Clinical range of neonatal rotavirus gastroenteritis

Identification of Rotavirus Strains Causing Diarrhoea in Children under Five Years of Age in Yogyakarta, Indonesia

BACKGROUND

Rotavirus is an important cause of severe diarrhoea in children. The aims of this study were to identify the rotavirus strains that cause diarrhoea in children in Yogyakarta and to determine the association between rotavirus positivity and its clinical manifestations.

METHODS

Clinical data and stool samples were collected from children hospitalised at Kodya Yogyakarta Hospital, Indonesia. Rotavirus was detected in stool samples using an enzyme immunoassay (EIA), which was followed by genotyping using reverse transcriptase polymerase chain reaction (RT-PCR). Electropherotyping was performed for the rotavirus-positive samples.

RESULTS

In total, 104 cases were included in the study, 57 (54.8%) of which were rotavirus-positive. Based on a multiple logistic regression analysis, age group, vomiting and stool mucous were associated with rotavirus positivity. Most of the 56 samples subjected to genotyping were classified as G1 (80.36%) and P[8] (69.64%) genotypes. The genotype combination G1P[8] was identified as the most prevalent strain (66.07%). Of the 19 samples subjected to electropherotyping, 17 G1 isolates and 1 G3 isolate had long patterns, and 1 G1 isolate had a short pattern.

CONCLUSION

G1P[8] was the most dominant strain of rotavirus causing diarrhoea in children in Yogyakarta. Age group, vomiting and stool mucous were associated with rotavirus positivity.

Rotavirus Gastroenteritis in a Neonatal Unit of a Greek Tertiary Hospital: Clinical Characteristics and Genotypes

INTRODUCTION

Rotavirus (RV) infection in neonatal age can be mild or even asymptomatic. Several studies have reported that RV is responsible for 31%-87% of pediatric nosocomial diarrhea and causes gastroenteritis outbreaks in pediatric and neonatal units.

OBJECTIVES

Study clinical characteristics, genotypes and risk factors of RV infection in neonatal age.

METHODS

A prospective study was conducted from April 2009 till April 2013 in the neonatal special care unit of the largest tertiary pediatric hospital of Greece. Fecal samples and epidemiological data were collected from each neonate with gastrointestinal symptoms. RV antigen was detected with a rapid immunochromatography test. RV positive samples were further genotyped with RT PCR and sequencing using specific VP7 and VP4 primers.

RESULTS

Positive for RV were 126/415 samples (30.4%). Mean age of onset was 18 days. Seventy four cases (58%) were hospital acquired. Seasonality of RV infection did not differ significantly throughout the year with the exception of 4 outbreaks. Genotypes found during the study period were G4P[8] (58.7%), G1P[8] (14.7%), G12P[8] (9.3%), G3P[8] (9.3%), G12P[6] (5.3%), G9P[8] (1.3%) and G2P[4] (1.3%). RV cases presented with: diarrhea (81%), vomiting (26.2%), fever (34.9%), dehydration (28.6%), feeding intolerance (39.7%), weight loss (54%), whilst 19% of cases were asymptomatic. Comparing community with hospital acquired cases differences in clinical manifestations were found.

CONCLUSIONS

Significant incidence of nosocomially transmitted RV infection in neonatal age including asymptomatic illness exists. Genotypes causing nosocomial outbreaks are not different from community strains. Circulating vaccines can be effective in prevention of nosocomial RV infection through herd immunity.

Clinical characteristics and genotypes of rotaviruses in a neonatal intensive care unit

BACKGROUND

There are few reports on the symptoms of rotavirus infections in neonates. This study aims to describe clinical signs of rotavirus infections among neonates, with a particular focus on preterm infants, and to show the distribution of genotypes in a neonatal intensive care unit (NICU).

METHODS

A prospective observational study was conducted at a regional NICU for 1 year. Stool specimens from every infant in the NICU were collected on admission, at weekly intervals, and from infants showing symptoms. Rotavirus antigens were detected by enzyme-linked immunosorbent assay (ELISA), and genotypes were confirmed by Reverse transcription-Polymerase chain reaction (RT-PCR). The infants were divided into three groups: symptomatic preterm infants with and without rotavirus-positive stools [Preterm(rota+) and Preterm(rota-), respectively] and symptomatic full- or near-term infants with rotavirus-positive stools [FT/NT(rota+)]. Demographic and outcome data were compared among these groups.

RESULTS

A total of 702 infants were evaluated for rotaviruses and 131 infants were included in this study. The prevalence of rotavirus infections was 25.2%. Preterm(rota+) differed from Preterm(rota-) and FT/NT(rota+) with respect to frequent feeding difficulty (p = 0.047 and 0.034, respectively) and higher percentage of neutropenia (p = 0.008 and 0.011, respectively). G4P[6] was the exclusive strain in both the Preterm(rota+) (97.7%) and FT/NT(rota+) (90.2%), and it was the same for nosocomial, institutional infections, and infections acquired at home.

CONCLUSION

Systemic illness signs such as feeding difficulty and neutropenia are specific for preterm infants with rotavirus infections. G4P[6] was exclusive, regardless of preterm birth or locations of infections. This study might be helpful in developing policies for management and prevention of rotavirus infections in NICUs.

Clinical manifestations of a cluster of rotavirus infection in young infants hospitalized in neonatal care units

PURPOSE

To define the clinical manifestations of rotavirus (RV) infection in neonates and young infants hospitalized in neonatal care units, which are rarely reported.

MATERIALS AND METHODS

From October 2008 to September 2010, a total of 153 stool specimens positive for RV were detected from 100 neonates and young infants hospitalized in neonatal care units of our hospital. Four infants had two episodes of RV infection. Demographics and clinical presentations of these infants were collected and analyzed. The infants were further classified as having hospital-acquired (HA) or community-acquired (CA) RV infection.

RESULTS

Of the 104 episodes from 100 patients, 76 (73%) were classified as HA. Fifty-six infants were male. The mean age of onset was 2 days. The most common presentations were loose stool passages (52.9%), abdominal distension (51.9%), blood or mucus in stool (42.3%), and unstable vital signs (32.7%). Watery character in stool passage was identified in 13.5% of the infants and vomiting in 21.2%. A picture suggestive of necrotizing enterocolitis (NEC) was identified in 22 episodes (21.1%), and 12 of these were stage II or above. The average number of hospitalization days from the onset of HA-RV infection was 23 days. Compared with those in the CA group, the infants in the HA group had a significantly higher rate of blood or mucus in stools (52.6% vs. 14.3%, p < 0.01) and unstable vital signs (39.5% vs. 14.3%, p = 0.02), but a lower rate of watery diarrhea (9.2% vs. 28.6%, p = 0.04) and fever (13.8% vs. 42.9%, p < 0.01). Overall, there were five deaths, but all of these infants had major diseases.

CONCLUSION

Bloody, mucoid stools and unstable vital signs, instead of fever with watery diarrhea, are commonly seen in neonates and young infants with RV infection. A substantial proportion of these infants may present as NEC. Once introduced, RV appears to become a troublesome problem of HA infections in neonatal care settings.

Oral immunoglobulin for the prevention of rotavirus infection in low birth weight infants

BACKGROUND

Rotavirus is a common neonatal nosocomial viral infection and epidemics with the newer P(6)G9 strains have been reported. Local mucosal immunity in the intestine to rotavirus is important in the resolution of infection and protection against subsequent infections. Oral administration of anti-rotaviral immunoglobulin preparations might be a useful strategy in preventing rotaviral infections, especially in low birth weight babies.

OBJECTIVES

To determine the effectiveness and safety of oral immunoglobulin preparations for the prevention of rotavirus infection in hospitalized low birthweight infants (birthweight < 2500 g)

SEARCH METHODS

The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE, EMBASE, CINAHL, biological Abstracts (BIOSIS), Science Citation Index for articles citing Barnes 1982 and the proceedings of the Pediatric Academic Societies from 1991 onwards were searched in July 2011. Ongoing trials were also searched at clinicaltrials.gov and controlled-trials.com

SELECTION CRITERIA

The criteria used to select studies for inclusion were: 1) design: randomized or quasi-randomized controlled trials; 2) participants: hospitalized low birthweight infants; 3) intervention: oral immunoglobulin preparations for prevention of rotavirus infection compared to placebo OR no intervention; 4) at least one of the following outcomes were reported: all cause mortality during hospital stay, mortality due to rotavirus infection during hospital stay, rotavirus infection , duration of diarrhea, need for rehydration, duration of viral excretion, duration of infection control measures, length of hospital stay in days, recurrent diarrhea or chronic diarrhea.

DATA COLLECTION AND ANALYSIS

The two review authors independently abstracted data from the included trials.

MAIN RESULTS

One published study (Barnes 1982) was eligible for inclusion in this review. Barnes 1982 found no significant difference in the rates of rotavirus infection after oral gammaglobulin versus placebo in hospitalized low birthweight babies [RR 1.27 (95% CI 0.65 to 2.37)]. In the subset of infants who became infected with rotavirus after receiving gammaglobulin or placebo for prevention of rotavirus infection, there was no significant difference in the duration of rotavirus excretion between the group who had gammaglobulin (mean 2 days, range 1 to 4 days) and the group who had placebo (mean 3 days, range 1 to 6 days). Barnes 1982 reported no adverse effects after administration of oral immunoglobulin preparations.

AUTHORS' CONCLUSIONS

Current evidence does not support the use of oral immunoglobulin preparations to prevent rotavirus infection in low birthweight infants. Researchers are encouraged to conduct well-designed neonatal trials using the newer preparations of anti-rotaviral immunoglobulins (colostrum, egg yolk immunoglobulins) and include cost effectiveness evaluations.

Oral immunoglobulin for the treatment of rotavirus diarrhea in low birth weight infants

BACKGROUND

Rotavirus infection is the most common neonatal nosocomial viral infection. It is a major health problem worldwide. Epidemics with the newer P(6)G9 strains have been reported in neonatal units globally. These strains can cause severe symptoms in most infected infants. Infection control measures become necessary and the utilization of hospital resources increase. Local mucosal immunity in the intestine to rotavirus is important in the resolution of infection and protection against subsequent infections. Boosting local immunity by oral administration of anti-rotaviral immunoglobulin preparations might be a useful strategy in treating rotaviral infections, especially in low birth weight babies.

OBJECTIVES

To determine the effectiveness and safety of oral immunoglobulin preparations for the treatment of rotavirus diarrhea in hospitalized low birth weight infants (birth weight less than 2500 g)

SEARCH STRATEGY

Electronic databases including The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3, 2004), MEDLINE, EMBASE and CINAHL, Biological Abstracts (BIOSIS) were searched by the strategy outlined in the protocol. Science Citation Index search for all articles that referenced Barnes 1982 were searched. The proceedings of the Pediatric Academic Societies published online at 'Abstracts Online' were searched. Ongoing registered trials at www.clinicaltrials.gov and www.controlled-trials.com were searched. Authors prominent in the field were contacted for any unpublished articles and more information on published articles was sought. Reference lists of identified clinical trials and personal files were also reviewed. The above search was updated in July 2011.

SELECTION CRITERIA

The criteria used to select studies for inclusion were: 1) DESIGN: randomized or quasi-randomized controlled trials 2) Hospitalized low birth weight infants with rotavirus diarrhea 3) INTERVENTION: Oral immunoglobulin preparations compared to placebo or no intervention 4) At least one of the following outcomes were reported: All cause mortality during hospital stay, mortality due to rotavirus infection during hospital stay, duration of diarrhea, need for rehydration, duration of viral excretion, duration of infection control measures, length of hospital stay in days, recurrent diarrhea or chronic diarrhea

DATA COLLECTION AND ANALYSIS

The two reviewers were to independently abstract data from eligible trials. No data were available for analysis.

MAIN RESULTS

No eligible randomized controlled trials were found.

AUTHORS' CONCLUSIONS

No randomized controlled trials that assessed the effectiveness or safety of oral immunoglobulin preparations for the treatment of rotavirus diarrhea in hospitalized low birth weight infants were found. Clinical trials that address the issue of oral immunoglobulin treatment of rotavirus infection are needed.

Comparison of viral load and duration of virus shedding in symptomatic and asymptomatic neonatal rotavirus infections

A single rotavirus strain causing asymptomatic infections as well as severe gastrointestinal disease has been described in the neonatal nurseries of the Christian Medical College, Vellore. In this study, quantitative real-time RT-PCR was used to determine the association of viral load with the presence of gastrointestinal symptoms in neonates. Viral load was estimated in terms of the crossing point [C(t) value] at which the amplicon could be detected in the real-time PCR assay. The study was carried out on 103 neonates, including 33 asymptomatic neonates and 70 neonates with different gastrointestinal symptoms. The duration of virus shedding was also compared between five symptomatic and four asymptomatic neonates using real-time RT-PCR. There was no significant difference in viral load between symptomatic and asymptomatic neonates (P = 0.087). Among neonates with different gastrointestinal symptoms, those presenting with feed intolerance and abdominal distension had a significantly higher viral load than those with other gastrointestinal symptoms (P = 0.02). For the study on virus shedding, nine neonates were followed up for a median duration of 53 days, with a median of 31 samples tested per child. Extended shedding of low copies of rotavirus was found, with no significant differences in pattern of shedding between symptomatic and asymptomatic neonates. The lack of correlation between viral load and gastrointestinal disease demonstrates yet another difference between neonatal rotavirus infection and infection in older children where higher viral load correlates with severe disease.

Rotavirus infection in the neonatal nurseries of a tertiary care hospital in India

BACKGROUND

The majority of neonatal rotavirus infections are believed to be asymptomatic, and protection from subsequent infection and disease has been reported in neonatally infected children. In this study, we present the results of a 4-year prospective surveillance in the neonatal nurseries of a tertiary care hospital in south India.

METHODS

Stool samples from neonates admitted for >48 hours either with gastrointestinal (GI) symptoms or with nonenteric pathology were screened for rotavirus. Careful assessment of clinical data was carried out. G- and P-typing for all symptomatic rotavirus positive cases and equal number of asymptomatic controls from the same month was determined by reverse transcription polymerase chain reaction.

RESULTS

Rotavirus was detected in 43.9% of 1411 neonates, including those with and without gastrointestinal disease. Rotavirus detection was significantly higher among neonates with GI disease (55.5%) than asymptomatic neonates (44.4%) (P < 0.001). Rotavirus was seen in association with diarrhea, vomiting, feed intolerance, necrotizing enterocolitis, hematochezia, gastroesophageal reflux, and abdominal distension. Diarrhea was significantly more frequent in neonates with rotavirus infection (P < 0.001) whereas uninfected neonates developed significantly more feeding intolerance (P < 0.001). Significantly greater proportion of term neonates with GI disease were positive for rotavirus than preterm neonates (P < 0.001). G10P[11] was the most common genotype associated with both symptomatic and asymptomatic infections.

CONCLUSIONS

This study documents the high rates of rotavirus infection in the neonatal nurseries and the continuing detection of the G10P[11] strain associated with GI disease in Vellore.

Emerging trends in acquired neonatal intestinal disease: is it time to abandon Bell's criteria?

In the last decade, it has become increasingly clear that necrotizing enterocolitis (NEC) is neither a uniform nor a well-defined disease entity. There are many factors that are forcing this unwelcome realization upon the neonatal and pediatric surgery communities. In the course of this manuscript we will review the history and the physical findings of the disparate etiologies of acquired neonatal intestinal diseases (ANIDs), some which do lead to the common final pathology of NEC and some which do not. New guidelines for distinguishing between ANIDs will also be suggested.

Rotavirus-associated necrotizing enterocolitis: an insight into a potentially preventable disease?

PURPOSE

The aim of this study was to test the hypothesis that rotavirus-associated necrotizing enterocolitis (NEC + RV) differs from NEC associated with other organisms (NEC-RV).

METHODS

Neonates with modified Bell stage II or higher NEC were identified. Demographic, clinical, and outcome information was collected prospectively. Fecal specimens from all infants were tested for confirmation of rotavirus infection (RVI) by immunoelectron microscopy (IEM).

RESULTS

Of 2,444 admissions in the neonatal intensive care unit (NICU), 129 (5.3%) had NEC. Thirty-eight (29%) were rotavirus positive. The 2 groups did not differ in maternal or neonatal characteristics. Stage III or higher NEC was more common in the NEC-RV infants (62% v. 39%; P =.032), whereas recurrence was more common in NEC + RV group (P <.0001). The predominant distribution of nondiffuse pneumatosis (n = 52) was right sided in NEC-RV group and left sided in NEC + RV group (P <.0001). Surgical intervention (SI) did not differ between the 2 groups. The complications and mortality rates also were similar. Severe pneumatosis (P =.009) and severe thrombocytopenia (Platelet count < 50,000/mm3; P <.0001) increased, while human milk feedings decreased (P =.022) the odds for surgery. The annual distribution of NEC + RV paralleled RVI in the community.

CONCLUSIONS

Generally, NEC + RV is a less severe disease than NEC - RV as classified by modified Bell staging. However, it can reach advanced stages obscuring distinction from NEC - RV. Indications for surgery should not be altered by identification of RVI in these infants. Monitoring RVI in the community, adhering to infection control measures, human milk feedings, and improving neonatal immunity against RVI may reduce the incidence of NEC + RV.

Oral immunoglobulin for the prevention of rotavirus infection in low birth weight infants

BACKGROUND

Rotavirus infection is the most common neonatal nosocomial viral infection. Epidemics with the newer P(6)G9 strains have been reported in neonatal units worldwide. These strains can cause severe symptoms in infected infants. Infection control measures become necessary and the utilisation of hospital resources increase. Local mucosal immunity in the intestine to rotavirus is important in the resolution of infection and protection against subsequent infections. Boosting local immunity by oral administration of anti-rotaviral immunoglobulin preparations might be a useful strategy in preventing rotaviral infections, especially in low birth weight babies.

OBJECTIVES

To determine the effectiveness and safety of oral immunoglobulin preparations for the prevention of rotavirus infection in hospitalised low birthweight infants (birth weight less than 2500 gms)

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 2, 2002), MEDLINE, EMBASE and CINAHL were searched. Science Citation Index was searched for all articles which referenced Barnes 1982. The proceedings of the Pediatric Academic Societies which were published in the journal, Pediatric Research from 1991 onwards were searched as well as abstracts of doctoral dissertations and theses from 1960 onwards. The above mentioned search strategy was completed in June 2002. Authors prominent in the field were contacted for any unpublished articles and more information on published articles was sought. Reference lists of identified clinical trials and personal files were reviewed.

SELECTION CRITERIA

The criteria used to select studies for inclusion were: 1) DESIGN: randomised or quasi-randomised controlled trials. 2) PARTICIPANTS: Hospitalised low birthweight infants. 3) INTERVENTION: Oral immunoglobulin preparations for prevention of rotavirus infection compared to placebo OR no intervention. 4) At least one of the following outcomes were reported: All cause mortality during hospital stay, mortality due to rotavirus infection during hospital stay, rotavirus infection, duration of diarrhoea, need for rehydration, duration of viral excretion, duration of infection control measures, length of hospital stay in days, recurrent diarrhoea or chronic diarrhoea.

DATA COLLECTION AND ANALYSIS

The two reviewers independently abstracted data from the included trials

MAIN RESULTS

One published study (Barnes 1982) was eligible for inclusion in this review. Two additional studies are awaiting assessment re eligibility for inclusion. Barnes 1982 found no significant difference in the rates of rotavirus infection after oral gammaglobulin versus placebo in hospitalised low birthweight babies [RR 1.27 (95% CI 0.65-2.37)]. In the subset of infants who became infected with rotavirus after receiving gammaglobulin or placebo for prevention of rotavirus infection, there was no significant difference in the duration of rotavirus excretion between the group who had gammaglobulin (mean 2 days, range 1-4 days) and the group who had placebo (mean 3 days, range 1-6 days). No adverse effects were reported by Barnes 1982 after administration of oral immunoglobulin preparations.

REVIEWER'S CONCLUSIONS

Current evidence from one randomised controlled trial does not support the routine use of oral immunoglobulin preparations for the prevention of rotavirus infection in low birth-weight infants. However, newer immunoglobulin preparations which have been found to be effective in older children have not been tested in neonatal trials. Therefore, researchers should be encouraged to conduct well designed trials in neonates at risk for rotavirus infections using the newer preparations of anti-rotaviral immunoglobulins (colostrum, egg yolk immunoglobulins). Such trials should also include cost effectiveness evaluations.

Oral immunoglobulin for the treatment of rotavirus infection in low birth weight infants

BACKGROUND

Rotavirus infection is the most common neonatal nosocomial viral infection. Epidemics with the newer P(6)G9 strains have been reported in neonatal units worldwide. These strains can cause severe symptoms in most infected infants. Infection control measures become necessary and the utilisation of hospital resources increase. Local mucosal immunity in the intestine to rotavirus is important in the resolution of infection and protection against subsequent infections. Boosting local immunity by oral administration of anti-rotaviral immunoglobulin preparations might be a useful strategy in treating rotaviral infections, especially in low birth weight babies.

OBJECTIVES

To determine the effectiveness and safety of oral immunoglobulin preparations for the treatment of rotavirus infection in hospitalised low birthweight infants (birth weight less than 2500 gms)

SEARCH STRATEGY

Electronic databases including The Cochrane Controlled Trials Register (The Cochrane Llibrary, Issue 2, 2002), MEDLINE (1966 - June 2002), EMBASE (1980 - June 2002) and CINAHL (1982 - June 2002) were searched by the strategy outlined in the protocol. Science Citation Index search for all articles which referenced Barnes 1982 were searched. The proceedings of the Pediatric Academic Societies which were published in the journal, Pediatric Research, from 1991 were searched as well as abstracts of the doctoral dissertations and theses from 1960. All of the above search strategies were completed in June 2002. Authors prominent in the field were contacted for any unpublished articles and more information on published articles was sought. Reference lists of identified clinical trials and personal files were also reviewed.

SELECTION CRITERIA

The criteria used to select studies for inclusion were: 1) DESIGN: randomised or quasi-randomised controlled trials 2) Hospitalised low birthweight infants with rotavirus infection 3) INTERVENTION: Oral immunoglobulin preparations compared to placebo OR no intervention 4) At least one of the following outcomes were reported: All cause mortality during hospital stay, mortality due to rotavirus infection during hospital stay, duration of diarrhoea, need for rehydration, duration of viral excretion, duration of infection control measures, length of hospital stay in days, recurrent diarrhoea or chronic diarrhoea

DATA COLLECTION AND ANALYSIS

The two reviewers were to independently abstract data from eligible trials. No data analysis was possible at this point.

MAIN RESULTS

No eligible randomised controlled trials were found.

REVIEWER'S CONCLUSIONS

We found no randomised controlled trials which assessed the effectiveness or safety of oral immunoglobulin preparations for the treatment of rotavirus infections in hospitalised low birthweight infants.

Clinical manifestations of rotavirus infection in the neonatal intensive care unit

OBJECTIVES

This report describes clinical signs of rotavirus infection (RVI) among neonates admitted to a neonatal intensive care unit (NICU), compares these signs between term and preterm neonates and assesses the seasonal distribution of RVI in the NICU with that of the community.

METHODS

After an initial prevalence study of 28 days, a prospective longitudinal study in the NICU was conducted. During the next 48 months from December 1, 1991 to November 30, 1995, term and preterm NICU patients were evaluated daily for pre-defined deviations in their baseline gastrointestinal status. Fecal specimens of neonates who fulfilled the entry criteria were tested for rotavirus by a monoclonal antibody-based enzyme immunoassay and by immunoelectron microscopy. Demographic and outcome data for these neonates were collected. In addition data assessing RVI in the community were collected during this period.

RESULTS

The prevalence of RVI among NICU patients was 18.4%. Of 194 neonates included in the longitudinal study, 95 had RVI. Neonates with RVI differed from those without RVI with respect to frequent stooling (P = 0.0005), higher percentage of bloody mucoid stools (P = 0.003) and higher percentage of watery stools (P = 0.023). The odds of these three clinical outcomes were approximately 2.5 times higher in neonates with RVI than in neonates without RVI. Among neonates included in the study advanced necrotizing enterocolitis occurred at the same rate (15%) among those with and without RVI. Comparisons between term and preterm neonates with RVI showed that frequent stooling (P = 0.003) and watery stools (P = 0.0001) occurred more often among term neonates, whereas bloody mucoid stools (P = 0.001), abdominal distention (P = 0.03) and intestinal dilatation (P = 0.016) were more common in preterm neonates. The seasonal distribution of RVI in NICU paralleled its distribution in the community.

CONCLUSION

RVI appears prevalent in the NICU setting. An absence of watery stools in a neonate should not preclude consideration of RVI when evaluating gastrointestinal signs among neonates. The clinical spectrum of RVI differs in term and preterm infants.

Neonatal rotavirus infection in Belém, northern Brazil: nosocomial transmission of a P[6] G2 strain

A total of 614 fecal specimens were obtained during a survey for rotavirus infection conducted between May 1996 and May 1998 among 437 newborns admitted to special care nurseries at a public hospital in the urban area of Belém, Brazil. Routine stool samples were taken weekly from all babies up to the age of 28 days. Overall, 51 (11.7%) of the neonates excreted rotaviruses while in hospital, of whom 42 (82.3%) developed asymptomatic nosocomial infection; nosocomial infection was also proved in five of the nine patients with diarrhea. Three distinct RNA profiles were detected, of which one short electropherotyping pattern was far more frequent ( approximately 90% of the strains). Using monoclonal antibody-based enzyme immunoassays, 32 (62.7%) of the rotavirus-positive strains were classified as G2, and 1 (1.9%) as mixed G1 and G2. A G serotype could not be assigned to 18 (35.3%) of the isolates. A reverse transcription-polymerase chain reaction was used for determining the VP4 type-specificity of a subset of 28 rotavirus-positive samples. Characterization of the VP7-genotype specificity was also sought for 18 of these latter strains. Overall, P[6] and G2 genotypes were identified in 93% and 94% of tested samples respectively, with results being further confirmed by Southern hybridization. Although surveillance was conducted during a 25-month period, 50 (98%) of 51 rotavirus isolates clustered between January and December 1997. The earliest [P6]G2 rotavirus infections were detected by late January 1997, involving two (13- and 14-day-old) babies admitted with acute diarrhea. Thereafter, strains bearing these genotype specificities were identified among five infants with hospital-acquired gastroenteritis, followed by 16 others who were infected asymptomatically. This is the first report from Brazil describing nosocomial transmission of P[6]G2 rotavirus strains among neonates.

South African G4P[6] asymptomatic and symptomatic neonatal rotavirus strains differ in their NSP4, VP8*, and VP7 genes

Over the past decade, a G4P[6] strain has been found to be circulating in different neonatal wards in the Pretoria area. This endemic strain was associated with both asymptomatic and symptomatic infection, providing the opportunity to undertake a molecular study of some of the putative "virulence" genes. The genes encoding NSP4, VP8*, and VP7 of two asymptomatic and two Symptomatic strains were sequenced and compared with ST3. Within each of these genes, amino acid substitutions unique to South African strains were recorded. Four conserved amino acid differences between asymptomatic and symptomatic strains at aa 82 (serine to leucine), aa 114 (aspartic acid to glutamic acid), aa 138 (proline to threonine), and aa 169 (leucine to serine) were identified within the NSP4 gene. The hypervariable region of VP8* exhibited 10 specific amino acid differences (at aa 73, 78, 98, 111, 116, 142, 145, 167, 169, and 188) between asymptomatic and symptomatic strains, while three amino acid substitutions within VP7 were noted. These changes to VP7 occurred within the glycosylation site at aa 70 (leucine to serine), at antigenic region A (aa 96, asparagine to threonine), and at aa 318 (aspartic acid to glycine). It may be speculated that these changes are specific to G4P[6] strains. Furthermore, the observed substitutions may also be particular to South African strains. NSP4, VP8*, and VP7 have been associated with virulence and the amino acid substitutions within these genes correlate with both asymptomatic and symptomatic infection observed in neonates.

Enteric infectious disease in neonates. Epidemiology, pathogenesis, and a practical approach to evaluation and therapy

There are many bacterial and viral pathogens that have been associated with enteric disease during the newborn period. These pathogens have widely different mechanisms of action on the intestinal epithelium and are associated with a spectrum of clinical findings. Infected infants can be asymptomatic, have gastroenteritis, or have a fulminant sepsis picture. To determine therapy and institute appropriate infection control measures requires the ability to recognize the clinical syndrome and correctly interpret laboratory results. All of these principles can be applied to the premature infant in the neonatal intensive care nursery as well as the full-term infant at home.

Enteric infectious disease in neonates. Epidemiology, pathogenesis, and a practical approach to evaluation and therapy

There are many bacterial and viral pathogens that have been associated with enteric disease during the newborn period. These pathogens have widely different mechanisms of action on the intestinal epithelium and are associated with a spectrum of clinical findings. Infected infants can be asymptomatic, have gastroenteritis, or have a fulminant sepsis picture. To determine therapy and institute appropriate infection control measures requires the ability to recognize the clinical syndrome and correctly interpret laboratory results. All of these principles can be applied to the premature infant in the neonatal intensive care nursery as well as the full-term infant at home.

Further characterisation of human rotaviruses isolated from asymptomatically infected neonates in South Africa

Stool specimens were collected from healthy neonates at Ga-Rankuwa Hospital in the winters of 1984 and 1986 and tested for the presence of rotavirus infection. Asymptomatic excretion was found to occur in 25% of the newborn babies analysed. Gel electrophoresis of the rotavirus RNA genome revealed that a genomically stable strain of rotavirus was endemic in the ward at the time intervals examined. Hybridisation analysis of the VP4 and VP7 rotavirus genes, which encode the outer capsid neutralization proteins of the virus, was conducted. These results showed the presence of a serotype 4 rotavirus strain with an M37-like VP4 gene allele, which remained conserved in the nursery over the time period examined. Partial nucleotide sequences were obtained for a variable region of the VP7 gene and for the hyperdivergent region of the VP4 gene from 8 of these viruses and showed that remarkable conservation of these regions in the genes of the viruses occurred over time.

[Rotavirus neonatal diarrhea]

A retrospective survey was performed among 24 neonatal care units. In the years 1989-1990, outbreaks of rotavirus infections were observed in 58 % and recurred in 46 % of neonatal care units. Six units presented with 3 or more outbreaks. Rapid diagnosis methods always were available and were usually agglutination latex test or ELISA test. Measures were suggested to limit the spread of the outbreaks : wearing of a gown ascribed to each infant (20/0) ; isolation of infected neonates (16/3) ; cohorting infected neonates (11/7) ; systematic stool examination for rotavirus identification in all neonates (9/10) ; use of gloves for handling contaminated stools (6/13). Stopping admissions and systematic stools examination in staff members were never applied.

Nosocomial outbreak of neonatal gastroenteritis caused by a new serotype 4, subtype 4B human rotavirus

A nosocomial outbreak of rotavirus gastroenteritis involving 52 newborns occurred between June and September 1988 at the University Children's Hospital of Freiburg, Federal Republic of Germany. Stools from 27 representative patients were examined for rotavirus serotypes, using a monoclonal antibody-based enzyme-linked immunosorbent assay. The electropherotype was also examined by polyacrylamide gel electrophoresis of genomic RNA. As many as 18 patients were found to be infected by serotype 4, subtype 4B strain, and in all of them the same electropherotype was detected. Although rotavirus from the remaining nine patients could not be typed, the electropherotype in four was identical to that of the serotype 4, subtype 4B strain. Thus, most of the patients in the outbreak were infected by the same rotavirus strain. Retrospective epidemiological studies showed that the 4B strain began to circulate at the hospital in January 1988, whereas only rotavirus serotypes 1, 3, and 4A were detected in 1985-1987. The primary case of the outbreak was presumably a newborn with acute gastroenteritis, admitted to the hospital from a small maternity unit in the same urban area. During the outbreak, 12 of 44 healthy newborns in the nurseries of the Children's Hospital and other maternity hospitals were found to be asymptomatic rotavirus carriers, and in three of the newborns the same 4B strain was detected. This is the first reported outbreak caused by a serotype 4, subtype 4B strain.

Incidence of Clostridium difficile in hospitalized children. A prospective study

A total of 394 children, aged 0-14 years, referred to a paediatric department were investigated for the occurrence of Clostridium difficile, its cytotoxin in faeces, and its clinical significance in a prospective study over one year. Of the children in the investigation, 337 suffered from gastrointestinal diseases or had been treated with antibiotics prior to the investigation. Twenty-four percent of these children had Cl. difficile in one or more faecal samples and toxin was demonstrated in half of these patients. In 18/148 (12%) of the patients with acute gastroenteritis Cl. difficile was isolated as the only pathogen. In contrast, among 57 control children with no gastrointestinal symptoms and no prior antibiotic treatment significantly fewer harboured Cl. difficile (p less than 0.01). Cl. difficile was isolated with similar frequency in children with or without prior antibiotic treatment. Isolation of Cl. difficile was significantly higher in patients under one year of age (p less than 0.001). In 78% of the patients with Cl. difficile the bacteria were found in faeces during the initial two days of hospitalization indicating that most of the cases were community acquired. The occurrence of Cl. difficile was not influenced by seasonal variation and the distribution between sexes was equal.

Circulating and breast-milk anti-rotaviral antibodies and neonatal rotavirus infections: a maternal-neonatal study

In view of the high prevalence of rotavirus (RV) diarrhoea in Indian (Asian) infants in South Africa, a hospital-based study of 124 mothers and their neonates was carried out to establish the prevalence of maternal and neonatal circulating anti-RV antibodies, RV antibodies in breast-milk, and neonatal RV infections in this population. Thirty-four per cent of the mothers and 38% of the neonates had complement-fixing (CF) serum antibodies. There was a significant correlation between maternal and cord blood antibody levels (p less than 0.001; chi-square test). Fifteen per cent of hospital-born newborns showed asymptomatic RV excretion while still in hospital, mostly at 2-6 days of age, but some even earlier, with two shedding the virus before the age of 24 h. This excretion occurred in both seronegative and seropositive babies. The breast-milk of only 3.2% of the mothers was positive for CF-anti-RV antibodies, implying that either these were not present in the breast-milk or that the CF-test employed was not sufficiently sensitive for detecting these antibodies in milk specimens. Eighteen (18.2%) of 99 infants followed up showed evidence of RV infection 1-7 months after birth; none was symptomatic; 12 excreted RV in the stools while 6 others seroconverted. Asymptomatic reinfection was documented in 4 of 14 babies who had been infected initially as neonates.

Neonatal rotavirus infection and its relation to cord blood antibodies

Among 274 neonates born at the maternity services of an urban hospital in India, 36.1% of the infants shed rotavirus in feces (as detected by ELISA) by 72 h of life. The excretion rate increased to 70.3% among the 120 infants who stayed for 5 days or more at the hospital. Diarrhoeal symptoms of mild and self-limited nature were observed only in 19.2% of the rotavirus excretors, the remaining being asymptomatic. Among the 98 infants who received supplement feeds, 49% acquired rotavirus infection as against 24.7% of the 150 exclusively breast fed infants (p less than 0.001). Viral RNA in the feces of all rota positive infants showed the same electropherotype, indicating infection from a common source. The mean percentage rotavirus inhibitory activity of cord sera in the infected and non-infected infants was 50.2 +/- 21.7 and 56.6 +/- 19.2 respectively (p greater than 0.05), suggesting that cord blood antibodies do not offer significant protection against neonatal rotavirus infection.

Neonatal rotavirus-associated necrotizing enterocolitis: case control study and prospective surveillance during an outbreak

After the death of a premature infant from rotavirus-associated necrotizing enterocolitis, we instituted prospective surveillance for this disease in our neonatal intensive care unit. During the 4-month study period an additional six cases of necrotizing enterocolitis and eight cases of hemorrhagic gastroenteritis occurred. Rotavirus infection was documented in 11 of these 15 symptomatic infants, in comparison with only eight rotavirus infections in 147 asymptomatic or minimally symptomatic babies (P less than 0.0001). Stools from 110 nursery personnel tested during the outbreak did not contain rotavirus. However, 12 of 59 staff members had serum IgM antibody against rotavirus, suggesting recent infection. In a case-control study we compared babies with severe gastrointestinal illness with a control group randomly selected from asymptomatic babies in the nursery during the time of the outbreak. Univariate analysis found six categorical variables and nine continuous variables that were significantly associated with disease. Multivariate logistic regression analysis, however, found only birth weight (P less than 0.0001), rotavirus infection (P less than 0.0001), and age at time of first nonwater feeding (P less than 0.02) to be associated with gastrointestinal illness. This study provides further evidence for the role of infection in some cases of neonatal necrotizing enterocolitis and hemorrhagic gastroenteritis.

Cultivation and characterization of rotavirus strains infecting newborn babies in Melbourne, Australia, from 1975 to 1979

Twenty-three rotavirus strains obtained from the stools of 71 newborn babies were adapted to growth in MA-104 cells. Babies were housed in newborn nurseries of eight different obstetric hospitals in Melbourne between 1975 and 1979. All strains belonged to serotype 3 when reacted with serotype-specific neutralizing monoclonal antibodies in an enzyme immunoassay. Genome RNA of these 23 strains and of one stool virus not adapted to cell culture were compared by coelectrophoresis of mixtures of RNA. When strains were compared by coelectrophoresis of RNA for 4 h at 40 mA current, the majority appeared to be identical. Coelectrophoresis at 4 degrees C for 17 h at 10 mA current with 0.75-mm-thick polyacrylamide gels resulted in increased resolution of segments, revealing more genetic diversity than previously observed. Seventeen different electropherotypes showing slight variations in migration of one to seven segments were identified. Segments 5 and 7, 8, 9, 10, and 11 varied more frequently than segments 1, 2, 3, 4, and 6. Strains endemic in one hospital from 1975 to 1983 showed increased numbers of segmental changes over time. Differing patterns of reaction with two neutralizing monoclonal antibodies reacting with VP3 and VP7 were observed. Comparison of electropherotypes of three neonatal strains with a serotype 3 community strain showed marked differences in segment migration. The serotypic similarity, electropherotypic dissimilarity from community strains, and asymptomatic nature of most infections are additional evidence that these viruses infecting newborn babies form a unique group of rotaviruses.

A prospective study of rotavirus infections in neonatal and maternity wards

The occurrence and symptomatology of rotavirus infections was studied at three maternity wards and one neonatal unit. Rotavirus was identified in 12.7% of 553 infants and 1.3% of 542 mothers at the maternity wards. Infections were more frequent in a mixed obstetric/gynecology ward than in the pure obstetric wards. Only 10% of the infants had symptomatic infections. Subgroups of rotavirus was determined in 41 infants: 22 of subgroup I and 19 of subgroup II, which is the subgroup accounting for the majority of childhood gastroenteritis. Rotavirus was found in faecal samples from 37% of the infants at the neonatal unit during an eight-month survey. A seasonal variation with most infections during colder months was seen. Subgroup determination was possible in 29 cases, 14 subgroup I and 15 subgroup II. Fifteen per cent of the infections demonstrated diarrheal symptoms. No significant difference among other clinical data registered was seen among rotavirus infected compared to the non-infected infants. We conclude that neonatal rotavirus infections occur as an endemic infection at our maternity wards possibly combined with infections due to external sources of virus in mixed wards and neonatal units.

Rotavirus infections in high-risk neonates

During a 12-month period, 260 neonates in a referral neonatal nursery were examined weekly for rotavirus infection. A total of 15.4 per cent were found positive during their stay in the nursery and one-quarter of these neonates had symptoms of diarrhoea. Most infected neonates excreted rotavirus in only one stool sample. No seasonal variation was found in the incidence of infections. Rotavirus infection was related to low birthweight and length of stay in the neonatal nursery. Breast-fed newborns were less often infected than formula-fed neonates although they were of comparable weight and spent longer in the unit. In neonatal intensive care units methods for the detection of rotavirus in patients with diarrhoea should be undertaken routinely.

A prospective study of chlamydial, mycoplasmal, and viral infections in a neonatal intensive care unit

In a prospective study of non-bacterial infection in a neonatal intensive care unit in north west London, Chlamydia trachomatis infection was identified in 4 of 280 babies (1.4%) and was the most common cause of neonatal ophthalmia. One of the four developed pneumonitis. Ureaplasma urealyticum was found to colonise the nasopharynx in 53 of 235 babies (22.6%), with Mycoplasma hominis present in 6 of 235 babies (2.6%). There was a statistically significant association between U urealyticum colonisation and preterm birth or prolonged rupture of membranes. Colonisation occurred more commonly in babies with apnoea. Viral infection was detected in 16 of 280 babies (5.7%). Rotavirus was identified in 5 of 170 babies (2.9%) and was associated with necrotising enterocolitis in two infants and with bloody diarrhoea in another. Respiratory syncytial virus, which was identified in 4 of 280 babies (1.4%), was not associated with lower respiratory tract infection.