Intussusception and rotavirus associated hospitalisation in New Zealand

Aims: To describe the epidemiology of intussusception and its relation to rotavirus associated hospitalisation in New Zealand. Methods: National hospital discharge data between January 1998 and June 2003 for all children younger than 3 years of age with intussusception were reviewed. Independently, children from the same age group, admitted to eight paediatric units with rotavirus gastroenteritis between May 1998 and May 2000, were identified prospectively. Epidemiological characteristics of cases with intussusception were compared with those of hospitalised rotavirus disease. Results: During the 5.5 year study period, there were 277 cases of intussusception and no deaths. Most (72%) occurred in the first year of life (age adjusted incident rate 65 per 100 000 child-years, 95% CI 56 to 74). Risk of intussusception was less in females (risk ratio 0.58; 95% CI 0.43 to 0.78) and for Maori (risk ratio 0.52; 95% CI 0.35 to 0.77) when compared with European infants. In contrast to hospitalised rotavirus cases, intussusception peaked at a younger age and lacked seasonality. Conclusions: This study provides national baseline data on intussusception for future rotavirus vaccine programmes in New Zealand. Wild-type rotaviruses do not appear to have a major role in triggering intussusception. Prospective surveillance systems, using standardised case definitions and nested case-control methodology, are needed to further our understanding of the aetiology and epidemiology of intussusception.     

Rotavirus hospitalisation in New Zealand children under 3 years of age

OBJECTIVE: To describe the epidemiology of severe rotavirus gastroenteritis and to estimate the hospitalisation rates of this illness in New Zealand children under 3 years of age. METHODS: Children under 3 years of age with acute diarrhoea admitted to 1 of 8 study hospitals between 1 May 1998 and 30 April 2000 were surveyed. Their socio-demographic, treatment and length-of-stay data were recorded and stool samples tested by a rotavirus-specific enzyme-linked immunoassay. National hospital discharge data for infectious diarrhoea (International Classification of Diseases, ninth revision, 003-009) were reviewed, allowing population-based estimates for rotavirus-related hospitalisation in New Zealand. RESULTS: Of 2019 enrolled children, 1138 (56.4%) provided stools for testing, and of these 485 (42.6%) tested rotavirus positive. Rotavirus detection varied significantly by age (26.8% for 0 to 5 months, 42.5% for 6 to 11 months and 52.1% for children aged 12 to 35 months; P < 0.001), and by season (51.2% in winter/spring vs. 24.5% in summer/autumn; P < 0.001). While those infected with rotavirus were more likely to be dehydrated (50.6% vs. 37.4%; P < 0.001), their median hospital stay was similar (1.0 vs. 2.0 days; P = 0.09) to other children with acute gastroenteritis. The estimated national hospitalisation rate for rotavirus diarrhoea in children under 3 years, standardised for age and season, was 634 (95% CI 597, 672) per 100,000. In New Zealand, rotaviruses result in 1 in 52 children being hospitalised by 3 years of age. CONCLUSIONS: Rotavirus diarrhoea is an important, potentially vaccine-preventable cause of hospitalisation in New Zealand children, especially during winter and spring seasons.     

A prospective evaluation of community acquired gastroenteritis in paediatric practices: impact and disease burden of rotavirus infection.

AIMS: To examine the disease burden and epidemiology of community acquired rotavirus gastroenteritis in Austrian children treated in a paediatric practice. METHODS: A prospective, population based, multicentre study in four paediatric practices and two children's hospitals (Innsbruck and Leoben). Children 相似文献   

A prospective evaluation of community acquired gastroenteritis in paediatric practices: impact and disease burden of rotavirus infection

AIMS—To examine the disease burden and epidemiology of community acquired rotavirus gastroenteritis in Austrian children treated in a paediatric practice.
METHODS—A prospective, population based, multicentre study in four paediatric practices and two children''s hospitals (Innsbruck and Leoben). Children ⩽ 48 months of age presenting with gastroenteritis during a six month period of rotavirus peak between December 1997and May 1998 were included. Prospective testing of stool samples for rotavirus was performed using ELISA.
RESULTS—A total of 6969 children were enrolled; 171 (2.4%) had community acquired gastroenteritis. Of 144 children who could be included in further analysis, 49 (34%; median age 16.7 months) were rotavirus positive, and 95 (66%; median age 17.0 months) were rotavirus negative. Three of the rotavirus positive children (median age 14.6 months) were hospitalised. The severity of rotavirus positive gastroenteritis was significantly higher than that of rotavirus negative gastroenteritis. The incidence of community acquired gastroenteritis was 4.67 per 100 children per year, and of rotavirus positive gastroenteritis 1.33 per 100 children per year.
CONCLUSION—Rotavirus is a relevant cause of community acquired gastroenteritis in children aged 4 years and younger treated by a paediatrician. The data can be used as a basis for developing strategies to prevent infection.

     

Lack of association between rotavirus infection and intussusception: implications for use of attenuated rotavirus vaccines

BACKGROUND: Withdrawal of the tetravalent rhesus-human rotavirus vaccine Rotashield because of its association with intussusception raised concerns about a potential link between natural rotavirus disease and intussusception. Our objective was to determine whether such an association exists. METHODS: In the Southern California Kaiser Permanente Health Care Plan, a large health maintenance organization, from October, 1992, to July, 1999, we retrospectively identified by computerized data and medical charts all children <3 years old with intussusception, and from 1997 to 1999 we independently identified by prospective clinical and laboratory evaluation children <3 years old with rotavirus diarrhea. We compared the epidemiologic characteristics of intussusception and rotavirus infection in our study population and evaluated for the presence of both diseases in individual patients. RESULTS: Using computerized data we identified 124 cases of intussusception, 101 (81%) of which were confirmed by medical chart and radiologic reviews. The incidences for infants <1 year old and for children <3 years old were 41 (95% confidence interval, 32 to 55) and 17 (95% confidence interval, 13 to 20) per 100,000 child years, respectively. Between November 1997 and July 1999, we identified 470 cases of rotavirus diarrhea and none had intussusception. Although rotavirus diarrhea had a distinct peak incidence between December and February, intussusception had no apparent seasonality. The age distributions overlapped, but intussusception occurred at an earlier age than rotavirus disease. CONCLUSIONS: We found no epidemiologic evidence for an association between intussusception and natural rotavirus infection, but our study was limited by an insufficient number of cases to definitively exclude a causal link. The dramatic winter peak of rotavirus disease had no discernable parallel in the incidence of intussusception. Our data suggest that the association between tetravalent rhesus-human rotavirus vaccine and intussusception may possibly result from the nonhuman rotavirus components of that vaccine.     

Hospital surveillance of rotavirus infection and nosocomial transmission of rotavirus disease among children in Guinea-Bissau

BACKGROUND: Vaccination against rotavirus is protective against severe disease. Surveillance of rotavirus infection in developing countries might direct vaccination policy more efficiently. METHODS: We implemented WHO's generic protocols for hospital-and community-based surveillance of rotavirus gastroenteritis. From April 2001 to May 2002, and from January 2003 to June 2003, we conducted hospital surveillance for rotavirus infection at the only pediatric ward in the capital of Guinea-Bissau. Children less than 5 years of age admitted with diarrhea or developing diarrhea during hospitalization were enrolled in the study. Rotavirus infection was detected in the feces samples using an ELISA assay. Rectal swabs were also obtained and its use was validated against stool specimen. RESULTS: During the surveillance period, 161 cases of rotavirus infection were registered. During the season, rotavirus accounted for 35% of all hospitalized diarrhea cases. The rate of nosocomial disease was 1.6 per 1000 child-days (95% confidence interval [CI] = 1.02-2.51) with high rates for children aged 12 to 23 months of age (rate: 3.09; 95% CI = 1.47-6.48). Most of the rotavirus cases (93%) were in children less than 2 years of age and only 10 children aged less than 3 months were infected. Fever (risk ratio (RR) 1.56; 95% CI = 1.16-2.10) and vomiting (RR 1.38; 95% CI = 1.11-1.73) were more common in patients with rotavirus than in patients with nonrotavirus diarrhea. The case-fatality was 8%. Results from stool samples and rectal swabs were concordant in 96% of the pairs. Rectal swabs increased the detection of rotavirus cases by 6% and deaths by 33% over stool sample results. CONCLUSION: Rotavirus infections were confined to a 4-month period each year. It is an important cause of childhood diarrhea with high case-fatality ratio in Guinea-Bissau. The use of rectal swab appeared to increase the detection rate of rotavirus infection and the case-fatality rate. The high rate of nosocomial infections in hospitalized children emphasizes the need for prevention of disease.     

Two year review of intestinal intussusception in six large public hospitals of Santiago,Chile

BACKGROUND: A need for updated information on different aspects of idiopathic intussusception resurged after the Rotashield experience. Variability of incidence rates worldwide and the possibility of a more severe outcome among infants that have intussusception at a younger age are two issues that remain unclear. We aimed to provide updated information on clinical aspects of intussusception in a large population of Chilean children <2 years of age, including a best estimate of incidence rate and a comparative analysis of the clinical evolution for children younger and older than 6 months of age. METHODS: Several sources of information were used to recollect all intussusception cases 0 to 24 months of age treated in six public pediatric hospitals of the Metropolitan area during years 2000 and 2001 and to obtain updated estimates of the population covered by these hospitals. A thorough chart review of intussusception cases was performed using a standardized case report form. RESULTS: A total of 50 and 45 intussusception cases were detected for 2000 and 2001, respectively, and estimated intussusception rates for children 0 to 24 months and for the subgroup <12 months of age were 35 and 32 per 100 000, and 55 and 47 per 100 000. The monthly distribution of intussusception cases differed for both years without an identifiable reason, and no association between intussusception and rotavirus infection was observed. No intussusception-associated death was recorded. Overall complications occurred in 21% of children, and infants younger than 6 months of age did not have more complications or a more prolonged hospital stay than older children. CONCLUSIONS: Idiopathic intussusception is not uncommon among Chilean infants with incidence rates similar to those reported in the United States. There was no clear association with preexisting rotavirus infection and occurrence of complications was not related to young age.     

Changing epidemiology of intussusception in Australia

OBJECTIVES: Oral rotavirus vaccines are expected to become available in Australia within the next 2 years. In light of evidence for an association between a rotavirus vaccine and intussusception, it is important to define the baseline epidemiology of intussusception in Australia and establish a system for intussusception surveillance in the immediate post-licensure period. This study reports on incidence and epidemiology of intussusception in Australia. METHODS: Data were obtained from the Australian Institute of Health and Welfare on all patients with a discharge diagnosis of intussusception from public and private hospitals in each state and territory of Australia from 1994 to 2000. We examined age at presentation, sex, month and year of presentation, indigenous status and clinical outcomes. The incidence of intussusception was calculated and annual trends examined. Surveillance data on rotavirus gastroenteritis hospitalizations over the same time period were also obtained to compare seasonal patterns. RESULTS: From 1994 to 2000, a 39% reduction in intussusception incidence in infants aged <1 year was observed in Australia (13.1/10,000 to 8.1/10,000; P < 0.001). The incidence of intussusception was lower in indigenous infants (3.3/10,000 <1 year) compared to non-indigenous infants (10.4/10,000 <1 year; P < 0.001). There was no association between the seasonality of rotavirus infection and intussusception. Only one of 12 deaths due to intussusception was reported in an infant <1 year. CONCLUSIONS: This study documents the epidemiology of intussusception in Australia from 1994 to 2000 and provides important baseline information for future rotavirus vaccines. A lower risk of intussusception was identified in indigenous compared to non-indigenous infants.     

A case-control study to determine risk factors for hospitalization for rotavirus gastroenteritis in U.S. children

OBJECTIVE: The objective of this case-control study nested within a surveillance study conducted at 3 hospitals (Cincinnati Children's Hospital Medical Center, Cincinnati, OH; Children's Hospital of New Orleans, New Orleans, LA; and Hasbro Children's Hospital, Providence, RI) was to identify risk factors for rotavirus gastroenteritis requiring hospitalization. PATIENTS: Cases were children < or =59 months of age who were admitted with acute gastroenteritis (AGE) and found to have rotavirus infection. Controls were selected from a birth certificate registry (Cincinnati and Providence) or a registry of patients from a large practice consortium in 11 locations (New Orleans). RESULTS: Three hundred forty-nine rotavirus-infected cases and 1242 control subjects were enrolled. Breast feeding was protective against hospitalization for rotavirus AGE for infants <6 months of age. (odds ratio [OR], 5.1; 95% confidence interval [CI], 1.2-13.2). Low-birth-weight (<2500 g) infants had increased risk for hospitalization even beyond the first few months of life (OR, 2.8; 95% CI, 1.6-5.0). Children in child care were more likely to be hospitalized for rotavirus AGE than those cared for at home, particularly those > or =24 months of age (OR, 3.0; 95% CI, 1.8-5.3). Other characteristics associated with rotavirus AGE hospitalization were children <24 months of age covered by Medicaid or without insurance (OR, 2.1; 95% CI, 1.4-3.2) and having another child in the house <24 months of age (OR, 1.6; 95% CI, 1.1-2.3). The data suggest that maternal age <25 years (OR, 1.4; 95% CI, 1.0-2.0) and a mother with less than a high school education (OR, 1.5; 95% CI, 1.0-2.3) may also increase risk of rotavirus hospitalization. CONCLUSION: There are socioeconomic and environmental factors and aspects of the child's medical and dietary history that identify children at risk for hospitalization with rotavirus AGE.     

Intussusception-associated hospitalization among Venezuelan infants during 1998 through 2001: anticipating rotavirus vaccines

BACKGROUND: The first licensed rotavirus vaccine was withdrawn from use in the United States because of a low risk of intussusception. Consequently tests of new rotavirus vaccines will require some baseline knowledge of the rates and treatment of intussusception in countries where these vaccines will be tested. Therefore the objective of this study was to assess hospitalization rates and describe the epidemiologic and clinical characteristics of intussusception in Carabobo, Venezuela. METHODS: This study reviewed hospital data and clinical records of pediatric patients with intussusception admitted to eight hospitals in Carabobo between January 1, 1998 and December 31, 2001. RESULTS: For the 4-year period the average annual hospitalization rate for intussusception among infants (<1 year old) in Carabobo was 35 per 100 000 infants per year (range, 22 to 44), and intussusception was more common among boys (58 per 100 000 infants per year) than girls (29 per 100 000 infants per year) (P = 0.006). One of 67 cases occurred in the first 3 months of life (0 to 2), 55% (37) patients were 3 to 5 months old, 31% (21) were 6 to 11 months old and 12% (8) were > or =12 months old. Surgical reduction was required in 88% (52 of 59) of infants but only 1 required bowel resection. The monthly distribution of intussusception-associated hospitalizations showed no consistent seasonal pattern with the seasonality observed for patients hospitalized with rotavirus disease. CONCLUSIONS: This study provides some data about the incidence of intussusception and its epidemiology in a developing country where current or future field trials with rotavirus vaccine will be conducted.     

Prospective study of 125 cases of Staphylococcus aureus bacteremia in children in New Zealand.

BACKGROUND: Staphylococcus aureus bacteremia is a common complication of S. aureus infection. There are few pediatric studies defining the incidence and associated morbidity and mortality of S. aureus bacteremia and no such New Zealand studies. We conducted a prospective study of S. aureus bacteremia in children in New Zealand. METHODS: From July 1, 1996 to December 31, 1998, we included all children < 16 years of age with S. aureus bacteremia in Auckland and Christchurch. Relevant information regarding patient demographics, clinical course and outcome and laboratory results was recorded. RESULTS: One hundred twenty-five cases of true S. aureus bacteremia were identified. There were 4 deaths within 30 days of the onset of bacteremia. Fourteen (11%) of the children were < 1 month of age. Maori children (relative risk, 2.0; 95% confidence interval, 1.3 to 3.2) were twice as likely and Pacific Island children (relative risk, 2.5; 95% confidence interval, 1.6 to 3.8) 2.5 times as likely as white children to acquire S. aureus bacteremia. The peak incidence of S. aureus bacteremia was observed in Pacific Island children < 1 year of age (105 cases/100,000 children/year). Twenty-seven percent of cases were related to intravenous catheters. Seventy percent of cases were community-acquired. Ninety-eight percent of non-catheter-related cases in children > 1 month of age were community-acquired. There was a low rate of methicillin resistance (6%). CONCLUSIONS: S. aureus bacteremia is largely community-acquired in children in New Zealand and is more common in Pacific Island and Maori populations. Although there is a low associated mortality, a significant number are potentially preventable cases secondary to intravenous catheters.     

Shaken baby syndrome in New Zealand, 2000-2002

Aim:   To describe the epidemiology of subdural haemorrhage (SDH) in New Zealand infants.
Methods:   Prospective enrolment of all cases of infantile SDH from 2000 to 2002. Retrospective analysis of national discharge and death data for the same period.
Results:   Seventy-seven cases of infantile SDH were identified prospectively, and a further 49 cases retrospectively. Of these 126 cases, 92 resulted from non-birth-related trauma. Forty-eight of these were attributed to abuse and 28 to accidental injury. Sixteen cases were undetermined. The 'minimum' annual incidence of inflicted infantile SDH in New Zealand is 14.7 per 100 000 (95% confidence interval(CI) 10.8–19.4), and the 'maximum' 19.6 per 100 000 (95% CI 15.1–25.0). Among Maori, the 'minimum' is 32.5 per 100 000 (95% CI 21.4–47.3), and the 'maximum' 38.5 per 100 000 (95% CI 26.3–54.4).
Conclusions:   The epidemiology of infantile subdural haemorrhage in New Zealand is similar to that described elsewhere. Non-accidental head injury is a significant child health issue in New Zealand, and the incidence is particularly high among Maori.     

Risk factors for community-acquired pneumonia in pre-school-aged children

Aim: To identify risk factors for children developing and being hospitalised with community‐acquired pneumonia. Methods: Children <5 years old residing in urban Auckland, New Zealand were enrolled from 2002 to 2004. To assess the risk of developing pneumonia, children hospitalised with pneumonia (n= 289) plus children with pneumonia discharged from the Emergency Department (n= 139) were compared with a random community sample of children without pneumonia (n= 351). To assess risk of hospitalisation, children hospitalised with pneumonia were compared with the children discharged from the Emergency Department. Adjusted odds ratio (OR) with 95% confidence intervals (CIs) were used to estimate the risk of pneumonia and hospitalisation with pneumonia. Results: After adjustment for season, age and ethnicity there was an increased risk of pneumonia associated with lower weight for height (OR 1.28, 95% CI 1.10–1.51), spending less time outside (1.96, 1.11–3.47), previous chest infections (2.31, 1.55–3.43) and mould in the child's bedroom (1.93, 1.24–3.02). There was an increased risk of pneumonia hospitalisation associated with maternal history of pneumonia (4.03, 1.25–16.18), living in a more crowded household (2.87, 1.33–6.41) and one with cigarette smokers (1.99, 1.05–3.81), and mould in the child's bedroom (2.39, 1.25–4.72). Conclusions: Lower quality living environments increase the risk of pneumonia and hospitalisation with pneumonia in New Zealand. Poorer nutritional status may also increase the risk of pneumonia. Improving housing quality, decreased cigarette smoke exposure and early childhood nutrition may reduce pneumonia disease burden in New Zealand.     

Four-country surveillance of intestinal intussusception and diarrhoea in children

Aim:   Establishment of baseline epidemiology of intussusception in developing countries has become a necessity with the possibility of reintroduction of rotavirus vaccine. The current study assessed the seasonal trend in cases admitted with intussusceptions and dehydrating acute watery diarrhoea in children aged 2 months to 10 years.
Methods:   In a prospective surveillance study, teaching and research hospital sites in India (Lucknow and Nagpur), Brazil (Fortazela), Egypt (Ismailia) and Kenya (Nairobi) established a surveillance where a network of hospitals with surgical facilities catered to a reference population of about 1–2 million for reporting of intussusception. One large hospital per site also recruited admitted cases of acute watery diarrhoea.
Results:   From April 2004 to March 2006, 173 and 2346 cases of intussusception and diarrhoea, respectively, were recruited. Cases of intussusception had no apparent seasonality. Most cases of intussusception (61.3%) (107/173) were in the ≤1 year age group, with males comprising 68.8% (119/173) of all cases. Hospital mortality of intussusception was 4.2% (4/96). Cases of diarrhoea peaked in March, with 56.6% (1328/2346) of admitted cases being males. Majority (83.1%) of cases of diarrhoea had received antibiotics, and the hospital mortality was 0.8% (18/2280).
Conclusion:   Intussusception in the four participating countries exhibited no seasonal trend. We found that it is feasible to establish a surveillance network for intussusception in developing countries. Future efforts must define population base before the introduction of rotavirus vaccine and continue for some years thereafter.     

Simultaneous presence of human herpesvirus 6 and adenovirus infections in intestinal intussusception of young children

Aim: This prospective study investigated the role of viral infections in the pathogenesis of intussusception, including human herpesvirus 6 (HHV‐6), a known lymphotropic virus. Methods: Fifty‐three children with intussusception treated in hospital were enroled, and children of comparable age and gender served as controls. Blood, stool and throat swab specimens, as well as mesenteric lymph nodes and pieces of intestine from patients requiring surgery were tested for various viruses by PCR methods. Results: Altogether, 85% of intussusception cases showed evidence of a recent or ongoing viral infection. Among the 53 intussusception cases, adenovirus was detected in 25 (47%), HHV‐6 in 24 (45%), rhinovirus in 12 (23%), cytomegalovirus in 7 (13%), enterovirus in 4 (8%) and rotavirus in 3 (6%) patients. Of the 50 whole blood samples, 44% were positive for HHV‐6 and of the 16 resected mesenteric lymph nodes, 50% were positive for HHV‐6. Simultaneous presence of HHV‐6 and adenovirus infection correlated significantly with intussusception (OR 12.1, 95% CI 2.2 to 66.5). Conclusions: A statistically significant association was observed between adenovirus and childhood intussusception. HHV‐6 was a common finding and occurred concomitantly with other viruses. A simultaneous infection with HHV‐6 and adenovirus carried the highest risk for intussusception.     

Successful intervention in a group A meningococcal outbreak in Auckland, New Zealand.

During two consecutive winter seasons (1985 and 1986) Auckland, New Zealand, experienced epidemic rates of Group A meningococcal disease, a pattern not previously recognized in New Zealand. The overall rate was 8.3/100,000/year. The highest annual rate (64.7) occurred in children 0 to 23 months of age. A city-wide vaccine campaign commencing in May, 1987, was conducted over 6 weeks among children 3 months to 13 years of age with special emphasis on reaching populations at highest risk (Maori and Pacific Island Polynesian children in certain geographic regions of Auckland). Children from 2 to 13 years of age received a single dose of monovalent Group A meningococcal vaccine. Children ages 3 to 23 months received two doses at least 1 month apart. Overall approximately 130,000 doses were delivered; coverage was approximately 90% in the single dose target group. Among the younger children approximately 89% received the primary dose. Only approximately 26% received the recommended "booster" dose. After 2 1/2 years of active surveillance (1987 to 1989) there were no cases of invasive Group A meningococcal disease in children appropriately vaccinated for age. In contrast to this 100% efficacy the efficacy of a single dose of monovalent Group A meningococcal vaccine to prevent illness in the youngest children during the 1987 epidemic period was 52% (95% confidence interval (-330%, 95%)) falling to 16% (95% confidence interval, (-538%, 90%)) after 1 year. Four cases that occurred in infants 3 to 7 weeks before the scheduled "booster" campaign supports limited true efficacy. However, the prescribed 1 to 3-month interval between the two doses in infants may be too long.(ABSTRACT TRUNCATED AT 250 WORDS)     

Rotavirus and other enteropathogens in childhood acute diarrhoea: a study of two centres in Malaysia

AIM: To study the role of rotavirus in children hospitalised for acute gastroenteritis (AGE) in two urban hospitals in Malaysia. METHODS: A 12-month prospective study (January to December 2002), in children younger than 14 years with AGE hospitalised to the paediatric units of University of Malaya Medical Centre (UMMC), Kuala Lumpur; and Hospital Sultanah Aminah (HSA), Johor Bahru, Malaysia was conducted. RESULTS: In 2002, 399 and 1307 children with AGE were admitted to UMMC and HSA, respectively. Two hundred and eighty-eight (72%) stool samples from UMMC and 901 (69%) samples from HSA were analysed. Rotavirus was the most common aetiological agent identified in both centres (average 32%; UMMC 35%, HSA 30%, P = 0.94). The peak age group for rotavirus-related hospitalisation was 24-35 months for UMMC and 12-23 months for HSA. Nine percent of patients hospitalised for rotavirus infection in UMMC and 22% of patients in HSA were older than 5 years of age. An outbreak of rotavirus infection within the communities served by both centres resulting in an increase in hospital admissions of rotavirus gastroenteritis was observed in both units from January to March 2002. CONCLUSION: The peak age group for rotavirus-related hospital admission in this study was much older, between 12 to 35 months. It is uncertain whether this was related to the outbreak of rotavirus gastroenteritis observed within two urban areas from January to March 2002 causing re-infection with rotavirus in older children.     

Trends in hospitalization and mortality from rotavirus disease in New Zealand infants.

BACKGROUND: Rotavirus illness is associated with significant morbidity and mortality worldwide. We have examined trends in diarrheal disease in New Zealand children to determine the disease burden attributable to rotavirus and to estimate the proportion of hospitalizations preventable by vaccination. METHODS: Hospital admissions data and laboratory records for 1994 to 1996, were obtained for children 0 to 4 years at four sites (serving -60% of the New Zealand population). Rotavirus disease burden was estimated using combined admissions and laboratory data. Severity of disease was estimated in a sample of 150 hospitalizations for rotavirus diarrhea, and the proportion of vaccine-preventable admissions was extrapolated. Mortality attributed to diarrheal causes was determined from national records for 1974 to 1993. RESULTS: Between 1994 and 1996, 4436 children <5 years of age were hospitalized with diarrhea (1047/100000 children per year). Admissions associated with rotavirus were estimated at 1522 to 1535 (315 to 362/100000 annually). Infants between 6 and 17 months were most commonly affected (42% of all cases). More male children than female children were hospitalized (P < 0.001) and mean length of stay was calculated as 1.51 days (SD 2.35). Disease severity scoring revealed that 61.3 and 38.0% of admissions reviewed were severe and very severe, respectively. Deaths from diarrheal causes numbered 138 among children 0 to 4 years old for the 20-year period 1974 to 1993, with 18 deaths occurring between 1984 and 1993 (10 years). CONCLUSION: Current vaccines control severe disease, suggesting that 72% of cases reviewed would be eligible for prevention. A full cost effectiveness analysis is required to demonstrate anticipated benefits of vaccination.     

Risk factors for intussusception in infants in Vietnam and Australia: adenovirus implicated, but not rotavirus

OBJECTIVE: This study aimed to investigate risk factors for the development of intussusception in infants in a developing country with a suspected high incidence and in a developed country with a low incidence. STUDY DESIGN: A prospective case-control study of infants <2 years of age with idiopathic intussusception confirmed by air enema or surgery was conducted at the National Hospital of Paediatrics (NHP), Vietnam (n = 533) and the Royal Children's Hospital (RCH), Australia (n = 51). Diagnosis was validated in a subset (84% NHP; 67% RCH) by an independent blinded radiologist. Risk factor assessment was performed using a standardized questionnaire. Stool specimens were assayed for bacterial, viral, and parasitic agents. RESULTS: The incidence of intussusception in Vietnam was 302/100,000 in infants <1 year of age (95% CI: 258-352), substantially higher than in Australia (71/100,000). A strong association with adenovirus infection was observed at both sites (cases positive at NHP: 34%, OR 8.2; cases positive at RCH: 40%, OR 44). No association was identified between intussusception and rotavirus, other enteric pathogens, oral polio vaccine, feeding practices, or living conditions. CONCLUSIONS: The incidence of intussusception in infants was markedly higher in Vietnam than in Australia. A strong association between adenovirus infection and intussusception was identified at both sites suggesting that adenovirus may play a role in the etiology of intussusception.     

Rhesus rotavirus vaccine effectiveness and factors associated with receipt of vaccine

BACKGROUND: The rhesus rotavirus tetravalent vaccine (RotaShield) had an efficacy of 75%-100% in preventing severe rotavirus disease in prelicensure clinical trials. Before RotaShield's withdrawal because of reports of intussusception, there was an opportunity to evaluate the postlicensure effectiveness of the vaccine. The objective of this study was to determine the effectiveness of the RotaShield vaccine against rotavirus gastroenteritis requiring hospitalization and to evaluate factors associated with vaccine receipt. METHODS: Rotavirus cases were identified through active hospital-based rotavirus surveillance at 3 children's hospitals in Cincinnati, New Orleans and Providence. Cases were selected if they had been eligible for vaccine during the 10-month period when vaccine was available. Controls were matched to cases by date and county or state of birth. Immunization records were obtained from cases and controls to document receipt of RotaShield. Vaccine effectiveness (VE) was calculated for 1, 2, and 3 doses of vaccine with 95% confidence intervals (CI). RESULTS: For the 10-month period, 136 cases and 440 controls were enrolled. For 3 versus 0 doses of RotaShield, the VE was 100% (CI: 75%, 100%); for 2 versus 0 doses, the VE was 100% (CI: 62%, 100%), and for 1 versus 0 doses the VE was 89% (CI: 49%, 97%). RotaShield receipt was associated with white race, having more than 1 adult in the household, having insurance and having an older, more educated mother. CONCLUSIONS: This postlicensure study of RotaShield effectiveness found the vaccine to be highly effective in preventing rotavirus disease requiring hospitalization.