methanol fuel cells.

Science.gov (United States)

Wang, Ruihong; Xie, Ying; Shi, Keying; Wang, Jianqiang; Tian, Chungui; Shen, Peikang; Fu, Honggang

2012-06-11

The synergistic effect between Pt and WC is beneficial for methanol electro-oxidation, and makes Pt-WC catalyst a promising anode candidate for the direct methanol fuel cell. This paper reports on the design and synthesis of small-sized and contacting Pt-WC nanostructures on graphene that bring the synergistic effect into full play. Firstly, DFT calculations show the existence of a strong covalent interaction between WC and graphene, which suggests great potential for anchoring WC on graphene with formation of small-sized, well-dispersed WC particles. The calculations also reveal that, when Pt attaches to the pre-existing WC/graphene hybrid, Pt particles preferentially grow on WC rather than graphene. Our experiments confirmed that highly disperse WC nanoparticles (ca. 5 nm) can indeed be anchored on graphene. Also, Pt particles 2-3 nm in size are well dispersed on WC/graphene hybrid and preferentially grow on WC grains, forming contacting Pt-WC nanostructures. These results are consistent with the theoretical findings. X-ray absorption fine structure spectroscopy further confirms the intimate contact between Pt and WC, and demonstrates that the presence of WC can facilitate the crystallinity of Pt particles. This new Pt-WC/graphene catalyst exhibits a high catalytic efficiency toward methanol oxidation, with a mass activity 1.98 and 4.52 times those of commercial PtRu/C and Pt/C catalysts, respectively. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rotavirus vaccine and diarrhea mortality: quantifying regional variation in effect size

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Black Robert E

2011-04-01

Full Text Available Abstract Background Diarrhea mortality remains a leading cause of child death and rotavirus vaccine an effective tool for preventing severe rotavirus diarrhea. New data suggest vaccine efficacy may vary by region. Methods We reviewed published vaccine efficacy trials to estimate a regional-specific effect of vaccine efficacy on severe rotavirus diarrhea and hospitalizations. We assessed the quality of evidence using a standard protocol and conducted meta-analyses where more than 1 data point was available. Results Rotavirus vaccine prevented severe rotavirus episodes in all regions; 81% of episodes in Latin America, 42.7% of episodes in high-mortality Asia, 50% of episodes in sub-Saharan Africa, 88% of episodes low-mortality Asia and North Africa, and 91% of episodes in developed countries. The effect sizes observed for preventing severe rotavirus diarrhea will be used in LiST as the effect size for rotavirus vaccine on rotavirus-specific diarrhea mortality. Conclusions Vaccine trials have not measured the effect of vaccine on diarrhea mortality. The overall quality of the evidence and consistency observed across studies suggests that estimating mortality based on a severe morbidity reduction is highly plausible.

Human rotavirus genotypes causing acute watery diarrhea among ...

African Journals Online (AJOL)

2014-06-17

Jun 17, 2014 ... vaccine with strains peculiar to this environment should be introduced. ..... Safety and efficacy of an attenuated vaccine against severe rotavirus ... prevalence of adenovirus serotypes 40 and 41, astrovirus, and rotavirus.

Electron microscopic analysis of rotavirus assembly-replication intermediates

International Nuclear Information System (INIS)

Boudreaux, Crystal E.; Kelly, Deborah F.; McDonald, Sarah M.

2015-01-01

Rotaviruses (RVs) replicate their segmented, double-stranded RNA genomes in tandem with early virion assembly. In this study, we sought to gain insight into the ultrastructure of RV assembly-replication intermediates (RIs) using transmission electron microscopy (EM). Specifically, we examined a replicase-competent, subcellular fraction that contains all known RV RIs. Three never-before-seen complexes were visualized in this fraction. Using in vitro reconstitution, we showed that ~15-nm doughnut-shaped proteins in strings were nonstructural protein 2 (NSP2) bound to viral RNA transcripts. Moreover, using immunoaffinity-capture EM, we revealed that ~20-nm pebble-shaped complexes contain the viral RNA polymerase (VP1) and RNA capping enzyme (VP3). Finally, using a gel purification method, we demonstrated that ~30–70-nm electron-dense, particle-shaped complexes represent replicase-competent core RIs, containing VP1, VP3, and NSP2 as well as capsid proteins VP2 and VP6. The results of this study raise new questions about the interactions among viral proteins and RNA during the concerted assembly–replicase process. - Highlights: • Rotaviruses replicate their genomes in tandem with early virion assembly. • Little is known about rotavirus assembly-replication intermediates. • Assembly-replication intermediates were imaged using electron microscopy

Electron microscopic analysis of rotavirus assembly-replication intermediates

Energy Technology Data Exchange (ETDEWEB)

Boudreaux, Crystal E.; Kelly, Deborah F. [Virginia Tech Carilion School of Medicine and Research Institute, Roanoke, VA (United States); McDonald, Sarah M., E-mail: mcdonaldsa@vtc.vt.edu [Virginia Tech Carilion School of Medicine and Research Institute, Roanoke, VA (United States); Department of Biomedical Sciences and Pathobiology, Virginia—Maryland Regional College of Veterinary Medicine, Blacksburg, VA (United States)

2015-03-15

Rotaviruses (RVs) replicate their segmented, double-stranded RNA genomes in tandem with early virion assembly. In this study, we sought to gain insight into the ultrastructure of RV assembly-replication intermediates (RIs) using transmission electron microscopy (EM). Specifically, we examined a replicase-competent, subcellular fraction that contains all known RV RIs. Three never-before-seen complexes were visualized in this fraction. Using in vitro reconstitution, we showed that ~15-nm doughnut-shaped proteins in strings were nonstructural protein 2 (NSP2) bound to viral RNA transcripts. Moreover, using immunoaffinity-capture EM, we revealed that ~20-nm pebble-shaped complexes contain the viral RNA polymerase (VP1) and RNA capping enzyme (VP3). Finally, using a gel purification method, we demonstrated that ~30–70-nm electron-dense, particle-shaped complexes represent replicase-competent core RIs, containing VP1, VP3, and NSP2 as well as capsid proteins VP2 and VP6. The results of this study raise new questions about the interactions among viral proteins and RNA during the concerted assembly–replicase process. - Highlights: • Rotaviruses replicate their genomes in tandem with early virion assembly. • Little is known about rotavirus assembly-replication intermediates. • Assembly-replication intermediates were imaged using electron microscopy.

Protective Effect of Natural Rotavirus Infection in an Indian Birth Cohort

Science.gov (United States)

Gladstone, Beryl P.; Ramani, Sasirekha; Mukhopadhya, Indrani; Muliyil, Jayaprakash; Sarkar, Rajiv; Rehman, Andrea M.; Jaffar, Shabbar; Gomara, Miren Iturriza; Gray, James J.; Brown, David W.G.; Desselberger, Ulrich; Crawford, Sue E.; John, Jacob; Babji, Sudhir; Estes, Mary K.; Kang, Gagandeep

2013-01-01

BACKGROUND More than 500,000 deaths are attributed to rotavirus gastroenteritis annually worldwide, with the highest mortality in India. Two successive, naturally occurring rotavirus infections have been shown to confer complete protection against moderate or severe gastroenteritis during subsequent infections in a birth cohort in Mexico. We studied the protective effect of rotavirus infection on subsequent infection and disease in a birth cohort in India (where the efficacy of oral vaccines in general has been lower than expected). METHODS We recruited children at birth in urban slums in Vellore; they were followed for 3 years after birth, with home visits twice weekly. Stool samples were collected every 2 weeks, as well as on alternate days during diarrheal episodes, and were tested by means of enzyme-linked immunosorbent assay and polymerase-chain-reaction assay. Serum samples were obtained every 6 months and evaluated for seroconversion, defined as an increase in the IgG antibody level by a factor of 4 or in the IgA antibody level by a factor of 3. RESULTS Of 452 recruited children, 373 completed 3 years of follow-up. Rotavirus infection generally occurred early in life, with 56% of children infected by 6 months of age. Levels of reinfection were high, with only approximately 30% of all infections identified being primary. Protection against moderate or severe disease increased with the order of infection but was only 79% after three infections. With G1P[8], the most common viral strain, there was no evidence of homotypic protection. CONCLUSIONS Early infection and frequent reinfection in a locale with high viral diversity resulted in lower protection than has been reported elsewhere, providing a possible explanation why rotavirus vaccines have had lower-than-expected efficacy in Asia and Africa. (Funded by the Wellcome Trust.) PMID:21793745

Global Impact of Rotavirus Vaccination on Childhood Hospitalizations and Mortality From Diarrhea.

Science.gov (United States)

Burnett, Eleanor; Jonesteller, Christine L; Tate, Jacqueline E; Yen, Catherine; Parashar, Umesh D

2017-06-01

In 2006, 2 rotavirus vaccines were licensed. We summarize the impact of rotavirus vaccination on hospitalizations and deaths from rotavirus and all-cause acute gastroenteritis (AGE) during the first 10 years since vaccine licensure, including recent evidence from countries with high child mortality. We used standardized guidelines (PRISMA) to identify observational evaluations of rotavirus vaccine impact among children rotavirus AGE were reduced by a median of 67% overall and 71%, 59%, and 60% in countries with low, medium, and high child mortality, respectively. Implementation of rotavirus vaccines has substantially decreased hospitalizations from rotavirus and all-cause AGE. Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Cost-effectiveness analysis of rotavirus vaccination in Argentina.

Science.gov (United States)

Urueña, Analía; Pippo, Tomás; Betelu, María Sol; Virgilio, Federico; Hernández, Laura; Giglio, Norberto; Gentile, Ángela; Diosque, Máximo; Vizzotti, Carla

2015-05-07

Rotavirus is a leading cause of severe diarrhea in children under 5. In Argentina, the most affected regions are the Northeast and Northwest, where hospitalizations and deaths are more frequent. This study estimated the cost-effectiveness of adding either of the two licensed rotavirus vaccines to the routine immunization schedule. The integrated TRIVAC vaccine cost-effectiveness model from the Pan American Health Organization's ProVac Initiative (Version 2.0) was used to assess health benefits, costs savings, life-years gained (LYGs), DALYs averted, and cost/DALY averted of vaccinating 10 successive cohorts, from the health care system and societal perspectives. Two doses of monovalent (RV1) rotavirus vaccine and three doses of pentavalent (RV5) rotavirus vaccine were each compared to a scenario assuming no vaccination. The price/dose was US$ 7.50 and US$ 5.15 for RV1 and RV5, respectively. We ran both a national and sub-national analysis, discounting all costs and benefits 3% annually. Our base case results were compared to a range of alternative univariate and multivariate scenarios. The number of LYGs was 5962 and 6440 for RV1 and RV5, respectively. The cost/DALY averted when compared to no vaccination from the health care system and societal perspective was: US$ 3870 and US$ 1802 for RV1, and US$ 2414 and US$ 358 for RV5, respectively. Equivalent figures for the Northeast were US$ 1470 and US$ 636 for RV1, and US$ 913 and US$ 80 for RV5. Therefore, rotavirus vaccination was more cost-effective in the Northeast compared to the whole country; and, in the Northwest, health service's costs saved outweighed the cost of introducing the vaccine. Vaccination with either vaccine compared to no vaccination was highly cost-effective based on WHO guidelines and Argentina's 2011 per capita GDP of US$ 9090. Key variables influencing results were vaccine efficacy, annual loss of efficacy, relative coverage of deaths, vaccine price, and discount rate. Compared to no

Dose response and efficacy of a live, attenuated human rotavirus vaccine in Mexican infants.

Science.gov (United States)

Ruiz-Palacios, Guillermo M; Guerrero, M Lourdes; Bautista-Márquez, Aurora; Ortega-Gallegos, Hilda; Tuz-Dzib, Fernando; Reyes-González, Leticia; Rosales-Pedraza, Gustavo; Martínez-López, Julia; Castañón-Acosta, Erika; Cervantes, Yolanda; Costa-Clemens, SueAnn; DeVos, Beatrice

2007-08-01

Immunization against rotavirus has been proposed as the most cost-effective intervention to reduce the disease burden associated with this infection worldwide. The objective of this study was to determine the dose response, immunogenicity, and efficacy of 2 doses of an oral, attenuated monovalent G1[P8] human rotavirus vaccine in children from the same setting in Mexico, where the natural protection against rotavirus infection was studied. From June 2001 through May 2003, 405 healthy infants were randomly assigned to 1 of 3 vaccine groups (virus concentrations 10(4.7), 10(5.2), and 10(5.8) infectious units) and to a placebo group and were monitored to the age of 2 years. The vaccine/placebo was administered concurrently with diphtheria-tetanus toxoid-pertussis/hepatitis B/Haemophilus influenzae type b vaccine at 2 and 4 months of age. After the administration of the first vaccine/placebo dose, weekly home visits to collect information regarding infant health were conducted. Stool samples were collected during each gastroenteritis episode and tested for rotavirus antigen and serotype. The vaccine was well tolerated and induced a greater rate of seroconversion than observed in infants who received placebo. For the pooled vaccine groups, efficacy after 2 oral doses was 80% and 95% against any and severe rotavirus gastroenteritis, respectively. Efficacy was 100% against severe rotavirus gastroenteritis and 70% against severe gastroenteritis of any cause with the vaccine at the highest virus concentration (10(5.8) infectious units). The predominant infecting rotavirus serotype in this cohort was wild-type G1 (85%). Adverse events, including fever, irritability, loss of appetite, cough, diarrhea, and vomiting, were similar among vaccinees and placebo recipients. This new oral, live, attenuated human rotavirus vaccine was safe, immunogenic, and highly efficacious in preventing any and, more importantly, severe rotavirus gastroenteritis in healthy infants. This vaccine

Cost effectiveness of a pentavalent rotavirus vaccine in Oman.

Science.gov (United States)

Al Awaidy, Salah Thabit; Gebremeskel, Berhanu G; Al Obeidani, Idris; Al Baqlani, Said; Haddadin, Wisam; O'Brien, Megan A

2014-06-17

Rotavirus gastroenteritis (RGE) is the leading cause of diarrhea in young children in Oman, incurring substantial healthcare and economic burden. We propose to formally assess the potential cost effectiveness of implementing universal vaccination with a pentavalent rotavirus vaccine (RV5) on reducing the health care burden and costs associated with rotavirus gastroenteritis (RGE) in Oman A Markov model was used to compare two birth cohorts, including children who were administered the RV5 vaccination versus those who were not, in a hypothetical group of 65,500 children followed for their first 5 years of life in Oman. The efficacy of the vaccine in reducing RGE-related hospitalizations, emergency department (ED) and office visits, and days of parental work loss for children receiving the vaccine was based on the results of the Rotavirus Efficacy and Safety Trial (REST). The outcome of interest was cost per quality-adjusted life year (QALY) gained from health care system and societal perspectives. A universal RV5 vaccination program is projected to reduce, hospitalizations, ED visits, outpatient visits and parental work days lost due to rotavirus infections by 89%, 80%, 67% and 74%, respectively. In the absence of RV5 vaccination, RGE-related societal costs are projected to be 2,023,038 Omani Rial (OMR) (5,259,899 United States dollars [USD]), including 1,338,977 OMR (3,481,340 USD) in direct medical costs. However, with the introduction of RV5, direct medical costs are projected to be 216,646 OMR (563,280 USD). Costs per QALY saved would be 1,140 OMR (2,964 USD) from the health care payer perspective. An RV5 vaccination program would be considered cost saving, from the societal perspective. Universal RV5 vaccination in Oman is likely to significantly reduce the health care burden and costs associated with rotavirus gastroenteritis and may be cost-effective from the payer perspective and cost saving from the societal perspective.

Wear resistance and fracture mechanics of WC-Co composites

International Nuclear Information System (INIS)

Kaytbay, Saleh; El-Hadek, Medhat

2014-01-01

Manufacturing of WC-Co composites using the electroless precipitation method at different sintering temperatures of 1 100, 1 250, 1 350 and 1 500 C was successfully achieved. The chemical composition of the investigated materials was 90 wt.% WC with 10 wt.% Co, and 80 wt.% WC with 20 wt.% Co. The specific density, densification, and Vickers microhardness measurements were found to increase with increased sintering temperature for both the WC-Co compositions. The composites of tungsten carbide with 10 wt.% Co had a higher specific density and Vickers microhardness measurements than those for the composites of tungsten carbide with 20 wt.% Co. Composites with WC-10 wt.% Co had better wear resistance. The stress-strain and transverse rupture strength increased monotonically with the increase in sintering temperatures, agreeing with the material hardness and wear resistance behavior. Fractographical scanning electron microscopy analysis of the fracture surface demonstrated a rough characteristic conical shape failure in the direction of the maximum shear stress. A proposed mechanism for the formation of the conical fracture surface under compression testing is presented. (orig.)

Comparative study of the friction and wear behavior of plasma sprayed conventional and nanostructured WC-12%Co coatings on stainless steel

International Nuclear Information System (INIS)

Zhao Xiaoqin; Zhou Huidi; Chen Jianmin

2006-01-01

Conventional and nanostructured WC-12%Co coatings were deposited on 1Cr18Ni9Ti stainless steel substrate using air plasma spraying. The hardness of the coatings was measured, while their friction and wear behavior sliding against Si 3 N 4 at room temperature and elevated temperatures up to 400 deg. C was comparatively studied. The microstructures and worn surface morphologies of the coatings were comparatively analyzed as well by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDXA). It was found that the as-sprayed WC-12%Co coatings were composed of WC as the major phase and W 2 C, WC 1-x , and W 3 Co 3 C as the minor phases. The plasma sprayed nanostructured WC-12%Co coating had much higher hardness and refined microstructures than the conventional WC-12%Co coating. This largely accounted for the better wear resistance of the nanostructured WC-12%Co coating than the conventional coating. Besides, the two types of WC-12%Co coatings showed minor differences in friction coefficients, though the nanostructured WC-12%Co coating roughly had slightly smaller friction coefficient than the conventional coating under the same sliding condition. Moreover, both the conventional and nanostructured WC-12%Co coatings recorded gradually increased wear rate with increasing temperature, and the nanostructured coating was less sensitive to the temperature rise in terms of the wear resistance. The worn surfaces of the conventional WC-12%Co coating at different sliding conditions showed more severe adhesion, microfracture, and peeling as compared to the nanostructured WC-12%Co coating, which well conformed to the corresponding wear resistance of the two types of coatings. The nanostructured WC-12%Co coating with a wear rate as small as 1.01 x 10 -7 mm 3 /Nm at 400 deg. C could be promising candidate coating for the surface-modification of some sliding components subject to harsh working conditions involving elevated

Uptake of yeast (Saccharomyces boulardii) in normal and rotavirus treated intestine.

Science.gov (United States)

Cartwright-Shamoon, J; Dickson, G R; Dodge, J; Carr, K E

1996-01-01

BACKGROUND: There has recently been a growing interest in the use of the non-pathogenic yeast Saccharomyces boulardii, in the treatment of gastrointestinal disorders, including diarrhoea. The full effects of administration of the yeast are not fully understood. AIMS: To investigate the morphological effects of inoculated S boulardii on mouse intestinal villi, both in control animals and those treated with rotavirus. METHODS: Seven day old BALB/c seronegative mice were intubated with either rotavirus (30 microliters orally) or S boulardii (1.5 g/kg) or both rotavirus and S boulardii administered together. Control animals were given saline only. Animals were killed by decapitation 48 hours post-treatment. The middle region of the small intestine was studied using light microscopy and transmission and scanning electron microscopy, including backscattered electron imaging. RESULTS: Animals treated with rotavirus with or without S boulardii developed severe diarrhoea and showed morphological villous changes such as stromal separation and increased epithelial vacuolation. Specimens treated with S boulardii contained yeast particles within the mucosal tissues. CONCLUSION: The administration of S boulardii did not influence the changes produced by rotavirus, but yeast particles appeared to be taken up by the villous mucosa, with the predominant route apparently being uptake between adjacent epithelial cells. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8991857

Rotavirus genotypes associated with acute diarrhea in Egyptian infants.

Science.gov (United States)

Ahmed, Salwa F; Mansour, Adel M; Klena, John D; Husain, Tupur S; Hassan, Khaled A; Mohamed, Farag; Steele, Duncan

2014-01-01

Before the introduction of rotavirus vaccine in Egypt, information on the burden of disease and the circulating rotavirus genotypes is critical to monitor vaccine effectiveness. A cohort of 348 Egyptian children was followed from birth to 2 years of age with twice-weekly home visits to detect diarrheal illness. VP7 and VP4 genes were genotyped by reverse-transcription polymerase chain reaction and DNA sequencing. Forty percentage of children had rotavirus-associated diarrhea at least once by their second birthday. One hundred and twelve children experienced a single rotavirus diarrheal episodes (RDE) at a median age of 9 months; while 27 infants had their second RDE at a median age of 15 months and 1 infant had 3 RDE at the age of 2, 16 and 22 months. Of the 169 RDE, 82% could be assigned a G-type, while 58% had been identified a P-type. The most prevalent genotype was G2 (32%), followed by G1 (24%) and G9 (19%). G2P[4] rotavirus episodes were significantly associated with fever (P = 0.03) and vomiting (P = 0.06) when compared with other genotypes. G2 strains were the predominant genotype causing 50% of the second RDE while G9 represented 25% of the second RDE. Genotypes identified are similar to those detected globally except for absence of G4. Our finding that 75% of the second RDE were due to G2 and G9 indicates a possible reduction in natural protection afforded by these types compared with G1, where 90% of G1 cases did not experience a second xposure, indicating greater protection against recurrent symptomatic infection.

The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

Directory of Open Access Journals (Sweden)

Renström Lena HM

2009-10-01

Full Text Available Abstract The European swine influenza viruses (SIVs show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA of the human-like H1N2 SIV viruses and the neuraminidase (NA of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain. The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant.

Science.gov (United States)

Bálint, Adám; Metreveli, Giorgi; Widén, Frederik; Zohari, Siamak; Berg, Mikael; Isaksson, Mats; Renström, Lena Hm; Wallgren, Per; Belák, Sándor; Segall, Thomas; Kiss, István

2009-10-28

The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

WC-3015 alloy (high-temperature alloy)

International Nuclear Information System (INIS)

Anon.

1974-01-01

WC-3015 Nb alloy containing 28 to 30 Hf, 1 to 2 Zr, 13 to 16 W, 0 to 4 Ta, 0 to 5 Ti, 0.07 to 0.33 C, less than or equal to 0.02 N, less than or equal to 0.03 O, less than or equal to 0.001 H was developed for use at high temperature in oxidizing environments. Its composition can be tailored to meet specific requirements. When WC-3015 is exposed to O at elevated temperature, Hf and Nb oxidized preferentially and HfO 2 dissolves in Nb 2 O 5 to form 6HfO-Nb 2 O 5 . This complex oxide has a tight cubic lattice which resists the diffusion of O into the substrate. During 24-h exposure to air at 2400 0 F, the alloy oxidizes to a depth of approximately 0.035 in. with a surface recession of 0 to 0.004 in. Oxidation resistance of WC-3015 welds and base material can be further enhanced greatly by applying silicide coatings. WC-3015 alloy can be machined by conventional and electrical-discharge methods. It can be hot worked readily by extrusion, forging or rolling. Cold working can be used at room or elevated temperature. It can be welded by the electron-beam or Tig processes. Physical constants, typical mechanical properties at 75 to 2400 0 F, and effects of composition and heat treatment on tensile and stress-rupture properties of the alloy are tabulated

Epidemiology of rotavirus diarrhea in children under 5 years in ...

African Journals Online (AJOL)

Background: Rotavirus still remains the major cause of diarrhea in children below 5 years. No data on rotavirus epidemiology is available in the Northern regions of Cameroon. We aimed to determine the prevalence of group A rotavirus (RVA) in children below 5 years with diarrhea in two regions of Northern Cameroon ...

Study on the relationship between infant rotavirus enteritis and breast feeding

International Nuclear Information System (INIS)

Chen Yanping; Liu Hui; Sun Xuerong; Wei Tao; Wang Bin

2005-01-01

Objective: To study the relationship between infant rotavirus enteritis and breast feeding, with emphasis on early immuno-protection provided by breast feeding as well as later possible hazards with rotavirus carrier mothers. Methods: Stool specimens from 520 infants with diarrhea were screened for rotavirus with colloid gold method. Positive specimens were confirmed with RT-PCR. Results: In local (Qingdao) infants with enteritis, the over-all incidence of rotavirus infection was 31.2%. Positive rate in breast-feeding infants was only 26.8%, being significantly lower than that in bottle-feeding ones (45.2%). The virus infectivity rate in both groups of breast- feeding infants (below 6 months and 7-12 months) was lower than the corresponding rate in the bottle feeding group. However, infant fed from rotavirus carriers had significantly higher fecal positive rate of rotavirus than that in infants fed from non-carriers. Conclusion: (1) At beginning, especially below 6 months, breast-feeding provided important protection again rotavirus enteritis in the infants. (2) certain infections could be transmitted through breast feedings, which deserved closer observation. (authors)

Risk analysis of inter-species reassortment through a Rift Valley fever phlebovirus MP-12 vaccine strain.

Directory of Open Access Journals (Sweden)

Hoai J Ly

Full Text Available Rift Valley fever (RVF is a mosquito-borne zoonotic disease endemic to Africa and the Arabian Peninsula. The causative agent, Rift Valley fever phlebovirus (RVFV, belongs to the genus Phlebovirus in the family Phenuiviridae and causes high rates of abortions in ruminants, and hemorrhagic fever, encephalitis, or blindness in humans. Viral maintenance by mosquito vectors has led to sporadic RVF outbreaks in ruminants and humans in endemic countries, and effective vaccination of animals and humans may minimize the impact of this disease. A live-attenuated MP-12 vaccine strain is one of the best characterized RVFV strains, and was conditionally approved as a veterinary vaccine in the U.S. Live-attenuated RVF vaccines including MP-12 strain may form reassortant strains with other bunyavirus species. This study thus aimed to characterize the occurrence of genetic reassortment between the MP-12 strain and bunyavirus species closely related to RVFV. The Arumowot virus (AMTV and Gouleako goukovirus (GOLV, are transmitted by mosquitoes in Africa. The results of this study showed that GOLV does not form detectable reassortant strains with the MP-12 strain in co-infected C6/36 cells. The AMTV also did not form any reassortant strains with MP-12 strain in co-infected C6/36 cells, due to the incompatibility among N, L, and Gn/Gc proteins. A lack of reassortant formation could be due to a functional incompatibility of N and L proteins derived from heterologous species, and due to a lack of packaging via heterologous Gn/Gc proteins. The MP-12 strain did, however, randomly exchange L-, M-, and S-segments with a genetic variant strain, rMP12-GM50, in culture cells. The MP-12 strain is thus unlikely to form any reassortant strains with AMTV or GOLV in nature.

Lethal infection by a novel reassortant H5N1 avian influenza A virus in a zoo-housed tiger.

Science.gov (United States)

He, Shang; Shi, Jianzhong; Qi, Xian; Huang, Guoqing; Chen, Hualan; Lu, Chengping

2015-01-01

In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, was isolated from the lung sample. Pathogenicity experiments showed that the isolate was able to replicate and cause death in mice. Phylogenetic analysis indicated that HA and NA of A/Tiger/JS/1/2013 clustered with A/duck/Vietnam/OIE-2202/2012 (H5N1), which belongs to clade 2.3.2.1. Interestingly, the gene segment PB2 shared 98% homology with A/wild duck/Korea/CSM-28/20/2010 (H4N6), which suggested that A/Tiger/JS/1/2013 is a novel reassortant H5N1 subtype virus. Immunohistochemical analysis also confirmed that the tiger was infected by this new reassortant HPAI H5N1 virus. Overall, our results showed that this Bengal tiger was infected by a novel reassortant H5N1, suggesting that the H5N1 virus can successfully cross species barriers from avian to mammal through reassortment. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Inactivation of human and simian rotaviruses by ozone

Energy Technology Data Exchange (ETDEWEB)

Vaughn, J.M.; Chen, Y.S.; Lindburg, K.; Morales, D.

1987-09-01

The inactivation of simian rotavirus Sa-11 and human rotavirus type 2 (Wa) by ozone was compared at 4/sup 0/C by using single-particle virus stocks. Although the human strain was clearly more sensitive, both virus types were rapidly inactivated by ozone concentrations of 0.25 mg/liter or greater at all pH levels tested. Comparison of the virucidal activity of ozone with that of chlorine in identical experiments indicated little significant difference in rotavirus-inactivating efficiencies when the disinfectants were used at concentrations of 0.25 mg/liter or greater.

Inactivated rotavirus vaccine induces protective immunity in gnotobiotic piglets.

Science.gov (United States)

Wang, Yuhuan; Azevedo, Marli; Saif, Linda J; Gentsch, Jon R; Glass, Roger I; Jiang, Baoming

2010-07-26

Live oral rotavirus vaccines that are effective in middle and high income countries have been much less immunogenic and effective among infants in resource-limited settings. Several hypotheses might explain this difference, including neutralization of the vaccine by high levels of maternal antibody in serum and breast milk, severe malnutrition, and interference by other flora and viruses in the gut. We have pursued development of an alternative parenteral rotavirus vaccine with the goal of inducing comparable levels of immunogenicity and efficacy in populations throughout the world regardless of their income levels. In the present study, we assessed the immunogenicity and protection of a candidate inactivated rotavirus vaccine (IRV), the human strain CDC-9 (G1P[8]) formulated with aluminum phosphate, against rotavirus infection in gnotobiotic piglets. Three doses of IRV induced high titers of rotavirus-specific IgG and neutralizing activity in the sera of gnotobiotic piglets and protection against shedding of rotavirus antigen following oral challenge with a homologous virulent human strain Wa (G1P[8]). Our findings demonstrate the proof of concept for an IRV in a large animal model and provide evidence and justification for further clinical development as an alternative candidate vaccine. Published by Elsevier Ltd.

Rotavirus epidemiology and vaccine demand: considering Bangladesh chapter through the book of global disease burden.

Science.gov (United States)

Mahmud-Al-Rafat, Abdullah; Muktadir, Abdul; Muktadir, Hasneen; Karim, Mahbubul; Maheshwari, Arpan; Ahasan, Mohammad Mainul

2018-02-01

Rotavirus is the major cause of gastroenteritis in children throughout the world. Every year, a large number of children aged rotavirus-related diarrhoeal diseases. Though these infections are vaccine-preventable, the vast majority of children in low-income countries suffer from the infection. The situation leads to severe economic loss and constitutes a major public health problem. We searched electronic databases including PubMed and Google scholar using the following words: "features of rotavirus," "epidemiology of rotavirus," "rotavirus serotypes," "rotavirus in Bangladesh," "disease burden of rotavirus," "rotavirus vaccine," "low efficacy of rotavirus vaccine," "inactivated rotavirus vaccine". Publications until July 2017 have been considered for this work. Currently, two live attenuated vaccines are available throughout the world. Many countries have included rotavirus vaccines in national immunization program to reduce the disease burden. However, due to low efficacy of the available vaccines, satisfactory outcome has not yet been achieved in developing countries such as Bangladesh. Poor economic, public health, treatment, and sanitation status of the low-income countries necessitate the need for the most effective rotavirus vaccines. Therefore, the present scenario demands the development of a highly effective rotavirus vaccine. In this regard, inactivated rotavirus vaccine concept holds much promise for reducing the current disease burden. Recent advancements in developing an inactivated rotavirus vaccine indicate a significant progress towards disease prophylaxis and control.

Characteristics of Rotavirus Diarrhea in Hospitalized Children in Kosovo

OpenAIRE

Ismaili-Jaha, Vlora; Shala, Muje; Azemi, Mehmedali; Hoxha-Kamberi, Teuta; Avdiu, Muharrem; Spahiu, Shqipe; Jaha, Luan

2014-01-01

Background: Diarrhea is a leading cause of child mortality worldwide. Rotavirus is one of the most common causes of severe diarrhea and dehydration in children. Authors reviewed epidemiological and clinical data of the rotavirus diarrhea in Kosovo. Methods: This is a prospective study carried between January 1st and December 31st 2011. All data, comprising demographics, nutrition, clinical presentation, laboratory findings, management and outcome of the rotavirus diarrhea are collected on the...

Rotavirus vaccination and herd immunity: an evidence-based review

Directory of Open Access Journals (Sweden)

Seybolt LM

2012-06-01

Full Text Available Lorna M Seybolt, Rodolfo E BéguéDepartment of Pediatrics, Division of Infectious Diseases, Louisiana State University Health Sciences Center, New Orleans, LA, USAAbstract: Until recently, rotavirus was the most common cause of diarrhea in infants and young children with over 100 million cases and 400,000 deaths every year worldwide. Yet, its epidemiology is changing rapidly with the introduction of two rotavirus vaccines in the mid 2000s. Both vaccines were shown to be highly efficacious in prelicensure studies to reduce severe rotavirus disease; the efficacy being more pronounced in high- and middle-income countries than in low-income countries. Herd immunity – the indirect protection of unimmunized individuals as a result of others being immunized – was not expected to be a benefit of rotavirus vaccination programs since the vaccines were thought to reduce severe disease but not to decrease virus transmission significantly. Postlicensure studies, however, have suggested that this assumption may need reassessment. Studies in a variety of settings have shown evidence of greater than expected declines in rotavirus disease. While these studies were not designed specifically to detect herd immunity – and few failed to detect this phenomenon – the consistency of the evidence is compelling. These studies are reviewed and described here. While further work is needed, clarifying the presence of herd immunity is not just an academic exercise but an important issue for rotavirus control, especially in lower income countries where the incidence of the disease is highest and the direct protection of the vaccines is lower.Keywords: rotavirus, vaccine, herd immunity, efficacy

Cytokines in the management of rotavirus infection: A systematic review of in vivo studies.

Science.gov (United States)

Gandhi, Gopalsamy Rajiv; Santos, Victor Santana; Denadai, Marina; da Silva Calisto, Valdete Kaliane; de Souza Siqueira Quintans, Jullyana; de Oliveira E Silva, Ana Mara; de Souza Araújo, Adriano Antunes; Narain, Narendra; Cuevas, Luis Eduardo; Júnior, Lucindo José Quintans; Gurgel, Ricardo Queiroz

2017-08-01

Rotavirus is a leading cause of childhood diarrhoea. Rotavirus vaccines are effective against severe rotavirus gastroenteritis, but have lower efficacy in low income countries in Africa. Anti-rotavirus treatment is not available. This study reviews the literature of animal studies evaluating whether cytokine mediated pathways of immune activation could improve rotavirus therapy. We performed a systematic review of articles in English published from 2010 to 2016 reporting agents with in vivo antirotavirus activity for the management of rotavirus infection. The search was carried in PubMed, EMBASE, Scopus and Web of Science. Animal experiments where cytokines were investigated to assess the outcome of rotavirus therapy were included. A total of 869 publications were identified. Of these, 19 pertained the objectives of the review, and 11 articles described the effect of probiotics/commensals on rotavirus infection and immune responses in animals. Eight further in vivo studies evaluated the immunomodulating effects of herbs, secondary metabolites and food-derived products on cytokine responses of rotavirus-infected animals. Studies extensively reported the regulatory roles for T-helper (Th)1 (interferon gamma (IFN-γ), interleukin (IL)-2, IL-12) and Th2 (IL-4, IL-6, IL-10) cytokines responses to rotavirus pathogenesis and immunity, inhibiting rotavirus infection through suppression of inflammation by viral inhibition. Th1 and Th2 cytokines stimulate the immune system, inhibiting rotavirus binding and/or replication in animal models. Th1/Th2 cytokine responses have optimal immunomodulating effects to reduce rotavirus diarrhoea and enhance immune responses in experimental rotavirus infection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of human rotavirus vaccine on severe diarrhea in African infants

OpenAIRE

Madhi, Shabir A; Cunliffe, Nigel A; Steele, Duncan; Witte, Desirée; Kirsten, Mari; Louw, Cheryl; Ngwira, Bagrey; Victor, John C; Gillard, Paul H; Cheuvart, Brigitte B; Han, Htay H; Neuzil, Kathleen M

2016-01-01

: Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. : We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:...

Fracture toughness of a nanoscale WC-Co tool steel

International Nuclear Information System (INIS)

Densley, J.M.; Hirth, J.P.

1997-01-01

Tungsten carbide tool steels, comprising WC particles with 6.7--25wt% Co distributed in the interparticle regions as a quasi-continuous binder phase, can be considered as WC-Co composites. The fracture toughness of such WC-Co composites is dependent on the volume fraction, contiguity and thickness of the cobalt binder, and the size of the tungsten carbide grains. Research has shown that the ductile binder undergoes nearly all the plastic deformation during fracture, which provides the primary energy consuming process that enhances fracture resistance. Recent manufacturing developments have given rise to the production of a WC-6.7wt% Co cermet having an average WC grain size of 70 nm, with a corresponding binder mean thickness, h, of 9 nm calculated from d = h(1-V f )/V f where d = 70 nm and V f = 0.114. This composite has shown a higher wear resistance than that of conventional cermets in proportion to their hardness. Such improvement has been attributed to the difficulty in forming dislocations in the very small grains. There are also indications that the Co binder in the nanoscale cermet contains higher contents of dissolved W and C than for conventional scale cermets. Because plastic deformation is initially confined to the binder phase, it was of interest to perform mode 1 and mixed mode toughness tests on the nanoscale cermet to determine whether flow localization influenced mixed mode toughness as in bulk materials. Two generations of this cermet were provided by Rogers Tool Works. The first generation, A, had lower binder contiguity, with occasional agglomerations of WC grains. The second generation, B, was cleaner, with the cobalt binder more uniformly separating the WC grains

Cost-Effectiveness of Rotavirus Vaccination in France-Accounting for Indirect Protection.

Science.gov (United States)

Yamin, Dan; Atkins, Katherine E; Remy, Vanessa; Galvani, Alison P

Vaccination against rotavirus has shown great potential for reducing the primary cause of severe childhood gastroenteritis. Previous economic evaluations of rotavirus vaccination in France have not modeled the potential impact of vaccines on disease burden via reduced transmission. To determine the cost-effectiveness of the introduction of pentavalent rotavirus vaccination into the French infant vaccination schedule. We developed an age-structured model of rotavirus transmission calibrated to 6 years of French gastroenteritis incidence and vaccine clinical trial data. We evaluated the cost-effectiveness of pentavalent rotavirus vaccination considering that 75% of infants would receive the three-dose vaccine course. Our model predicts that rotavirus vaccination will decrease rotavirus gastroenteritis incidence and associated clinical outcomes in vaccinated and unvaccinated individuals, delay the seasonal peak of infection, and increase the age of infection. From the societal perspective, our base-case scenario predicts that vaccination coverage would be cost-effective at €115 or €135 per vaccine course at €28,500 and €39,500/quality-adjusted life-year (QALY) gained, respectively, and suggests that almost 95% of the financial benefits will be recouped within the first 5 years following vaccination implementation. From the third-party payer perspective, incremental cost-effectiveness ratios ranged from €12,500 to €20,000/QALY, respectively. Our uncertainty analysis suggests that findings were sensitive to various assumptions including the number of hospitalizations, outpatient visits, and the extent of QALY losses per rotavirus episode. Introducing pentavalent rotavirus vaccination into the French infant vaccination schedule would significantly reduce the burden of rotavirus disease in children, and could be cost-effective under plausible conditions. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by

Rotavirus Gastroenteritis is Associated with Increased Morbidity and Mortality in Children with Inherited Metabolic Disorders

LENUS (Irish Health Repository)

Smith, A

2017-04-01

Rotavirus is the leading cause of infantile diarrhoea worldwide in children <5 years1. Although mortality rates are low in Ireland, certain populations are more susceptible to the associated morbidity and mortality of infection. A retrospective chart review of 14 patients with confirmed IMDs who were admitted to Temple Street Children’s Hospital between 2010 to 2015 with rotavirus infection were compared with 14 randomly selected age matched controls. The median length of stay was 7 days (SD25.3) in IMD patients versus 1.5 days (SD 2.1) in the controls. IV fluids were required on average for 4.5 days (range 0-17) in IMD patients versus 0.63 days (range 0-3) in controls. This report highlights the increased morbidity of rotavirus infection in patients with IMD compared to healthy children. This vulnerable population are likely to benefit from the recent introduction of the rotavirus oral vaccination in October 2016.

Suspected zoonotic transmission of rotavirus group A in Danish adults

DEFF Research Database (Denmark)

Midgley, S. E.; Hjulsager, Charlotte Kristiane; Larsen, Lars Erik

2012-01-01

Group A rotaviruses infect humans and a variety of animals. In July 2006 a rare rotavirus strain with G8P[14] specificity was identified in the stool samples of two adult patients with diarrheoa, who lived in the same geographical area in Denmark. Nucleotide sequences of the VP7, VP4, VP6, and NSP4...... genes of the identified strains were identical. Phylogenetic analyses showed that both Danish G8P[14] strains clustered with rotaviruses of animal, mainly, bovine and caprine, origin. The high genetic relatedness to animal rotaviruses and the atypical epidemiological features suggest that these human G8...

Biennial pattern of rotavirus gastroenteritis in the Netherlands and a shifting age distribution following a low rotavirus season, 2010-2016.

NARCIS (Netherlands)

Verberk, J.D.M.; Pijnacker, R.; Bruijning-Verhagen, P.; Franz, E.; Vennema, H.; Hooiveld, M.; Hahné, S.J.M.; Melker, H.E. de

2017-01-01

A hyper-endemic rotavirus season was expected after a low-endemic 2014 season in the Netherlands. Rotavirus detections were however similar in 2015 and lower in 2016 compared with 2010-2013. Gastroenteritis consultations rates were also similar in 2015, but the age-distribution shifted to older

Efficacy of a Low-Cost, Heat-Stable Oral Rotavirus Vaccine in Niger.

Science.gov (United States)

Isanaka, Sheila; Guindo, Ousmane; Langendorf, Celine; Matar Seck, Amadou; Plikaytis, Brian D; Sayinzoga-Makombe, Nathan; McNeal, Monica M; Meyer, Nicole; Adehossi, Eric; Djibo, Ali; Jochum, Bruno; Grais, Rebecca F

2017-03-23

Each year, rotavirus gastroenteritis is responsible for about 37% of deaths from diarrhea among children younger than 5 years of age worldwide, with a disproportionate effect in sub-Saharan Africa. We conducted a randomized, placebo-controlled trial in Niger to evaluate the efficacy of a live, oral bovine rotavirus pentavalent vaccine (BRV-PV, Serum Institute of India) to prevent severe rotavirus gastroenteritis. Healthy infants received three doses of the vaccine or placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and were graded on the basis of the score on the Vesikari scale (which ranges from 0 to 20, with higher scores indicating more severe disease). The primary end point was the efficacy of three doses of vaccine as compared with placebo against a first episode of laboratory-confirmed severe rotavirus gastroenteritis (Vesikari score, ≥11) beginning 28 days after dose 3. Among the 3508 infants who were included in the per-protocol efficacy analysis, there were 31 cases of severe rotavirus gastroenteritis in the vaccine group and 87 cases in the placebo group (2.14 and 6.44 cases per 100 person-years, respectively), for a vaccine efficacy of 66.7% (95% confidence interval [CI], 49.9 to 77.9). Similar efficacy was seen in the intention-to-treat analyses, which showed a vaccine efficacy of 69.1% (95% CI, 55.0 to 78.7). There was no significant between-group difference in the risk of adverse events, which were reported in 68.7% of the infants in the vaccine group and in 67.2% of those in the placebo group, or in the risk of serious adverse events (in 8.3% in the vaccine group and in 9.1% in the placebo group); there were 27 deaths in the vaccine group and 22 in the placebo group. None of the infants had confirmed intussusception. Three doses of BRV-PV, an oral rotavirus vaccine, had an efficacy of 66.7% against severe rotavirus gastroenteritis among infants in Niger. (Funded by M�

Infrared processed Cu composites reinforced with WC particles

International Nuclear Information System (INIS)

Deshpande, P.K.; Li, J.H.; Lin, R.Y.

2006-01-01

Copper matrix composites with WC particle reinforcements have been prepared with an innovative infrared infiltration technique. The volume content of the reinforcement particles in the composite is about 53%. The relative composite density of as high as 99.9% has been obtained with this process. The electric conductivity of composites prepared in this study as determined by a four-point probe method, is similar to commercially available Cu/W composites containing 52 vol% tungsten. Microhardness, microstructure and wear resistance of the composites were also determined. The microstructure of Cu/WC composite reveals excellent wetting between the two constituent phases, WC and copper. The microhardness values of all completely infiltrated Cu/WC composites were in the range of 360-370 HV which is significantly higher than the microhardness of pure copper, 65 HV. Wear resistance of the composites was determined with a pin on disk wear test technique. The wear test results show that composites prepared in this study performed much better than those commercially available Cu/W composites by more than two-fold against silicon carbide abrasive disks

Determinants of rotavirus transmission : a lag non-linear time series analysis

NARCIS (Netherlands)

van Gaalen, Rolina D; van de Kassteele, Jan; Hahné, Susan J M; Bruijning-Verhagen, Patricia; Wallinga, Jacco

Rotavirus is a common viral infection among young children. As in many countries, the infection dynamics of rotavirus in the Netherlands are characterized by an annual winter peak, which was notably low in 2014. Previous work suggested an association between weather factors and both rotavirus

Rotavirus in Ireland: national estimates of disease burden, 1997 to 1998.

LENUS (Irish Health Repository)

Lynch, M

2012-02-03

BACKGROUND: We estimated the disease burden caused by rotavirus hospitalizations in the Republic of Ireland by using national data on the number of hospitalizations for diarrhea in children and laboratory surveillance of confirmed rotavirus detections. METHODS: We examined trends in diarrheal hospitalizations among children <5 years old as coded by ICD-9-CM for the period January, 1997, to December, 1998. We collated data on laboratory-confirmed rotavirus detections nationally for the same period among children <2 years old. We calculated the overall contribution of rotavirus to laboratory-confirmed intestinal disease in children <5 years old from INFOSCAN, a disease bulletin for one-third of the population. We compared data from all sources and estimated the proportion of diarrheal hospitalizations that are likely the result of rotavirus in children <5 years old. RESULTS: In children <5 years old, 9% of all hospitalizations are for diarrheal illness. In this age group 1 in 8 are hospitalized for a diarrheal illness, and 1 in 17 are hospitalized for rotavirus by 5 years of age. In hospitalized children <2 years old, 1 in 38 have a laboratory confirmed rotavirus infection. CONCLUSIONS: The disease burden of rotavirus hospitalizations is higher than in other industrialized countries. Access to comprehensive national databases may have contributed to the high hospitalization rates, as well as a greater tendency to hospitalize children with diarrhea in Ireland.

Species A rotavirus NSP3 acquires its translation inhibitory function prior to stable dimer formation.

Directory of Open Access Journals (Sweden)

Hugo I Contreras-Treviño

Full Text Available Species A rotavirus non-structural protein 3 (NSP3 is a translational regulator that inhibits or, under some conditions, enhances host cell translation. NSP3 binds to the translation initiation factor eIF4G1 and evicts poly-(A binding protein (PABP from eIF4G1, thus inhibiting translation of polyadenylated mRNAs, presumably by disrupting the effect of PABP bound to their 3'-ends. NSP3 has a long coiled-coil region involved in dimerization that includes a chaperone Hsp90-binding domain (HS90BD. We aimed to study the role in NSP3 dimerization of a segment of the coiled-coil region adjoining the HS90BD. We used a vaccinia virus system to express NSP3 with point mutations in conserved amino acids in the coiled-coil region and determined the effects of these mutations on translation by metabolic labeling of proteins as well as on accumulation of stable NSP3 dimers by non-dissociating Western blot, a method that separates stable NSP3 dimers from the monomer/dimerization intermediate forms of the protein. Four of five mutations reduced the total yield of NSP3 and the formation of stable dimers (W170A, K171E, R173E and R187E:K191E, whereas one mutation had the opposite effects (Y192A. Treatment with the proteasome inhibitor MG132 revealed that stable NSP3 dimers and monomers/dimerization intermediates are susceptible to proteasome degradation. Surprisingly, mutants severely impaired in the formation of stable dimers were still able to inhibit host cell translation, suggesting that NSP3 dimerization intermediates are functional. Our results demonstrate that rotavirus NSP3 acquires its function prior to stable dimer formation and remain as a proteasome target throughout dimerization.

Hot isostatic pressing of nanosized WC-Co hardmetals

International Nuclear Information System (INIS)

Azcona, I.; Ordonez, A.; Sanchez, J.M.; Castro, F.; Dominguez, L.

2001-01-01

A new technique based on hot isostatic pressing (HIP) has been developed to produce dense nanosized WC-Co hardmetals without the addition of grain growth inhibitors. The glass encapsulation process is the key for the effective application of isostatic pressure at temperatures well below those usually required for reaching the closed porosity state in the WC-Co system. Fully dense WC-Co samples with cobalt contents ranging from 10 to 12 wt. % have been obtained by this technique at temperatures between 1000 o C and 1200 o C with 150 MPa of applied isostatic pressure for 30 minutes. The role of isostatic pressure on the activation of densification mechanisms is discussed. (author)

Impact of self-financed rotavirus vaccines on hospital stays and costs in Spain after a 3-year introductory period.

Science.gov (United States)

Redondo-González, O; Tenías-Burillo, J M; Ruiz-Gonzalo, J

2017-07-01

Vaccination has reduced rotavirus hospitalizations by 25% in European regions with low-moderate vaccine availability. We aimed to quantify the reduction in hospital costs after the longest period in which Rotarix® and Rotateq® were simultaneously commercially available in Spain. Cases, length of stay (LOS), and diagnosis-related groups (DRGs) were retrieved from the Minimum Basic Data Set. Healthcare expenditure was estimated through the cost accounting system Gescot®. DRGs were clustered: I, non-bacterial gastroenteritis with complications; II, without complications; III, requiring surgical/other procedures or neonatal cases (highest DRG weights). Comparisons between pre (2003-2005)- and post-vaccine (2007-2009) hospital stays and costs by DRG group were made. Rotaviruses were the most common agents of specific-coded gastroenteritis (N = 1657/5012). LOS and extended LOS of rotaviruses fell significantly in 2007-2009 (β-coefficient = -0·43, 95% confidence intervals (95% CI) -0·68 to -0·17; and odds ratio 0·62, 95% CI 0·50-0·76, respectively). Overall, costs attributable to rotavirus hospitalizations fell approximately €244 per patient (95% CI -365 to -123); the decrease in DRG group III was €2269 per patient (95% CI -4098 to -380). We concluded modest savings in hospital costs, largely attributable to cases with higher DRG weights, and a faster recovery. A universal rotavirus vaccination program deserves being re-evaluated, regarding its potential high impact on both at-risk children and societal costs.

Rotavirus epidemiology and surveillance before vaccine introduction in Argentina, 2012-2014.

Science.gov (United States)

Degiuseppe, Juan Ignacio; Reale, Ezequiel Agustín; Stupka, Juan Andrés

2017-03-01

Group A Rotavirus has been widely described as one of the most important infantile diarrheal pathogens worldwide. In Argentina, it is responsible for over 200,000 acute diarrhea cases and from 30 to 50 deaths annually in children under 5 years. The aim of this study is to analyze frequency, seasonality, age group distribution, and circulating genotypes based on data notified in the 2012-2014 period and in turn to assess the pre-vaccine scenario, considering that rotavirus vaccine was introduced in 2015. Data were taken from the Viral Diarrhea Notification module of the Argentine SNVS-SIVILA surveillance tool. Analyses of circulating genotypes were performed on rotavirus-positive stool specimens by conventional binary characterization of the outermost capsid genes. Overall data showed rotavirus detection in about 25% of samples tested, and higher rates in children under 2 years old were observed. Rotavirus positive cases were distributed according to a typical winter seasonal pattern. A heterogeneous regional pattern of prevalence was also observed, with higher rates detected in the North region. Genotype co-circulation and annual fluctuation were observed. In general, G1P[8], G2P[4], G3P[8], and G12P[8] were the most frequently detected genotypes. This study represents the last survey taken of a population considered to be naïve. J. Med. Virol. 89:423-428, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Detection and distribution of rotavirus in raw sewage and creeks in Sao Paulo, Brazil

Energy Technology Data Exchange (ETDEWEB)

Mehnert, D.U.; Stewien, K.E. (Univ. of Sao Paulo (Brazil))

1993-01-01

Rotavirus invection is an important cause of hospitalization and mortality of infants and children in developing countries, especially where the water supply and sewage disposal systems are in precarious conditions. This report describes the detection, quantitation, and distribution of rotaviruses in domestic sewage and sewage polluted creeks in the city of San Paulo. 22 refs., 1 fig., 3 tabs.

Public finance of rotavirus vaccination in India and Ethiopia: an extended cost-effectiveness analysis.

Science.gov (United States)

Verguet, Stéphane; Murphy, Shane; Anderson, Benjamin; Johansson, Kjell Arne; Glass, Roger; Rheingans, Richard

2013-10-01

An estimated 4% of global child deaths (approximately 300,000 deaths) were attributed to rotavirus in 2010. About a third of these deaths occurred in India and Ethiopia. Public finance of rotavirus vaccination in these two countries could substantially decrease child mortality and also reduce rotavirus-related hospitalizations, prevent health-related impoverishment and bring significant cost savings to households. We use a methodology of 'extended cost-effectiveness analysis' (ECEA) to evaluate a hypothetical publicly financed program for rotavirus vaccination in India and Ethiopia. We measure program impact along four dimensions: 1) rotavirus deaths averted; 2) household expenditures averted; 3) financial risk protection afforded; 4) distributional consequences across the wealth strata of the country populations. In India and Ethiopia, the program would lead to a substantial decrease in rotavirus deaths, mainly among the poorer; it would reduce household expenditures across all income groups and it would effectively provide financial risk protection, mostly concentrated among the poorest. Potential indirect benefits of vaccination (herd immunity) would increase program benefits among all income groups, whereas potentially decreased vaccine efficacy among poorer households would reduce the equity benefits of the program. Our approach incorporates financial risk protection and distributional consequences into the systematic economic evaluation of vaccine policy, illustrated here with the case study of public finance for rotavirus vaccination. This enables selection of vaccine packages based on the quantitative inclusion of information on equity and on how much financial risk protection is being bought per dollar expenditure on vaccine policy, in addition to how much health is being bought. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rotavirus I in feces of a cat with diarrhea.

Science.gov (United States)

Phan, Tung G; Leutenegger, Christian M; Chan, Roxanne; Delwart, Eric

2017-06-01

A divergent rotavirus I was detected using viral metagenomics in the feces of a cat with diarrhea. The eleven segments of rotavirus I strain Felis catus encoded non-structural and structural proteins with amino acid identities ranging from 25 to 79% to the only two currently sequenced members of that viral species both derived from canine feces. No other eukaryotic viral sequences nor bacterial and protozoan pathogens were detected in this fecal sample suggesting the involvement of rotavirus I in feline diarrhea.

Rotavirus genotype shifts among Swedish children and adults-Application of a real-time PCR genotyping.

Science.gov (United States)

Andersson, Maria; Lindh, Magnus

2017-11-01

It is well known that human rotavirus group A is the most important cause of severe diarrhoea in infants and young children. Less is known about rotavirus infections in other age groups, and about how rotavirus genotypes change over time in different age groups. Develop a real-time PCR to easily genotype rotavirus strains in order to monitor the pattern of circulating genotypes. In this study, rotavirus strains in clinical samples from children and adults in Western Sweden during 2010-2014 were retrospectively genotyped by using specific amplification of VP 4 and VP 7 genes with a new developed real-rime PCR. A genotype was identified in 97% of 775 rotavirus strains. G1P[8] was the most common genotype representing 34.9%, followed by G2P[4] (28.3%), G9P[8] (11.5%), G3P[8] (8.1%), and G4P[8] (7.9%) The genotype distribution changed over time, from predominance of G1P[8] in 2010-2012 to predominance of G2P[4] in 2013-2014. There were also age-related differences, with G1P[8] being the most common genotype in children under 2 years (47.6%), and G2P[4] the most common in those over 70 years of age (46.1%.). The shift to G2P[4] in 2013-2014 was associated with a change in the age distribution, with a greater number of rotavirus positive cases in elderly than in children. By using a new real-time PCR method for genotyping we found that genotype distribution was age related and changed over time with a decreasing proportion of G1P[8]. Copyright © 2017. Published by Elsevier B.V.

molecular identification of rotavirus strains associated with diarrhea

African Journals Online (AJOL)

DR. AMINU

ABSTRACT. The study was carried out to determine the molecular characteristics of the rotavirus strains associated with diarrhea among children in Kwara state, Nigeria. A total of 150 stool samples were collected from diarrheic children. The stool samples were screened for rotavirus,using Enzyme linked Immunosorbent ...

Molecular identification of rotavirus strains associated with diarrhea ...

African Journals Online (AJOL)

The study was carried out to determine the molecular characteristics of the rotavirus strains associated with diarrhea among children in Kwara state, Nigeria. A total of 150 stool samples were collected from diarrheic children. The stool samples were screened for rotavirus,using Enzyme linked Immunosorbent assay (ELISA).

The clinical appearance of neonatal rotavirus infection: Association ...

African Journals Online (AJOL)

BackgroundRotavirus is the most important aetiological agent causing severe gastroenteritis in children <2 years of age in South Africa and worldwide. Most endemic neonatal nursery strains are thought to be asymptomatic. However, serious conditions have been reported to be associated with rotavirus infection, such as ...

Effects of Lactobacillus rhamnosus GG on the maturation and differentiation of dendritic cells in rotavirus-infected mice.

Science.gov (United States)

Jiang, Y; Ye, L; Cui, Y; Yang, G; Yang, W; Wang, J; Hu, J; Gu, W; Shi, C; Huang, H; Wang, C

2017-08-24

Rotavirus-related diarrhoea is considered one of the most important diseases in field animal production. In addition to the classic vaccine strategy, a number of studies have utilised probiotics, such as Lactobacillus rhamnosus GG (LGG), to prevent rotavirus-induced diarrhoea. Although it has been partially revealed that Toll-like receptors (TLRs) are involved in the LGG-mediated protection against rotavirus infection, the details of the underlying immunologic mechanisms remain largely unknown. In this study, three-to-four-week-old female BALB/c mice were divided into three groups and orally administered phosphate buffered saline (PBS), PBS plus rotavirus or LGG plus rotavirus, respectively. The differentiation and maturation of dendritic cells (DCs) were then determined by FACS, the expression levels of TLR-3 and nuclear factor kappa beta (NF-κB) were evaluated using real time PCR, and the production of inflammatory cytokines in mesenteric lymph nodes (MLNs) were determined by ELISA. The results demonstrated that rotavirus infection significantly increased the percentage of CD11c + CD11b + CD8a - DCs and decreased the percentage of CD11c + CD11b - CD8a + DCs in MLNs. By contrast, the presence of LGG significantly decreased the percentage of CD11c + CD11b + CD8a - DCs and increased the percentage of CD11c + CD11b - CD8a + DCs, which indicates that the differentiation of DCs is involved in the protective effects of LGG. Rotavirus infection also resulted in the increased expression of surface markers such as CD40, CD80 and MHC-II in DCs, and the administration of LGG significantly increased the expression level further. The mRNA levels of TLR-3 and NF-κB in the intestine and MLNs were also significantly increased in the presence of rotavirus, which was further increased in the presence of LGG. The production of inflammatory cytokines was also determined, and the results showed that rotavirus caused the increased production of interleukin (IL)-12 and tumour necrosis

Economic evaluation of routine infant rotavirus immunisation program in Japan.

Science.gov (United States)

Hoshi, Shu-Ling; Kondo, Masahide; Okubo, Ichiro

2017-05-04

Two rotavirus vaccines are currently available in Japan. We estimated the incremental cost-effectiveness ratio (ICER) of routine infant rotavirus immunisation program without defining which vaccine to be evaluated, which reflects the current deliberation at the Health Science Council in charge of Immunisation and Vaccine established by the Ministry of Health, Labor and Welfare of Japan. Three ICERs were estimated, one from payers' perspective and 2 from societal perspective depending on the scenarios to uptake vaccines. The health statuses following the birth cohort were as follows: not infected by rotavirus, asymptomatic infection, outpatients after infection, hospitalised after infection, developing encephalitis/encephalopathy followed by recovery, sequelae, and death. Costs of per course of vaccination was ¥30,000 (US$283; US$1 = ¥106). The model runs for 60 months with one month cycle. From payers' perspective, estimated ICERs were ¥6,877,000 (US$64,877) per QALY. From societal perspective, immunisation program turns out to be cost-saving for 75% simultaneous vaccination scenario, while it is at ¥337,000 (US$3,179) per QALY gained with vaccine alone scenario. The probability of rotavirus immunisation program to be under ¥5,000,000 (US$47,170) per QALY was at 19.8%, 40.7%, and 75.6% when costs per course of vaccination were set at ¥30,000 (US$283), ¥25,000 (US$236), and ¥20,000 (US$189), respectively. Rotavirus immunisation program has a potential to be cost-effective from payers' perspective and even cost-saving from societal perspective in Japan, however, caution should be taken with regard to the interpretation of the results as cost-effectiveness is critically dependent on vaccination costs.

Survival and detection of rotaviruses on environmental surfaces in day care centers.

Science.gov (United States)

Keswick, B H; Pickering, L K; DuPont, H L; Woodward, W E

1983-01-01

Previously, we demonstrated that children in day care centers commonly experience diarrhea due to rotavirus, giardia, and bacterial pathogens. Multiple agents frequently coexist, and the environment is heavily contaminated with enteric bacteria during outbreaks. A study of environmental surface contamination with rotavirus was performed during three non-outbreak periods. Of 25 samples collected from environmental surfaces and teachers hands at a day care center, 4 (16%) were positive for rotavirus antigen when a fluorescence assay was used. We also examined the survival of two animal viruses, rotavirus SA-11 and poliovirus type 1, and bacteriophage 12 on similar environmental surfaces in a laboratory. Poliovirus type 1 and bacteriophage f2 were more resistant to drying than rotavirus SA-11 and could be recovered after a 90-min exposure on a dry surface. Rotavirus SA-11 could be detected for 30 min. All three viruses survived longer when they were suspended in fecal material than when they were suspended in distilled water. These data suggest that several agents, including rotavirus, can remain viable on contaminated surfaces long enough to be transmitted to susceptible children. This finding helps explain why rotavirus shows a mode of spread like that of parasitic and bacterial agents within day care center settings. PMID:6314896

Report of the 5th European expert meeting on rotavirus vaccination (EEROVAC).

Science.gov (United States)

de Hoog, Marieke L A; Vesikari, Timo; Giaquinto, Carlo; Huppertz, Hans-Iko; Martinon-Torres, Federico; Bruijning-Verhagen, Patricia

2018-04-03

The Fifth European Expert Meeting on Rotavirus Vaccination was convened in Utrecht, The Netherlands, in March 2017. The 2-day meeting included invited lectures as well as original oral and poster presentations and brought together experts from 21 countries. Summary findings of the meeting include: Rotavirus vaccination programmes in Europe have resulted in reductions of 60-90% in rotavirus outpatient visits and hospitalizations. Long term trends indicate this impact is sustained over the years. Herd effects, protecting unvaccinated children and neonates too young to be vaccinated have been observed in many European countries. Early evidence now also suggests that rotavirus vaccination may be instrumental in the prevention of celiac disease. Special attention should be given to preterm infants, who may age out of the vaccination window before hospital discharge and to HIV infected children who are at increased risk of severe rotavirus AGE. There is a small but increased risk of IS following rotavirus vaccination and parents should therefore be informed about possible signs and symptoms of IS. New insights in rotavirus genetic susceptibility and interactions with microbiome may open opportunities for interventions to improve protection by vaccination, in particular in LMIC. The development of several novel rotavirus vaccines discussed at the meeting is also promising in this respect.

Human rotavirus genotypes causing acute watery diarrhea among ...

African Journals Online (AJOL)

Background: Diarrhea is a major cause of childhood morbidity and mortality in the developing countries. Rotavirus is a major cause of acute watery diarrhea. Aim: This study aims at characterizing the prevalent rotavirus G-genotypes among under.five children presenting with acute watery diarrhea in Benin City, Nigeria.

epidemiology of rotavirus and astrovirus infections in children

African Journals Online (AJOL)

Emmanuel Ameh

Abstract. Background: Recent estimates attribute 527 000 deaths in children less than five years of age to rotavirus diarrhea annually, with 145 000 occurring in sub-Saharan Africa. Human astroviruses have been identified as one of the most frequent causes of infantile diarrhea, second in incidence only to rotavirus.

The incidence and clinical presentation of infantile rotavirus ...

African Journals Online (AJOL)

Objectives. An effective vaccine is needed to protect against severe rotavirus disease, an important cause of gastroenteritis. Since there are no data on the incidence and antigenic diversity of rotavirus infection in Sierra Leone, we studied its epidemiology to enable an effective vaccine strategy to be designed. Methods.

Human rotavirus group a serotypes causing gastroenteritis in ...

African Journals Online (AJOL)

Background: Rotavirus remains a leading cause of acute gastroenteritis in children worldwide with an estimated 2000 deaths each day in developing countries. Due to HIV/AIDS scourge in Kenya, it is possible that rotavirus-related gastroenteritis has been aggravated in adults. The Global Alliance for Immunizations has ...

Development and kinetic analysis of cobalt gradient formation in WC-Co composites

Science.gov (United States)

Guo, Jun

2011-12-01

Functionally graded cemented tungsten carbide (FG WC-Co) is one of the main research directions in the field of WC-Co over decades. Although it has long been recognized that FG WC-Co could outperform conventional homogeneous WC-Co owing to its potentially superior combinations of mechanical properties, until recently there has been a lack of effective and economical methods to make such materials. The lack of the technology has prevented the manufacturing and industrial applications of FG WC-Co from becoming a reality. This dissertation is a comprehensive study of an innovative atmosphere heat treatment process for producing FG WC-Co with a surface cobalt compositional gradient. The process exploited a triple phase field in W-C-Co phase diagram among three phases (solid WC, solid Co, and liquid Co) and the dependence of the migration of liquid Co on temperature and carbon content. WC-Co with a graded surface cobalt composition can be achieved by controlling the diffusion of carbon transported from atmosphere during sintering or during postsintering heat treatment. The feasibility of the process was validated by the successful preparations of FG WC-Co via both carburization and decarburization process following conventional liquid phase sintering. A study of the carburization process was undertaken to further understand and quantitatively modeled this process. The effects of key processing parameters (including heat treating temperature, atmosphere, and time) and key materials variables (involving Co content, WC grain size, and addition of grain growth inhibitors) on the formation of Co gradients were examined. Moreover, a carbon-diffusion controlled kinetic model was developed for simulating the formation of the gradient during the process. The parameters involved in this model were determined by thermodynamic calculations and regression-fit of simulation results with experimental data. In summary, this research first demonstrated the principle of the approach

Phase size distribution in WC/Co hardmetal

International Nuclear Information System (INIS)

Roebuck, B.; Bennett, E.G.

1986-01-01

A high-resolution field emission scanning electron microscope was used to perform accurate quantitative metallography on a variety of WC/Co hardmetals. Particular attention was paid to obtaining the mean size and size distribution of the cobalt phase by linear analysis. Cobalt regions are frequently submicron and difficult to resolve adequately by conventional methods. The WC linear intercept distributions, and contiguity were also measured at the same time. The results were used to examine the validity of theoretic derivations of cobalt intercept size

Pharmacoeconomic spotlight on rotavirus vaccine RIX4414 (Rotarix™) in developed countries.

Science.gov (United States)

Plosker, Greg L

2012-12-01

The most common cause of severe diarrhea in infants and young children is rotavirus gastroenteritis (RVGE), which is associated with significant morbidity, healthcare resource use, and direct and indirect costs in industrialized nations. The monovalent rotavirus vaccine RIX4414 (Rotarix™) is administered as a two-dose oral series in infants and has demonstrated protective efficacy against RVGE in clinical trials conducted in developed countries. In addition, various naturalistic studies have demonstrated 'real-world' effectiveness after the introduction of widespread rotavirus vaccination programs in the community setting. Numerous cost-effectiveness analyses have been conducted in developed countries in which a universal rotavirus vaccination program using RIX4414 was compared with no universal rotavirus vaccination program. There was a high degree of variability in base-case results across studies even when the studies were conducted in the same country, often reflecting differences in the selection of data sources or assumptions used to populate the models. In addition, results were sensitive to plausible changes in a number of key input parameters. As such, it is not possible to definitively state whether a universal rotavirus vaccination program with RIX4414 is cost effective in developed countries, although results of some analyses in some countries suggest this is the case. In addition, international guidelines advocate universal vaccination of infants and children against rotavirus. It is also difficult to draw conclusions regarding the cost effectiveness of rotavirus vaccine RIX4414 relative to that of the pentavalent rotavirus vaccine, which is administered as a three-dose oral series. Although indirect comparisons in cost-effectiveness analyses indicate that RIX4414 provided more favorable incremental cost-effectiveness ratios when each vaccine was compared with no universal rotavirus vaccination program, results were generally sensitive to vaccine

Epidemiology of rotavirus-associated hospital admissions in the province of Ferrara, Italy.

Science.gov (United States)

Marsella, Maria; Raimondi, Licia; Bergamini, Mauro; Sprocati, Monica; Bigi, Ettore; De Sanctis, Vincenzo; Borgna-Pignatti, Caterina; Gabutti, Giovanni

2009-12-01

Hospital discharge forms with specific codes for rotavirus gastroenteritis in children 0 to 14 years of age were reviewed in the period 2003-2005 in the province of Ferrara. A total of 4,238 children were admitted to the pediatric departments; 151 patients were diagnosed with rotavirus gastroenteritis. The average annual rate of hospitalization for rotavirus gastroenteritis was 1.54/1,000 children Italy and underline the potential impact of rotavirus vaccination in our province.

Reduction in Diarrhea- and Rotavirus-related Healthcare Visits Among Children Introduction in Zimbabwe.

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Mujuru, Hilda A; Yen, Catherine; Nathoo, Kusum J; Gonah, Nhamo A; Ticklay, Ismail; Mukaratirwa, Arnold; Berejena, Chipo; Tapfumanei, Ottias; Chindedza, Kenneth; Rupfutse, Maxwell; Weldegebriel, Goitom; Mwenda, Jason M; Burnett, Eleanor; Tate, Jacqueline E; Parashar, Umesh D; Manangazira, Portia

2017-10-01

In Zimbabwe, rotavirus accounted for 41%-56% of acute diarrhea hospitalizations before rotavirus vaccine introduction in 2014. We evaluated rotavirus vaccination impact on acute diarrhea- and rotavirus-related healthcare visits in children. We examined monthly and annual acute diarrhea and rotavirus test-positive hospitalizations and Accident and Emergency Department visits among children introduction (2012-2013) with postvaccine introduction (2015 and 2016) data for 2 of the hospitals. We examined monthly acute diarrhea hospitalizations by year and age group for 2013-2016 from surveillance hospital registers and monthly acute diarrhea outpatient visits reported to the Ministry of Health and Child Care during 2012-2016. Active surveillance data showed winter seasonal peaks in diarrhea- and rotavirus-related visits among children introduction; the percentage of rotavirus test-positive visits followed a similar seasonal pattern and decrease. Hospital register data showed similar pre-introduction seasonal variation and post-introduction declines in diarrhea hospitalizations among children 0-11 and 12-23 months of age. Monthly variation in outpatient diarrhea-related visits mirrored active surveillance data patterns. At 2 surveillance hospitals, the percentage of rotavirus-positive visits declined by 40% and 43% among children 0-11 months of age and by 21% and 33% among children 12-23 months of age in 2015 and 2016, respectively. Initial reductions in diarrheal illness among children introduction are encouraging. These early results provide evidence to support continued rotavirus vaccination and rotavirus surveillance in Zimbabwe.

Effectiveness of Pentavalent Rotavirus Vaccine Against a Diverse Range of Circulating Strains in Nicaragua.

Science.gov (United States)

Patel, Manish; Pedreira, Cristina; De Oliveira, Lúcia Helena; Tate, Jacqueline; Leshem, Eyal; Mercado, Juan; Umaña, Jazmina; Balmaceda, Angel; Reyes, Martha; Kerin, Tara; McDonald, Sharla; Gentsch, Jon; Bowen, Michael D; Parashar, Umesh

2016-05-01

Because >60 rotavirus strains have been reported worldwide, concerns exist about strain replacement after the introduction of rotavirus vaccines, particularly in developing countries with diverse strains and lower efficacy. We used the case-control design in 4 hospitals in Nicaragua to assess strain-specific vaccine effectiveness (VE) of a pentavalent rotavirus vaccine (RotaTeq) against rotavirus diarrhea. Cases were identified through prospective strain surveillance with reverse transcription-polymerase chain reaction for 3 years among children hospitalized for diarrhea, and controls were children negative for rotavirus. We enrolled 1178 case-patients, 1082 (92%) with G and P typing, and 4927 controls. A different strain predominated each year with increasing age of the vaccine-eligible cohort during the study period: G2P[4] in 2008 (97%; mean age, 11.9 months), G1P[8] in 2009 (55%; mean age, 17.0 months), and G3P[8] in 2010 (78%; mean age, 17.3 months). Overall VE was 45% (95% confidence interval, 25%-59%). Regardless of the strain, VE estimates were 12%-79% lower among children aged ≥12 months relative to those 6-11 months of age. The lower VE for G3P[8] was related to the higher mean age of cases (17.3 months) compared with the G2P[4] strains (11.9 months), with a significant trend (R(2)= 0.819;P< .001) of declining effectiveness with increasing mean age of the cases. Introduction of RotaTeq did not result in sustained emergence of any particular strain in Nicaragua. Variation in strain-specific effectiveness was due to an age-related decline in effectiveness rather than differences in protection against the observed strains. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

New influenza A virus reassortments have been found in Danish swine in 2011

DEFF Research Database (Denmark)

Breum, Solvej Østergaard; Hjulsager, Charlotte Kristiane; Trebbien, Ramona

2012-01-01

” viruses which have been circulating in Danish pigs since it was found for the first time in 1981. ii) H1N2 reassortant viruses which comprise HA from “avian like” H1N1 and NA from swine H3N2. The reassortant H1N2 virus was discovered in Danish pig for the first time in 2003 and is now well established......In 2011 a passive surveillance for influenza A virus was conducted in Danish swine. Tested samples were clinical samples from affected pigs submitted to the Danish National Veterinary Institute for swine influenza virus detection. In total 713 samples from 276 herds were analysed and about 24......% of the samples were positive for swine influenza virus. All influenza positive samples were tested for the H1N1pdm09 virus by a real time RT-PCR assay specific for the pandemic HA gene and 26% of the samples were positive. Subtyping of 90 samples by sequencing revealed the presence of; i) H1N1 “avian like...

Nanotoxicity: emerging concerns regarding nanomaterial safety and occupational hard metal (WC-Co nanoparticle exposure

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Armstead AL

2016-12-01

Full Text Available Andrea L Armstead,1,2 Bingyun Li1–3 1Department of Orthopaedics, School of Medicine, 2School of Pharmacy, West Virginia University, 3Mary Babb Randolph Cancer Center, Morgantown, WV, USA Abstract: As the number of commercial and consumer products containing engineered nanomaterials (ENMs continually rises, the increased use and production of these ENMs presents an important toxicological concern. Although ENMs offer a number of advantages over traditional materials, their extremely small size and associated characteristics may also greatly enhance their toxic potentials. ENM exposure can occur in various consumer and industrial settings through inhalation, ingestion, or dermal routes. Although the importance of accurate ENM characterization, effective dosage metrics, and selection of appropriate cell or animal-based models are universally agreed upon as important factors in ENM research, at present, there is no “standardized” approach used to assess ENM toxicity in the research community. Of particular interest is occupational exposure to tungsten carbide cobalt (WC-Co “dusts,” composed of nano- and micro-sized particles, in hard metal manufacturing facilities and mining and drilling industries. Inhalation of WC-Co dust is known to cause “hard metal lung disease” and an increased risk of lung cancer; however, the mechanisms underlying WC-Co toxicity, the inflammatory disease state and progression to cancer are poorly understood. Herein, a discussion of ENM toxicity is followed by a review of the known literature regarding the effects of WC-Co particle exposure. The risk of WC-Co exposure in occupational settings and the updates of in vitro and in vivo studies of both micro- and nano-WC-Co particles are discussed. Keywords: engineered nanomaterial, occupational exposure, lung disease, cancer, toxicity, particle

Experimental reproduction of rotavirus and Salmonella pullorum ...

African Journals Online (AJOL)

Group A chicks were inoculated with 1 X 106 pfu/ml of rotavirus, group B chicks were inoculated with 1 X 106 cfu/ml of Salmonella pullorum, group C chicks were inoculated with 1 X 106 pfu/ml of rotavirus and 1 X 106 cfu/ml of Salmonella pullorum, while group D birds were given 1ml of PBS alone. Birds in all groups were ...

Estimates of economic burden of providing inpatient care in childhood rotavirus gastroenteritis from Malaysia.

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Lee, Way Seah; Poo, Muhammad Izzuddin; Nagaraj, Shyamala

2007-12-01

To estimate the cost of an episode of inpatient care and the economic burden of hospitalisation for childhood rotavirus gastroenteritis (GE) in Malaysia. A 12-month prospective, hospital-based study on children less than 14 years of age with rotavirus GE, admitted to University of Malaya Medical Centre, Kuala Lumpur, was conducted in 2002. Data on human resource expenditure, costs of investigations, treatment and consumables were collected. Published estimates on rotavirus disease incidence in Malaysia were searched. Economic burden of hospital care for rotavirus GE in Malaysia was estimated by multiplying the cost of each episode of hospital admission for rotavirus GE with national rotavirus incidence in Malaysia. In 2002, the per capita health expenditure by Malaysian Government was US$71.47. Rotavirus was positive in 85 (22%) of the 393 patients with acute GE admitted during the study period. The median cost of providing inpatient care for an episode of rotavirus GE was US$211.91 (range US$68.50-880.60). The estimated average cases of children hospitalised for rotavirus GE in Malaysia (1999-2000) was 8571 annually. The financial burden of providing inpatient care for rotavirus GE in Malaysian children was estimated to be US$1.8 million (range US$0.6 million-7.5 million) annually. The cost of providing inpatient care for childhood rotavirus GE in Malaysia was estimated to be US$1.8 million annually. The financial burden of rotavirus disease would be higher if cost of outpatient visits, non-medical and societal costs are included.

Expression and characterization of a novel truncated rotavirus VP4 for the development of a recombinant rotavirus vaccine.

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Li, Yijian; Xue, Miaoge; Yu, Linqi; Luo, Guoxing; Yang, Han; Jia, Lianzhi; Zeng, Yuanjun; Li, Tingdong; Ge, Shengxiang; Xia, Ningshao

2018-04-12

The outer capsid protein VP4 is an important target for the development of a recombinant rotavirus vaccine because it mediates the attachment and penetration of rotavirus. Due to the poor solubility of full-length VP4, VP8 was explored as candidate rotavirus vaccines in the past years. In previous studies, it has been found that the N-terminal truncated VP8 protein, VP8-1 (aa26-231), could be expressed in soluble form with improved immunogenicity compared to the core of VP8 (aa65-223). However, this protein stimulated only a weak immune response when aluminum hydroxide was used as an adjuvant. In addition, it should be noted that the protective efficacy of VP4 was higher than that of VP8 and VP5. In this study, it was found that when the N-terminal 25 amino acids were deleted, the truncated VP4 ∗ (aa26-476) containing VP8 and the stalk domain of VP5 could be expressed in soluble form in E. coli and purified to homogeneous trimers. Furthermore, the truncated VP4 could induce high titers of neutralizing antibodies when aluminum adjuvant was used and conferred high protective efficacy in reducing the severity of diarrhea and rotavirus shedding in stools in animal models. The immunogenicity of the truncated VP4 was significantly higher than that of VP8 ∗ and VP5 ∗ alone. Taken together, the truncated VP4 ∗ (aa26-476), with enhanced immunogenicity and immunoprotectivity, could be considered as a viable candidate for further development and has the potential to become a parenterally administered rotavirus vaccine. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characteristics of Rotavirus Diarrhea in Hospitalized Children in Kosovo

Science.gov (United States)

Ismaili-Jaha, Vlora; Shala, Muje; Azemi, Mehmedali; Hoxha-Kamberi, Teuta; Avdiu, Muharrem; Spahiu, Shqipe; Jaha, Luan

2014-01-01

Background: Diarrhea is a leading cause of child mortality worldwide. Rotavirus is one of the most common causes of severe diarrhea and dehydration in children. Authors reviewed epidemiological and clinical data of the rotavirus diarrhea in Kosovo. Methods: This is a prospective study carried between January 1st and December 31st 2011. All data, comprising demographics, nutrition, clinical presentation, laboratory findings, management and outcome of the rotavirus diarrhea are collected on the specially designed form. Results: 116 children with rotavirus diarrhea are included in the study. The majority boys (74.4%) and children aged 0 – 12 months (82.75%). Mean age of children in the study was 16.38 months. Almost every third child in the study was hypotrophic (29.2%). More than half of the infants (55.2%) were on mixed food, somewhat more than every third was breast feeding (36.45%), and every twelfth (8.33%) was on artificial milk (animal or formula). Apart from diarrhea, present in all patients, vomiting (97.41%) and fever (43.96%) were characteristics of the clinical presentation of the diarrhea. Two thirds of the children had mild grade dehydration (70.7%). All patients recovered with no sequels. Conclusion: Rotavirus continues to be responsible for a significant portion of acute diarrhea in Kosovo. Clinical features, epidemiological data and the agglutination test are safe enough to establish the diagnosis. Treated correctly rotavirus diarrhea has a favorable outcome. PMID:25568634

Human rotavirus strain Wa downregulates NHE1 and NHE6 expressions in rotavirus-infected Caco-2 cells.

Science.gov (United States)

Chen, Honglang; Song, Lijun; Li, Guixian; Chen, Wenfeng; Zhao, Shumin; Zhou, Ruoxia; Shi, Xiaoying; Peng, Zhenying; Zhao, Wenchang

2017-06-01

Rotavirus (RV) is the most common cause of severe gastroenteritis and fatal dehydration in human infants and neonates of different species. However, the pathogenesis of rotavirus-induced diarrhea is poorly understood. Secretory diarrhea caused by rotavirus may lead to a combination of excessive secretion of fluid and electrolytes into the intestinal lumen. Fluid absorption in the small intestine is driven by Na + -coupled transport mechanisms at the luminal membrane, including Na + /H + exchanger (NHE). Here, we performed qRT-PCR to detect the transcription of NHEs. Western blotting was employed for protein detection. Furthermore, immunocytochemistry was used to validate the NHE's protein expression. Finally, intracellular Ca 2+ concentration was detected by confocal laser scanning microscopy. The results demonstrated that the NHE6 mRNA and protein expressed in the human colon adenocarcinoma cell line (Caco-2). Furthermore, RV-Wa induced decreased expression of the NHE1 and NHE6 in Caco-2 cell in a time-dependent manner. In addition, intracellular Ca 2+ concentration in RV-Wa-infected Caco-2 cells was higher than that in the mock-infected cells. Furthermore, RV-Wa also can downregulate the expression of calmodulin (CaM) and calmodulin kinase II (CaMKII) in Caco-2 cells. These findings provides important insights into the mechanisms of rotavirus-induced diarrhea. Further studies on the underlying pathophysiological mechanisms that downregulate NHEs in RV-induced diarrhea are required.

Diversity and zoonotic potential of rotaviruses in swine and cattle across Europe

DEFF Research Database (Denmark)

Midgley, Sofie E.; Bányai, Krisztián; Buesa, Javier

2012-01-01

Group A rotaviruses can infect both humans and animals. Individual rotavirus strains can occasionally cross species barriers and might hereby contribute to the emergence of new genotypes in heterologous hosts. The incidence and impact of zoonotic rotavirus are not well defined, and one reason...... for this is a lack of data about strains circulating in suspected reservoir animal hosts. In this study we report the incidence, genetic diversity, and molecular epidemiology of rotaviruses detected in domestic cattle and swine in 6 European countries. From 2003 to 2007, 1101 and more than 2000 faecal specimens were...... collected from swine and cattle, both healthy and diarrhoeic, and tested for rotaviruses. Viruses from positive stools were genotyped and a subset of strains was characterized by nucleotide sequencing and phylogenetic analysis of the VP7 (G) and VP4 (P) genes. Rotaviruses were detected in 43% of bovine...

NEW PREVENTION OPPORTUNITIES OF INFECTIOUS DISEASES. VACCINATION AGAINST ROTAVIRUS

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T. A. Grechukha

2013-01-01

Full Text Available The article covers the problem of the burden of rotavirus disease. Rotavirus infection is the leading cause of mortality among children under 5 years of age and is a major problem for a public healthcare. The world is actively engaged in the prevention of rotavirus infection since 2005. There is a lot of data on the efficacy and safety of this vaccine. Different foreign investigations have shown the herd immunity of the vaccine. The authors present data about the effectiveness and safety of vaccines, established during clinical studies of the foreign scientists.

Effects of wastewater sludge and its detergents on the stability of rotavirus

Energy Technology Data Exchange (ETDEWEB)

Ward, R.L. (Sandia Labs., Albuquerque, NM); Ashley, C.S.

1980-06-01

Wastewater sludge reduced the heat required to inactivate rotavirus SA-11, and ionic detergents were identified as the sludge components responsible for this effect. A similar result was found previously with reovirus. The quantitative effects of individual ionic detergents on rotavirus and reovirus were very different, and rotavirus was found to be extremely sensitive to several of these detergents. However, neither virus was destabilized by nonionic detergents. On the contrary, rotavirus was stabilized by a nonionic detergent against the potent destabilizing effects of the ionic detergent sodium dodecyl sulfate. The destabilizing effects of both cationic and anionic detergents on rotavirus were greatly altered by changes in the pH of the medium.

Oral live attenuated human rotavirus vaccine (RotarixTM offers sustained high protection against severe G9P[8] rotavirus gastroenteritis during the first two years of life in Brazilian children

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Maria Cleonice A Justino

2012-11-01

Full Text Available In a large Phase III trial conducted in 10 Latin American countries, the safety and efficacy of the live attenuated monovalent rotavirus vaccine RIX4414 was evaluated in 15,183 healthy infants followed up during the first two years of life. Belém was the only site in Brazil included in this multicentre trial. The study in Belém included a subset of 653 infants who were followed up until 24 months of age for protection against severe rotavirus gastroenteritis. These subjects were randomly assigned in a 1:1 ratio to receive two doses of vaccine (n = 328 or two doses of placebo (n = 325 at approximately two and four months of age. Of the 653 enrolled infants, 23 dropped out during the study period. For the combined two-year period, the efficacy of RIX4414 was 72.3% [95% confidence interval (CI 37.5-89.1%] against severe rotavirus-related gastroenteritis, reaching a protection rate of 81.8% (95% CI 36.4-96.6% against circulating wild-type G9 rotavirus strains. It is concluded that two doses of RIX4414 are highly efficacious against severe rotavirus gastroenteritis in Belém during the first two years of life and provide high protection against the worldwide emergence and spread of G9P[8] strains.

Identification of Rotavirus VP6-Specific CD4+ T Cell Epitopes in a G1P[8] Human Rotavirus-Infected Rhesus Macaque

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Wei Zhao

2008-01-01

Full Text Available A non-human primate model was used to evaluate its potential for identification of rotavirus viral protein 6 (VP6 CD4+ T cell epitopes. Four juvenile rhesus macaques were inoculated with a mixed inoculum (G1P[8] and G9P[8] of human rotaviruses. Infection accompanied by G1P[8] shedding was achieved in the two macaques that had no rotavirus immunoglobulin A (IgA in plasma. To measure the interferon gamma (IFN-γ and tumor necrosis factor (TNF anti-viral cytokines produced by peripheral CD4+ cells that recognize VP6 epitopes, whole blood cells from one infected macaque were stimulated in vitro with VP6 peptides. Stimulation with peptide pools derived from the simian rotavirus VP6 161–395 region revealed reactivity of CD4+ T cells with the VP6 281–331 domain. A VP6 301–315 region was identified as the epitope responsible for IFN-γ production while a broader VP6 293–327 domain was linked to TNF production. These results suggest that human rotavirus-infected macaques can be used for identification of additional epitopes and domains to address specific questions related to the development of pediatric vaccines.

First study conducted in Northern India that identifies group C rotavirus as the etiological agent of severe diarrhea in children in Delhi.

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Tiku, Vasundhara Razdan; Jiang, Baoming; Kumar, Praveen; Aneja, Satender; Bagga, Arvind; Bhan, Maharaj Kishen; Ray, Pratima

2017-05-30

Group C Rotavirus (RVC) is an enteric pathogen responsible for acute gastroenteritis in children and adults globally. At present there are no surveillance studies on group C Rotaviruses in India and therefore their prevalence in India remains unknown. The present study aimed to evaluate group C rotavirus infection among rotavirus (N = 180) by Enzyme immunoassay were screened for group C rotavirus by RT-PCR with VP6, VP7 and VP4 gene specific primers. The PCR products were further sequenced (VP6, VP7, VP4) and analyzed to ascertain their origin and G and P genotypes. Six out of 180 (group A rotavirus negative) samples were found positive for group C rotavirus by VP6 gene specific RT-PCR, of which 3 were also found positive for VP7 and VP4 genes. Phylogenetic analysis of VP7 and VP4 genes of these showed them to be G4 and P[2] genotypes. Overall, the nucleotide sequence data (VP6, VP7 and VP4) revealed a close relationship with the human group C rotavirus with no evidence of animal ancestry. Interestingly, the nucleotide sequence analysis of various genes also indicated differences in their origin. While the identity matrix of VP4 gene (n = 3) showed high amino acid sequence identity (97.60 to 98.20%) with Korean strain, the VP6 gene (n = 6) showed maximum identity with Nigerian strain (96.40 to 97.60%) and VP7 gene (n = 3) with Bangladeshi and USA strains. This is true for all analyzed samples. Our study demonstrated the group C rotavirus as the cause of severe diarrhea in young children in Delhi and provides insights on the origin of group C rotavirus genes among the local strains indicating their source of transmission. Our study also highlights the need for a simple and reliable diagnostic test that can be utilized to determine the disease burden due to group C rotavirus in India.

Economic impact of a rotavirus vaccination program in Mexico Impacto económico de un programa de vacunación contra rotavirus en México

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Dagna Constenla

2009-06-01

Full Text Available OBJECTIVES: To evaluate the cost and benefits of a national rotavirus childhood vaccination program in Mexico. METHODS: A decision-analysis model was designed to take the Mexican health care system's perspective on a comparison of two alternatives: to vaccinate against rotavirus or not. Using published, national data, estimations were calculated for the rotavirus illnesses, deaths, and disability-adjusted life years (DALYs that would be averted and the incremental costeffectiveness ratios (US$/DALY of a hypothetical annual birth cohort of 2 285 000 children, with certain assumptions made for cost, coverage, and efficacy rates. RESULTS: With 93% coverage and a vaccine price of US$ 16 per course (2 doses, a rotavirus vaccination program in Mexico would prevent an estimated 651 deaths (or 0.28 deaths per 1 000 children; 13 833 hospitalizations (6.05 hospitalizations per 1 000 children; and 414 927 outpatient visits (182 outpatient visits per 1 000 children for rotavirus-related acute gastroenteritis (AGE. Vaccination is likely to reduce the economic burden of rotavirus AGE in Mexico by averting US$ 14 million (71% of the overall health care burden. At a vaccine price of US$ 16 per course, the cost-effectiveness ratio would be US$ 1 139 per DALY averted. A reduction in the price of the rotavirus vaccination program (US$ 8 per course would yield a lower incremental cost-effectiveness ratio of US$ 303 per DALY averted. CONCLUSIONS: A national rotavirus vaccination program in Mexico is projected to reduce childhood incidence and mortality and to be highly cost-effective based on the World Health Organization's thresholds for cost-effective interventions.OBJETIVOS: Evaluar el costo y los beneficios de un programa nacional de vacunación infantil contra el rotavirus en México. MÉTODOS: Se diseñó un modelo de análisis de decisión, desde la perspectiva del sistema de salud mexicano, para comparar dos alternativas: vacunar contra el rotavirus o no

Protein-energy malnutrition alters IgA responses to rotavirus vaccination and infection but does not impair vaccine efficacy in mice.

Science.gov (United States)

Maier, Elizabeth A; Weage, Kristina J; Guedes, Marjorie M; Denson, Lee A; McNeal, Monica M; Bernstein, David I; Moore, Sean R

2013-12-17

Conflicting evidence links malnutrition to the reduced efficacy of rotavirus vaccines in developing countries, where diarrhea and undernutrition remain leading causes of child deaths. Here, we adapted mouse models of rotavirus vaccination (rhesus rotavirus, RRV), rotavirus infection (EDIM), and protein-energy malnutrition (PEM) to test the hypothesis that undernutrition reduces rotavirus vaccine immunogenicity and efficacy. We randomized wild type Balb/C dams with 3-day-old pups to a control diet (CD) or an isocaloric, multideficient regional basic diet (RBD) that produces PEM. At 3 weeks of age, we weaned CD and RBD pups to their dams' diet and subrandomized weanlings to receive a single dose of either live oral rotavirus vaccine (RRV) or PBS. At 6 weeks of age, we orally challenged all groups with murine rotavirus (EDIM). Serum and stool specimens were collected before and after RRV and EDIM administration to measure viral shedding and antibody responses by ELISA. RBD pups and weanlings exhibited significant failure to thrive compared to age-matched CD mice (Pvaccination induced higher levels of serum anti-RV IgA responses in RBD vs. CD mice (PVaccination protected CD and RBD mice equally against EDIM infection, as measured by viral shedding. In unvaccinated RBD mice, EDIM shedding peaked 1 day earlier (Pvaccination (Pvaccination mitigated stool IgA responses to EDIM more in CD vs. RBD mice (Pvaccination and infection, undernutrition does not impair rotavirus vaccine efficacy nor exacerbate infection in this mouse model of protein-energy malnutrition. Alternative models are needed to elucidate host-pathogen factors undermining rotavirus vaccine effectiveness in high-risk global settings. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

Trends in diarrhea hospitalizations among infants at three hospitals in Tanzania before and after rotavirus vaccine introduction.

Science.gov (United States)

Lyamuya, Faraja; Michael, Fausta; Jani, Bhavin; Fungo, Yohana; Chambo, Alfred; Chami, Inviolatha; Bulali, Regina; Mpamba, Amina; Cholobi, Happy; Kallovya, Dotto; Kamugisha, Christopher; Mwenda, Jason M; Cortese, Margaret M

2018-04-11

The Tanzania Ministry of Health introduced monovalent human rotavirus vaccine in January 2013, to be administered at ages 6 and 10 weeks. Data suggest there was high vaccine uptake. We used hospital ward registers from 3 hospitals to examine trends in diarrhea hospitalizations among infants before and after vaccine introduction. Ward registers from Dodoma Regional Referral Hospital (Central Tanzania), and two hospitals in Mbeya (Southwest area), Mbeya Zonal Referral Hospital and Mbalizi Hospital, were used to tally admissions for diarrhea among children by age group, month and year. Rotavirus surveillance had started at these hospitals in early 2013; the proportion of infants enrolled and rotavirus-EIA positive were examined by month to determine peak periods of rotavirus disease post-vaccine introduction. Registers were available for 2-4 prevaccine years and 2-3 post introduction years. At Dodoma Regional Referral Hospital, compared with the mean of 2011 and 2012, diarrhea hospitalizations among infants were 26% lower in 2015 and 58% lower in 2016. The diarrhea peak shifted later in the year first by 1 and then by 2-3 months from prevaccine. At the Mbeya hospitals, the number of diarrhea admissions in prevaccine period varied substantially by year. At Mbeya Referral Hospital, diarrhea hospitalizations among infants were lower by 25-37% in 2014 and 11-26% in 2015, while at Mbalizi Hospital, these hospitalizations were 4% lower in 2014 and 14% higher in 2015. Rotavirus testing data demonstrated a lowering of the prevaccine peak, a shift in timing of the peak months and indicated that other diarrheal peaks in post-introduction years were not due to rotavirus. In this ecological evaluation, total diarrhea hospitalizations among infants were lower (≥25% lower in ≥1 year) following introduction in 2 of 3 hospitals. There are challenges in using ward registers to ascertain possible impact of rotavirus vaccine introduction on trends in hospitalizations for

Rotavirus Vaccine Response Correlates with the Infant Gut Microbiota Composition in Pakistan

NARCIS (Netherlands)

Harris, Vanessa; Ali, Asad; Fuentes, Susana; Korpela, Katri; Kazi, Momin; Tate, Jacqueline; Parashar, Umesh; Wiersinga, W. Joost; Giaquinto, Carlo; de Weerth, Carolina; de Vos, Willem M.

2017-01-01

Background Rotavirus (RV) is the leading cause of diarrhea-related death in children worldwide, and ninety-five percent of rotavirus deaths occur in Africa and Asia. Rotavirus vaccines (RVV) can dramatically reduce RV deaths, but have low efficacy in low-income settings where they are most needed.

ROTAVIRUS INFECTION. HOW TO REALLY PROTECT CHILDREN FROM SEVERE GASTROENTERITIS?

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T. A. Grechukha

2013-01-01

Full Text Available According to the statistics of the recent 5 years, the share of rotavirus gastroenterites is 44-47% of all acute intestinal infections in children under 5 years of age in the Russian Federation. Up to 5% of mortality rate in children under 5 years of age is connected with rotavirus gastroenteritis. Rotavirus gastroenteritis takes an especially severe course in children of 6-24 months of age. The only reliable method of preventing this infection is vaccination. The authors present information on the rotavirus strains dominant in Russia and abroad, efficacy and safety of immunization with a pentavalent vaccine and the recommended schemes of its administration. This vaccine is registered in the Russian Federation; it is to be first used in the nearest future.

Quantifying the risk of pandemic influenza virus evolution by mutation and re-assortment.

Science.gov (United States)

Reperant, Leslie A; Grenfell, Bryan T; Osterhaus, Albert D M E

2015-12-08

Large outbreaks of zoonotic influenza A virus (IAV) infections may presage an influenza pandemic. However, the likelihood that an airborne-transmissible variant evolves upon zoonotic infection or co-infection with zoonotic and seasonal IAVs remains poorly understood, as does the relative importance of accumulating mutations versus re-assortment in this process. Using discrete-time probabilistic models, we determined quantitative probability ranges that transmissible variants with 1-5 mutations and transmissible re-assortants evolve after a given number of zoonotic IAV infections. The systematic exploration of a large population of model parameter values was designed to account for uncertainty and variability in influenza virus infection, epidemiological and evolutionary processes. The models suggested that immunocompromised individuals are at high risk of generating IAV variants with pandemic potential by accumulation of mutations. Yet, both immunocompetent and immunocompromised individuals could generate high viral loads of single and double mutants, which may facilitate their onward transmission and the subsequent accumulation of additional 1-2 mutations in newly-infected individuals. This may result in the evolution of a full transmissible genotype along short chains of contact transmission. Although co-infection with zoonotic and seasonal IAVs was shown to be a rare event, it consistently resulted in high viral loads of re-assortants, which may facilitate their onward transmission among humans. The prevention or limitation of zoonotic IAV infection in immunocompromised and contact individuals, including health care workers, as well as vaccination against seasonal IAVs-limiting the risk of co-infection-should be considered fundamental tools to thwart the evolution of a novel pandemic IAV by accumulation of mutations and re-assortment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Influence of oral polio vaccines on performance of the monovalent and pentavalent rotavirus vaccines.

Science.gov (United States)

Patel, Manish; Steele, A Duncan; Parashar, Umesh D

2012-04-27

In recent years, two live, oral rotavirus vaccines have been successfully tested in developing and industrialized countries, and both vaccines are now recommended by the World Health Organization for all children worldwide. Both immunogenicity and efficacy of these rotavirus vaccines has been lower in developing compared to industrialized settings. We reviewed the data on the effect of trivalent OPV on the immunogenicity and efficacy of two rotavirus vaccines currently recommended by the WHO. While rotavirus vaccines have not affected immune responses to OPV, in general, the immune responses (i.e., antibody levels) to rotavirus vaccination were lower when rotavirus vaccines were co-administered with OPV. Limited data suggests that the interference is greater after the first dose of OPV, presumably because the first dose is associated with greatest intestinal replication of vaccine polio virus strains, and this interference is largely overcome with subsequent rotavirus vaccine doses. Despite the lower immunogenicity, one large efficacy study in middle income Latin American countries showed no decrease in protective efficacy of rotavirus vaccine in infants receiving concurrent OPV. While these data are encouraging and support simultaneous administration of rotavirus vaccines and OPV, additional evidence should be gathered as rotavirus vaccines are used more widely in developing country settings, where OPV is routinely used, rather than inactivated polio vaccine. Published by Elsevier Ltd.

Rotavirus vaccine response correlates with the infant gut microbiota composition in Pakistan

NARCIS (Netherlands)

Harris, Vanessa C.; Ali, Asad; Fuentes, Susana; Korpela, Katri; Kazi, Momin; Tate, Jacqueline; Parashar, Umesh; Wiersinga, W.J.; Giaquinto, Carlo; Weerth, de Carolina; Vos, de Willem M.

2017-01-01

Rotavirus (RV) is the leading cause of diarrhea-related death in children worldwide and ninety-five percent of rotavirus deaths occur in Africa and Asia. Rotavirus vaccines (RVV) can dramatically reduce RV deaths, but have low efficacy in low-income settings where they are most needed. The

Microstructure and hardness of WC-Co particle reinforced iron matrix surface composite

Directory of Open Access Journals (Sweden)

Zhang Peng

2013-11-01

Full Text Available In this study, a high Cr cast iron surface composite material reinforced with WC-Co particles 2-6 mm in size was prepared using a pressureless sand mold infiltration casting technique. The composition, microstructure and hardness were determined by means of energy dispersive spectrometry (EDS, electron probe microanalysis (EPMA, scanning electron microscope (SEM and Rockwell hardness measurements. It is determined that the obtained composite layer is about 15 mm thick with a WC-Co particle volumetric fraction of ~38%. During solidification, interface reaction takes place between WC-Co particles and high chromium cast iron. Melting and dissolving of prefabricated particles are also found, suggesting that local Co melting and diffusion play an important role in promoting interface metallurgical bonding. The composite layer is composed of ferrite and a series of carbides, such as (Cr, W, Fe23C6, WC, W2C, M6C and M12C. The inhomogeneous hardness in the obtained composite material shows a gradient decrease from the particle reinforced metal matrix composite layer to the matrix layer. The maximum hardness of 86.3 HRA (69.5 HRC is obtained on the particle reinforced surface, strongly indicating that the composite can be used as wear resistant material.

Molecular characterization of group A rotaviruses detected in children with gastroenteritis in Ireland in 2006-2009.

LENUS (Irish Health Repository)

Cashman, O

2012-02-01

SUMMARYCommunity and hospital-acquired cases of human rotavirus are responsible for millions of gastroenteritis cases in children worldwide, chiefly in developing countries, and vaccines are now available. During surveillance activity for human rotavirus infections in Ireland, between 2006 and 2009, a total of 420 rotavirus strains were collected and analysed. Upon either PCR genotyping and sequence analysis, a variety of VP7 (G1-G4 and G9) and VP4 (P[4], P[6], P[8] and P[9]) genotypes were detected. Strains G1P[8] were found to be predominant throughout the period 2006-2008, with slight fluctuations seen in the very limited samples available in 2008-2009. Upon either PCR genotyping and sequence analysis of selected strains, the G1, G3 and G9 viruses were found to contain E1 (Wa-like) NSP4 and I1 VP6 genotypes, while the analysed G2 strains possessed E2 NSP4 and I2 VP6 genotypes, a genetic make-up which is highly conserved in the major human rotavirus genogroups Wa- and Kun-like, respectively. Upon sequence analysis of the most common VP4 genotype, P[8], at least two distinct lineages were identified, both unrelated to P[8] Irish rotaviruses circulating in previous years, and more closely related to recent European humans rotaviruses. Moreover, sequence analysis of the VP7 of G1 rotaviruses revealed the onset of a G1 variant, previously unseen in the Irish population.

Correlates of protection against human rotavirus disease and the factors influencing protection in low-income settings.

Science.gov (United States)

Clarke, E; Desselberger, U

2015-01-01

Rotaviruses (RV) are the leading cause of gastroenteritis in infants and children worldwide and are associated with high mortality predominately in low-income settings. The virus is classified into G and P serotypes and further into P genotypes based on differences in the surface-exposed proteins VP7 and VP4, respectively. Infection results in a variable level of protection from subsequent reinfection and disease. This protection is predominantly homotypic in some settings, whereas broader heterotypic protection is reported in other cohorts. Two antigenically distinct oral RV vaccines are licensed and are being rolled out widely, including in resource-poor setting, with funding provided by the GAVI alliance. First is a monovalent vaccine derived from a live-attenuated human RV strain, whereas the second is a pentavalent bovine-human reassortment vaccine. Both vaccines are highly efficacious in high-income settings, but greatly reduced levels of protection are reported in low-income countries. Here, the current challenges facing mucosal immunologists and vaccinologists aiming to define immunological correlates and to understand the variable levels of protection conferred by these vaccines in humans is considered. Such understanding is critical to maximize the public health impact of the current vaccines and also to the development of the next generation of RV vaccines, which are needed.

The Particle Shape of WC Governing the Fracture Mechanism of Particle Reinforced Iron Matrix Composites.

Science.gov (United States)

Li, Zulai; Wang, Pengfei; Shan, Quan; Jiang, Yehua; Wei, He; Tan, Jun

2018-06-11

In this work, tungsten carbide particles (WC p , spherical and irregular particles)-reinforced iron matrix composites were manufactured utilizing a liquid sintering technique. The mechanical properties and the fracture mechanism of WC p /iron matrix composites were investigated theoretically and experimentally. The crack schematic diagram and fracture simulation diagram of WC p /iron matrix composites were summarized, indicating that the micro-crack was initiated both from the interface for spherical and irregular WC p /iron matrix composites. However, irregular WC p had a tendency to form spherical WC p . The micro-cracks then expanded to a wide macro-crack at the interface, leading to a final failure of the composites. In comparison with the spherical WC p , the irregular WC p were prone to break due to the stress concentration resulting in being prone to generating brittle cracking. The study on the fracture mechanisms of WC p /iron matrix composites might provide a theoretical guidance for the design and engineering application of particle reinforced composites.

Frequency of Rotavirus Infection among Children with Diarrhea in ...

African Journals Online (AJOL)

Background: Rotaviruses are the major cause of gastroenteritis and diarrhea in infants and young children worldwide. Basic epidemiological data concerning rotaviruses among infants and children are necessary for health planners and care providers in Sudan. Method: Cross-sectional study was conducted at Omdurman ...

Rotavirus disease course among immunocompromised patients : 5-year observations from a tertiary care medical centre

NARCIS (Netherlands)

Bruijning-Verhagen, P; Nipshagen, M D; Graaf, H.; Bonten, M J M

2017-01-01

Rotavirus (RV) is highly endemic inside and outside hospital-settings. Immunocompromised children and adults are at risk of complicated rotavirus gastroenteritis (RVGE), but general rotavirus disease severity in this group remains poorly described and rotavirus testing is not routinely performed

Dynamic modeling of cost-effectiveness of rotavirus vaccination, Kazakhstan.

Science.gov (United States)

Freiesleben de Blasio, Birgitte; Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children vaccine cost at vaccination program costs would be entirely offset. To further evaluate efficacy of a vaccine program, benefits of indirect protection conferred by vaccination warrant further study.

Real-World Effectiveness of Pentavalent Rotavirus Vaccine Among Bedouin and Jewish Children in Southern Israel.

Science.gov (United States)

Leshem, Eyal; Givon-Lavi, Noga; Tate, Jacqueline E; Greenberg, David; Parashar, Umesh D; Dagan, Ron

2016-05-01

Pentavalent rotavirus vaccine (RV5) was introduced into the Israeli National Immunization Program in January 2011. We determined RV5 vaccine effectiveness (VE) in southern Israel, a region characterized by 2 distinct populations: Bedouins living in a low- to middle-income, semirural setting, and Jews living in a high-income, urban setting. We enrolled vaccine-eligible children who visited the emergency department (ED) or were hospitalized due to acute gastroenteritis (AGE) during the first 3 rotavirus seasons after RV5 vaccine introduction (2011-2013). Fecal specimens were tested for rotavirus by enzyme immunoassay and genotyped. Vaccination among laboratory-confirmed rotavirus cases was compared with rotavirus-negative AGE controls. Regression models were used to calculate VE estimates by age, clinical setting, and ethnicity. Of 515 enrolled patients, 359 (70%) were Bedouin. Overall, 185 (36%) patients were rotavirus positive; 79 of 119 (66%) were G1P[8] genotype. The adjusted VE for a full 3-dose course of RV5 against ED visit or hospitalization was 63% (95% confidence interval [CI], 38%-78%). RV5 provided G1P[8] genotype-specific effectiveness of 78% (95% CI, 58%-88%). By age, RV5 VE was 64% (95% CI, 21%-84%) and 71% (95% CI, 39%-86%) among children aged 6-11 months and 12-23 months, respectively. By clinical setting, RV5 VE was 59% (95% CI, 23%-78%) against hospitalization, and 67% (95% CI, 11%-88%) against ED visit. The adjusted VE of a full RV5 course among Bedouin children was 62% (95% CI, 29%-79%). RV5 significantly protected against rotavirus-associated ED visits and hospitalizations in a diverse population of vaccine-eligible children living in southern Israel. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Rotavirus vaccine effectiveness in low-income settings: An evaluation of the test-negative design.

Science.gov (United States)

Schwartz, Lauren M; Halloran, M Elizabeth; Rowhani-Rahbar, Ali; Neuzil, Kathleen M; Victor, John C

2017-01-03

The test-negative design (TND), an epidemiologic method currently used to measure rotavirus vaccine (RV) effectiveness, compares the vaccination status of rotavirus-positive cases and rotavirus-negative controls meeting a pre-defined case definition for acute gastroenteritis. Despite the use of this study design in low-income settings, the TND has not been evaluated to measure rotavirus vaccine effectiveness. This study builds upon prior methods to evaluate the use of the TND for influenza vaccine using a randomized controlled clinical trial database. Test-negative vaccine effectiveness (VE-TND) estimates were derived from three large randomized placebo-controlled trials (RCTs) of monovalent (RV1) and pentavalent (RV5) rotavirus vaccines in sub-Saharan Africa and Asia. Derived VE-TND estimates were compared to the original RCT vaccine efficacy estimates (VE-RCTs). The core assumption of the TND (i.e., rotavirus vaccine has no effect on rotavirus-negative diarrhea) was also assessed. TND vaccine effectiveness estimates were nearly equivalent to original RCT vaccine efficacy estimates. Neither RV had a substantial effect on rotavirus-negative diarrhea. This study supports the TND as an appropriate epidemiologic study design to measure rotavirus vaccine effectiveness in low-income settings. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Hospitalization of childhood rotavirus infection from Kuala Lumpur, Malaysia.

Science.gov (United States)

Lee, W S; Veerasingam, P D; Goh, A Y T; Chua, K B

2003-01-01

To determine the epidemiology of rotavirus gastroenteritis in children admitted to an urban hospital in a developing country from South-East Asia. Retrospective review of cases of acute gastroenteritis admitted to the children's ward of the University of Malaya Medical Centre, Kuala Lumpur, Malaysia, between 1996 and 1999. During the study period, 333 cases (24%) of 1362 stool samples, obtained from children admitted with acute diarrhoea, were positive for rotavirus. Acute gastroenteritis constituted 8.2%, and rotavirus infection 1.6% of all the paediatric admissions each year. Of the 271 cases analysed, 72% of the affected population were less than 2 years of age. Peak incidence of admissions was between January to March, and September to October. Dehydration was common (92%) but electrolyte disturbances, lactose intolerance (5.2%), prolonged diarrhoea (2.6%) and cow's milk protein intolerance was uncommon. No deaths were recorded. Rotavirus infection was a common cause of childhood diarrhoea that required hospital admission in an urban setting in Malaysia.

Dynamic Modeling of Cost-effectiveness of Rotavirus Vaccination, Kazakhstan

Science.gov (United States)

Flem, Elmira; Latipov, Renat; Kuatbaeva, Ajnagul; Kristiansen, Ivar Sønbø

2014-01-01

The government of Kazakhstan, a middle-income country in Central Asia, is considering the introduction of rotavirus vaccination into its national immunization program. We performed a cost-effectiveness analysis of rotavirus vaccination spanning 20 years by using a synthesis of dynamic transmission models accounting for herd protection. We found that a vaccination program with 90% coverage would prevent ≈880 rotavirus deaths and save an average of 54,784 life-years for children <5 years of age. Indirect protection accounted for 40% and 60% reduction in severe and mild rotavirus gastroenteritis, respectively. Cost per life year gained was US $18,044 from a societal perspective and US $23,892 from a health care perspective. Comparing the 2 key parameters of cost-effectiveness, mortality rates and vaccine cost at

Zoonotic transmission of rotavirus in Denmark; a case report

DEFF Research Database (Denmark)

Midgley, Sofie; Gram, N.; Hjulsager, Charlotte Kristiane

Rotavirus type A infection is a common cause of hospitalisation of children. In addition, almost 30% of diagnosed persons in Denmark are adults. Rotavirus type A infection can also occur in a range of animals, including domestic dogs, cats, cattle, horses, and birds. There is some data suggesting...... direct transmission between animals and humans. Rotavirus genotyping is carried out in Denmark as part of the EUROTAnet vaccine study. In 2006 a total of 180 samples were successfully typed, and to date 85 samples from 2007 have been typed. 19 samples from pigs and 31 samples from cattle (from 2006...... and 2007) have also been typed. For the human samples all common human G types (1-4 and 9), as well the emerging G12 were identified, and were found in combination with the common P types ([4], [6], and [8]). Two samples contained a G8 P[goat] rotavirus (G8 98% identical to bovine G8, 96% identical to goat...

The Control of Rotavirus Gastroenteritis in The United States

Science.gov (United States)

Glass, Roger I.; Parashar, Umesh; Patel, Manish; Tate, Jacqueline; Jiang, Baoming; Gentsch, Jon

2012-01-01

Since 2006, two new vaccines have been licensed to prevent rotavirus, the cause of 20% to 50% of severe acute gastroenteritis in young children worldwide. These vaccines have been implemented in national immunization programs in about 30 high- and middle-income countries, including the United States, and vaccine use has led to substantial decreases in diarrhea-related health care visits. In addition to reductions in diarrhea burden in vaccinated children, decreases have been observed in older, unvaccinated age groups in many settings, suggesting indirect benefits (i.e., herd immunity) from vaccination. Although the efficacy of these oral rotavirus vaccines is expectedly lower in developing countries in Asia and Africa, the public health benefits of vaccination in these settings, where more than 90% of the estimated 453,000 annual deaths from rotavirus occur, are likely to be substantial. Efforts continue to develop alternative rotavirus vaccines that could have a better efficacy and safety profile and may be less expensive. PMID:23303967

Cost-effectiveness analysis of the introduction of rotavirus vaccine in Iran.

Science.gov (United States)

Javanbakht, Mehdi; Moradi-Lakeh, Maziar; Yaghoubi, Mohsen; Esteghamati, Abdoulreza; Mansour Ghanaie, Roxana; Mahmoudi, Sussan; Shamshiri, Ahmad-Reza; Zahraei, Seyed Mohsen; Baxter, Louise; Shakerian, Sareh; Chaudhri, Irtaza; Fleming, Jessica A; Munier, Aline; Baradaran, Hamid R

2015-05-07

Although the mortality from diarrheal diseases has been decreasing dramatically in Iran, it still represents an important proportion of disease burden in children Rotavirus vaccines are among the most effective strategies against diarrheal diseases in specific epidemiological conditions. This study aimed to evaluate the cost-effectiveness of the introduction of rotavirus vaccine (3 doses of pentavalent RotaTeq (RV5)) in Iran, from the viewpoints of Iran's health system and society. The TRIVAC decision support model was used to calculate total incremental costs, life years (LYs) gained, and disability-adjusted life years (DALYs) averted due to the vaccination program. Necessary input data were collected from the most valid accessible sources as well as a systematic review and meta-analysis on epidemiological studies. We used WHO guidelines to estimate vaccination cost. An annual discount rate of 3% was considered for both health gain and costs. A deterministic sensitivity analysis was performed for testing the robustness of the models results. Our results indicated that total DALYs potentially lost due to rotavirus diarrhea within 10 years would be 138,161, of which 76,591 could be prevented by rotavirus vaccine. The total vaccination cost for 10 cohorts was estimated to be US$ 499.91 million. Also, US$ 470.61 million would be saved because of preventing outpatient visits and inpatient admissions (cost-saving from the society perspective). We estimated a cost per DALY averted of US$ 2868 for RV5 vaccination, which corresponds to a highly cost-effective strategy from the government perspective. In the sensitivity analysis, all scenarios tested were still cost-saving or highly cost-effective from the society perspective, except in the least favorable scenario and low vaccine efficacy and disease incidence scenario. Based on the findings, introduction of rotavirus vaccine is a highly cost-effective strategy from the government perspective. Introducing the vaccine to

Modern Views on Rotavirus Infection in Children: Epidemiological and Clinicopathogenetic Features

Directory of Open Access Journals (Sweden)

G.O. Lezhenko

2014-04-01

Full Text Available Based on the analysis of epidemiological, clinical and laboratory data characterizing the course of rotavirus infection in children of Zaporizhya region, there are provided the modern features of the disease. The authors marked dynamic changes in clinical and laboratory parameters of lactase deficiency, which occur during rotavirus infection in infants. The efficiency of Saccharomyces boulardii in complex treatment of rotavirus infection in children is shown.

Efficacy and immunogenicity of live-attenuated human rotavirus vaccine in breast-fed and formula-fed European infants.

Science.gov (United States)

Vesikari, Timo; Prymula, Roman; Schuster, Volker; Tejedor, Juan-C; Cohen, Robert; Bouckenooghe, Alain; Damaso, Silvia; Han, Htay Htay

2012-05-01

Rotavirus is the main cause of severe gastroenteritis and diarrhea in infants and young children less than 5 years of age. Potential impact of breast-feeding on the efficacy and immunogenicity of human rotavirus G1P[8] vaccine was examined in this exploratory analysis. Healthy infants (N = 3994) aged 6-14 weeks who received 2 doses of human rotavirus vaccine/placebo according to a 0-1 or 0-2 month schedule were followed for rotavirus gastroenteritis during 2 epidemic seasons. Rotavirus IgA seroconversion rate (anti-IgA antibody concentration ≥ 20 mIU/mL) and geometric mean concentrations were measured prevaccination and 1-2 months post-dose 2. Vaccine efficacy against any and severe rotavirus gastroenteritis was analyzed according to the infants being breast-fed or exclusively formula-fed at the time of vaccination. Antirotavirus IgA seroconversion rate was 85.5% (95% confidence interval [CI]: 82.4-88.3) in breast-fed and 89.2% (95% CI: 84.2-93) in exclusively formula-fed infants; geometric mean concentrations in the respective groups were 185.8 U/mL (95% CI: 161.4-213.9) and 231.5 U/mL (95% CI: 185.9-288.2). Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season but fell in breast-fed infants in the second rotavirus season. During the combined 2-year efficacy follow-up period, vaccine efficacy against any rotavirus gastroenteritis was 76.2% (95% CI: 68.7-82.1) and 89.8% (95% CI: 77.6-95.9) and against severe rotavirus gastroenteritis 88.4% (95% CI: 81.6-93) and 98.1% (95% CI: 88.2-100) in the breast-fed and exclusively formula-fed infants, respectively. The difference in immunogenicity of human rotavirus vaccine in breast-fed and exclusively formula-fed infants was small. Vaccine efficacy was equally high in breast-fed and exclusively formula-fed children in the first season. Breast-feeding seemed to reduce slightly the efficacy in the second season.

Vacinas contra rotavírus e papilomavírus humano (HPV Vaccines against rotavirus and human papillomavirus (HPV

Directory of Open Access Journals (Sweden)

Alexandre C. Linhares

2006-07-01

-se que a implementação de vacinas de elevada eficácia na prevenção de tumores benignos e malignos causados por alguns tipos de HPV leve a uma queda acentuada das taxas desses tumores, os quais afetam milhões de pessoas em todo o mundo.OBJECTIVE: To briefly review strategies aimed at the development of rotavirus and HPV vaccines, with emphasis on the current status of studies assessing the safety, reactogenicity, immunogenicity and efficacy of recently developed vaccines. SOURCES OF DATA: This review focuses on articles published from 1996 to 2006, mainly those from the last five years, with special emphasis on data obtained from recently completed studies involving a new live attenuated human rotavirus vaccine and a virus-like particle (HPV vaccine. SUMMARY OF THE FINDINGS: Strategies for developing rotavirus vaccines ranged from Jennerian approaches to the new human-derived rotavirus vaccine. Currently, two rotavirus vaccines are recognized as both efficacious and safe: a pentavalent human-bovine reassortant vaccine and a vaccine derived from an attenuated rotavirus of human origin. The second of these has been evaluated in more than 70,000 infants all over the world. Prophylactic vaccines against HPV have been tested in more than 25,000 young individuals around the world. Results from phase II and III clinical studies indicate that such vaccines against the most common types of HPV, those linked to both genital warts and 70% of cervical cancers, are safe and highly efficacious. CONCLUSIONS: A future rotavirus immunization program covering 60 to 80% of infants worldwide is likely to reduce by at least 50% the number of rotavirus-associated hospitalizations and deaths. It is also reasonable to expect that implementation of HPV prophylactic vaccines will reduce the burden of the HPV-related diseases that presently impact millions of people around the world.

Characterization of rotavirus strains detected among children and adults with acute gastroenteritis in Ganozan, Saudi Arabia

International Nuclear Information System (INIS)

Kheyami, Ali M.; Dove, W.; Cunliffe, Nigel A.; Hart, C.A.; Areeshi, Mohammed Y.; Nakagomi, O.

2008-01-01

Objective was to assess the circulating rotavirus strains among hospitalized children and adults in Gizan City. This cross-sectional study was based in 5 hospitals in the Gizan area. Stool samples were collected between November 2004 and March 2005 from sequential patients with acute dehydrating diarrhea. Rotavirus antigen was detected in stool by enzyme-linked immunosorbent assay. The diversity of rotavirus strains was investigated using electropherotyping and reverse transcription-polymerase chain reaction amplification of the VP7 and VP4 genes (G and P genotyping). Rotavirus was detected in 54 of 454 (12%) subjects. The ages of those infected with rotavirus ranged from 15 days to 20 years, with a median age of 36 months. The highest rotavirus detection rate (24%) occurred in children in aged 48-59 months. Overall, 50 (93%) of strains could be assigned both a G- and P- type; G1P (8) was the most frequently detected strain type (n=48, 89%) with one rotavirus each of G2P (4) and G9P (8). Rotavirus strains circulating in Gizan would be well covered by current rotavirus vaccines. Rotavirus serotype G9 has been detected in Saudi Arabia for the first time. Continued surveillance of rotavirus strains is required. (author)

Immunogenicity of rotavirus vaccine (RotarixTM) in infants with environmental enteric dysfunction.

Science.gov (United States)

Mwape, Innocent; Bosomprah, Samuel; Mwaba, John; Mwila-Kazimbaya, Katayi; Laban, Natasha Makabilo; Chisenga, Caroline Cleopatra; Sijumbila, Gibson; Simuyandi, Michelo; Chilengi, Roma

2017-01-01

Deployment of rotavirus vaccines has contributed to significant declines in diarrheal morbidity and mortality globally. Unfortunately, vaccine performance in low-middle income countries (LMICs) is generally lower than in developed countries. The cause for this has been associated with several host and maternal factors including poor water sanitation and hygiene (WASH) status, which are predominant in LMICs. More recently, environmental enteric dysfunction (EED) has specifically been hypothesized to contribute to poor vaccine uptake and response. The aim of this study was to examine the association between serological biomarkers of EED and seroconversion to rotavirus vaccine in Zambian infants. This was a retrospective cohort study of 142 infants who had been fully immunized with Rotarix™, and had known seroconversion status. Seroconversion was defined as 4-fold or more increase in rotavirus-specific IgA titres between pre-vaccination and one month post-dose two vaccination. We performed ELISA assays to assess soluble CD14 (sCD14), Endotoxin Core IgG Antibodies (EndoCAb), intestinal fatty acid binding protein (i-FABP) and Zonulin according to the manufacturers protocols. Generalised linear model with family-poisson, link-log and robust standard error was used to estimate the independent effects of biomarkers on seroconversion adjusting for important cofounders. The median concentration of Zonulin, Soluble CD14, EndoCaB, and IFABP were 209.3 (IQR = 39.7, 395.1), 21.5 (IQR = 21.5, 21.5), 0.3 (IQR = 0.3, 0.3), and 107.7 (IQR = 6.4, 1141.4) respectively. In multivariable analyses adjusting for the independent effect of other biomarkers and confounders (i.e. age of child at vaccination, breast-milk anti-rotavirus IgA, infant serum anti-rotavirus IgG, and IgA seropositivity at baseline), there was strong evidence of about 24% increase in seroconversion due to doubling Zonulin concentration (Adjusted risk ratio (aRR) = 1.24; 95% CI = 1.12 to1.37; pzonulin and IFABP

Changing characteristics of rotavirus diarrhea in children younger than five years in urban Bangladesh.

Directory of Open Access Journals (Sweden)

Mohammad Habibur Rahman Sarker

Full Text Available BACKGROUND: Childhood rotavirus diarrhea is still one of the major public health challenges. The present study aimed to determine changing characteristics of rotavirus diarrhea in under-5 children at two periods of time. METHODS: We enrolled 5,357 under-5 children with rotavirus positive in two different time periods; i 1993-1997 (n = 2,493, and ii 2008-2012 (n = 2,864 considering beginning and ending of two decades. These children were enrolled in the urban Dhaka Hospital of icddr,b. RESULTS: Overall, proportion of rotavirus was about 25% in 1993-97, which was 42% in 2008-12 (68% rise; p5 [38% vs. 35%; aOR-1.32 (95% CI-1.10-1.58] required more intravenous fluid [9% vs. 3%; aOR-4.93 (95% CI-3.19-7.63], had higher co-infection with Shigella [3% vs. 1%; aOR-3.36 (95% CI-1.61-7.03], Vibrio cholerae [4% vs. 1%; aOR-3.70 (95% CI-2.12-6.46]; and ETEC [13% vs. 7%; aOR-2.21 (95% CI-1.65-2.97]; however, significantly lower proportion of them used sanitary toilets [54% vs. 78%; aOR-0.66 (95% CI-0.54-0.80], boiled drinking water [16% vs. 38%; aOR-0.60 (95% CI-0.48-0.74], used antimicrobial at home [63% vs. 82%; aOR-0.56 (95% CI-0.46-0.69] and had some or severe dehydration [18% vs. 34%; aOR-0.15 (95% CI-0.12-0.20] in 1st observation period compared to that of 2nd. CONCLUSION: Proportion of episodes of under-5 rotavirus diarrhea increased over the period. Concomitant changes in host, socio-demographic and clinical characteristics, and co-infections were also observed. Thus, vaccination campaign which is prevailing in private sector should also be introduced in public sector.

Changing Characteristics of Rotavirus Diarrhea in Children Younger than Five Years in Urban Bangladesh

Science.gov (United States)

Sarker, Mohammad Habibur Rahman; Das, Sumon Kumar; Ahmed, Shahnawaz; Ferdous, Farzana; Das, Jui; Farzana, Fahmida Dil; Shahid, Abu S. M. S. B.; Shahunja, K. M.; Afrad, Mokibul Hassan; Malek, Mohammad Abdul; Chisti, Mohammod Jobayer; Bardhan, Pradip Kumar; Hossain, Md Iqbal; Mamun, Abdullah Al; Faruque, Abu S. G.

2014-01-01

Background Childhood rotavirus diarrhea is still one of the major public health challenges. The present study aimed to determine changing characteristics of rotavirus diarrhea in under-5 children at two periods of time. Methods We enrolled 5,357 under-5 children with rotavirus positive in two different time periods; i) 1993-1997 (n = 2,493), and ii) 2008–2012 (n = 2,864) considering beginning and ending of two decades. These children were enrolled in the urban Dhaka Hospital of icddr,b. Results Overall, proportion of rotavirus was about 25% in 1993–97, which was 42% in 2008–12 (68% rise; p5 [38% vs. 35%; aOR-1.32 (95% CI-1.10-1.58)] required more intravenous fluid [9% vs. 3%; aOR-4.93 (95% CI-3.19-7.63)], had higher co-infection with Shigella [3% vs. 1%; aOR-3.36 (95% CI-1.61-7.03)], Vibrio cholerae [4% vs. 1%; aOR-3.70 (95% CI-2.12-6.46)]; and ETEC [13% vs. 7%; aOR-2.21 (95% CI-1.65-2.97)]; however, significantly lower proportion of them used sanitary toilets [54% vs. 78%; aOR-0.66 (95% CI-0.54-0.80)], boiled drinking water [16% vs. 38%; aOR-0.60 (95% CI-0.48-0.74)], used antimicrobial at home [63% vs. 82%; aOR-0.56 (95% CI-0.46-0.69)] and had some or severe dehydration [18% vs. 34%; aOR-0.15 (95% CI-0.12-0.20)] in 1st observation period compared to that of 2nd. Conclusion Proportion of episodes of under-5 rotavirus diarrhea increased over the period. Concomitant changes in host, socio-demographic and clinical characteristics, and co-infections were also observed. Thus, vaccination campaign which is prevailing in private sector should also be introduced in public sector. PMID:25171098

Rotavirus vaccine and diarrhea mortality: quantifying regional variation in effect size

OpenAIRE

Fischer Walker, Christa L; Black, Robert E

2011-01-01

Abstract Background Diarrhea mortality remains a leading cause of child death and rotavirus vaccine an effective tool for preventing severe rotavirus diarrhea. New data suggest vaccine efficacy may vary by region. Methods We reviewed published vaccine efficacy trials to estimate a regional-specific effect of vaccine efficacy on severe rotavirus diarrhea and hospitalizations. We assessed the quality of evidence using a standard protocol and conducted meta-analyses where more than 1 data point ...

Rotavirus vaccines in Israel: Uptake and impact.

Science.gov (United States)

Muhsen, Khitam; Cohen, Daniel

2017-07-03

We present an overview of the impact of universal rotavirus immunization with the pentavalent vaccine, RotaTeq, which was introduced in Israel in 2010. The vaccine is given free of charge at age 2, 4 and 6 months, with an 80% coverage that was shortly achieved during the universal immunization period. Compared to pre-universal immunization years (2008-2010), a reduction of 66-68% in the incidence of rotavirus gastroenteritis (RVGE) hospitalizations was observed in 2011-2015 among children aged 0-23 months in central and northern Israel. In southern Israel a reduction of 80-88% in RVGE hospital visit rate was found among Jewish children aged 0-23 months in 2011-2013. Among Bedouins, the respective decline was 62-75%. A significant reduction of 59% was also observed in RVGE clinic visits, presumably representing less severe illness. Indirect benefit was evident in children aged 24-59 months who were ineligible for universal immunization. Vaccine effectiveness against RVGE hospitalization was estimated at 86% in children aged 6-23 months. Changes in the circulating rotavirus genotypes occurred but the contribution of vaccine induced immune pressure is unclear. Universal rotavirus immunization was followed by an impressive decrease in the burden of RVGE in young children in Israel, likely attributed to good vaccine coverage and effectiveness.

Incorporation of a rotavirus vaccine into the national immunisation schedule in the United Kingdom: a review.

Science.gov (United States)

Nakagomi, Osamu; Iturriza-Gomara, Miren; Nakagomi, Toyoko; Cunliffe, Nigel A

2013-11-01

Rotavirus, the commonest cause of severe acute gastroenteritis in infants and young children worldwide, imposes a large health and economic burden on the British society, accounting for an estimated 14,300 hospitalisations and 133,000 general practitioner consultations each year among children aged rotavirus vaccine, Rotarix (GlaxoSmithKline Biologicals, Belgium), was introduced into the UK childhood immunisation programme in 2013. This article provides a review of the product profile of the Rotarix vaccine for use in the national immunisation programme in the UK from an expert perspective. This single G1P[8] strain-based human rotavirus vaccine has demonstrated high efficacy in preventing severe rotavirus gastroenteritis in the first 3 years of life in middle- and high-income countries. In countries that have adopted rotavirus vaccine in childhood immunisation programmes, indirect benefits (herd protection) have been observed among older, unvaccinated children and adults. When the first dose is administered between 6 and 14 weeks of age and the last dose by 24 weeks of age, Rotarix carries a small risk of intussusception within the week of vaccination. However, this small risk may at most result in a negligible population attributable risk at the end of the first year of life. Overall, the rotavirus immunisation programme is expected to provide substantial health benefits to the UK population.

MAVS protein is attenuated by rotavirus nonstructural protein 1.

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Satabdi Nandi

Full Text Available Rotavirus is the single, most important agent of infantile gastroenteritis in many animal species, including humans. In developing countries, rotavirus infection attributes approximately 500,000 deaths annually. Like other viruses it establishes an intimate and complex interaction with the host cell to counteract the antiviral responses elicited by the cell. Among various pattern recognition receptors (PAMPs of the host, the cytosolic RNA helicases interact with viral RNA to activate the Mitochondrial Antiviral Signaling protein (MAVS, which regulates cellular interferon response. With an aim to identify the role of different PAMPs in rotavirus infected cell, MAVS was found to degrade in a time dependent and strain independent manner. Rotavirus non-structural protein 1 (NSP1 which is a known IFN antagonist, interacted with MAVS and degraded it in a strain independent manner, resulting in a complete loss of RNA sensing machinery in the infected cell. To best of our knowledge, this is the first report on NSP1 functionality where a signaling protein is targeted unanimously in all strains. In addition NSP1 inhibited the formation of detergent resistant MAVS aggregates, thereby averting the antiviral signaling cascade. The present study highlights the multifunctional role of rotavirus NSP1 and reinforces the fact that the virus orchestrates the cellular antiviral response to its own benefit by various back up strategies.

Epidemiology and genetic diversity of rotavirus strains in children with acute gastroenteritis in Lahore, Pakistan.

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Muhammad Masroor Alam

Full Text Available Pakistan harbors high disease burden of gastro-enteric infections with majority of these caused by rotavirus. Unfortunately, lack of proper surveillance programs and laboratory facilities have resulted in scarcity of available data on rotavirus associated disease burden and epidemiological information in the country. We investigated 1306 stool samples collected over two years (2008-2009 from hospitalized children under 5 years of age for the presence of rotavirus strains and its genotypic diversity in Lahore. The prevalence rate during 2008 and 2009 was found to be 34% (n = 447 out of 1306. No significant difference was found between different age groups positive for rotavirus (p>0.05. A subset of EIA positive samples was further screened for rotavirus RNA through RT-PCR and 44 (49.43% samples, out of total 89 EIA positive samples, were found positive. G and P type prevalence was found as follows: G1P [4] = 3(6.81%; G1P [6] = 9(20.45%; G1P [8] = 1(2.27%; G2P [4] = 21(47.72%; G2P [8] = 1(2.27%; G9P [4] = 1(2.27%; G9P [6] = 1(2.27% and G9P [8] = 7(15.90%. Phylogenetic analysis revealed that the VP7 and VP4 sequences clustered closely with the previously detected strains in the country as well as Belgian rotaviruses. Antigenic characterization was performed by analyzing major epitopes in the immunodominant VP7 and VP4 gene segments. Although the neutralization conferring motifs were found variable between the Pakistani strains and the two recommended vaccines strains (Rotarix™ and RotaTeq™, we validate the use of rotavirus vaccine in Pakistan based on the proven and recognized vaccine efficacy across the globe. Our findings constitute the first report on rotavirus' genotype diversity, their phylogenetic relatedness and epidemiology during the pre-vaccination era in Lahore, Pakistan and support the immediate introduction of rotavirus vaccine in the routine immunization program of the country.

Lightning Tests on the WC-130 Research Aircraft.

Science.gov (United States)

1982-12-01

in the WC-136 tests at various times.) E- Feild Fiber Optic Test Article Sensor Transmitter (Typ)WiePr Indtuced Voltag Sensor"" *Fiber I"=Current optic...well-characterized. 5.1 Skin Current Measurements Skin current vectors were measured at five fuselage locations on the left side of the WC-130 at a...MGL-S7) which were mounted so that they sampled two orthogonal components of the skin current vector . The measured responses were then inte- grated

History of rotavirus research in children in Malawi: the pursuit of a killer

African Journals Online (AJOL)

Rotavirus gastroenteritis is a major health problem among Malawian children. Studies spanning 20 years have described the importance, epidemiology and viral characteristics of rotavirus infections in the country. Despite a wide diversity of circulating rotavirus strains causing severe disease in young infants, a clinical trial ...

Engineering and expression of a human rotavirus candidate vaccine in Nicotiana benthamiana.

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Pêra, Francisco F P G; Mutepfa, David L R; Khan, Ayesha M; Els, Johann H; Mbewana, Sandiswa; van Dijk, Alberdina A A; Rybicki, Edward P; Hitzeroth, Inga I

2015-12-02

Human rotaviruses are the main cause of severe gastroenteritis in children and are responsible for over 500 000 deaths annually. There are two live rotavirus vaccines currently available, one based on human rotavirus serotype G1P[8], and the other a G1-G4 P[8] pentavalent vaccine. However, the recent emergence of the G9 and other novel rotavirus serotypes in Africa and Asia has prompted fears that current vaccines might not be fully effective against these new varieties. We report an effort to develop an affordable candidate rotavirus vaccine against the new emerging G9P[6] (RVA/Human-wt/ZAF/GR10924/1999/G9P[6]) strain. The vaccine is based on virus-like particles which are both highly immunogenic and safe. The vaccine candidate was produced in Nicotiana benthamiana by transient expression, as plants allow rapid production of antigens at lower costs, without the risk of contamination by animal pathogens. Western blot analysis of plant extracts confirmed the successful expression of two rotavirus capsid proteins, VP2 and VP6. These proteins assembled into VLPs resembling native rotavirus particles when analysed by transmission electron microscopy (TEM). Expression of the rotavirus glycoprotein VP7 and the spike protein VP4 was also tried. However, VP7 expression caused plant wilting during the course of the time trial and expression could never be detected for either protein. We therefore created three fusion proteins adding the antigenic part of VP4 (VP8*) to VP6 in an attempt to produce more appropriately immunogenic particles. Fusion protein expression in tobacco plants was detected by western blot using anti-VP6 and anti-VP4 antibodies, but no regular particles were observed by TEM, even when co-expressed with VP2. Our results suggest that the rotavirus proteins produced in N. benthamiana are candidates for a subunit vaccine specifically for the G9P[6] rotavirus strain. This could be more effective in developing countries, thereby possibly providing a higher

Rotavirus - Global research density equalizing mapping and gender analysis.

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Köster, Corinna; Klingelhöfer, Doris; Groneberg, David A; Schwarzer, Mario

2016-01-02

Rotaviruses are the leading reason for dehydration and severe diarrheal disease and in infants and young children worldwide. An increasing number of related publications cause a crucial challenge to determine the relevant scientific output. Therefore, scientometric analyses are helpful to evaluate quantity as well as quality of the worldwide research activities on Rotavirus. Up to now, no in-depth global scientometric analysis relating to Rotavirus publications has been carried out. This study used scientometric tools and the method of density equalizing mapping to visualize the differences of the worldwide research effort referring to Rotavirus. The aim of the study was to compare scientific output geographically and over time by using an in-depth data analysis and New quality and quantity indices in science (NewQIS) tools. Furthermore, a gender analysis was part of the data interpretation. We retrieved all Rotavirus-related articles, which were published on "Rotavirus" during the time period from 1900 to 2013, from the Web of Science by a defined search term. These items were analyzed regarding quantitative and qualitative aspects, and visualized with the help of bibliometric methods and the technique of density equalizing mapping to show the differences of the worldwide research efforts. This work aimed to extend the current NewQIS platform. The 5906 Rotavirus associated articles were published in 138 countries from 1900 to 2013. The USA authored 2037 articles that equaled 34.5% of all published items followed by Japan with 576 articles and the United Kingdom - as the most productive representative of the European countries - with 495 articles. Furthermore, the USA established the most cooperations with other countries and was found to be in the center of an international collaborative network. We performed a gender analysis of authors per country (threshold was set at a publishing output of more than 100 articles by more than 50 authors whose names could be

Cost-effectiveness of rotavirus immunization in Vietnam: Results and challenges

NARCIS (Netherlands)

Tu, H.A.T.; Rozenbaum, M.; Coyte, P.C.; Li, S.C.; Postma, M.J.

2011-01-01

OBJECTIVES: To assess the cost-effectiveness of universal rotavirus immunization, explicitly the use of Rotateq® and affordability of implementing rotavirus immunization based on the Global Alliance for Vaccines and Immunization (GAVI)-subsidized vaccine price in the context of Vietnamese health

New reassortant and enzootic European swine influenza 1 viruses transmits efficiently through direct contact in the ferret model

DEFF Research Database (Denmark)

Fobian, Kristina; P. Fabrizio, Thomas; Yoon, Sun-Woo

2015-01-01

The reverse zoonotic events that introduced the 2009 pandemic influenza virus into pigs have drastically increased the diversity of swine influenza viruses in Europe. The pandemic potential of these novel reassortments is still unclear, necessitating enhanced surveillance of European pigs...... with additional focus on risk assessment of these new viruses. In this study, four European swine influenza viruses were assessed for their zoonotic potential. Two of the four viruses were enzootic viruses of subtype H1N2 (with avian-like H1) and H3N2 and two were new reassortants, one with avian-like H1...... and human-like N2 and one with 2009 pandemic H1 and swine-like N2. All viruses replicated to high titers in nasal wash- and nasal turbinate samples from inoculated ferrets and transmitted efficiently by direct contact. Only the H3N2 virus transmitted to naïve ferrets via the airborne route. Growth kinetics...

The Comparition of the Efficacy of Two Different Probiotics in Rotavirus Gastroenteritis in Children

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Özlem Erdoğan

2012-01-01

Full Text Available Objectives. The aim of the study is to compare the clinical effectiveness of the probiotics—Saccharomyces boulardii and Bifidobacterium lactis—in children who had been diagnosed with rotavirus gastroenteritis. Materials and methods. Seventy five patients aged between 5 months–5 years diagnosed as rotavirus gastroenteritis were included in the study. The patients diagnosed as rotavirus gastroenteritis by latex agglutination test in stool were divided into 3 groups of twenty-five patients each: First group was given oral rehydration therapy and rapid refeeding with a normal diet with Saccharomyces boulardii (spp. I-745, second group was given oral rehydration therapy and rapid refeeding with a normal diet with Bifidobacterium lactis (spp. B94, culture number:∘118529 and third group received only oral rehydration therapy and rapid refeeding with a normal diet. Results. The duration of diarrhea was shorter in the group given oral rehydration therapy and rapid refeeding with a normal diet with Bifidobacterium lactis and Saccharomyces boulardii than the group given only oral rehydration therapy and rapid refeeding with a normal diet. Conclusion. Bifidobacterium lactis has a complemental role in the treatment of rotavirus gatroenteritis and other probiotics may also have a beneficial effect in rotavirus gastroenteritis compared with the therapy included only oral rehydration therapy and rapid refeeding with a normal diet.

Identification of co-infection by rotavirus and parvovirus in dogs with gastroenteritis in Mexico

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Ariadna Flores Ortega

Full Text Available ABSTRACT This is the first report on circulating canine rotavirus in Mexico. Fifty samples from dogs with gastroenteritis were analyzed used polymerase chain reaction and reverse transcription polymerase chain reaction in order to identify parvovirus and rotavirus, respectively; 7% of dogs were infected with rotavirus exclusively, while 14% were co-infected with both rotavirus and parvovirus; clinical signs in co-infected dogs were more severe.

Effect of human rotavirus vaccine on severe diarrhea in African infants.

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Madhi, Shabir A; Cunliffe, Nigel A; Steele, Duncan; Witte, Desirée; Kirsten, Mari; Louw, Cheryl; Ngwira, Bagrey; Victor, John C; Gillard, Paul H; Cheuvart, Brigitte B; Han, Htay H; Neuzil, Kathleen M

2010-01-28

Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine--the pooled vaccine group--or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (Clinical

Anisotropic atomic packing model for abnormal grain growth mechanism of WC-25 wt.% Co alloy

International Nuclear Information System (INIS)

Ryoo, H.S.; Hwang, S.K.

1998-01-01

During liquid phase sintering, cemented carbide particles grow into either faceted or non-faceted grain shapes depending on ally system. In case of WC-Co alloy, prism-shape faceted grains with (0001) planes and {1 bar 100} planes on each face are observed, and furthermore an abnormal grain growth has been reported to occur. When abnormal grain growth occurs in WC crystals, dimension ratio, R, of the length of the side of the triangular prism face to the height of the prism is higher than 4 whereas that for normal grains is approximately 2. Abnormal grain growth in this alloy is accelerated by the fineness of starting powders and by high sintering temperature. To account for the mechanism of the abnormal grain growth, there are two proposed models which drew much research attention: nucleation and subsequent carburization and transformation of η (W 3 Co 3 C) phase into WC, and coalescence of coarse WC grains through dissolution and re-precipitation. Park et al. proposed a two-dimensional nucleation theory to explain the abnormal grain growth of faceted grains. There are questions, however, on the role of η phase on abnormal grain growth. The mechanism of coalescence of spherical grains as proposed by Kingery is also unsuitable for faceted grains. So far theories on abnormal grain growth do not provide a satisfactory explanation on the change of R value during the growth process. In the present work a new mechanism of nucleation and growth of faceted WC grains is proposed on the ground of anisotropic packing sequence of each atom

Genotyping and clinical factors in pediatric diarrhea caused by rotaviruses: one-year surveillance in Surabaya, Indonesia.

Science.gov (United States)

Sudarmo, Subijanto Marto; Shigemura, Katsumi; Athiyyah, Alpha Fardah; Osawa, Kayo; Wardana, Oktavian Prasetia; Darma, Andy; Ranuh, Reza; Raharjo, Dadik; Arakawa, Soichi; Fujisawa, Masato; Shirakawa, Toshiro

2015-01-01

Rotavirus infections are a major cause of diarrhea in children in both developed and developing countries. Rotavirus genetics, patient immunity, and environmental factors are thought to be related to the severity of acute diarrhea due to rotavirus in infants and young children. The objective of this study was to provide a correlation between rotavirus genotypes, clinical factors and degree of severity of acute diarrhea in children under 5 years old in Surabaya, Indonesia. A cross-sectional study was conducted in children aged 1-60 months with acute diarrhea hospitalized in Soetomo Hospital, Surabaya, Indonesia from April to December 2013. Rotavirus in stool specimens was identified by ELISA and genotyping (G-type and P-type) using multiplex reverse transcription PCR. Severity was measured using the Ruuska and Vesikari scoring system. The clinical factors were investigated included patient's age (months), hydration, antibiotic administration, nutritional state, co-bacterial infection and co-viral infection. A total of 88 children met the criteria; 80.7% were aged 6-24 months, watery diarrhea was the most common type (77.3%) and 73.6% of the subjects were co-infected with bacteria, of which pathogenic Escherichia coli was the most common (42.5%). The predominant VP7 genotyping (G-type) was G2 (31.8%) and that of VP4 genotyping (P-type) was P[4] (31.8%). The predominant rotavirus genotype was G2P[4] (19.3%); G1P[4] and G9P[4] were uncommon with a prevalence of 4.5%. There were significant differences between the common genotype and uncommon genotype with respect to the total severity score of diarrhea (p 10 times a day) (p = 0.045) in univariate analyses, but there was no significant correlation between P typing and severity of diarrhea. For combination genotyping of G and P, G2P[4] was significantly correlated with severe diarrhea in multivariate analyses (p = 0.029). There is a correlation between rotavirus genotype and severity of acute diarrhea in

Rotavirus Virus-Like Particles as Surrogates in Environmental Persistence and Inactivation Studies

Science.gov (United States)

Caballero, Santiago; Abad, F. Xavier; Loisy, Fabienne; Le Guyader, Françoise S.; Cohen, Jean; Pintó, Rosa M.; Bosch, Albert

2004-01-01

Virus-like particles (VLPs) with the full-length VP2 and VP6 rotavirus capsid proteins, produced in the baculovirus expression system, have been evaluated as surrogates of human rotavirus in different environmental scenarios. Green fluorescent protein-labeled VLPs (GFP-VLPs) and particles enclosing a heterologous RNA (pseudoviruses), whose stability may be monitored by flow cytometry and antigen capture reverse transcription-PCR, respectively, were used. After 1 month in seawater at 20°C, no significant differences were observed between the behaviors of GFP-VLPs and of infectious rotavirus, whereas pseudovirus particles showed a higher decay rate. In the presence of 1 mg of free chlorine (FC)/liter both tracers persisted longer in freshwater at 20°C than infectious viruses, whereas in the presence of 0.2 mg of FC/liter no differences were observed between tracers and infectious rotavirus at short contact times. However, from 30 min of contact with FC onward, the decay of infectious rotavirus was higher than that of recombinant particles. The predicted Ct value for a 90% reduction of GFP-VLPs or pseudoviruses induces a 99.99% inactivation of infectious rotavirus. Both tracers were more resistant to UV light irradiation than infectious rotavirus in fresh and marine water. The effect of UV exposure was more pronounced on pseudovirus than in GFP-VLPs. In all types of water, the UV dose to induce a 90% reduction of pseudovirus ensures a 99.99% inactivation of infectious rotavirus. Recombinant virus surrogates open new possibilities for the systematic validation of virus removal practices in actual field situations where pathogenic agents cannot be introduced. PMID:15240262

Stellar C III Emissions as a New Classification Parameter for (WC) Central Stars

Science.gov (United States)

Feibelman, W. A.

1999-01-01

We report detection of stellar C III lambda 1909 emission in International Ultraviolet Explorer (IUE) echelle spectra of early-type [WC] planetary nebula central stars (CSPNs). Additionally, stellar C III emission at lambda 2297 is observed in early- and late-type [WC) CSPNS. Inclusion of these C III features for abundance determinations may resolve a conflict of underabundance of C/O for early type [WC2] - [WC4] CSPNS. A linear dependence on stellar C III lambda 2297 equivalent widths can be used to indicate a new classification of type [WCUV] central stars.

A natural M RNA reassortant arising from two distinct tospovirus species

Science.gov (United States)