Rotavirus Genotypes Research Articles

Risk factors for bovine rotavirus infection and genotyping of bovine rotavirus in diarrheic calves in Bangladesh.

Bovine rotavirus (BRV) is considered the leading cause of calf diarrhea worldwide, including Bangladesh. In this study we aimed to identify risk factors for BRV infection and determine the G and P genotypes of BRV strains in diarrheic calves. Fecal samples were collected from 200 diarrheic calves in three districts between January 2014 and October 2015. These samples were screened to detect the presence of BRV using rapid test-strips BIO K 152 (RTSBK). The RTSBK positive samples were further tested by polyacrylamide gel electrophoresis and the silver staining technique to detect rotavirus dsRNA. Risk factors were identified by multivariable logistic regression analysis. The G and P genotypes of BRV were determined by RT-PCR and sequencing. A phylogenetic tree was constructed based on the neighbor-joining method using CLC sequence viewer 8.0. About 23% of the diarrheic calves were BRV positive. The odds of BRV infection were 3.8- (95% confidence interval [95% CI]: 1.0-14.7) and 3.9-times (95% CI:1.1-14.2) higher in Barisal and Madaripur districts, respectively, than Sirrajganj. The risk of BRV infection was 3.1-times (95% CI: 1.5-6.5) higher in calves aged ≤ 5 weeks than those aged >5 weeks. Moreover, the risk of BRV infection was 2.6-times (95% CI:1.1-5.8) higher in crossbred (Holstein Friesian, Shahiwal) than indigenous calves. G6P[11] was the predominant genotype (94.4%), followed by G10P[11] (5.6%). The BRV G6 strains were found to be closest (98.9-99.9%) to Indian strains, and BRV G10 strains showed 99.9% identities with Indian strain. The VP4 gene of all P[11] strains showed >90% identities to each other and also with Indian strains. The most frequently identified BRV genotype was G6P[11]. About 23% of calf diarrhea cases were associated with BRV. To control disease, high-risk areas and younger crossbred calves should be targeted for surveillance and management. The predominant genotype could be utilized as the future vaccine candidate or vaccines with the dominant genotype should be used to control BRV diarrhea in Bangladesh.

Rotavirus genotypes and clinical outcome of natural infection based on vaccination status in the post-vaccine era

ABSTRACT Rotavirus (RV) is a leading cause of gastroenteritis in children. In Japan, Rotarix (RV1; GlaxoSmithKline), which is a monovalent vaccine derived from human RV (G1P[8]), has been introduced since November 2011, and RotaTeq (RV5; MSD) which is an pentavalent, human-bovine mono-reassortant vaccine (G1, G2, G3, G4, and P1A[8]), has been introduced since July 2012. Long-term follow-up on vaccine efficacy and RV genotypical change should be carried out in order to control RV infection. The RV gastroenteritis (RVGE) outbreak occurred during the 2018/2019 season in Aichi prefecture, Japan. Therefore, the molecular epidemiology of RV among three different groups of RVGE, which were outpatients who received RV1, those who received RV5, and those without vaccination, was explored. Clinical features of RVGE patients were compared among the three patient groups. Children less than 15 years of age with gastroenteritis who visited any of seven pediatric practices between January and June 2019 were enrolled in the study. G, P, and E genotypes were determined by direct sequencing of reverse transcription–polymerase chain reaction products amplified from stool samples. Among 110 patients, there were 27, 28, and 55 in the RV1-vaccinated, RV5-vaccinated, and unvaccinated groups, respectively. The most frequent genotype was G8P[8] (92/110 patients, 83.6%). Genotype distributions did not significantly differ among the three patient groups (P = .125). Mean Vesikari score was significantly lower among RV1-vaccinated (7.1) and RV5-vaccinated patients (6.4) than among unvaccinated patients (10.2) (P < .001). Even in RVGE patients treated in an outpatient clinic, RV vaccine reduced the severity of the disease in this cohort.

Molecular Epidemiology of Rotavirus Strains in Symptomatic and Asymptomatic Children in Manhiça District, Southern Mozambique 2008-2019.

Group A rotaviruses remain the leading cause of diarrhoea in children aged <5 years. Mozambique introduced rotavirus vaccine (Rotarix®) in September 2015. We report rotavirus genotypes circulating among symptomatic and asymptomatic children in Manhiça District, Mozambique, pre- and post-vaccine introduction. Stool was collected from enrolled children and screened for rotavirus by enzyme-immuno-sorbent assay. Positive specimens were genotyped for VP7 (G genotypes) and VP4 (P genotypes) by the conventional reverse transcriptase polymerase chain reaction. The combination G12P[8] was more frequently observed in pre-vaccine than in post-vaccine introduction, in moderate to severe diarrhoea (34%, 61/177 vs. 0, p < 0.0001) and controls (23%, 26/113 vs. 0, p = 0.0013) and mixed genotypes (36%, 24/67 vs. 7% 4/58, p = 0.0003) in less severe diarrhoea. We observed changes in post-vaccine compared to pre-vaccine introduction, where G3P[4] and G3P[8] were prevalent in moderate to severe diarrhoea (10%, 5/49 vs. 0, p = 0.0002; and 14%, 7/49 vs. 1%, 1/177, p < 0.0001; respectively), and in less severe diarrhoea (21%, 12/58 vs. 0, p = 0.003; and 24%, 14/58 vs. 0, p < 0.0001; respectively). Our surveillance demonstrated the circulation of similar genotypes contemporaneously among cases and controls, as well as switching from pre- to post-vaccine introduction. Continuous surveillance is needed to evaluate the dynamics of the changes in genotypes following vaccine introduction.

Genotype Profiles of Rotavirus Strains in Children under 5-year-old Outpatients with Diarrhea in Bandung, West Java, Indonesia.

Diarrhea is a global leading cause of morbidity and mortality among children under five, with rotaviruses being the most common cause. This study aimed to determine the genotypes of rotavirus in children under 5 years with diarrhea in Bandung, Indonesia. This cross-sectional study was conducted from 2014 to 2018 on 450 children under five with acute diarrhea in primary health centers in Bandung, Indonesia. Fecal samples were examined for rotavirus antigen using an enzyme-linked immunosorbent assay method, and genotype was determined through sequencing using polymerase chain reaction. Results were statistically analyzed using Pearson Chi-square in Epi Info version 3.5.4, with P < 0.05 considered statistically significant. Rotavirus was identified in 8.9% of the subjects, slightly higher in boys (n = 24, 9.8%) than girls (n = 16, 7.8%). We found that the most rotavirus positive in age group is >12-24 months and >24-59 months, while the highest percentage is at the age of ≤6 months (11.8%). Moderate malnutrition was observed in more subjects (12.8%). Vomiting was more frequent in patients positive (55%, P = 0.013) and fever was seen in 32.5% (P = 0.645). No signs of dehydration were seen in most subjects (75%), P = 0.227. Rotavirus genotypes identified were G1P[8] (18, 45%), G3P[8] (14, 35%), G3P[6] (4, 10%), G3P[9] (2, 5%), G2P[4] (1, 2.5%), and nontypeable (NT) (1, 2.5%). The dominant rotavirus genotype is G1P[8], followed by G3P[8], G3P[6], G3P[9], G2P[4], and NT. The most common rotavirus positive in age group is >12-24 months and >24-59 months, while the highest percentage is at the age of ≤6 months.

The Role of Host Glycobiology and Gut Microbiota in Rotavirus and Norovirus Infection, an Update.

Rotavirus (RV) and norovirus (NoV) are the leading causes of acute gastroenteritis (AGE) worldwide. Several studies have demonstrated that histo-blood group antigens (HBGAs) have a role in NoV and RV infections since their presence on the gut epithelial surfaces is essential for the susceptibility to many NoV and RV genotypes. Polymorphisms in genes that code for enzymes required for HBGAs synthesis lead to secretor or non-secretor and Lewis positive or Lewis negative individuals. While secretor individuals appear to be more susceptible to RV infections, regarding NoVs infections, there are too many discrepancies that prevent the ability to draw conclusions. A second factor that influences enteric viral infections is the gut microbiota of the host. In vitro and animal studies have determined that the gut microbiota limits, but in some cases enhances enteric viral infection. The ways that microbiota can enhance NoV or RV infection include virion stabilization and promotion of virus attachment to host cells, whereas experiments with microbiota-depleted and germ-free animals point to immunoregulation as the mechanism by which the microbiota restrict infection. Human trials with live, attenuated RV vaccines and analysis of the microbiota in responder and non-responder individuals also allowed the identification of bacterial taxa linked to vaccine efficacy. As more information is gained on the complex relationships that are established between the host (glycobiology and immune system), the gut microbiota and intestinal viruses, new avenues will open for the development of novel anti-NoV and anti-RV therapies.

Reduction in Severity of All-Cause Gastroenteritis Requiring Hospitalisation in Children Vaccinated against Rotavirus in Malawi.

Rotavirus is the major cause of severe gastroenteritis in children aged <5 years. Introduction of the G1P[8] Rotarix® rotavirus vaccine in Malawi in 2012 has reduced rotavirus-associated hospitalisations and diarrhoeal mortality. However, the impact of rotavirus vaccine on the severity of gastroenteritis presented in children requiring hospitalisation remains unknown. We conducted a hospital-based surveillance study to assess the impact of Rotarix® vaccination on the severity of gastroenteritis presented by Malawian children. Stool samples were collected from children aged <5 years who required hospitalisation with acute gastroenteritis from December 2011 to October 2019. Gastroenteritis severity was determined using Ruuska and Vesikari scores. Rotavirus was detected using enzyme immunoassay. Rotavirus genotypes were determined using nested RT-PCR. Associations between Rotarix® vaccination and gastroenteritis severity were investigated using adjusted linear regression. In total, 3159 children were enrolled. After adjusting for mid-upper arm circumference (MUAC), age, gender and receipt of other vaccines, all-cause gastroenteritis severity scores were 2.21 units lower (p < 0.001) among Rotarix®-vaccinated (n = 2224) compared to Rotarix®-unvaccinated children (n = 935). The reduction in severity score was observed against every rotavirus genotype, although the magnitude was smaller among those infected with G12P[6] compared to the remaining genotypes (p = 0.011). Each one-year increment in age was associated with a decrease of 0.43 severity score (p < 0.001). Our findings provide additional evidence on the impact of Rotarix® in Malawi, lending further support to Malawi’s Rotarix® programme.

Study the Distribution of Rotavirus Genotypes in Vaccinated and non Vaccinated Children in Babylon Province

Rotaviruses, a major cause of gastroenteritis in children worldwide accounts for around half a million deaths annually. Vaccine against the virus has been recommended by the WHO to be involved in the national immunization program.To evaluate the genetic characterization of rotavirus among children with acute gastroenteritis in Babylon province is warranted. Children complained of diarrhea with rotavirus infection detected in their stool were involved in the study. The age range was 10 months to 60 months and with retrogradechecking of rotavirus vaccine history. Rotavirus genotypes were detected by reverse transcription-polymerase chain reaction (RT-PCR).A total number of 40 children with rotavirus gastroenteritis were used to examine the rotavirus genotyping distribution. The prevalent genotypes were found to be G1, G9, and G2. No significant difference in the distribution of the length of diarrhea according to genotype. Vaccinated children exhibited significantly higher percentage of G2 while G1 and G9 were presented more considerably in not vaccinated children.We detected a variety of rotavirus strains includingthe major global genotypes.Obviously, rotavirus strains are continuing to vary in Iraq. The vaccination changes the genotype prevalence and this situation may create challenges to the effectiveness of rotavirus vaccines and planning for future polices.&#x0D; &#x0D; Keywords: Rotavirus, Vaccine, Genotype.

Genetic diversity of rotavirus strains circulating in Norway before and after the introduction of rotavirus vaccination in children.

Globally, rotavirus (RV) is the leading cause of acute gastroenteritis (AGE) in young children under 5 years of age. Implementation of RV vaccination is expected to result in fewer cases of RV in the target population, but it is unknown if this also results in vaccine-induced virus strain replacement. Rotarix, a monovalent vaccine based on G1P[8] RV, was introduced in Norway in the children's immunization program in September 2014. The main aim of this study was to describe the diversity of RV circulating pre and post introduction of the RV vaccine in Norway and investigate changes in genotype distribution during the first 4 years after implementation. A total of 1108 samples were collected from children under 5 years enrolled with AGE from five large hospitals in Norway and were analyzed for RV by enzyme immunoassay (EIA). All positive results were genotyped by multiplex semi-nested reverse transcription PCR for identification of G and P types. In total, 487 of the 1108 (44%) samples, collected from the enrolled children, were positive for RV by EIA method which were further genotyped. G1P[8] was found to be the most common type of RV pre and post RV vaccine implementation followed by G9P[8]. There were neither geographical nor temporal differences in genotype dominance. Also, no apparent changes were shown in the genotype distribution in the postvaccine era for years from 2015 to 2018. In 21.4% of the cases, vaccine strains were detected. Continuous RV genotype surveillance is vital for assessing the effectiveness of a vaccine program and monitoring for any emergence of vaccine-escape strains. Genotyping is also necessary to detect vaccine strains to avoid reporting false-positive cases of active RV infection in newly vaccinated cases.

Plasma Rotavirus-specific IgA and Risk of Rotavirus Vaccine Failure in Infants in Malawi.

BackgroundRotavirus vaccine efficacy is reduced in low-income populations, but efforts to improve vaccine performance are limited by lack of clear correlates of protection. While plasma rotavirus (RV)-specific IgA appears strongly associated with protection against rotavirus gastroenteritis in high-income countries, weaker association has been observed in low-income countries. We tested the hypothesis that lower RV-specific IgA is associated with rotavirus vaccine failure in Malawian infants.MethodsIn a case-control study we recruited infants presenting with severe rotavirus gastroenteritis following monovalent oral rotavirus vaccination (RV1 vaccine failures). Conditional logistic regression was used to determine the odds of rotavirus seronegativity (RV-specific IgA<20 U/mL) in these cases compared 1:1 with age-matched, vaccinated, asymptomatic community controls. Plasma RV-specific IgA was determined by ELISA for all participants at recruitment, and for cases at 10 days post symptom onset. Rotavirus infection and genotype were determined by antigen testing and RT-PCR respectively.ResultsIn 116 age-matched pairs, infants with RV1 vaccine failure were more likely to be RV-specific IgA seronegative than controls: OR 3.1 (95%CI 1.6-5.9), p=0.001. In 60 infants with convalescent serology, 42/45 (93%, 95%CI 81-98%) infants seronegative at baseline became seropositive. Median rise in RV-specific IgA concentration following acute infection was 112.8 (IQR 19.1-380.6) fold.ConclusionsIn this vaccinated population with high residual burden of rotavirus disease, RV1 vaccine failure was associated with lower RV-specific IgA, providing further evidence of RV-specific IgA as a marker of protection. Robust convalescent RV-specific IgA response in vaccine failures suggests differences in wild-type and vaccine-induced immunity, which informs future vaccine development.

A major decrease in viral acute gastroenteritis in hospitalized Finnish children as rotavirus returns as the most detected pathogen

IntroductionThis study was performed to assess the prevalence and circulating genotypes of rotavirus, norovirus, and sapovirus in children. The results were compared to those of previous surveillance studies covering the years 2006–2008, 2009–2011, and 2012–2014 with similar methodology and setting, encompassing the start of universal vaccination with RotaTeq in 2009. MethodsStool samples were collected from children aged <16 years with acute gastroenteritis at Tampere University Hospital, Finland, from January 1, 2017 to December 31, 2018. The samples were analysed using reverse transcription PCR and positive amplicons were sequenced. ResultsA total of 178 stool samples were collected from 214 children. Rotavirus was detected in 56 (32%) stool samples, norovirus in 48 (27%), and sapovirus in 11 (6.3%). Rotavirus G9P[8] and G12P[8] were the most detected genotypes in vaccinated and unvaccinated children. GII.4 comprised 96% of the norovirus detections. ConclusionsThe prevalence of all-cause acute gastroenteritis in a hospital setting decreased by 51% compared to 2012–2014, and by 88% compared to 2006–2008 . Rotavirus returned as the most common cause of viral acute gastroenteritis in children, but the prevalence remains at a low level. No considerable changes were seen in the genotyping results of norovirus and sapovirus.

Rotavirus Genotypes in Abuja, Nigeria

Introduction: Nigeria had planned to introduce the rotavirus vaccine in the National Immunisation Programme in 2014, but this has yet to be done. Nigeria has the continent's highest mortality due to diarrhoeal diseases with little information on specific, prevalent genotypes.&#x0D; Aim: The study's main objectives were to identify the predominant rotavirus genotypes and examine the effects of existing local vaccination programs on prevailing rotavirus genotypes and on preventing rotavirus diarrhoea.&#x0D; Methodology: A one-year prospective descriptive study of children under 5 with acute diarrhoea was conducted from June 2018 to May 2019. Children with acute diarrhoea attending Asokoro District Hospital, Abuja. Children without diarrhoea were also recruited as a control group. Rotavirus ELISA and RNA extraction were done with commercially available kits, and positive samples were subjected to RT-PCR and electrophoresis to determine VP7 (G) and VP4 (P) genotypes.&#x0D; Results: Rotavirus-ELISA was positive among 231 (17.8%) children with diarrhoea and 29 (2.2%) of controls, with November, December. The predominant VP7 genotypes was G1 (n=116, 50.2%) followed by G9 (n=66, 28.5%). Viral Protein, VP4 (P) was mostly P [8] (n=143, 74.8%) followed by P [4] (n=21, 10.9%). The predominant genotype combinations found were G1 P [8] (n=108, 46.7%), G9 P [8] (n=62, 26.8%), and G2 P [4] (n=18, 7.7%). Very few mixed infections were found in the study, 2 (0.8%). Among 94 unvaccinated children with rotavirus isolates that were genotyped, G1 P [8] (n=88, 49.4%) and G9 P [8] (n=43, 24.1%) were predominant. Among 32 vaccinated children, G1 P [8] (n=13, 40.2%) and G9 P [8] (n=9, 28.1%) were predominant.&#x0D; Conclusion: The emergence of new genotypes such as G 12 P [4] found in this study emphasize the need for continued prospective monitoring of rotavirus at the molecular level to detect new threats to vaccine programs in future.

The Emergence of New Rotavirus Strains in America

Rotavirus infections are the most common causes of infectious diarrhea in young children and animal worldwide. In some countries in Latin American specifically in Central American and Caribbean countries, rotavirus infections are not subject to specific surveillance. This review is about the unusually strains detected and potential zoonotic of rotavirus in Latin American. Although, interspecies transmission has not been documented to occur directly, an increase of the number of reports of atypical rotavirus genotypes; apparently derived from transmission between animal of farm, domestic and wild with humans, has been reported in some Latin American countries and the world. We consider that the rapid increase in the detection of new unusual strains with genetic heterogeneity, raises interesting questions about the evolution of rotavirus in The Latin American region. The emergence of novel strains derived from interspecies transmission has implications for the design and implementation of successful human rotavirus vaccine strategies.

Investigation of Group A Rotavirus G10, G12 Genotypes Emerging in Patients with Acute Gastroenteritis in a Tertiary Care Hospital

Rotaviruses are the most common cause of viral gastroenteritis with the highest mortality and morbidity rates in children aged 0-5 years. The aim of this study was to determine the frequency of rotavirus infection in patients whose stool samples were sent to microbiology laboratory to investigate the etiology of diarrhea, to investigate the rotavirus genotypes that are common in our region and G10, G12 genotypes that have recently become common in the world. Fecal samples of 476 patients aged between 0-92 years who applied between November 2016 and February 2018 were studied via immunochromatographic rapid test and enzyme-linked immunosorbent assay (ELISA) methods. ELISA positive samples were studied by nested reverse transcriptase chain reaction (RT-PCR) and genotyped by agarose gel electrophoresis. Rotavirus was found positive in 18.3% and 17% of stool samples by immunochromatographic test and ELISA, respectively. All ELISA positive samples were also detected as positive by RT-PCR. 18.5% of female patients and 15.7% of male patients were found to be positive and rotavirus positivity was not statistically significant between genders. The frequency of rotavirus in different age groups was 23.5% (6-12 years), 17.3% (13-24 months) and 16% (25-36 months). It was determined that rotavirus cases were most common in the spring. G1, G2, G3, G4, G9, G10, and G12 were detected in 37%, 7.4%, 16.1%, 6.2%, 9.9%, 2.5%, 26% of the samples, respectively. G12 was the most common genotype after G1. The most common G and P genotype combination was G1P[8] (17.2%). This was followed by G12P[8] (11.11%) and G3P[8] (11.11%). P[8] (53%) was found to be the dominant P genotype. In this study, it was observed that rotavirus, which is the cause of childhood diarrhea, can also be encountered in advanced ages and even new genotypes that infect humans worldwide may also be the causative agents. Therefore, we concluded that it is important to investigate new genotypes such as G10 and G12 in molecular epidemiological studies.

Genetic characteristics of group A rotaviruses circulating in the Orenburg region during various epidemic seasons

Objective. To analyze the genetic structure of rotaviruses of group A, circulating on the territory of the Orenburg region in different epidemic seasons.Materials and methods: The genetic structure of rotaviruses by G/P alleles was determined in 341 fecal samples of patients with gastroenteritis clinic under the age of 5 years in various epidemic seasons. ELISA and PCR methods were used. The typing of rotaviruses was conducted on the basis of the laboratory of molecular diagnostic and epidemiology of enteric infections of the Department molecular diagnostics Central research Institute of epidemiology.Results: The general genetic structure of group a rotaviruses circulating in the Orenburg region in the period from 2014—2020 was determined, expressed, by the frequencies of G/P alleles. The genetic potential of group a rotaviruses for the entire study period was represented by twelve variants of genotypes for G/P alleles, the leading role in the epidemic process was played by genotypes with the highest frequency of occurrence: G4[P]8, G9[P]8, G2[P]4, Mixt. The frequency of registration of combined forms of various rotavirus genotypes (Mixed forms) was 5,9%.Conclusion: The main and dominant genotypes, their regional diversity and inter-seasonal fluctuations are established. The spectrum of circulating rotavirus genotypes differed in different epidemic seasons, and their epidemic significance is shown.

Investigation of the Rotavirus Genotypes Isolated From Patients With Acute Gastroenteritis and the Increase of G9 Type

Investigation of the Rotavirus Genotypes Isolated From Patients With Acute Gastroenteritis and the Increase of G9 Type

Emergence of equine-like G3 strains as the dominant rotavirus among children under five with diarrhea in Sabah, Malaysia during 2018-2019.

Rotavirus infection is a dilemma for developing countries, including Malaysia. Although commercial rotavirus vaccines are available, these are not included in Malaysia’s national immunization program. A scarcity of data about rotavirus genotype distribution could be partially to blame for this policy decision, because there are no data for rotavirus genotype distribution in Malaysia over the past 20 years. From January 2018 to March 2019, we conducted a study to elucidate the rotavirus burden and genotype distribution in the Kota Kinabalu and Kunak districts of the state of Sabah. Stool specimens were collected from children under 5 years of age, and rotavirus antigen in these samples was detected using commercially available kit. Electropherotypes were determined by polyacrylamide gel electrophoresis of genomic RNA. G and P genotypes were determined by RT-PCR using type specific primers. The nucleotide sequence of the amplicons was determined by Sanger sequencing and phylogenetic analysis was performed by neighbor-joining method. Rotavirus was identified in 43 (15.1%) children with watery diarrhea. The male:female ratio (1.9:1) of the rotavirus-infected children clearly showed that it affected predominantly boys, and children 12–23 months of age. The genotypes identified were G3P[8] (74% n = 31), followed by G1P[8] (14% n = 6), G12P[6](7% n = 3), G8P[8](3% n = 1), and GxP[8] (3% n = 1). The predominant rotavirus circulating among the children was the equine-like G3P[8] (59.5% n = 25) with a short electropherotype. Eleven electropherotypes were identified among 34 strains, indicating substantial diversity among the circulating strains. The circulating genotypes were also phylogenetically diverse and related to strains from several different countries. The antigenic epitopes present on VP7 and VP4 of Sabahan G3 and equine-like G3 differed considerably from that of the RotaTeq vaccine strain. Our results also indicate that considerable genetic exchange is occurring in Sabahan strains. Sabah is home to a number of different ethnic groups, some of which culturally are in close contact with animals, which might contribute to the evolution of diverse rotavirus strains. Sabah is also a popular tourist destination, and a large number of tourists from different countries possibly contributes to the diversity of circulating rotavirus genotypes. Considering all these factors which are contributing rotavirus genotype diversity, continuous surveillance of rotavirus strains is of utmost importance to monitor the pre- and post-vaccination efficacy of rotavirus vaccines in Sabah.

Circulating Rotavirus Genotypes among Children Younger than 5 Years with Acute Gastroenteritis in Zaria, Northwestern Nigeria

Abstract Objective This study aimed to determine the circulating rotavirus genotypes among children 0 to 59 months with acute gastroenteritis in Zaria, Northwestern Nigeria. Methods A cross-sectional hospital-based study was performed from November 2015 to April 2017 on 415 stool samples of children 0 to 59 months with acute gastroenteritis presenting at the pediatric clinics in five selected health care facilities in Zaria, Northwestern Nigeria. The stool samples were tested for group A rotavirus antigen by enzyme-linked immunosorbent assay (ELISA) using the ProSpecT™ Rotavirus Microplate Assay (Thermo Scientific Oxoid, United Kingdom). Rotavirus-positive strains were further characterized using seminested multiplex reverse transcriptase polymerase chain reaction. Results Of the 415 diarrheal stool samples collected from children with acute gastroenteritis, 12.3% (n = 51) tested positive by ELISA. Five rotavirus G genotypes (G1, G2, G3, G9, and G12) and three P genotypes (P[4], P[6], and P[8]) were detected. Eight genotype combinations were detected with G1P[8], G12P[8], and G3P[6] being the most prevalent (9.8% each) followed by G1P[6], G2P[4], and G9P[8] (5.9% each). G/P mix types representing 25.5% (n = 13) of strains were detected during the study period. Conclusion This study found a high diversity of rotavirus strains with emerging unusual rotavirus genotypes and a concurrent high proportion of mixed infections. This increased antigenic diversity of rotavirus strains may impact on vaccine effectiveness and rotavirus epidemiology and highlights the importance of continuous surveillance.

Structural Basis of Glycan Recognition of Rotavirus

Rotavirus (RV) is an important pathogen causing acute gastroenteritis in young humans and animals. Attachment to the host receptor is a crucial step for the virus infection. The recent advances in illustrating the interactions between RV and glycans promoted our understanding of the host range and epidemiology of RVs. VP8*, the distal region of the RV outer capsid spike protein VP4, played a critical role in the glycan recognition. Group A RVs were classified into different P genotypes based on the VP4 sequences and recognized glycans in a P genotype-dependent manner. Glycans including sialic acid, gangliosides, histo-blood group antigens (HBGAs), and mucin cores have been reported to interact with RV VP8*s. The glycan binding specificities of VP8*s of different RV genotypes have been studied. Here, we mainly discussed the structural basis for the interactions between RV VP8*s and glycans, which provided molecular insights into the receptor recognition and host tropism, offering new clues to the design of RV vaccine and anti-viral agents.

Rotavirus vaccine efficacy up to 2 years of age and against diverse circulating rotavirus strains in Niger: Extended follow-up of a randomized controlled trial.

BackgroundRotavirus vaccination is recommended in all countries to reduce the burden of diarrhea-related morbidity and mortality in children. In resource-limited settings, rotavirus vaccination in the national immunization program has important cost implications, and evidence for protection beyond the first year of life and against the evolving variety of rotavirus strains is important. We assessed the extended and strain-specific vaccine efficacy of a heat-stable, affordable oral rotavirus vaccine (Rotasiil, Serum Institute of India, Pune, India) against severe rotavirus gastroenteritis (SRVGE) among healthy infants in Niger.Methods and findingsFrom August 2014 to November 2015, infants were randomized in a 1:1 ratio to receive 3 doses of Rotasiil or placebo at approximately 6, 10, and 14 weeks of age. Episodes of gastroenteritis were assessed through active and passive surveillance and graded using the Vesikari score. The primary endpoint was vaccine efficacy of 3 doses of vaccine versus placebo against a first episode of laboratory-confirmed SRVGE (Vesikari score ≥ 11) from 28 days after dose 3, as previously reported. At the time of the primary analysis, median age was 9.8 months. In the present paper, analyses of extended efficacy were undertaken for 3 periods (28 days after dose 3 to 1 year of age, 1 to 2 years of age, and the combined period 28 days after dose 3 to 2 years of age) and by individual rotavirus G type. Among the 3,508 infants included in the per-protocol efficacy analysis (mean age at first dose 6.5 weeks; 49% male), the vaccine provided significant protection against SRVGE through the first year of life (3.96 and 9.98 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 60.3%, 95% CI 43.6% to 72.1%) and over the entire efficacy follow-up period up to 2 years of age (2.13 and 4.69 cases per 100 person-years for vaccine and placebo, respectively; vaccine efficacy 54.7%, 95% CI 38.1% to 66.8%), but the difference was not statistically significant in the second year of life. Up to 2 years of age, rotavirus vaccination prevented 2.56 episodes of SRVGE per 100 child-years. Estimates of efficacy against SRVGE by individual rotavirus genotype were consistent with the overall protective efficacy. Study limitations include limited generalizability to settings with administration of oral polio virus due to low concomitant administration, limited power to assess vaccine efficacy in the second year of life owing to a low number of events among older children, potential bias due to censoring of placebo children at the time of study vaccine receipt, and suboptimal adapted severity scoring based on the Vesikari score, which was designed for use in settings with high parental literacy.ConclusionsRotasiil provided protection against SRVGE in infants through an extended follow-up period of approximately 2 years. Protection was significant in the first year of life, when the disease burden and risk of death are highest, and against a changing pattern of rotavirus strains during the 2-year efficacy period. Rotavirus vaccines that are safe, effective, and protective against multiple strains represent the best hope for preventing the severe consequences of rotavirus infection, especially in resource-limited settings, where access to care may be limited. Studies such as this provide valuable information for the planning of national immunization programs and future vaccine development.Trial registrationClinicalTrials.gov NCT02145000.

Immunological and molecular detection of rotavirus genotype in calves with gastroenteritis in Diyala-Iraq

Aim: To explore the prevalence of rotavirus infection along with the molecular detection and genotyping of group A rotavirus (RVA) among bovine calves up to 5 months old in Diyala province-Iraq. Methods: This is a cross sectional study conducted in Diyala province-Iraq during the period of 2019-2020. One hundred bovine calves with age range of 1-5 months were included in the study. All were suffering acute gastroenteritis. Serum anti-rotavirus IgM and IgG plus fecal rotavirus Ag were tested for using ELISA techniques. Stool samples positive for rotavirus Ag were submitted for reverse transcription PCR (RT-PCR) for G and P genes, followed by sequencing and genotyping thereafter. Statistical analysis was done using SPSS version 25 and P values ≤ 0.05 were considered significant. Results: The positivity rate of anti-rotavirus IgM was 80% (P = 0.0001), and that of anti-rotavirus IgG was 79% (P = 0.0001). The rotavirus stool antigen was detected in 68% of calves (P = 0.01). A total of 45 stool samples which were positive for rotavirus Ag were submitted for RT-PCR; 13 (28.9%) were positive and 32 (71.1%) were negative (P = 0.084). 10 PCR positive samples were used for sequencing and genotyping and indicated that all investigated strains belonged to G1P[8] genotype. Conclusion: The current strains analyzed belonged to the G1P[8] RVA genotypes, affirming that employment of VP7 gene polymorphism accurately yielded uniform phylogenetic distances amongst investigated rotavirus strains and that there were no noticeable assortment events between human and animal rotavirus strains in Diyala province.