The spread of rotavirus gastroenteritis in the Republic of Tajikistan

The article deals with the results of the investigation which has demonstrated the spread of rotavirus infection on the territory of the Republic of Tajikistan. This infection has gained an important place in the regional pathology and requires increased epidemiological surveillance on its spread. As established in the course of this investigation, in patients with the clinical manifestations of pronounced gastroenteritis rotavirus plays the role of the etiological agent in 25.8% of cases in children aged up to 14 years and in 11.0% of cases in adults. Synchronism in the seasonal dynamics of morbidity in acute enteric infections of unclear etiology and rotavirus gastroenteritis among children aged 0-2 years, annually reaching morbidity peak in October, has been revealed. Rotavirus gastroenteritis requires close attention as regards its prophylaxis as one of the main nosological forms of acute enteric infections in the Republic.     

Molecular epidemiology and clinical characterization of group A rotavirus infections in Tunisian children with acute gastroenteritis

Rotaviruses are the most common cause of severe viral gastroenteritis in early childhood worldwide. Thus, the objectives of our study were to determine the molecular epidemiology and the clinical features of rotavirus gastroenteritis in Tunisia. Between January 2003 and April 2007, a prospective study was conducted on 788 stool samples collected from children under 12 years of age who were suffering from acute gastroenteritis. Rotavirus was detected by multiplex RT-PCR in 27% (n = 213) of samples, among them 79.3% (n = 169) cases were monoinfections. The frequency of rotavirus infections was significantly higher among inpatients (29%) than among outpatients (13%) (P < 0.001). The seasonal distribution of rotavirus diarrhea showed a winter peak, with an unusual peak from June to September. The mean duration of hospitalization was 6.5 ± 8.1 days and the mean age was 15.8 ± 22.8 months for rotavirus monoinfections. Fever, vomiting, abdominal pain, and dehydration were observed in 88, 98, 13, and 80 cases, respectively, in children with rotavirus monoinfections. G3P[8] (45.6%) and G1P[8] (23.9%) were the most common genotypes found in our study. The determination of rotavirus infection prevalence and the characterization of the rotavirus strains circulating will help us to better understand the molecular biology and epidemiology of the disease in our country.     

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.     

The epithelial cell response to rotavirus infection.

Rotavirus is the most important worldwide cause of severe gastroenteritis in infants and young children. Intestinal epithelial cells are the principal targets of rotavirus infection, but the response of enterocytes to rotavirus infection is largely unknown. We determined that rotavirus infection of HT-29 intestinal epithelial cells results in prompt activation of NF-kappaB (<2 h), STAT1, and ISG F3 (3 h). Genetically inactivated rotavirus and virus-like particles assembled from baculovirus-expressed viral proteins also activated NF-kappaB. Rotavirus infection of HT-29 cells induced mRNA for several C-C and C-X-C chemokines as well as IFNs and GM-CSF. Mice infected with simian rotavirus or murine rotavirus responded similarly with the enhanced expression of a profile of C-C and C-X-C chemokines. The rotavirus-stimulated increase in chemokine mRNA was undiminished in mice lacking mast cells or lymphocytes. Rotavirus induced chemokines only in mice <15 days of age despite documented infection in older mice. Macrophage inflammatory protein-1beta and IFN-stimulated protein 10 mRNA responses occurred, but were reduced in p50-/- mice. Macrophage inflammatory protein-1beta expression during rotavirus infection localized to the intestinal epithelial cell in murine intestine. These results show that the intestinal epithelial cell is an active component of the host response to rotavirus infection.     

Childhood gastroenteritis: a population study.

A prospective study of gastroenteritis based on a population was carried out for 12 months on over 7000 children in general practice. The incidence of gastroenteritis was highest in the first year (127.7 children affected per 1000) and second year (90.8) of life, and gastroenteritis was rare after six years of age. Children from urban areas had gastroenteritis more commonly than children from semirural areas. A potential pathogen was isolated from half of the specimens: 78% were viruses, and rotavirus was identified most often.     

Water-borne outbreaks of rotavirus infections

The clinico-epidemiological characteristics of group rotavirus infection observed in one settlement in March-April is presented. 173 cases of infection were registered in all age groups (children under 7 years constituted only 10.4% of the patients). In most of the apartments found to be the foci of infection only one patient was registered. The virological study of fecal samples from 24 patients showed the presence of human rotaviruses in the feces of 10 patients (41.7%). Neutralizing antibodies in titers of 1:4 to 1:64 were detected in all taken paired sera (21). THe clinical study of 53 hospitalized patients showed that in all cases the infectious process had acute beginning. In most patients the disease took mild forms. The peculiarities of the distribution of the patients in different age groups, the location of the foci of infection and its seasonal character, as well as some objective data on the presence of pollutions in the water mains, indicated that this infection could spread through water via the system of centralized water supply.     

Novel probiotic Bifidobacterium longum subsp. infantis CECT 7210 strain active against rotavirus infections

Rotavirus is the leading cause of severe acute gastroenteritis among children worldwide. It is well known that breast-feeding and vaccination afford infants protection. Since breast-feeding has drastically decreased in developed countries, efforts have been focused on the potential use of probiotics as preventive agents. In this study, a novel Bifidobacterium longum subsp. infantis strain was isolated from infant feces and selected, based on its capacity to inhibit in vitro rotavirus Wa replication (up to 36.05% infectious foci reduction) and also to protect cells from virus infection (up to 48.50% infectious foci reduction) in both MA-104 and HT-29 cell lines. Furthermore, studies using a BALB/c mouse model have proved that this strain provides preliminary in vivo protection against rotavirus infection. The strain has been deposited in the Spanish Type Culture Collection under the accession number CECT 7210. This novel strain has the main properties required of a probiotic, such as resistance to gastrointestinal juices, biliary salts, NaCl, and low pH, as well as adhesion to intestinal mucus and sensitivity to antibiotics. The food safety status has been confirmed by the absence of undesirable metabolite production and in acute ingestion studies of mice. Overall, these results demonstrate that Bifidobacterium longum subsp. infantis CECT 7210 can be considered a probiotic able to inhibit rotavirus infection.     

长春地区冬季流行的轮状病毒核酸电泳型的比较

轮状病毒是婴幼儿腹泻的主要病原,在我国亦广泛流行,根据病毒基因组的电泳分析,可以研究其分子流行病学的规律。文献报道该病毒在流行区往往以一个电泳型感染为主,我们对长春地区1984～1985年和1985～1986年两个冬季流行的婴幼儿腹泻轮状病毒基因组PAGE分析的结果,也表明两个冬季都是以电泳长型感染为主,其中优势株与本室     

A survey of rotavirus infection in the topics

The age distribution of rotavirus antibody in the serum of inhabitants of Laos and Indonesia was studied by the neutralization test using antigenically related calf rotavirus (NCDV) as a substitute for non-cultivable human rotavirus. The results revealed that both the rate of antibody-positives and the modal titers of antibody distribution by each age group in these countries were higher than those in respective are groups of Japanese, which suggest higher endemicity of rotavirus infection in these countries. A survey of rotavirus in diarrheic patients' stools by enzyme-linked immunosorbent assay indicated that the virus infection occurred most frequently among infants between 4 and 12 months of age.     

Evaluation of a latex agglutination test for rapid detection of rotavirus in faecal specimens

Two methods for detecting rotaviruses (latex agglutination, electron microscopy) have been compared on 80 faecal samples. These samples were obtained from infants between the age of four and 30 months hospitalized for acute gastroenteritis in the Children's Hospital, Karl Marx University at Leipzig, in 1982. Complete agreement among the two techniques was found in 75 specimens. Sensitivity of latex agglutination could be estimated at 95%, the specificity also at 95%. Only one sample reacted nonspecifically. Performance of the latex agglutination proved quite simple. The results indicate that latex agglutination is suitable for rapid screening of rotavirus induced gastroenteritis in clinical practice thus enabling the rate of nosocomial rotavirus infections in children's hospitals to be reduced.     

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.     

Gastroenteritis in suckling mice caused by human rotavirus can be prevented with egg yolk immunoglobulin (IgY) and treated with a protein-bound polysaccharide preparation (PSK)

Oral inoculation of human rotavirus MO strain (serotype 3) into 5-day-old BALB/c mice cause gastroenteritis characterized by diarrhea. Clinical symptoms, histopathological changes in the small intestine, and the detection of rotavirus antigen in enterocytes were all characteristic of rotavirus-induced gastroenteritis. Using this small animal model, passive protection of suckling mice against human rotavirus infection was achieved with the use of immunoglobulin (IgY) from the yolks of eggs of rotavirus-immunized hens. When IgY against a rotavirus strain homotypic to the challenge virus (MO strain) was administered in the mice, complete protection against rotavirus infection was achieved. On the other hand, with oral administration of IgY against a heterotypic strain (serotype 1, Wa strain), a lower protective effect was nevertheless obtained. The four different strains of human rotavirus (Wa, KUN, MO, and ST3) were inactivated in vitro by treatment with PSK, a protein-bound polysaccharide preparation, in a dose-dependent manner. Oral administration of 2.5 mg of PSK caused a therapeutic effect on experimentally MO-infected suckling mice. The antiviral effect of PSK was indicated by the reduction of the duration of diarrhea.     

In vitro neutralisation of rotavirus infection by two broadly specific recombinant monovalent llama-derived antibody fragments

Rotavirus is the main cause of viral gastroenteritis in young children. Therefore, the development of inexpensive antiviral products for the prevention and/or treatment of rotavirus disease remains a priority. Previously we have shown that a recombinant monovalent antibody fragment (referred to as Anti-Rotavirus Proteins or ARP1) derived from a heavy chain antibody of a llama immunised with rotavirus was able to neutralise rotavirus infection in a mouse model system. In the present work we investigated the specificity and neutralising activity of two llama antibody fragments, ARP1 and ARP3, against 13 cell culture adapted rotavirus strains of diverse genotypes. In addition, immunocapture electron microscopy (IEM) was performed to determine binding of ARP1 to clinical isolates and cell culture adapted strains. ARP1 and ARP3 were able to neutralise a broad variety of rotavirus serotypes/genotypes in vitro, and in addition, IEM showed specific binding to a variety of cell adapted strains as well as strains from clinical specimens. These results indicated that these molecules could potentially be used as immunoprophylactic and/or immunotherapeutic products for the prevention and/or treatment of infection of a broad range of clinically relevant rotavirus strains.     

Inhibitory effects of bile acids and synthetic farnesoid X receptor agonists on rotavirus replication

Rotaviruses (group A rotaviruses) are the most important cause of severe gastroenteritis in infants and children worldwide. Currently, an antiviral drug is not available and information on therapeutic targets for antiviral development is limited for rotavirus infection. Previously, it was shown that lipid homeostasis is important in rotavirus replication. Since farnesoid X receptor (FXR) and its natural ligands bile acids (such as chenodeoxycholic acid [CDCA]) play major roles in cholesterol and lipid homeostasis, we examined the effects of bile acids and synthetic FXR agonists on rotavirus replication in association with cellular lipid levels. In a mouse model of rotavirus infection, effects of oral administration of CDCA on fecal rotavirus shedding were investigated. The results demonstrate the following. First, the intracellular contents of triglycerides were significantly increased by rotavirus infection. Second, CDCA, deoxycholic acid (DCA), and other synthetic FXR agonists, such as GW4064, significantly reduced rotavirus replication in cell culture in a dose-dependent manner. The reduction of virus replication correlated positively with activation of the FXR pathway and reduction of cellular triglyceride contents (r(2) = 0.95). Third, oral administration of CDCA significantly reduced fecal virus shedding in mice (P < 0.05). We conclude that bile acids and FXR agonists play important roles in the suppression of rotavirus replication. The inhibition mechanism is proposed to be the downregulation of lipid synthesis induced by rotavirus infection.     

Serum and cerebrospinal fluid nitrite/nitrate levels in patients with rotavirus gastroenteritis induced convulsion

Nitric oxide (NO) is a highly reactive free radical that is involved in a variety of different biological process. In recent reports, the putative role of NO in the neuropathogenesis of brain inflammation has been demonstrated. And then the relation between neuronal NO and convulsive seizures induced by virus has been suggested. However, there are few reports about NO in vivo under viral neurological infections. In order to evaluate the relation between NO production and neurological disorders induced by viral infection, sixty-six cases including 11 patients with rotavirus gastroenteritis admitted for convulsions were examined in this study. NO metabolites (NOx) levels in both serum and cerebrospinal fluid obtained from rotavirus gastroenteritis patients with convulsion were much higher than in those of patients with purulent meningitis, encephalitis, febrile convulsion or in the control group. There was a relative correlation between IL-6 and NOx in some cases. These results indicated that NO may have a pathophysiological role in convulsions associated by rotavirus infection either through indirect or direct effects of NO. Consequently, NOx inhibitors might be helpful for the treatment of rotavirus encephalopathy.     

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.     

Comparison of ELISA with shell vial cell culture method for the detection of human rotavirus in fecal specimens

The aim of the study was to compare an enzyme immunoassay method with shell vial cell culture method for detection of rotavirus in fecal specimens. In addition, the correlation between laboratory results and clinical scores of patients with gastroenteritis was evaluated. A total of 219 fecal specimens from children (ages 3 weeks to 5 years) with acute gastroenteritis submitted to pediatric emergency room were evaluated by both ELISA and shell vial cell culture. A Vesikari score was used for assessing the severity of the illness. Among 219 stool samples tested, 107 (48.9%) were determined to be positive. Two specimens were positive by shell vial cell culture method while they were ELISA negative. According to these results the calculated sensitivity, specificity, PPV, and NPV of ELISA were 98.1%, 100%, 100%, and 98.2%, respectively. The mean severity score for the 107 episodes of rotavirus diarrhoea was 11.0 +/- 3.6 compared to 4.5 +/- 1.9 for the 112 episodes of non-rotavirus diarrhea in the same population. Our study indicates that ELISA, which is easier to perform, faster and cheaper than cell culture methods may be suitable for routine diagnosis of rotavirus infections. The severity of rotavirus positive gastroenteritis was significantly higher than that of rotavirus negative patients.