Detection of human rotavirus in hospitalized diarrheic children in central India

During the present study, group A human rotaviruses were detected among diarrheic children using polyacrylamide gel electrophoresis (PAGE) technique, with a typical RNA migration pattern of 4:2:3:2, suggestive of group A rotavirus. During the study, a total of 46 fecal samples collected from hospitalized children with acute diarrhea as well as children inhabiting nearby animal farms with history of presence of animal rotaviruses on the farms were processed for detection of human rotavirus. Out of 33 diarrheic children, 12 showed presence of rotavirus infection (36.36%), however, none of the children from animal farm areas showed presence of rotavirus. Female children were more susceptible to rotavirus infection (46.15%) than males (30%). Majority of the cases of rotavirus gastroenteritis belonged up to one year of the age, with an incidence of 40.91%. RNA profile of rotaviruses suggested circulation of 5 different electropherotypes in this geographical locale of the country, indicating existence of genomic diversity among human rotaviruses. Majority of the isolates were of long pattern (66.67%), whereas short pattern was detected only in one third of the viruses. This preliminary study emphasizes for further detailed studies on the molecular characterization of rotaviruses circulating in this part of country and their relationship with other human rotavirus strains and animal strains in the country.     

Genomic diversity among group A rotaviruses from diarrheic children,piglets, buffalo and cow calves of Madhya Pradesh

Diarrheal disease continues to be a global health problem, particularly among young ones in developing nations. Amongst several viral and non-viral agents associated with diarrhea, group A rotavirus has been recognized as the major etiological agent of childhood gastroenteritis in human infants as well as several animal species throughout the world. During this study, a total of 181 diarrheic stool samples collected from children, piglets, buffalo and cow calves of Madhya Pradesh, central India were analyzed by electrophoretic mobilities of the 11 segments of dsRNA by polyacrylamide gel electrophoresis (PAGE). This technique revealed prevalence of rotavirus among different species (human-26.09%, pig-25.71%, buffalo-23.61% and cattle-21.43%). Prevalence of existence of circulating 8 different electropherotypes of group A rotaviruses indicated high genomic diversity among rotaviruses in this geographical region. Majority of the electropherotypes from humans and animals were of long pattern (75%) than short electropherotypes (9.09%). Same electropherotype was found to exist either only in a single species or in more than one species implicating the possibility of cross species transmission of the rotavirus strains. As it was found that certain animal rotavirus strains had electropherotypic similarities to some human strains, speculation increased about whether animals play a role as a source of rotavirus infection in humans or vice-versa. There is a need for further detailed study on the molecular characterization of rotaviruses which would have important implication in vaccine evaluation program.     

Comparison of the genomes of simian, bovine, and human rotaviruses by gel electrophoresis and detection of genomic variation among bovine isolates.

By co-electrophoresis in polyacrylamide gels, the segmented double-standed RNA genome of the simian rotavirus, SA 11, was compared with those of human and bovine rotaviruses. A comparison between SA 11 virus and the Northern Ireland cell culture adapted bovine virus showed that the electrophoretic mobilities of each of the 11 corresponding segments differed. In other comparisons, four to seven segment variations were more common. When the genomes of various bovine rotaviruses were compared, eight different electropherotypes were detected. Four of these electropherotypes were obtained from one property during a single outbreak of disease. In view of such genetic diversity, a scheme for the systematic designation of different rotavirus samples is proposed. The significance of the variations in relation to the molecular epidemiology of bovine rotavirus infections is discussed.     

Microbiological and epidemiological aspects of rotavirus and enteric adenovirus infections in hospitalized children in Italy

Rotaviruses and enteric adenoviruses are the most important causative agents of acute infantile gastroenteritis worldwide. From July 2005 to June 2007, 445 stool specimens from pediatric patients hospitalized with acute diarrhea were collected and tested for the presence of rotaviruses and enteric adenoviruses using an immunochromatographic assay. Rotavirus infection was detected in 123 cases (27.6%, ranging from 31.7% in 2005-2006 to 24.2% in 2006-2007); adenovirus infection occurred in 17 cases (3.8%, 13 cases in 2005-2006 (6.3%) and 4 cases in 2006-2007 (1.7%). The highest prevalence was seen in children from 13 to 24 months for rotaviruses, and in children from 25 to 36 months for adenoviruses. Rotavirus infection was detected with significantly higher frequency in children up to 36 months old (32.0%) compared to the older children (19.9%) (P < 0.01). Mixed infections were observed in 10 cases (6 rotavirus-adenovirus, and 4 rotavirus-Salmonella spp.). Rotavirus infection was found predominantly in winter and spring with respect to autumn (P < 0.001) or summer (P < 0.05), with a peak in February. Adenovirus infection had a major epidemic period in spring 2006, peaking in March. Finally, this study indicates that many patients acquired rotavirus infection (37.4%), and enteric adenovirus infection (41.2%) during hospitalization for other underlying diseases.     

Detection and characterization of rotavirus G and P types from children participating in a rotavirus vaccine trial in Belém, Brazil

This study sought the characterization of rotaviruses in a trial with a tetravalent rhesus-human rotavirus vaccine in Belém, Brazil in children who received three doses of vaccine or placebo in the 1st, 3rd and 5th months of life. Rotavirus electropherotypes, subgroups, G serotypes, G, [P] and [P], G genotypes were determined in 93.3%, 95.9%, 93.3%, 73.3%, 95.5% and 92.2% of isolates, respectively. Serotypes G1, G2 and G4 were detected in 58.9%, 30% and 4.4% of the cases, respectively. Rotavirus genotype G5 was detected for the first time in Northern region in 4.4% of the infections. Rotavirus genotypes P[8], P[4], P[6] and P[8 + 6] were detected in 54.5%, 26.7%, 12.2%, and 2.2% of the cases, respectively. The predominant genotypes were P[8], G1 and P[4], G2 with 53% and 26.6% of the infections, respectively. Unusual strains accounted for 20.5% including P[4], G1, P[6], G1, P[6], G4, P[6], G5, P[8], G2, P[8], G5. Mixed infections involving P[8 + 6], G2 and P[8 + 6], G1 were also noted. The neonatal P[6] strains associated with diarrhea were detected among children aged 9-24 months. To our knowledge, this study represents the first in Brazil to analyse, on molecular basis, rotavirus genotypes from children participating in a rotavirus vaccine trial. These results are of potential importance regarding future rotavirus vaccination strategies in Brazil.     

Atypical rotavirus among diarrhoeic children living in Belém, Brazil

Atypical rotaviruses were detected in faeces from two diarrhoeic children living in Belém, Pará, Brazil. Rotavirus particles were detected by electron microscopy and the RNA electrophoresis showed patterns which were compatible with group C rotaviruses. Tests for the presence of group A antigen by enzyme-linked-immunosorbent assay (ELISA) were negative. The two children had three successive rotavirus infections and in both cases the atypical strains were excreted at the time of the third infection, causing a mild and short-lasting disease.     

Detection of Rotavirus from Hospitalized Diarrheic Children in Uttar Pradesh, India

In the present study 220 stool samples collected from diarrheic children admitted to different hospitals and nursing homes of Uttar Pradesh and Uttarakhand were screened for rotavirus. Of 220 diarrheic samples screened 46 samples were found to be positive for rotavirus by RNA PAGE. All the isolates exhibited 4-2-3-2 migration pattern suggesting group A rotavirus. Both long and short electropherotypes were prevalent in these regions. Six different electropherotypes were detected in this study period. Male diarrheic children were found to be more susceptible to rotavirus infection (22.96 %) than that of the female ones (17.64 %). Viral RNA isolated from stool samples again subjected to VP4 gene amplification by RT-PCR using con2 and con3 primer which resulted 876 bp product suggesting group A rotavirus. Besides virus isolation was successfully done using MA104 cell line.     

Electron microscopy in the diagnosis of viral gastroenteritis in hospitalised children in the Czech Republic

Our study has been aimed at demonstrating the main role of viruses in the aetiology of acute gastroenteritis in children less than 5 years old and at pointing out the diagnostic potential of electron microscopy in the diagnosis of viral gastroenteritis. A prospective study was conducted to analyse the aetiology of diarrhoeal diseases in children less than 5 years of age admitted to the Department of Infectious Diseases between September 2006 and December 2008. All children were tested by faecal culture, latex agglutination and electron microscopy. A total of 832 children were included in the study. An aetiological agent was detected in 788 children (94.6 %). A bacterial aetiology was found in 22 (2.6 %) children and bacterial–viral co-infection was found in 146 (17.6 %) patients. The most frequent causative agents of gastroenteritis in children were viruses, which were detected in 620 (74.5 %) patients. The main causes of viral gastroenteritis were rotaviruses (detected in 410 children), followed by caliciviruses (42), coronaviruses (28), adenoviruses (19) and astroviruses (14). Dual viral infections were detected in 107 children, with rotavirus–calicivirus co-infection being the most common. Electron microscopy proved to be a more sensitive method in comparison with the latex agglutination test for the diagnosis of rotaviruses and adenoviruses. The major role of viruses in diarrhoeal diseases among children under 5 years of age in the Czech Republic has been confirmed. The diagnostic potential of electron microscopy, particularly in small outbreaks of gastroenteritis, was clearly shown.     

Rotaviruses in younger children in Novosibirsk in 2005-2007: detection and genotyping

Examination of 1898 patients with acute enteric infection from March 2005 to February 2007 showed that group A rotaviruses were the most frequent cause (35%) of acute gastroenteritis among children under 3 years of age. Majority of cases of rotavirus infection was detected in infants under 1 year of age (71.8%). The peak of sporadic incidence was observed between February and May. High rate of mixed infection (45.6%) was observed - associations of rotaviruses with other viruses (noroviruses, astroviruses) and bacteria (Salmonella, Shigella, enteroinvasive Escherichia coli, Campylobacter, and opportunistic species) were detected. P- and G-genotypes of 337(50.8%) isolates of group A rotaviruses were determined by RT-PCR. The most prevalent strain was P[8]G1 (54.6%) followed by P[8]G3 (10.7%), P[8]G9 (8.6%), P[4]G2 (8.3%), and P[8]G4 (4.5%) genotypes.     

Genotypes of rotavirus associated with acute gastroenteritis in Seoul, Korea

Acute viral gastroenteritis is one of the most common infectious diseases in infants and young children. Rotavirus is mainly important in childhood. The present study determined the detection rate, seasonality and G and P genotypes of rotaviruses in children hospitalized for acute gastroenteritis in Seoul, Korea in 2009. A total of 1,423 stool specimens were screened by ELISA for the presence of rotavirus antigens and the rotavirus-positive stools genotyped by RT-PCR. The G genotype was determined for 90% of samples (242/269) and the P genotype for 93.3% (251/269). During the study, 25 G-P combinations were detected with G1P[8] in 38.3% (n= 103) and G4P[6] in 5.9% (n= 16) cases. These data provided information on rotavirus in patients with acute gastroenteritis in Seoul, Korea and provided baseline data to motivate for the implementation of control measures for rotavirus disease.     

Sequence analysis of gene 11 equivalents from "short" and "super short" strains of rotavirus

The molecular basis for the aberrant migration pattern of the gene 11 equivalent in rotaviruses with "short" (human DS-1) and "super short" (human 69M and bovine VMRI) electropherotypes was investigated. The mRNAs of these viruses were synthesized in vitro, and the entire gene 11 equivalent of each of these viruses was sequenced with specific synthetic oligonucleotide primers. These sequences were compared with previously published sequences of "long" pattern rotavirus gene 11 segments. The increased lengths of the gene 11 equivalents of DS-1, 69M, and VMRI are due to a prolonged, 3' untranslated region in this gene segment. The 3' untranslated region of the VMRI gene 11 equivalent contains a clear duplication of a portion of its coding sequence. A stretch of 18 consecutive nucleotides within the 330-nucleotide, 3' untranslated region of 69M is identical to a section of UK coding sequence. The DS-1 and the remainder of the 69M 3'-end additional sequences are similar to each other, but neither is similar to any other currently available rotavirus gene sequence. This finding suggests that a process other than homologous duplication is involved in the evolution of these sequences. The widespread occurrence of human and animal rotaviruses with short and super short electropherotypes provides evidence that intragenic and possibly intergenic recombinational events associated with an error-prone viral RNA polymerase may play a role in increasing the genetic repertoire of rotaviruses.     

Development of a rotavirus-shedding model in rhesus macaques, using a homologous wild-type rotavirus of a new P genotype

Although there are several reports on rotavirus inoculation of nonhuman primates, no reliable model exists. Therefore, this study was designed to develop a rhesus macaque model for rotavirus studies. The goals were to obtain a wild-type macaque rotavirus and evaluate it as a challenge virus for model studies. Once rotavirus was shown to be endemic within the macaque colony at the Tulane National Primate Research Center, stool specimens were collected from juvenile animals (2.6 to 5.9 months of age) without evidence of previous rotavirus infection and examined for rotavirus antigen. Six of 10 animals shed rotavirus during the 10-week collection period, and the electropherotypes of all isolates were identical to each other but distinct from those of prototype simian rotaviruses. These viruses were characterized as serotype G3 and subgroup 1, properties typical of many animal rotaviruses, including simian strains. Nucleotide sequence analysis of the VP4 gene was performed with a culture-grown isolate from the stool of one animal, designated the TUCH strain. Based on both genotypic and phylogenetic comparisons between TUCH VP4 and cognate proteins of representatives of the reported 22 P genotypes, the TUCH virus belongs to a new genotype, P[23]. A pool of wild-type TUCH was prepared and intragastrically administered to eight cesarean section-derived, specific-pathogen-free macaques 14 to 42 days of age. All animals were kept in a biocontainment level 2 facility. Although no diarrhea was observed and the animals remained clinically normal, all animals shed large quantities of rotavirus antigen in their feces after inoculation, which resolved by the end of the 14-day observation period. Therefore, TUCH infection of macaques provides a useful nonhuman primate model for studies on rotavirus protection.     

昆明婴幼儿腹泻的轮状病毒分子基因特征研究

目的了解昆明婴幼儿腹泻中轮状病毒感染情况。方法收集昆明医学院第一附属医院儿科2004年10-12月住院的腹泻的患儿粪便标本60份,采用聚丙烯酰胺凝胶电泳（PAGE）法和RT—PCR法进行轮状病毒分型。结果60份粪便标本中,29份检测到A组轮状病毒RNA基因,阳性检出率为48.3％,未发现B组及C组轮状病毒。其中RNA长型有29份（100％）,未发现短型和混合型。对29份有明确编号的轮状病毒阳性标本来源的患儿分析显示,平均发病年龄10.5个月。29份标本中,有20份可用RT—PCR分型,均为G3型,未发现其他型。结论A组轮状病毒是昆明地区5岁以下婴幼儿腹泻病的主要病原,3月龄-2岁婴幼儿是轮状病毒的易感人群,以冬季10月份至12月份为流行高峰,基因组以长型为主,血清型为G3型。     

Epidemiology and Evolution of Rotaviruses and Noroviruses from an Archival WHO Global Study in Children (1976–79) with Implications for Vaccine Design

Prompted by the discovery of new gastrointestinal viruses, the NIH, NIAID and WHO investigated the etiology of acute diarrhea that occurred from 1976–1979 in a global cohort of infants and young children. Rotaviruses were found to be major pathogens worldwide, whereas the Norwalk virus could not be detected using a radioimmunoassay. The aim of this study is to re-evaluate the role and diversity of rotaviruses and noroviruses in the original cohort using more sensitive current technologies. Stools collected from Asia, Africa, and South America (n = 485) were evaluated for viral genotypes by RT-PCR and sequencing. Rotaviruses were detected in 28.9% and noroviruses in 9.7% of the specimens, with G1 rotaviruses and GII noroviruses accounting for the majority of each respective virus. Various strains in this study predated the currently assigned dates of discovery for their particular genotype, and in addition, two noroviruses (KL45 and T091) could not be assigned to current genotypes. Phylogenetic analyses demonstrated a relative constancy in circulating rotavirus genotypes over time, with several genotypes from this study becoming established in the current repertoire of viral species. Similarly, GII noroviruses have maintained dominance, with GII.4 noroviruses continuing as a predominant genotype over time. Taken together, the complex molecular epidemiology of rotaviruses and noroviruses circulating in the 1970’s is consistent with current patterns, an important consideration in the design of multivalent vaccines to control these viruses.     

Acute diarrhoea in a community cohort of children who received an oral rotavirus vaccine in Northeast Brazil

Rotavirus is an important cause of childhood diarrhoea. A monovalent rotavirus vaccine (Rotarix?) was introduced into the Immunization Program of Brazil in 2006. In this study, we describe the incidence and burden of disease of rotavirus diarrhoea in two cohorts of children (vaccinated and unvaccinated). We followed two groups of 250 children under one year old, who were enrolled in December 2006 from a low-income residential area in Northeast Brazil. The children were monitored every two weeks for two years. Stool samples from children with diarrhoea were examined for the presence of rotavirus. Rotaviruses were genotyped using real time-polymerase chain reaction. The mean numbers of all-cause diarrhoea episodes/child (adjusted for age) in the first year were 0.87 and 0.84, in vaccinated and unvaccinated children, respectively. During the second year, the number of episodes/child decreased to 0.52 and 0.42. Only 16 (4.9%) of 330 stool samples were rotavirus-positive (10 vaccinated and 6 unvaccinated children) and only P[4]G2 rotaviruses were identified. All-cause diarrhoea episodes were more severe in unvaccinated children in the first year of age (p < 0.05), while vaccinated children had more severe episodes 18 months after vaccination. Rotavirus diarrhoea incidence was very low in both groups.     

Characteristic of the etiologic structure of acute enteric infections in adults based on the data from infectious diseases hospital

Study of the etiologic spectrum of sporadic cases of causative agents of acute enteric infections (AEI) in 753 patients aged 15-85 years old using polymerase chain reaction (PCR) was performed in the infectious diseases hospital during 12 months. It was shown that detection of the causative agents of AEI by PCR was 2.2 times more effective than routine microbiologic diagnostics supplemented with test of feces on rotavirus by ELISA method and allowed to detect etiologic agent in 54.3% of the patients. Viral etiology of AEI was determined in 22.6% of the patients. The most significant causative agents of AEI comparable on the rate of detection with salmonella and shigella were genotype 2 noroviruses and group A rotaviruses which were isolated in 10.4 and 8.9% of the patients respectively. Seasonal change of dominating viral pathogens causing diarrheal diseases was noted: predominance of group A rotaviruses during winter-spring period, noroviruses--during spring-summer months, and astroviruses--during fall and in the beginning of winter.