Four-year study of rotavirus electropherotypes from cases of infantile diarrhea in Rome

Prevalence of rotavirus-induced diarrhea among children under 5 years in Ilorin, Nigeria

Diarrhoea disease is an important cause of morbidity and mortality in Nigerian children and rotavirus has been identified as an important causative agent among children below 5 years. We determined the prevalence of rotavirus-induced diarrhoea among under-5 s by electrophenotyping. Stool samples were collected from eligible subjects who presented with acute diarrhoea. The samples were processed for viral studies by electrophenotyping. Among the 299 subjects recruited, 55.9% were positive for rotavirus. Eighty percent of the recruited patients were below 24 months. There was a significant decrease (p-value = 0.00001) in the prevalence of rotavirus among diarrhoea patients above the age of 24 months when compared with those below this age group. Rotavirus was associated with higher morbidity and mortality. We conclude that rotavirus is the most important cause of diarrhoea among children <5 years in Ilorin, Nigeria and its prevalence is highest in the first 2 years of life. Adequate rehydration should be regarded as the mainstay of management.

Rotavirus infection among children with diarrhoea in Italy

Despite the absence of a nationwide surveillance system for rotavirus infection, relevant information concerning the epidemiology of this pathogen in Italy can be obtained from hospital-based studies carried out since the early 1980s on patients with acute diarrhoea. A review of more than 50 papers and congress proceedings published in both international and national literature indicates that rotavirus is the most important cause of diarrhoea in Italy among young children requiring hospitalization, with a prevalence ranging from approximately 20% to 40% in different studies. Infection is predominant among children aged 6-24 months, although cases are also common in younger children and in children 2-3 y of age. Despite differences among studies in geographical area, years and age group under investigation, an increase in rotavirus cases is consistently reported in the winter months, with a peak in February through April. Although a few studies have been conducted in non-hospitalized patients, rotavirus infection is significantly less frequent among outpatients with enteritis than among inpatients. Most circulating rotavirus strains typed from 1981 to 1992 belong to serotype 1 and, to a lesser extent, 4. However, untypable rotavirus strains have been found in these years, with prevalences up to 27%, suggesting a possible spread of non-serotype 1 through 4 strains.

Burden of human rotavirus-associated hospitalizations in three geographic regions of Hungary

Data on hospital admissions and laboratory reports were used to estimate the number of hospitalizations of children aged 14 y or less in three geographic regions of Hungary due to group A rotavirus infection. Between January 1993 and December 1996, 9182 hospitalizations for gastroenteritis occurred, of which 1946 (21%) were associated with rotavirus infection. Most (90%) of the rotavirus detections were among children aged 4 y or less. By extrapolation, an estimated 5000 rotavirus-related hospitalizations (8.4/1000 children aged 4 y or less/y) occurred in Hungary during the study period. Marked seasonality of rotavirus infections was observed, with a peak of incidence from December to February. Rotaviruses with "long" RNA electropherotypes predominated each year, but in 1995/1996 20% of electropherotypes in the Budapest area were "short". Effective surveillance is required for all children hospitalized for diarrhoea as part of a rotavirus immunization program in Hungary.

Human rotavirus genomic RNA electropherotypes in Jeddah, Saudi Arabia from 1988 to 1992

Polyacrylamide gel electrophoresis was used to analyze the double-stranded RNA of rotavirus recovered from stool specimens collected between March 1988 and December 1992 from children with acute diarrhoea admitted to the central hospital in Jeddah, Saudi Arabia. Rotavirus was detected by ELISA in 523 specimens of the 1242 collected during the study, giving an overall prevalence of 42.2% for the 5 years of investigation. Out of 523 rotavirus-positive specimens, 263 (50.3%) were successfully electropherotyped. Eighteen different electropherotypes were observed, 12 long patterns and six short patterns. Eighty-seven per cent of the electropherotypes were of the long RNA pattern. The remaining were short electropherotypes. The predominant electropherotypes were two long patterns and maintained dominance over 5 years of the study. The third most predominant pattern was a short electropherotype. The remaining electropherotypes made minor contributions every year. These predominant electropherotypes were different from the predominant patterns detected in many countries. Temporal distribution was observed for 5 successive years for the predominant electropherotypes, with an increase in the incidence during the cooler months of the year.

The rotavirus genus

Human rotaviruses, discovered nearly 20 years ago, have been proven to be major cause of paediatric diarrhoeal disease morbidity and mortality. The clinical significance of these viruses stimulated basic studies on their biology, molecular and antigenic properties and epidemiology. General features, clinical relevance, epidemiologic pattern and laboratory diagnosis of human rotavirus infections are here reviewed.

Infectious diarrhoea. Viruses

Increased knowledge has been gained into the aetiology and pathogenesis of viral gastroenteritis during the past two decades. There are now thought to be four major subclassifications of gastroenteritis-causing viruses; these include rotavirus, enteric adenovirus, calicivirus, including Norwalk and Norwalk-like viruses, and astrovirus. The association of these agents with gastroenteritis has been made by their electron microscopic detection in stool and intestinal biopsy specimens from affected patients, the inability to detect the viruses after recovery from disease, and the subsequent development of immunoglobulin responses after infection; in some instances disease transmission was achieved in human volunteers. The association of these viral agents with gastroenteritis has facilitated the study of classification, epidemiology, immunity, diagnostic tests, methods of treatment and, most importantly, disease prevention strategies such as vaccine development for rotavirus. This chapter highlights the major features of these agents, with special attention being given to the pertinent molecular biology as well as current and future prospects for vaccination. Enteric viral infections of the gastrointestinal tract in patients with AIDS are also discussed.

Nosocomial transmission of rotavirus from patients admitted with diarrhea

We studied the transmission of rotavirus (RV) in 950 patients under 2 years of age hospitalized for diarrhea in Santiago, Chile. Stool samples were collected every other day from all patients during their entire hospital stay. To trace nosocomial transmission, we mapped the ward at the time of detection of RV. Comparative study by polyacrylamide gel electrophoresis of 315 RV isolates (180 detected upon admission of patients and 135 attributed to nosocomial transmission) allowed the identification of 18 different electropherotypes. An electropherotype similar to that of a community-acquired case was found in the same room in 81% of nosocomial cases and in the ward in 92% of nosocomial cases. It was concluded that the infants admitted shedding RV are the major source of nosocomial transmission and there was not a RV strain that was particularly transmissible.

Rotavirus e adenovirus em crianças de 0-5 anos hospitalizadas com ou sem gastrenterite em Goiânia - GO., Brasil

De junho/1987 a julho/1990 foram estudadas 557 amostras fecais de crianças hospitalizadas de 0-5 anos de idade, na cidade de Goiânia-GO., para detecção de rotavírus e adenovírus. Destas, 291 provinham de crianças diarréicas e 266 de não diarréicas. Das amostras não diarréicas, 64 eram provenientes de crianças de berçário. Das 557 amostras, 261 foram analisadas pela imunomicroscopia eletrônica (IME), eletroforese em gel de poliacrilamida (EGPA-SDS) e ensaio imunoenzimático para rotavírus e adenovírus (EIARA) e as demais apenas pela EGPA e EIARA. Rotavírus e adenovírus mostraram positividade de 17,2% e 2,1% respectivamente, e na condição de diarréia ou não, observou-se percentuais de 29,2% e 4,1% respectivamente para rotavírus (p<0,05) e 2,4% e 1,5% para adenovírus. Rotavírus foram mais prevalentes entre as crianças de 1-11 meses de idade e não foram vistos em nenhum recém-nato de berçário. Os adenovírus ocorreram na faixa de 1-3 anos. Rotavírus apresentaram maior circulação entre os meses de maio a agosto (p<0,05), não sendo encontrados de dezembro a fevereiro.

Importance of rotavirus and adenovirus types 40 and 41 in acute gastroenteritis in Korean children

To examine the role of rotavirus (Rv) and adenovirus types 40 and 41 (Ad40/41) in Korean children with acute gastroenteritis, we evaluated 345 children with acute gastroenteritis and 90 children without acute gastroenteritis in Seoul, Korea, during a 29-month period. Stools were tested for group A Rv antigen and for Ad40/41 by using monoclonal antibody (MAb)-based assays. Rv was found in 68% of the ill children and 19% of the controls (P less than 0.001), whereas Ad40/41 was detected in 9% of the ill children and 2% of the controls (P less than 0.05). Also, 6% of the ill children and 0.01% of the controls excreted Rv and Ad40/41 simultaneously. Among the ill children, 96% of children with Rv and 94% of those with Ad40/41 were younger than 24 months. Although a peak of Rv infection was detected in early winter in both years of the study, there was no apparent seasonal trend with Ad40/41. Diarrhea with more than 10 stools per day, vomiting, or fever was most strongly associated with Rv shedding, whereas the first two manifestations were associated with coinfection of Rv and Ad40/41. To investigate the genetic and serotypic diversity of Rv strains, we tested 195 and 144 fecal Rv specimens isolated from the gastroenteritis cases, respectively, by polyacrylamide gel electrophoresis of the segmented RNA genome and by an enzyme-linked immunosorbent assay with serotype-specific MAbs. Of the 195 specimens, 154 yielded RNA patterns characteristic of group A Rv: 18% had short electrophoretic migration patterns, 81% had long patterns, and 1% had a mixture of short and long patterns. Of the 144 specimens, serotype specificity was determined in 51%: 89% were serotype 1, 10% were serotype 2, and 1% were serotype 3. Analysis of the specimens for which electropherotypes and serotypes were available indicated that a given RNA pattern corresponded to a particular serotype, except in one strain that showed short patterns but serotype 1. We suggest that Rv and Ad40/41 in stools be accepted critically as an important cause of diarrhea among young children in Korea.

Some infectious causes of diarrhea in young farm animals

Escherichia coli, rotaviruses, and Cryptosporidium parvum are discussed in this review as they relate to enteric disease in calves, lambs, and pigs. These microorganisms are frequently incriminated as causative agents in diarrheas among neonatal food animals, and in some cases different strains or serotypes of the same organism cause diarrhea in humans. E. coli causes diarrhea by mechanisms that include production of heat-labile or heat-stable enterotoxins and synthesis of potent cytotoxins, and some strains cause diarrhea by yet undetermined mechanisms. Rotaviruses and C. parvum induce various degrees of villous atrophy. Rotaviruses infect and replicate within the cytoplasm of enterocytes, whereas C. parvum resides in an intracellular, extracytoplasmic location. E. coli, rotavirus, and C. parvum infections are of concern to producers, veterinarians, and public health officials. These agents are a major cause of economic loss to the producer because of costs associated with therapy, reduced performance, and high morbidity and mortality rates. Moreover, diarrheic animals may harbor, incubate, and act as a source to healthy animals and humans of some of these agents.