Rotavirus infections in newborns: an epidemiological and clinical study

An outbreak of rotavirus infections among newborns at Karolinska Hospital, Stockholm, which has been going on for greater than 2 years has been followed with clinical and epidemiological investigations. About one third of the babies born in the hospital were infected at the age of 3 days. The clinical symptoms were mild, 8.8% of the rotavirus positive babies had loose stools compared to 1.9% of those who did not excrete the virus. An epidemiological survey in the neonatal intensive care unit suggested that rotavirus was introduced into the unit by babies admitted from the obstetric wards. The main reservoir of rotavirus was the babies and rotavirus was not found among staff or mothers. In the beginning hygienic measures seemed to be effective but after some weeks the colonization rate again increased. Electropherotyping of samples collected during different periods showed that one single rotavirus electropherotype belonging to the subgroup 1 of human rotavirus was found throughout the outbreak.     

被动免疫预防犊牛轮状病毒感染的研究

目的 轮状病毒灭活疫苗免疫孕牛后，研究产下犊牛通过母源抗体获得的被动免疫在预防牛轮状病毒感染中的作用。方法 孕牛产前2月和1月分别接种轮状病毒灭活疫苗，检测产牛后乳汁和犊牛血样中BRV特异性IgG、IgA及中和抗体滴度。犊牛21日龄时口服2mL10^4,59 TCID50／ml的牛轮状病毒，观察犊牛腹泻及排毒情况。结果 免疫组乳清和犊牛血清中产生了高水平的牛轮状病毒特异性IgG、IgA及中和抗体，与对照组差异极显著（P〈0．01）；攻毒后，对照组6头犊牛全部发生腹泻，免疫组6头中有1头腹泻，发病的潜伏期及发病率差异显著。结论 被动免疫可显著提高犊牛血清中牛轮状病毒特异性抗体水平，使犊牛获得一定的免疫保护力抵抗轮状病毒的感染。     

Protection of Peruvian children against rotavirus diarrhea of specific serotypes by one, two, or three doses of the RIT 4237 attenuated bovine rotavirus vaccine

A randomized placebo-controlled double-blind field trial of RIT 4237 attenuated rotavirus vaccine in Lima, Peru, evaluated the protection against diarrheal illness by one, two, or three doses of vaccine. There were 391 children, 2-18 months old, studied for the occurrence of diarrhea during the 18 months after vaccination. Three doses of the vaccine provided 40% protection against any diarrheal illness associated with rotavirus alone but 58%-75%; protection against the more severe rotaviral illnesses. The vaccine appeared to be more efficacious when it was administered to children in the first year of life. Three doses provided up to 89% efficacy against more severe diseases due to serotype 1 rotavirus, and one dose also afforded significant protection. The protection was lower, even with three doses, against serotype 2 rotavirus. This vaccine trial has provided important insights on how such trials should be conducted and on the serotype-specificity of protection from rotavirus infection. Future vaccines should be able to protect against severe disease caused by all rotavirus serotypes and must work in developing countries where rotavirus is the most important cause of diarrheal mortality.     

Clinical and immunological studies of rotavirus vaccines

The RIT 4237 bovine rotavirus vaccine has served as a useful model for rotavirus vaccination, but the vaccine will not be further developed or tested. The main problem encountered with this vaccine was its poor "take" rate in developing countries. The reasons for this are unclear, and it is not known whether other bovine rotavirus vaccines are more efficacious in this respect. WC-3 bovine rotavirus vaccine will shortly be tested at several sites in developing countries. The rhesus rotavirus vaccine RRV-1 does not appear by itself to be a practical vaccine either. It has induced only moderate protection against human rotavirus serotypes other than the vaccine type. However, the fact that RRV-1 vaccine has induced substantial protection against severe diarrhoea caused by serotype 3 rotavirus, even in young infants, is promising and supports the concept that serotype-specific neutralizing antibodies play a role in protection against human rotavirus disease. Based on this concept, it has been possible to develop reassortant rhesus rotaviruses in which one RNA segment of human rotavirus, which encodes the expression of VP7 antigen, has been incorporated (Kapikian et al., 1986; 1987). Such rhesus-human reassortant rotaviruses, representing serotypes 1, 2 and 4 of human rotavirus and serotype 3 of rhesus rotavirus, can be combined to make a tetravalent vaccine that might induce neutralizing antibodies against each of the main serotypes of human rotavirus. Although its efficacy is unproven, such a combination vaccine is presently regarded as the most promising candidate rotavirus vaccine for the prevention of human rotavirus disease.     

Diarrhea associated with rotavirus in rural Guatemala: a longitudinal study of 24 infants and young children.

A population of 24 infants and young children followed prospectively during the first 3 years of life was studied for the occurrence of rotavirus infection by using enzyme-linked immunosorbent assay to detect virus in stools. Infection with rotavirus was associated with 26 (14.2%) of 183 selected diarrheal episodes. Twenty of the 24 infants and young children had diarrhea associated with rotavirus on at least one occasion and six had two such episodes. Rotavirus infection was documented in over 50% of the dehydrating episodes studied, thus further indicating the importance of rotavirus in this population.     

Oral administration of human rotavirus to volunteers: induction of illness and correlates of resistance

Four of 18 volunteers challenged orally with human rotavirus strain D (subgroup 2, serotype Wa) developed a diarrheal illness two to four days after inoculation. Viral shedding was detected in five of the 18 volunteers, whereas 12 (67%) developed serologic evidence of infection. Two volunteers who developed diarrheal illness after the initial inoculation were given the same inoculum 19 months later; neither developed diarrhea, although one developed constitutional and gastrointestinal symptoms. The presence of preinoculation serum immunofluorescent antibody to rotavirus strain D or high levels of neutralizing antibody to Wa or reassortant DS-1 human rotavirus correlated with resistance to diarrheal illness. Although prechallenge serum antibody correlated with resistance to diarrhea and/or shedding of rotavirus, the relationship of preexisting local neutralizing activity in intestinal fluid was less clear-cut.     

Virus-specific IgM antibodies in acute gastroenteritis due to a reovirus-like agent (rotavirus).

62 serum samples from 24 patients with rotavirus gastroenteritis were tested for IgM antibodies against a bovine rotavirus by an indirect fluorescent antibody technique. IgM antibodies were detected in one or more of the serum samples from all but one of the patients. IgM antibodies were not detected in samples obtained from 11 of the patients after the 5th week of illness. Absorption of sera for IgG with Staphylococcus aureus increased the sensitivity of the IgM antibody test. It is concluded that the presence of IgM antibodies against bovine rotavirus in a patient's serum, as measured by the present technique, does suggest a recent rotavirus infection. On the other hand, the lack of IgM antibodies in the serum of a child with acute gastroenteritis between the second and the 5th week of illness tends to exclude rotavirus as a cause of the disease.     

Rotavirus and adenovirus in 0- to 5-year-old children hospitalized with or without gastroenteritis in Goiana, GO, Brazil]

In order to detect rotavirus and adenovirus 557 feces samples from hospitalized children (0-5 years of age) were analysed from June 1987 to July 1990 in Goiania city. Two hundred and ninety one samples were from children with diarrhoea and 266 were from children without diarrhoea. Amongst this later group, 64 samples were from children from the nursery. Two hundred and sixty one out of 557 samples were analysed by immunoelectron microscopy (IEM), polyacrylamide gel electrophoresis (SDS-PAGE) and enzymatic immunoassay for rotavirus and adenovirus (EIARA) whereas the rest (296 samples) were analysed by SDS-PAGE and EIARA. Positivity of rotavirus and adenovirus was 17.2% and 2.1% respectively. Concerning rotavirus and adenovirus there was 29.2% and 2.4% positivity within the group with diarrhoea and 4.1% and 1.5% positivity amongst children without diarrhoea (p < 0.05). Rotavirus were more prevalent amongst children which age ranged from 1 to 11 months of age. No newborn child from the nursery was positive for rotavirus. Adenovirus were detected amongst children from 1 to 3 years of age. Rotavirus circulation peak occurred between May and August (p < 0.05) and no positive case was detected from December to February. Two hundred out of 291 diarrheic samples were also studied concerning bacteria and pathogenic parasites and equal percentages (17.0%) were found for both rotavirus and pathogenic bacteria. Eighty nine samples of rotavirus were detected by SDS-PAGE and 86 of these (96.6%) belonged to the subgroup II with 13 different electrophoretic patterns. Predominance of a given electrophoretic profile was observed in each year of the study.     

人轮状病毒持续感染病毒株的生物学特性

本文研究了人轮状病毒持续感染细胞系——Mads-105细胞系所产生的病毒的有关生物学特性,发现该病毒仍有较强的致细胞病变能力,形态与普通人轮状病毒相同,未发现自身干扰现象和温度敏感突变,有意义的是胰蛋白酶处理病毒与否和维持液中是否含有胰蛋白酶,均对该病毒在MA-104细胞中的增殖无显著影响,表明持续感染细胞系所产生的病毒对胰蛋白酶的依赖性已发生突变,这可能由于持续感染细胞长期受新生牛血清影响所致,亦可能是造成持续感染的机制。     

Antigenic relationships among human rotaviruses as determined by outer capsid protein VP4.

cDNA clones representing the VP4 gene of symptomatic human rotavirus strain KU (VP7 serotype 1) or DS-1 (VP7 serotype 2) or asymptomatic human rotavirus strain 1076 (VP7 serotype 2) were constructed and inserted into a baculovirus expression vector under the control of the polyhedrin promoter. The resulting recombinants expressed the appropriate authentic VP4 rotavirus outer capsid protein. Guinea pigs immunized with these VP4 proteins developed antibodies that neutralized infectivity of the rotavirus from which the immunizing VP4 was derived. These antisera were then used in neutralization tests to define the extent and distribution of VP4 antigenic polymorphism among human rotaviruses. Three distinct serotypes and one subtype of the VP4 outer capsid protein were identified among 17 human rotavirus strains that had previously been assigned to five distinct VP7 serotypes. For the most part, VP4 serotype segregated independently of VP7 serotype. Ten strains of human rotavirus that were associated with symptomatic infection and that exhibited VP7 serotype 1, 3, 4, or 9 specificity, each possessed a VP4 of the same serotype and subtype, designated VP4 serotype 1A. Both symptomatic human rotavirus strains with VP7 serotype 2 specificity were related by neutralization to the VP4 serotype 1A strains and were classified as a subtype of VP4 serotype 1--i.e., serotype 1B--since viruses of serotype 1A appeared to be prime strains. Four human rotavirus strains that were recovered from healthy infants in newborn nurseries in which virus transmission persisted over a long interval, belonged to VP7 serotype 1, 2, 3, or 4, but each strain possessed the same VP4 antigenic specificity that was designated VP4 serotype 2. Finally, a single strain of symptomatic human rotavirus of VP7 serotype 1 specificity possessed a unique VP4 that was provisionally classified as VP4 serotype 3 but this remains to be confirmed because neutralization tests were performed in only one direction. Among the 10 rotavirus strains whose VP4 gene was previously sequenced, there was complete concordance between assignment of VP4 serotype by neutralization and classification according to VP4 amino acid homology. Thus, rotaviruses that exhibited a VP4 amino acid homology of 89% or greater belonged to the same VP4 serotype and subtype as determined by neutralization. Finally, evidence was obtained that the serotype-specific domain is located on the VP8 subunit of VP4.     

Epidemiological study of group C rotavirus

By electron microscopy survey of acute gastroenteritis of children in Matsuyama, rotaviruses were detected in 561 of 2479 fecal samples obtained between October, 1984 and September, 1988, in which 60 atypical and 259 typical rotaviruses, so far tested, were detected by polyacrylamide gel electrophoresis (PAGE) of viral RNA. Out of 60 atypical rotaviruses, 5 were observed in 1985, 7 in 1986, none in 1987 and 48 in 1988. These atypical rotaviruses were morphologically indistinguishable from typical ones and showed very similar RNA migration patterns of PAGE to those of group C rotavirus. Furthermore, one atypical virus (86-542) reacted with antiserum against a porcine group C rotavirus in immune electron microscopy, while it did not react with anti-group A rotavirus serum. On the other hand, hyperimmune guinea pig antiserum against 86-542 reacted with a couple of atypical rotavirus including viruses isolated in 1988, so far tested, but did not react with any of the typical viruses. These findings showed that atypical rotaviruses which were endemic in Matsuyama city in 1988 were defined as group C rotavirus. Moreover, these group C rotaviruses showed two kind of RNA migration patterns in PAGE, which clearly discriminated the virus were isolated before and after 1987. Epidemiological features of group C rotavirus were as follows. Children from whom group C rotavirus was isolated were older than those from of whom group A rotavirus was isolated. The epidemic season was in February through April, compared to December through March in group A virus. Retrospective seroepidemiological study by immune adherence hemagglutination test (IAHA) using the purified 86-542 virus as antigen indicated that 15 of 78 sera of children obtained in 1971 already possessed IAHA antibody against group C rotavirus.     

福州地区腹泻患者诺瓦克样病毒感染的分子流行病学特点

目的调查研究福州地区腹泻患者诺瓦克样病毒感染的分子流行病学特点。方法分别应用酶联免疫吸附试验(ELISA)和逆转录一聚合酶链反应(RT-PCR)，对1998年10月至2002年11月在我院门诊及住院部收集的288份腹泻患者粪便标本进行轮状病毒和诺瓦克样病毒病原检测。结果ELISA法检测轮状病毒感染的阳性率为54．2％，发病年龄主要是1月-3岁的婴幼儿，发病季节集中在冬春季，高峰为11和12月份。RT-PCR检测显示诺瓦克样病毒基因组Ⅰ的阳性率为11．1％，主要是7岁以上儿童及成人；诺瓦克样病毒基因组Ⅱ的阳性率为28．8％，主要是6月～3岁婴幼儿；诺瓦克样病毒感染均无明显季节特异性。结论在福州地区诺瓦克样病毒是仅次于轮状病毒的又一常见腹泻病原，其中婴幼儿腹泻以诺瓦克样病毒基因组Ⅱ为主。研究结果从分子水平初步揭示了本地区诺瓦克样病毒感染的流行情况。     

Clinical profile and prevalence of rotavirus infection in children presented with acute diarrhea at tertiary care referral hospital at northern part of India

A prospective analysis of 90 clinically diagnosed cases with acute diarrhea over a period of one year was carried out to determine the prevalence of rotavirus infection in children between 2 months to 2 years of age. Enzyme Linked Immunosorbent Assay (ELISA) and Polyacrylamide Gel Electrophoresis (PAGE) were used for detection of rotavirus from stool sample. Fourteen (15.6%) of them were found to be positive for group A rotavirus, 9 (23%) cases were between 6 months to 1 year of age. Rotavirus excretion was highest (50%) when all three symptoms (diarrhea, vomiting and fever) occurred in the same child. A planned study for surveillance of rotavirus serotypes is required from this area.     

The present status of rotavirus vaccine development

Rotavirus infection is one of the most important causes of morbidity in young children throughout the world. The high associated mortality in Southeast Asia (and elsewhere) warrants the development of a vaccine. It is probable that most of the life-threatening watery diarrhoea due to rotavirus infection occurs as a result of primary infection in children aged 6-18 months after protection due to maternal antibody has diminished. Thus rotavirus vaccines are targeted at young infants from birth to 3 months of age. At present three candidate rotavirus vaccines (RIT-4237, MMU-18007, WC3) have undergone trials in young children. A bovine rotavirus strain (RIT-4237), was shown to be safe, immunogenic and efficacious in prevention of severe rotavirus diarrhoea in young children in Finland. However it was found to be weakly immunogenic in infants in developing countries, and to have only low efficacy in prevention of disease. A simian rotavirus strain (RRV, MMU-18006) has proved to be highly immunogenic and its reactinogenicity to be diminished by pre-existing maternal antibody (in infants aged 1-4 months). It has high efficacy against clinically severe rotavirus infection. However protection is homotypic against human serotype 3 only so that eventually a multivalent vaccine incorporating reassortant rotavirus strains that protect against human serotypes 1, 2, 4 (and other newer serotypes) may be required. It is hoped that, once safe immunogenic and protective candidate rotavirus vaccines are identified, they can be administered in an acceptable form with no alteration to existing immunization schedules.     

圆片法ELISA检测腹泻患儿粪便中轮状病毒抗原的研究

本文叙述一种改进的酶联免疫吸附试验(ELISA),采用圆片作为高容量的固相载体,以目测法检测轮状病毒抗原。圆片用兔抗轮状病毒IgG包被,在2℃～8℃中贮存,至少1月仍保持稳定性。Discs-ELISA对轮状病毒抗原的检出灵敏度比聚苯乙烯作为固相载体的传统ELISA所取得的结果高。Discs-ELISA采用未提纯的粪便抗原,其敏感性高,易于操作,是一种有效而快速诊断轮状病毒抗原的方法。     

Rotavirus-associated gastroenteritis in two adults probably caused by virus reinfection.

Rotavirus infection was diagnosed by virus detection and by serological methods in 2 women with acute gastroenteritis, aged 22 and 29 years, respectively. Both patients had been in close contact with children with rotavirus gastroenteritis. Rotavirus-specific antibodies were detected in serum specimens obtained prior to the illness in one of the patients, and the serological response in both patients suggested a reinfection with rotavirus as cause of the disease.     

Treatment of rotaviral gastroenteritis with Qiwei Baizhu powder

AIM To observe the effects of Qiwei Baizhu Powder(QWBZP)on rotaviral gastroenteritis in children and inanimal models.METHODS Enrolled patients were divided into twogroups,and one group was treated with oral rehydrationsolution(ORS)and the other treated with oral liquid ofQWBZP.Neonate mice were orally infected with 50μLrotavirus suspension(4×10~8 PFU/mL)and treated withORS or oral liquid of QWBZP,respectively.RESULTS Eighty-three cases of rotaviral gastroenteritistreated with QWBZP revealed a better efficacy than thattreated with ORS(X~2=10.87,P<0.05).The contents ofsodium and glucose as well as number of patients withpositive human rotavirus antigen in stool in QWBZP groupwere all less than that in ORS group.In animal models,QWBZP was found effective in treating rotavirusgastroenteritis in neonate NIH mice,as compared withcontrol groups.In QWBZP group,the mortality of infectedmice was decreased by 73.3%,the body weight ofinfected mice was increased,the contents of sodium andglucose as well as number of mice with positive rotavirusantigen in feces were significantly reduced,and thepathological changes such as damage of small intestinalmucosa and villi were also obviously alleviated.CONCLUSION QWBZP has effects on improving theabsorptive function of small intestine,shortening theduration of diarrhea and rotavirus shedding from stool andalleviating the pathological changes of small intestineinduced by rotavirus.     

Estimation of annual incidence, age-specific incidence rate, and cumulative risk of rotavirus gastroenteritis among children in Japan

Rotavirus gastroenteritis is a common childhood infection, but the exact morbidity of the disease is not well described in Japan. We aimed at estimating morbidity measures to determine the magnitude of rotavirus gastroenteritis. An estimate for acute infectious gastroenteritis of all causes, to which rotavirus gastroenteritis belongs, has been available since the enactment in 1999 of the Law concerning the Prevention of Infectious Diseases and Medical Care of Patients with Infectious Diseases. Using this estimate and another estimate for the detection proportion of rotavirus among outpatients with acute infectious gastroenteritis, we calculated the annual incidence, the age-specific annual incidence rate, and the cumulative risk by the age of 6 years for rotavirus gastroenteritis. The latter estimate was obtained by a meta-analysis of four independent studies previously performed in Japan. According to our estimates, approximately 800,000 children in Japan under the age of 6 years visit pediatric practices or the outpatient department of hospitals because of rotavirus gastroenteritis at a rate of 11 cases/100 persons/year, and one in two children will visit pediatricians before they go to primary school. Such pediatrician visits most frequently occur at the age of 1 year (27 cases/100 persons/year). Thus, the magnitude of the burden of rotavirus disease among Japanese children is substantial.     

Effect of Infant and Maternal Secretor Status on Rotavirus Vaccine Take—An Overview

Histo-blood group antigens, which are present on gut epithelial surfaces, function as receptors or attachment factors and mediate susceptibility to rotavirus infection. The major determinant for susceptibility is a functional FUT2 enzyme which mediates the presence of α-1,2 fucosylated blood group antigens in mucosa and secretions, yielding the secretor-positive phenotype. Secretors are more susceptible to infection with predominant rotavirus genotypes, as well as to the commonly used live rotavirus vaccines. Difference in susceptibility to the vaccines is one proposed factor for the varying degree of efficacy observed between countries. Besides infection susceptibility, secretor status has been found to modulate rotavirus specific antibody levels in adults, as well as composition of breastmilk in mothers and microbiota of the infant, which are other proposed factors affecting rotavirus vaccine take. Here, the known and possible effects of secretor status in both infant and mother on rotavirus vaccine take are reviewed and discussed.     

Rotavirus Causes Hepatic Transaminase Elevation

Rotavirus is one of the leading causes of acute gastroenteritis among children. While clinical complaints are generally intestinal including vomiting and diarrhea, there is evidence to suggest that disease outside the gastrointestinal tract occurs. This study examines the frequency of hepatic transaminase elevation in children with rotavirus gastroenteritis. Patients identified with rotavirus gastroenteritis by stool antigen testing between November 2005 and March 2006 had available serum analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, total bilirubin, direct bilirubin, and creatinine phoshosphokinase (CPK). Chart review was conducted to identify patients with possible liver injury unrelated to rotavirus. Among the 92 patients identified with rotavirus during the study period, 75 had serum specimens available for testing. Fifteen patients (20%) had elevated ALT and AST, including one patient with an increase in AST, ALT, alkaline phosphatase, and total and direct bilirubin. The mean ALT elevation was 56 IU/L (range, 44 to 114 IU/L), and the mean AST elevation was 80 IU/L (range, 57 to 126 IU/L). Fifty-three patients (71%) had an increase in AST alone, and three patients (4%) had an increase in AST and alkaline phosphatase. The mean AST values in these groups were 61 IU/L (range, 42 to 110 IU/L) and 79 IU/L (range, 59 to 96 IU/L), respectively. In conclusion, rotavirus commonly causes elevation of liver transaminases.