Hospitalizations associated with rotavirus diarrhea in the United States, 1993 through 1995: surveillance based on the new ICD-9-CM rotavirus-specific diagnostic code

Why Aren't We Achieving High Vaccination Rates for Rotavirus Vaccine in the United States?

BACKGROUND

Rotavirus vaccine (RV) coverage levels for US infants are <80%.

METHODS

We surveyed nationally representative networks of pediatricians by internet/mail from April to June, 2019. Multivariable regression assessed factors associated with difficulty administering the first RV dose (RV#1) by the maximum age.

RESULTS

Response rate was 68% (303/448). Ninety-nine percent of providers reported strongly recommending RV. The most common barriers to RV delivery overall (definite/somewhat of a barrier) were: parental concerns about vaccine safety overall (27%), parents wanting to defer (25%), parents not thinking RV was necessary (12%), and parent concerns about RV safety (6%). The most commonly reported reasons for nonreceipt of RV#1 by 4 to 5 months (often/always) were parental vaccine refusal (9%), hospitals not giving RV at discharge from nursery (7%), infants past the maximum age when discharged from neonatal intensive care unit/nursery (6%), and infant not seen before maximum age for well care visit (3%) or seen but no vaccine given (4%). Among respondents 4% strongly agreed and 25% somewhat agreed that they sometimes have difficulty giving RV#1 before the maximum age. Higher percentage of State Child Health Insurance Program/Medicaid-insured children in the practice and reporting that recommendations for timing of RV doses are too complicated were associated with reporting difficulty delivering the RV#1 by the maximum age.

CONCLUSIONS

US pediatricians identified multiple, actionable issues that may contribute to suboptimal RV immunization rates including lack of vaccination prior to leaving nurseries after prolonged stays, infants not being seen for well care visits by the maximum age, missed opportunities at visits and parents refusing/deferring.

Epidemiology of acute diarrhea caused by rotavirus in sentinel surveillance sites of Vietnam, 2012-2015

A prospective, multicentre study was conducted in four sentinel surveillance hospitals to assess the trend and epidemiology of acute diarrhea caused by Rotavirus in Vietnam. During the period 2012-2015, a total 8,889 children under 5 years of age were enrolled in the surveillance, and 8689 stool samples were collected. Of these cases, Rotavirus was most common pathogen 46.7% (4054 cases); in which 26.6% (1117) rotavirus-positive stool samples were evaluated to identify genotypes. The proportion of rotavirus positive specimens decreased annually from 54.7% in 2012 to 36.6% in 2015. Rotavirus was detected year-round, but most rotavirus gastroenteritis cases (77.1%) occurred between December and May, corresponding to the rotavirus seasonality. It is found that the peaks varied by regions. Rotavirus positivities varied between the youngest and oldest age, but children 6-11 months old (38.8%) and 12-23 months old (38.4%) counted for most cases. A significant higher number of diarrhea within 24 hours (8.3 times, 95%CI: 8.1-8.4 times) and higher proportion of severe dehydration (12.9%) in Rotavirus positive group than that in Rotavirus negative group (7.7 times, 95%CI: 7.6-7.9 times; and 9.7%, respectively). A downtrend of prevalence of G1P[8] was observed from 82% in 2013 to 15% in 2015. However, G2P[4] was found in 5% of samples in 2012, 9% in 2013, 36% in 2014, and 28% in 2015. Rotavirus infection is the most important cause of acute diarrhea among hospitalized children in Vietnam, and a rotavirus vaccination program for children may significantly reduce this disease.

Pediatric hospitalizations attributable to rotavirus gastroenteritis among Cambodian children: Seven years of active surveillance, 2010-2016

BACKGROUND

Each year, approximately 1,066 Cambodian children under five years old die of diarrhea, and 51% of these deaths are due to rotavirus gastroenteritis. Quantifying childhood hospitalizations caused by severe rotavirus infections is also important in demonstrating disease burden caused by this virus. The objective of this study is to update and confirm the current burden of pediatric hospitalizations attributable to rotavirus gastroenteritis among Cambodian children using seven years of continuous active, prospective surveillance from 2010 to 2016. We also characterize the circulating rotavirus genotypic strains during this period.

METHODS

Active surveillance for rotavirus gastroenteritis was conducted from January 2010 through December 2016 at a national hospital in Phnom Penh, Cambodia. Children <60 months of age who were hospitalized for acute gastroenteritis (AGE) were consented and enrolled. Information on gender, age, clinical characteristics, and month of onset were collected. Stool specimens were collected and tested by enzyme immunoassay for the presence of rotavirus antigen, and genotyping was performed on rotavirus test-positive specimens to characterize predominant rotavirus strains during the surveillance period.

RESULTS

Of 7007 children enrolled with AGE and having specimens collected, 3473 (50%) were attributed to rotavirus gastroenteritis. The majority of rotavirus hospitalizations occurred in children younger than two years old (92%). Year-round rotavirus transmission was observed, with seasonal peaks during the cooler, dry months between November and May. Genotypic trends in rotavirus were observed over the surveillance period; the predominant rotavirus strains changed from G1P[8] (2010-2012), to G2P[4] (2013-2014), the emergence of genotype G8P[8] in 2015, and G3P[8] in 2016.

CONCLUSIONS

Rotavirus is the leading cause of severe acute gastroenteritis hospitalizations in Cambodian children under five years old, with 50% of such hospitalizations attributable to rotavirus. Over 90% of rotavirus hospitalizations occurred in children under 2 years of age. Changes in the predominant rotavirus strains occurred over time among these unvaccinated children. This information is important to understand and prioritize the current potential impacts upon child health that could be achieved through the introduction of rotavirus vaccines in Cambodia.

Genomics and Foodborne Viral Infections

Foodborne viral illness, resulting from the consumption of contaminated food or water containing pathogenic viruses, remains a major public health problem globally with substantial economic impact. Major challenges regarding recognizing, detecting, characterizing, and effectively responding to foodborne viral threats to health exist. Adequate health crisis management is largely dependent on early detection of potential public health threats, which is hampered by changing trends in disease outbreaks, from localized clusters of disease in confined populations to dispersed outbreaks with excellent opportunity for further transmission. In addition, no precise and consistent global baseline syndrome and diagnostic surveillance information exists. An integrated multidisciplinary approach with a combination of sustained pathogen syndrome and diagnostic surveillance, genomics-based, and standardized global analytical networks gathering clinical, epidemiological and genetic data alike would be required to understand the dynamics of foodborne viral infection and to mitigate potential effects of future threats. A huge global effort in virus syndrome and diagnostic surveillance may be justified in the light of global health impact in general, and timely with the development of new metagenomics tools that hold the promise of not only identifying viral pathogens, but possibly the complete microbiome in a single assay.

Rotavirus vaccine and health-care utilization for rotavirus gastroenteritis in Tsu City, Japan

Background

Rotavirus vaccines were introduced in Japan in November 2011. We evaluated the subsequent reduction of the health-care burden of rotavirus gastroenteritis.

Methods

We conducted active surveillance for rotavirus gastroenteritis among children under 5 years old before and after the vaccine introduction. We surveyed hospitalization rates for rotavirus gastroenteritis in children in Tsu City, Mie Prefecture, Japan, from 2007 to 2015 and surveyed the number of outpatient visits at a Tsu City clinic from 2010 to 2015. Stool samples were obtained for rotavirus testing and genotype investigation. We assessed rotavirus vaccine coverage for infants living in Tsu City.

Results

In the pre-vaccine years (2007–2011), hospitalization rates for rotavirus gastroenteritis in children under 5 years old were 5.5, 4.3, 3.1 and 3.9 cases per 1000 person-years, respectively. In the post-vaccine years (2011–2015), the rates were 3.0, 3.5, 0.8 and 0.6 cases per 1000 person-years, respectively. The hospitalization rate decreased significantly in the 2013–2014 and 2014–2015 seasons compared to the average of the seasons before vaccine introduction (P < 0.0001). In one pre-vaccine year (2010–2011), the number of outpatient visits due to the rotavirus infection was 66. In the post-vaccine years (2011–2015), the numbers for each season was 23, 23, 7 and 5, respectively. The most dominant rotavirus genotype shifted from G3P[8] to G1P[8] and to G2P[4]. The coverage of one dose of rotavirus vaccine in Tsu City was 56.5% in 2014.

Conclusion

After the vaccine introduction, the hospitalization rates and outpatient visits for rotavirus gastroenteritis greatly decreased.

Public Health Impact of Complete and Incomplete Rotavirus Vaccination among Commercially and Medicaid Insured Children in the United States

Background

This study (NCT01682005) aims to assess clinical and cost impacts of complete and incomplete rotavirus (RV) vaccination.

Methods

Beneficiaries who continuously received medical and pharmacy benefits since birth were identified separately in Truven Commercial Claims and Encounters (2000–2011) and Truven Medicaid Claims (2002–2010) and observed until the first of end of insurance eligibility or five years. Infants with ≥1 RV vaccine within the vaccination window (6 weeks-8 months) were divided into completely and incompletely vaccinated cohorts. Historically unvaccinated (before 2007) and contemporarily unvaccinated (2007 and after) cohorts included children without RV vaccine. Claims with International Classification of Disease 9^th edition (ICD-9) codes for diarrhea and RV were identified. First RV episode incidence, RV-related and diarrhea-related healthcare resource utilization after 8 months old were calculated and compared across groups. Poisson regressions were used to generate incidence rates with 95% confidence intervals (CIs). Mean total, inpatient, outpatient and emergency room costs for first RV and diarrhea episodes were calculated; bootstrapping was used to construct 95% CIs to evaluate cost differences.

Results

1,069,485 Commercial and 515,557 Medicaid patients met inclusion criteria. Among commercially insured, RV incidence per 10,000 person-years was 3.3 (95% CI 2.8–3.9) for completely, 4.0 (95% CI 3.3–5.0) for incompletely vaccinated, and 20.9 (95% CI 19.5–22.4) for contemporarily and 40.3 (95% CI 38.6–42.1) for historically unvaccinated. Rates in Medicaid were 7.5 (95% CI 4.8–11.8) for completely, 9.0 (95% CI 6.5–12.3) for incompletely vaccinated, and 14.6 (95% CI 12.8–16.7) for contemporarily and 52.0 (95% CI 50.2–53.8) for historically unvaccinated. Mean cost for first RV episode per cohort member was $15.33 (95% CI $12.99-$18.03) and $4.26 ($95% CI $2.34-$6.35) lower for completely vaccinated versus contemporarily unvaccinated in Commercial and Medicaid, respectively.

Conclusions

RV vaccination results in significant reduction in RV infection. There is evidence of indirect benefit to unvaccinated individuals.

Multiplexed one-step RT-PCR VP7 and VP4 genotyping assays for rotaviruses using updated primers

The current two-step VP7 and VP4 genotyping RT-PCR assays for rotaviruses have been linked consistently to genotyping failure in an estimated 30% of RVA positive samples worldwide. We have developed a VP7 and VP4 multiplexed one-step genotyping assays using updated primers generated from contemporary VP7 and VP4 sequences. To determine assay specificity and sensitivity, 17 reference virus strains, 6 non-target gastroenteritis viruses and 725 clinical samples carrying the most common VP7 (G1, G2, G3, G4, G9, and G12) and VP4 (P[4], P[6], P[8], P[9] and P[10]) genotypes were tested in this study. All reference RVA strain targets yielded amplicons of the expected sizes and non-target genotypes and gastroenteritis viruses were not detected by either assay. Out of the 725 clinical samples tested, the VP7 and VP4 assays were able to assigned specific genotypes to 711 (98.1%) and 714 (98.5%), respectively. The remaining unassigned samples were re-tested for RVA antigen using EIA and qRT-PCR assays and all were found to be negative. The overall specificity, sensitivity and limit of detection of the VP7 assay were in the ranges of 99.0-100%, 94.0-100% and 8.6×10(1) to 8.6×10(2) copies of RNA/reaction, respectively. For the VP4 assay, the overall specificity, sensitivity and limit of detection assay were in the ranges of 100%, 94.0-100% and ≤1 to 8.6×10(2) copies of RNA/reaction, respectively. Here we report two highly robust, accurate, efficient, affordable and documentable gel-based genotyping systems which are capable of genotyping 97.8% of the six common VP7 and 98.3% of the five common VP4 genotypes of RVA strains which are responsible for approximately 88.2% of all RVA infections worldwide.

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 and cost burden of rotavirus infection before and after introduction of rotavirus vaccines among commercially and Medicaid insured children in the United States

This study aims to quantify clinical and economic burden of rotavirus (RV) infection pre- and post-vaccine introduction in commercially insured and Medicaid populations. Beneficiaries with continuous enrollment for ≥6 months while <5 years of age were identified separately in commercial (2000–2010) and Medicaid (2002–2009) claims databases. Commercial and Medicaid databases included 3 998 708 and 1 034 440 eligible children, respectively, observed from enrollment start date(s) to end of eligibility or 5-years-old. Rates of RV-coded and diarrhea-coded encounters and first RV episodes, and incremental cost of first RV episodes were calculated. In the post-vaccine period, rates per 10 000 person-years for RV-coded hospitalizations, outpatient visits and ER visits were 5.58 (95% CI, 5.37–5.80), 6.96 (95% CI, 6.75–7.20), and 4.85 (95% CI, 4.66–5.06), respectively (pre-vaccine, 16.67 [95% CI, 16.19–17.15], 13.20 [95% CI, 12.78–13.63], 11.26 [95% CI, 10.87–11.66], respectively), for commercially insured. In Medicaid the corresponding rates were 10.53 (95% CI, 9.60–11.56), 11.72 (95% CI, 10.73–12.80), and 9.11 (95% CI, 8.24–10.07) (pre-vaccine, 19.78 [95% CI, 19.14–20.45], 19.39 [95% CI, 18.75–20.05], 27.61 [95% CI, 26.84–28.40]). Incidence rate per 10 000 person-years for first RV episode pre- vs. post-vaccine were 27.03 (95% CI, 26.42–27.65) vs. 10.14 (95% CI, 9.86–10.44) in the commercially insured population and 37.71 (95% CI, 36.81–38.63) vs. 18.64 (95% CI, 17.37–19.99) in Medicaid. Incremental per-patient per-month cost of first RV episode was $3363 (95% CI, $3308-$3418) among commercially insured and $1831 (95% CI, $1768-$1887) in Medicaid. Since vaccine introduction clinical burden of RV disease decreased among children; costs associated with RV episodes remained significant across insured populations.

Rotarix™ (RIX4414): an oral human rotavirus vaccine

Rotavirus is the most common cause of severe gastroenteritis in children younger than 3 years of age worldwide. New rotavirus vaccine candidates were required to confer early protection against the most common rotavirus serotypes and to be well tolerated and not associated with intussusception. RIX4414 is a human-attenuated G1(P8) oral rotavirus vaccine administered in two doses at approximately 6-24 weeks of age. The first dose may be administered from the age of 6 weeks. There should be an interval of at least 4 weeks between doses and the vaccination course should preferably be given before 16 weeks of age and must be completed, according to the manufacturer, by the age of 24 weeks. In a worldwide development program involving more than 70,000 children in six Phase I-III field trials, this vaccine proved to be nonreactogenic, well tolerated and not associated with intussusception. The vaccine provides over 85-96% protection against moderate-to-severe gastroenteritis caused by G1 and non-G1 serotypes, as demonstrated in Latin American and European clinical trial settings, respectively; and reduces gastroenteritis-related hospitalizations by more than 40% in Latin America and by 75% in European settings.

High burden of rotavirus gastroenteritis in young children in rural western Kenya, 2010-2011

BACKGROUND

Diarrhea is a leading cause of hospitalization and death in children <5 years of age.

OBJECTIVES

To facilitate evaluation of the impact of rotavirus vaccine introduction in western Kenya, we estimated baseline rates of rotavirus-associated hospitalization and mortality among children <5 years of age.

METHODS

From January 2010 to December 2011, we collected demographic, clinical and laboratory data for children <5 years of age seeking care at the district hospital and 2 outpatient facilities within a Health and Demographic Surveillance System (HDSS). Children with acute gastroenteritis (AGE), defined as ≥3 loose stools and/or ≥1 episode of unexplained vomiting followed by loose stool within a 24-hour period, were asked to provide a stool sample for rotavirus ELISA testing. Rates of rotavirus-associated hospitalization and mortality were estimated using time of residence in the HDSS to calculate person-years of observation. To estimate the rotavirus-associated mortality rate, we applied the percentage positive for rotavirus among AGE hospitalizations to verbal autopsy estimates of diarrhea deaths in the HDSS.

RESULTS

There were 4991 hospitalizations of children <5 years of age; 1134 (23%) were for AGE and stool specimens were obtained from 790 (70%). Rotavirus was detected in 211 (27%) specimens. Among 4951 <5 outpatient sick visits, 608 (12%) were for AGE; 320 (51%) provided specimens and 62 (20%) were positive for rotavirus. Rotavirus AGE accounted for 501 <5 hospitalizations per 100,000 person-years of observation. Rotavirus-associated <5 mortality was 136 deaths per 100,000 person-years of observation.

CONCLUSIONS

Continued surveillance of rotavirus AGE will provide timely data on the population-level impact of rotavirus vaccine following its likely introduction in 2014.

Hospitalizations and deaths caused by diarrhea in children five years old and younger at four hospitals in Haiti, 2010-2012

Worldwide, diarrhea is a major contributor to morbidity and mortality in children; however, there are few data on the burden of diarrheal disease in Haiti. We conducted a retrospective review of hospital discharge registries from 2010 to 2012 in the pediatric wards of four Haitian hospitals and recorded the number of all-cause hospitalizations and deaths as well as diarrheal hospitalizations and deaths by age (≤ 2 and 3-5 years) and epidemiological week. Diarrhea was associated with 3,582 (33.7%) of 10,621 hospitalizations and 62 (11.5%) of 540 in-hospital deaths in children ≤ 5 years old. Of these children, 88.5% and 96.8%, respectively, were among children ≤ 2 years old. The highest proportions of diarrhea-associated hospitalizations occurred from January to April. At four Haitian hospitals over a 3-year period, during which time a major epidemic of cholera occurred, diarrheal disease in children ≤ 5 years was a major contributor to pediatric hospitalizations and mortality.

Rotavirus seasonality and age effects in a birth cohort study of southern India

INTRODUCTION

Understanding the temporal patterns in disease occurrence is valuable for formulating effective disease preventive programs. Cohort studies present a unique opportunity to explore complex interactions associated with emergence of seasonal patterns of infectious diseases.

METHODS

We used data from 452 children participating in a birth cohort study to assess the seasonal patterns of rotavirus diarrhea by creating a weekly time series of rotavirus incidence and fitting a Poisson harmonic regression with biannual peaks. Age and cohort effects were adjusted for by including the weekly counts of number of children in the study and the median age of cohort in a given week. Weekly average temperature, humidity and an interaction term to reflect the joint effect of temperature and humidity were included to consider the effects of meteorological variables.

RESULTS

In the overall rotavirus time series, two significant peaks within a single year were observed--one in winter and the other in summer. The effect of age was found to be the most significant contributor for rotavirus incidence, showing a strong negative association. Seasonality remained a significant factor, even after adjusting for meteorological parameters, and the age and cohort effects.

CONCLUSIONS

The methodology for assessing seasonality in cohort studies is not yet developed. This is the first attempt to explore seasonal patterns in a cohort study with a dynamic denominator and rapidly changing immune response on individual and group levels, and provides a highly promising approach for a better understanding of the seasonal patterns of infectious diseases, tracking emergence of pathogenic strains and evaluating the efficacy of intervention programs.

Prevalence, seasonality and severity of disease caused by pathogenic Escherichia coli in children with diarrhoea in Bolivia

The prevalence of infection caused by different categories of diarrhoeagenic E. coli (DEC) strains, including enteroaggregative (EAEC), enteropathogenic (EPEC), enterotoxigenic (ETEC), enteroinvasive (EIEC) and enterohaemorrhagic (EHEC) E. coli, in children who suffered from diarrhoea (n = 3943) or did not have diarrhoea (n = 1026) were analysed in two areas in Bolivia over a period of 4 years. We also analysed the seasonality of DEC infections and severity of diarrhoea in children with DEC infection and compared antibiotic resistance in DEC strains isolated from children with and without diarrhoea. Stool samples were analysed for the presence of DEC by culturing followed by PCR. The most prevalent DEC categories in samples from the children were: EAEC (11.2 %); ETEC (6.6 %); EPEC (5.8 %); and EIEC and EHEC (<1 %). DEC strains were isolated significantly more often from diarrhoea cases (21.6 %) than from controls (17.6 %; P = 0.002). The number of children with diarrhoea associated with EAEC, EPEC and ETEC infections peaked in the Bolivian winter (April-September), although the proportion of DEC-positive stool samples was higher during the warm rainy season (October-March). High levels of antibiotic resistance were detected among the DEC strains. In particular, resistance to tetracycline and sulfamethoxazole-trimethoprim was significantly higher in strains isolated from individuals with diarrhoea than in samples from controls. The severity of disease in children infected with EAEC, EPEC and ETEC varied from mild to severe diarrhoea, although disease severity did not differ significantly between the different DEC categories. ETEC, EPEC and EAEC are commonly found in Bolivia and may cause severe disease in children.

Rotavirus-associated hospitalization and emergency department costs and rotavirus vaccine program impact

OBJECTIVES

To determine the medical costs of laboratory-confirmed rotavirus hospitalizations and emergency department (ED) visits and estimate the economic impact of the rotavirus vaccine program.

PATIENTS AND METHODS

During 4 rotavirus seasons (2006-2009), children <3 years of age hospitalized or seen in the ED with laboratory-confirmed rotavirus were identified through active population-based rotavirus surveillance in three US counties. Medical costs were obtained from hospital and physician billing data, and factors associated with increased costs were examined. Annual national costs were estimated using rotavirus hospitalization and ED visit rates and medical costs for rotavirus hospitalizations and ED visits from our surveillance program for pre- (2006-2007) and post-vaccine (2008-2009) time periods.

RESULTS

Pre-vaccine, for hospitalizations, the median medical cost per child was $3581, the rotavirus hospitalization rate was 22.1/10,000, with an estimated annual national cost of $91 million. Post-vaccine, the median medical cost was $4304, the hospitalization rate was 6.3/10,000 and the estimated annual national cost was $31 million. Increased costs were associated with study site, age <3 months, underlying medical conditions and an atypical acute gastroenteritis presentation. For ED visits, the pre-vaccine median medical cost per child was $574, the ED visit rate was 291/10,000 resulting in an estimated annual national cost of $192 million. Post-vaccine, the median medical cost was $794, the ED visit rate was 71/10,000 with an estimated annual national cost of $65 million.

CONCLUSIONS

After implementation of rotavirus immunization, the total annual medical costs decreased from $283 million to $96 million, an annual reduction of $187 million.

Targeted rotavirus vaccination of high-risk infants; a low cost and highly cost-effective alternative to universal vaccination

BACKGROUND

The cost-effectiveness of universal rotavirus (RV) vaccination is controversial in developed countries. As a result, RV vaccination programs do not currently exist in most European countries. Hospitalization is the main driver of RV disease costs, and prematurity, low birth weight (LBW) and underlying medical conditions have been associated with RV hospitalization and complications. We investigated the cost-effectiveness of targeted RV vaccination of high-risk infants and universal RV vaccination versus no vaccination.

METHODS

Disease burden, mortality and healthcare costs of RV hospitalization for children with and without prematurity, LBW and congenital pathology were quantified in two hospital-based observational studies in the Netherlands. Cost-effectiveness analysis was based on an age-structured stochastic multi-cohort model of the Dutch population comparing universal RV vaccination and targeted vaccination of high-risk infants to no vaccination. The primary endpoint was the incremental cost-effectiveness ratio (ICER), with a threshold of €35,000/quality-adjusted life year (QALY) from the healthcare provider perspective. Sensitivity analyses included vaccine price and coverage, herd-immunity and QALY losses.

RESULTS

A total of 936 children with RV infection were included. Prematurity, LBW and congenital pathology were associated with increased risks of RV hospitalization (relative risks (RR) ranging from 1.6 to 4.4), ICU admission (RR ranging from 4.2 to 7.9), prolonged hospital stay (1.5 to 3.0 excess days) and higher healthcare costs (€648 to €1,533 excess costs). Seven children succumbed due to RV complications, all belonging to the high-risk population. Targeted RV vaccination was highly cost-effective and potentially cost-saving from the healthcare provider perspective with ICERs below €20,000/QALY in all scenarios with total (undiscounted) annual healthcare costs between -€0.1 and €0.5 million/year. Results were most sensitive to mortality rates, but targeted vaccination remained highly cost-effective up to reductions of 90% compared to observed mortality. Universal RV vaccination was not considered cost-effective (mean ICER: €60,200/QALY) unless herd-immunity and caretaker QALY losses were included and vaccine prices were €60 at most (mean ICER: €21,309/QALY).

CONCLUSION

We recommend targeted RV vaccination for high-risk infants in developed countries.

Determining the effectiveness of the pentavalent rotavirus vaccine against rotavirus hospitalizations and emergency department visits using two study designs

The objective of this study is to determine the vaccine effectiveness (VE) of the pentavalent rotavirus vaccine (RV5) for preventing rotavirus-related hospitalizations and emergency department (ED) visits during the 2006-07 and 2007-08 rotavirus seasons using two study designs. Active, prospective population-based surveillance was conducted to identify cases of laboratory-confirmed rotavirus-related hospitalizations and ED visits to be used in case-cohort and case-control designs. VE was calculated using one comparison group for the case-cohort method and two comparison groups for the case-control method. The VE estimates produced by the three analyses were similar. Three doses of RV5 were effective for preventing rotavirus-related hospitalizations and ED visits in each analysis, with VE estimated as 92% in all three analyses. Two doses of RV5 were also effective, with VE ranging from 79% to 83%. A single dose was effective in the case-cohort analysis, but was not significant in either of the case-control analyses. The case-cohort and the case-control study designs produced the same VE point estimates for completion of the three dose series. Two and three doses of RV5 were effective in preventing rotavirus-related hospitalizations and ED visits.

Rotavirus-related hospitalizations are responsible for high seasonal peaks in all-cause pediatric hospitalizations

BACKGROUND

Seasonal rotavirus (RV) epidemics partly overlap with those of other common childhood infections, thereby generating enormous, but poorly quantified, pressure on hospital resources during winter and spring. We assessed RV contribution to seasonal excess in all-cause pediatric hospitalizations and RV hospitalization incidence rate in an observational study.

METHODS

The study was conducted among pediatric wards in 3 general hospitals and 1 pediatric tertiary care center. Numbers of RV hospitalizations were determined from 5-year data on confirmed RV hospitalizations and adjusted for RV underreporting, assessed through active surveillance for acute gastroenteritis during the 2011 RV season. Incidence rate and RV contribution to all-cause hospitalizations were determined on hospital administrative data and population statistics.

RESULTS

RV accounted for 6.2% (95% confidence interval: 5.3-7.1) of all-cause pediatric hospitalizations among general hospitals and 3.1% (95% confidence interval: 2.9-3.3) at the tertiary care center, adjusted for the proportion RV underreporting among gastroenteritis patients (33%) as observed during active surveillance. Among general hospitals, there was a 30% increase in all-cause hospitalizations during the active season of common childhood infections compared with summer months. RV contributed 31% to seasonal excess in all-cause pediatric hospitalizations, representing 12.9% of hospitalizations between January and May. RV hospitalizations incidence rate in the population was 510/100,000 child-years <5 years (95% confidence interval: 420-600).

CONCLUSION

RV is one of the main causes of seasonal peaks in pediatric hospitalizations, and as such contributes significantly to periodic high bed capacity pressures and associated adverse effects. RV vaccination benefits in this respect should be considered in decision-making processes.

Burden of rotavirus hospitalisations in young children in three paediatric hospitals in the United States determined by active surveillance compared to standard indirect methods

AIM

  The number of rotavirus hospitalisations is usually estimated from assigned diagnosis codes for gastroenteritis despite lack of validation for these indirect methods. Reliable estimates before and after introduction of vaccines are needed to quantify the absolute impact of new immunisation programs.

METHODS

  This 2-year study conducted at three hospitals prior to the licensure of the rotavirus vaccines in the USA compared two indirect methods for estimating hospitalisations for rotavirus gastroenteritis with estimates derived from prospective recruitment of children presenting with diarrhoea, vomiting or fever. For active surveillance, rotavirus gastroenteritis was confirmed by demonstration of stool antigen. The indirect residual and proportional methods assumed rotavirus to have caused a proportion of hospitalisations coded as acute gastroenteritis identified from computerised records.

RESULTS

  There were 447 rotavirus hospitalisations among inpatients 31 days through 4 years of age admitted with vomiting and/or diarrhoea, compared with 306 and 228 hospitalisations identified by the two indirect methods. Only 52% of children hospitalised with gastroenteritis received a qualifying diagnosis code at discharge. Relative to active surveillance, the sensitivity and specificity (95% confidence interval (CI)) in identifying rotavirus-attributable hospitalisations was 45% (95% CI: 43-48%) and 89% (88-90%) for the residual method and 34% (30-39%) and 92% (90-94%) for the proportional method.

CONCLUSIONS

  Many children admitted to the hospital with diarrhoea, vomiting or fever were not assigned discharge codes for acute gastroenteritis. Consequently, standard indirect methods missed a substantial number of rotavirus-associated hospitalisations, thereby underestimating the absolute number of children who could potentially benefit from vaccination.

The effect of routine rotavirus vaccination on healthcare utilization for diarrhea in US children

Evaluation of: Cortes JE, Curns AT, Tate JE et al. Rotavirus vaccine and health care utilization for diarrhea in U.S. children. N. Engl. J. Med. 365(12), 1108–1117 (2011). Cortes et al. thoroughly analyzed the effect of the introduction of mass rotavirus vaccination on healthcare utilization in a population of approximately 2 million US children under 5 years of age. According to the results of the study, hospitalization has been reduced from prevaccination periods by 89% for rotavirus diarrhea and by 44% for diarrheal disease. The estimated reduction of hospitalizations during the two (single-year) periods amounted to 64,855 and the respective savings in treatment costs were US$278 million. The significance of this paper is its approach to the estimation of vaccine efficacy by the assessment of vaccination coverage and hospitalization, as well as emergency department and outpatient visits in a large population of children without any ‘selection’ (e.g., hospitalization) bias.

Increased prevalence of rotavirus among children associated gastroenteritis in Riyadh Saudi Arabia

The aim of this study is to assess the epidemiology along with the molecular structure of rotavirus causing pediatric diarrhea among Saudi patients. However, in this report we sited the epidemiological reflect coming from our project.

Hospitalizations for diarrhea in Quebec children from 1985 to 1998: estimates of rotavirus-associated diarrhea

OBJECTIVE

To characterize the incidence and duration of hospitalization due to diarrhea and to assess the proportion of hospitalizations that are attributed to rotavirus-associated diarrhea.

DESIGN

Retrospective study of hospitalization data.

SETTING

Hospitals located in Quebec.

POPULATION STUDIED

Children from one to 59 months of age who were discharged from hospital from April 1, 1985 to March 31, 1998.

MAIN RESULTS

There were 63,827 hospitalizations for diarrhea over the study period, for an average of 4910 hospitalizations/year. The epidemic curve showed a periodicity with regular alternation of high and low annual peaks. The number of hospitalizations for rotavirus-associated diarrhea was estimated according to three different methods. The estimates varied between 1353 and 1849 hospitalizations due to rotavirus-associated diarrhea/year over the 13-year period, with good agreement between the results of the three methods for a one-month to five years of age incidence of 320 hospitalizations for rotavirus-associated diarrhea/100,000 children. The average duration of hospital stay decreased from 5.2 days in 1985 to 3.3 days in 1998.

CONCLUSIONS

The present article shows the importance of diarrhea hospitalizations among children and the alternating peak-year periodicity.

Baseline estimates of diarrhea-associated mortality among United States children before rotavirus vaccine introduction

OBJECTIVES

Deaths due to diarrhea among US children declined substantially from the 1960s through the 1980s, but have not been recently assessed. We examined diarrhea-associated mortality among young US children from 1992 to 2006 to establish baseline estimates through which the effect of rotavirus vaccines, introduced in 2006, can be assessed.

METHODS

National Center for Health Statistics multiple cause-of-death mortality data were used to examine diarrhea-associated deaths and death rates among US children 1 to 59 months of age during 1992-2006. The winter residual method was used to indirectly estimate the annual number of diarrhea-associated deaths attributable to rotavirus.

RESULTS

An average of 369 diarrhea-associated deaths/year (3320 total deaths) occurred among US children 1 to 59 months of age during 1992-1998 and 2005-2006. The diarrhea-associated death rate increased 40% between the first 3 and last 2 years of the study period, from an average of 1.6 deaths per 100,000 to 2.3 deaths per 100,000. Black children died at almost 4 times the rate of white children. Diarrhea-associated deaths showed a winter seasonal pattern similar to that of rotavirus, particularly among children 4 to 23 months of age. Using indirect methods, we estimated 25 yearly rotavirus-associated deaths during the study period. Rotavirus vaccination could potentially prevent 21 of these deaths annually.

CONCLUSIONS

Diarrhea-associated mortality among US children stabilized but appears to be increasing in recent years. Rotavirus was associated with a small but significant number of preventable deaths. The national multiple cause-of-death data should prove useful for assessing mortality impact of rotavirus vaccination in the United States.

Effectiveness of pentavalent rotavirus vaccine against severe disease

OBJECTIVE

To determine the vaccine effectiveness (VE) of complete and partial vaccination with the pentavalent rotavirus vaccine (RV5) in the prevention of rotavirus acute gastroenteritis (AGE) hospitalizations and emergency department visits during the first 3 rotavirus seasons after vaccine introduction.

METHODS

Active, prospective population-based surveillance for AGE and acute respiratory infection (ARIs) in inpatient and emergency department settings provided subjects for a case-control evaluation of VE in 3 US counties from January 2006 through June 2009. Children with laboratory-confirmed rotavirus AGE (cases) were matched according to date of birth and onset of illness to 2 sets of controls: children with rotavirus-negative AGE and children with ARI. The main outcome measure was VE with complete (3 doses) or partial (1 or 2 doses) RV5 vaccination.

RESULTS

Of age-eligible children enrolled, 18% of cases, 54% of AGE controls, and 54% of ARI controls received ≥1 dose of RV5. The VE of RV5 for 1, 2, and 3 doses against all rotavirus genotypes with the use of rotavirus-negative AGE controls was 74% (95% confidence interval [CI]: 37%-90%), 88% (95% CI: 66%-96%), and 87% (95% CI: 71%-94%), respectively, and with the use of ARI controls was 73% (95% CI: 43%-88%), 88% (95% CI: 68%-95%), and 85% (95% CI: 72%-91%), respectively. The overall VE estimates were comparable during the first and second years of life and against AGE caused by different rotavirus strains.

CONCLUSION

RV5 was highly effective in preventing severe rotavirus disease, even after a partial series, with protection persisting throughout the second year of life.

Probiotics in the treatment of acute rotavirus diarrhoea. A randomized, double-blind, controlled trial using two different probiotic preparations in Bolivian children

BACKGROUND

Evidence suggests that probiotics reduce rotavirus diarrhoea duration. Although there are several probiotic strains potentially useful, daily practice is often limited by the type and number of products locally available. In general, information about combined products is scarce. In this study we compare the effect of two probiotic products in the treatment of diarrhoea in children less than 2 years of age.

METHODS

A Randomized double-blind controlled clinical trial in children hospitalized for acute rotavirus diarrhoea, in the Paediatric Centre Albina Patino, Cochabamba, Bolivia.Participants were children aged 1 - 23 months, who were randomly assigned to receive one of three treatments: Oral rehydration therapy plus placebo; Oral rehydration solution plus Saccharomyces boulardii; or Oral rehydration solution plus a compound containing Lactobacillus acidophilus, Lactobacillus rhamnosus, Bifidobacterium longum and Saccharomyces boulardii. Sample size was 20 per group and the outcomes were duration of diarrhoea, of fever, of vomiting and of hospitalization.

RESULTS

64 cases finished the protocol. On admission, patients' characteristics were similar. Median duration of diarrhoea (p = 0.04) in children who received the single species product (58 hours) was shorter than in controls (84.5 hrs). Comparing children that received the single probiotic product and controls showed shorter duration of fever (18 vs 67 hrs) (p = 0.0042) and the mixed probiotic of vomiting (0 vs 42.5 hrs) (p = 0.041). There was no effect on duration of hospitalization (p = 0.31). When experimental groups were merged, statistical significance of changes increased (total duration of diarrhoea, fever and vomiting P = 0.025, P = 0.025 and P = 0.014, respectively).

CONCLUSIONS

Both products decreased the duration of diarrhoea compared to oral rehydration solution alone. This decrease was significant only for the single species product which also decreased the duration of fever. With the multiple species product there was no vomiting subsequent to the initiation of treatment. The quantity of probiotic bacteria needed for optimum treatment of gastroenteritis remains to be determined, particularly when multiple species are included in the product.Trial registration: ClinicalTrials.gov ID: NCT00981877Link: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol/sid/S0002653/selectaction/View/ts/2/uid/U0000N04

TRIAL REGISTRATION

Clinical trials NCT ID: NCT00981877.

Epidemiological and clinical features of rotavirus among children younger than 5 years of age hospitalized with acute gastroenteritis in Northern Italy

BACKGROUND

Rotavirus is the major cause of acute gastroenteritis and severe dehydrating diarrhea in young children.

METHODS

To estimate the proportion of hospital admissions for rotavirus acute gastroenteritis and identify the circulating G and P genotypes among children under five years of age, we conducted a prospective observational study from January to December 2008, recruiting children consecutively admitted to six hospitals in Milan and nearby towns in northern Italy. Typing was done on stool samples by reverse transcriptase polymerase chain reaction amplification.

RESULTS

Of the 521 stool samples from children with acute gastroenteritis, 34.9% (95%CI, 30.8 to 39.2%) were rotavirus-positive. Two thirds (67.6%) were under two years of age, and 13.2% were under six months. The predominant G type was G1 (40.7%), followed by G9 (22.5%), G2 (13.2%), G3 (5.5%), G4 (3.8%) and G10 (1.6%). Twenty-one (11.7%) mixed-G infections were identified: G1+G10 (8.8%); G1+G9 (1.6%); and G2+G10 (1.2%). Only P[8] (67.6%) and P[4] (12.6%) types were P genotyped. The predominant single G/P combination was G1P[8] (39.7%), followed by G9P[8] (25.3%), G2P[4] (14.3%), and G3P[8] (4.1%). All G-mixed types combined with P[8].

CONCLUSIONS

These findings show an high prevalence of rotavirus infections among children admitted to hospital for acute gastroenteritis caused by different rotavirus strains circulating in the area studied.

Bile tolerant Lactobacillus reuteri isolated from pig feces inhibits enteric bacterial pathogens and porcine rotavirus

Lactic acid producing bacterial strain Probio-16 was isolated from the swine excrements under anaerobic conditions and characterized by morphology and biochemical characteristics. The strain was further identified by 16S rRNA gene sequencing and phylogeneitc analysis. The antimicrobial activity of the strain was assayed by testing for growth inhibition of thirteen pathogenic microorganisms. The strain was tested for antiviral activity against porcine rotavirus in vitro in African green monkey epithelial cell line TF-104. Antibiotic susceptibility of the strain against 13 antibiotics was tested using disk diffusion method. Phenotypically and through 16S rRNA gene sequences, Probio-16 was identified and named as Lactobacillus reuteri Probio-16. This strain was resistant to pH 2.0, 5% porcine bile and exhibited antimicrobial activity against all the thirteen enteric bacterial pathogens tested. Probio-16 supernatant inhibited porcine rotavirus in vitro in TF-104 cell lines. Except for erythromycin and penicillin G at a concentration of 4 microg/ml, Probio-16 showed resistance to all other thirteen antibiotics tested. This study indicates L. reuteri Probio-16 as a novel strain with its tolerance to low pH and bile, antimicrobial activity, antibiotic resistance and antiviral activity against rotavirus, and an ideal probiotic candidate for animal and human application after the proper in vivo experiments.

Rotavirus gastroenteritis in Norway: analysis of prospective surveillance and hospital registry data

We aimed to evaluate rotavirus morbidity and describe rotavirus epidemiology in hospitalized children in Norway to provide information before the introduction of new rotavirus vaccines. We retrospectively reviewed 14,973 gastroenteritis hospitalizations in children aged <5 y for the period 1995 to 2004, and prospectively surveyed for rotavirus in 311 children aged <5 y admitted with diarrhoea to 3 hospitals in 2006-2008. The proportion of rotavirus among all gastroenteritis hospitalizations was estimated at 14.5% from the retrospective data and at 62.9% in the prospective data. The annual incidence of rotavirus hospitalizations is estimated to be 3 per 1000 children <5 y of age, corresponding to approximately 900 (range 735-1092) hospitalizations each year. Children aged 6-23 months accounted for 61% of all confirmed rotavirus cases, and average duration of hospital stay for rotavirus cases was 1.3 days. We observed a predominance of rotavirus infections from March through May, similar to the seasonality of diarrhoea-associated hospitalizations with viral and unspecified aetiology. No rotavirus-associated deaths were reported. It is estimated that two thirds of all gastroenteritis hospitalizations in children <5 y of age may be attributable to rotavirus in Norway. Continued surveillance and further studies are needed to assess the full burden of rotavirus disease and its economic impact in Norway.

Update on Rotarix: an oral human rotavirus vaccine

Worldwide, rotaviruses are the single most important agents of severe gastroenteritis in infants and young children. Globally, it is estimated that every year rotavirus gastroenteritis causes more than 125 million episodes of diarrhea and nearly 527,000 deaths, mainly in developing countries. The development of new effective and safe rotavirus vaccines was recognized as the most effective intervention strategy that could yield a significant impact on the burden of rotavirus disease. Rotarix is an oral live-attenuated human rotavirus vaccine containing a single G1P[8] strain. The first oral dose may be administered as early as 6 weeks of age, with a minimum interval of 4 weeks prior to second dose; the vaccination course should be completed by the age of 24 weeks according to the manufacturer. In the USA, the upper age limit for the second dose has recently been recommended at 32 weeks of age by the Advisory Committee on Immunization Practices. The development program for Rotarix including Phase I, II and III multicenter studies involving over 100,000 infants has been established in Latin America, Europe, Asia and Africa. The vaccine proved to be well tolerated, immunogenic, efficacious, safe and not associated with intussusception. It provided 85-96% protection against severe rotavirus gastroenteritis caused by G1 and non-G1 serotypes in Latin American and European clinical trials; and of public health importance, Rotarix reduced hospitalizations of all-cause gastroenteritis by 40 and 75%, respectively. Efficacy against G2P[4] strains ranged from 41% in Latin America to 81% in Europe. In the former, Rotarix afforded sustained high protection (80.5%; 95% CI: 71.3-87.1) against severe rotavirus gastroenteritis during the first 2 years of life in a region with a changing pattern of wild-type rotavirus circulation. In a recently completed vaccine trial in South Africa and Malawi, Rotarix showed an overall efficacy of 61.2% (95% CI: 44.0-73.2) by 1 year of age. Although these rates are lower than those from developed and middle-income countries, they look promising given the lack of other effective interventions. With the expanding introduction of rotavirus vaccines into national immunization programs, postmarketing surveillance should be conducted to measure the impact of rotavirus vaccination, as well as continued monitoring of circulating rotavirus strains.

Effectiveness of pentavalent rotavirus vaccine in a large urban population in the United States

OBJECTIVE

The goal was to assess the effectiveness of complete (3-dose) or partial (1- or 2-dose) immunization with pentavalent rotavirus vaccine (RV5) against rotavirus acute gastroenteritis (AGE) in US clinical practice.

METHODS

A case-control evaluation was conducted in February through June 2008 at an emergency department in Houston, Texas. Case patients with rotavirus AGE (N = 90) were identified through testing for rotavirus in fecal specimens obtained from 205 children 15 days through 23 months of age presenting with AGE. Control groups included rotavirus-negative AGE patients (N = 115), concurrently enrolled patients with acute respiratory infection (ARI) (N = 228), and up to 10 age- and zip code-matched children sampled from the Houston-Harris County Immunization Registry (HHCIR) for each case patient >8 months of age. Immunization data were obtained from parent records, health care providers, and/or the HHCIR. Vaccine effectiveness was calculated as 1 minus odds of RV5 vaccination for case patients versus control patients, after adjustment for age at presentation and birth date.

RESULTS

The vaccine effectiveness of a complete RV5 series was 89% (95% confidence interval [CI]: 70%-96%) and 85% (95% CI: 55%-95%) with rotavirus-negative AGE and ARI control patients, respectively. Immunization data were available for 44% of case patients (n = 40) from the HHCIR; the estimated 3-dose vaccine effectiveness with these HHCIR control patients was 82% (95% CI: 19%-96%). A complete RV5 series conferred 100% protection (95% CI: 71%-100%) against severe rotavirus disease requiring hospitalization and 96% protection (95% CI: 72%-99%) against disease requiring intravenous hydration. Vaccine effectiveness of 1 and 2 doses against hospitalization and emergency department visits was 69% (95% CI: 13%-89%) and 81% (95% CI: 13%-96%), respectively, using rotavirus-negative AGE and ARI control groups combined.

CONCLUSIONS

In this setting, a complete series of RV5 was highly effective against severe rotavirus AGE. Partial immunization also conferred substantial protection.

Burden of childhood rotavirus disease on health systems in the United States

BACKGROUND

To determine the burden of rotavirus disease before the introduction of rotavirus vaccines.

METHODS

From February 2005 to June 2006, prospective rotavirus surveillance was conducted in Cincinnati, Ohio, and Durham, North Carolina. Children < 5 years of age presenting at hospitals and outpatient clinics with acute gastroenteritis (AGE) of < 72 hours duration were enrolled. Stool samples were first tested for rotavirus by EIA and the VP7 type was determined by RT-polymerase chain reaction for rotavirus-positive samples. Medical costs were obtained from billing or accounting data.

RESULTS

A total of 1998 children were enrolled, with a mean age of 16.9 months. Among 1601 (80%) patients with a stool specimen, 44% were rotavirus positive. The rotavirus detection rate was 38% for patients admitted to hospital, 60% for patients requiring a short-stay hospital visit (< 24 hour hospitalization), 49% for emergency department visits, and 37% for outpatient visits. During the rotavirus season, rotavirus accounted for 56% of all AGE cases. Only 11% of rotavirus-positive children were assigned the rotavirus-specific ICD-9-CM code and this proportion varied considerably by clinical setting. The VP7 genotypes identified were G1, 79%; G2, 14%; G3, 5%; G9, 1%; and G12, 1%. For children hospitalized with rotavirus, the estimated median direct cost was $4565, the average length of stay was 1.9 days, and parents lost 3.4 days of work. For short-stay, emergency department, and outpatient visits, the estimated median costs were $3160, $867, and $75, respectively.

CONCLUSIONS

Before the widespread use of rotavirus vaccines in the United States, rotavirus was prevalent among children treated in hospital-based and outpatient settings and was associated with a substantial proportion of pediatric medical visits for AGE.

Estimated burden of rotavirus-associated diarrhea in ambulatory settings in the United States

BACKGROUND

Two vaccines to prevent disease from rotavirus among young children were recently approved in the United States. Although previous studies of the burden of rotaviral disease have focused on hospitalizations, the assessment of baseline disease burden in ambulatory settings is useful for evaluating the overall impact of the vaccine.

METHODS

Outpatient and emergency department (ED) data for 1994-2006 were analyzed from 2 nationally representative databases: the National Ambulatory Medical Care Survey and the National Hospital Medical Care Survey. Visits by children (younger than 5 years) with acute gastroenteritis (AGE) were identified by using a defined set of International Classification of Diseases, Ninth Revision, Clinical Modification codes. Two previously described methods (the winter-residual-excess [WRE] and Brandt methods) were used to estimate the proportion of AGE attributable to rotavirus and to determine the annual number of visits, annual average visits, and annual visit rates in each setting.

RESULTS

The estimated average annual number of rotavirus-associated visits over the 13-year period was 782 453 outpatient visits and 164 261 ED visits from the WRE method and 665 773 outpatient visits and 205 206 ED visits from the Brandt method. This resulted in an average of 39.1 and 33.3 outpatient visits per 1000 children and 8.2 and 10.3 ED visits per 1000 children for both the WRE and Brandt methods, respectively. The average annual proportion of visits for AGE attributed to rotavirus was 34.2% (29.1% from the Brandt method) in the outpatient setting and 21.8% (27.1% from the Brandt method) in the ED, with wide variations in individual years.

CONCLUSIONS

Before the rotavirus vaccine, rotavirus seemed to be associated with a large number of outpatient and ED visits among young children. Rotavirus vaccine has the potential to reduce many outpatient and ED visits.

Rotavirus gastroenteritis: precursor of functional gastrointestinal disorders?

BACKGROUND AND AIMS

: Abdominal pain-related functional gastrointestinal disorders (AP-FGIDs) following bacterial acute gastroenteritis (AGE) have been demonstrated in adults and children. An adult study demonstrated AP-FGIDs resulting from an outbreak of viral AGE. Viral AGEs are common in children. Thus, the demonstration of AP-FGIDs occurring after a viral infection in children could constitute a significant finding. The aim of the study was to investigate the development of FGIDs following an episode of acute rotavirus gastroenteritis in children. This is the first pediatric multicenter study designed to assess postviral AP-FGIDs.

PATIENTS AND METHODS

: It is a cohort study. Inclusion criteria of the study are children ages 4 to 18 years with history of AGE secondary to rotavirus. Sample size is 44 exposed and 44 controls (unidirectional alpha of 0.05, power of 0.80). Children consulting at 2 hospitals (Chicago, IL, and Naples, Italy) for AGE (2002-2004) who tested positive for rotavirus were randomly contacted by telephone >2 years after the episode. Each exposed child who visited the emergency department or outpatient site for acute trauma or well-child visit within 4 weeks of the index case was matched with a control of the same age and sex. Gastrointestinal symptoms and disability were evaluated with a validated pediatric questionnaire.

RESULTS

: Eighty-eight patients (46 boys, mean age 5.3 years) were recruited. Contacted patients presented with AGE in 2002 (9), 2003 (11), and 2004 (24). Seven (16%) exposed patients and 3 (7%) controls reported AP-FGIDs (P = 0.31).

CONCLUSIONS

: Our study suggests that rotavirus infection does not seem to place children at increased risk for AP-FGIDs at long-term follow-up. Larger, prospective studies should be conducted to evaluate whether rotavirus gastroenteritis leads to AP-FGIDs in children.

Rotavirus infection and intussusception in Tunisian children: implications for use of attenuated rotavirus vaccines

BACKGROUND

A licensed rotavirus vaccine was withdrawn from use because of an increased risk of intussusception. The association of rotavirus vaccination with intussusception raised concerns about a potential link between natural rotavirus disease and intussusception. The objectives of the present study were to determine whether an epidemiological association with natural rotavirus infection existed.

METHODS

From 1984 to 2003, all children younger than 5 years with intussusception were retrospectively identified by medical charts, and from 1995 to 2003, a prospective surveillance study of rotavirus infection in children younger than 5 years was independently conducted. Epidemiological characteristics of intussusception and rotavirus infection were then compared.

RESULTS

A total of 533 cases of intussusception and 146 cases of rotavirus infection were identified. The incidence of intussusception for infants younger than 1 year was 62/100,000 child-years. The age distributions of intussusception and rotavirus gastroenteritis overlapped, and a masculine predominance was noted in both cases. No significant association was observed between the monthly distribution of intussusception and rotavirus infection.

CONCLUSION

The present study has not convincingly shown that rotavirus diarrhea plays a major role in intussusception. However, data about age and sex distributions supported the biologic plausibility of such an association.

The burden of rotavirus hospitalizations among Medicaid and non-Medicaid children younger than 5 years old

OBJECTIVES

We sought to compare the burden of hospitalizations associated with rotavirus gastroenteritis (RGE) in children younger than 5 years in US Medicaid and non-Medicaid populations in 2000 and 2003.

METHODS

We used the Kids' Inpatient Database (KID) to examine the burden of RGE-associated hospitalizations in terms of numbers and rates of hospitalizations, lengths of stay, and hospital charges. Two indirect methods were also used to estimate RGE-associated hospitalizations, because rotavirus testing is not routinely performed.

RESULTS

Approximately 40% of children younger than 5 years were enrolled in Medicaid in 2003, but this population accounted for nearly 50% of all RGE-associated hospitalizations and 60% of total charges. Children enrolled in Medicaid had significantly greater hospitalization rates, average lengths of stay, and average charges per stay than did those not enrolled.

CONCLUSIONS

Although RGE affects all socioeconomic groups, the Medicaid population accounted for a disproportionate number of the hospitalizations. With the inclusion of rotavirus vaccines in the pediatric immunization schedule, it is important that US children, especially those enrolled in Medicaid programs, are vaccinated to reduce the burden of RGE.

Cost of routine immunization of young children against rotavirus infection with Rotarix versus RotaTeq

Using a probabilistic model of the clinical and economic burden of rotavirus gastroenteritis (RVGE), we estimated the expected impact of vaccinating a US birth cohort with Rotarix in lieu of RotaTeq. Assuming full vaccination of all children, use of Rotarix - rather than RotaTeq - was estimated to reduce the total number of RVGE events by 5% and associated costs by 8%. On an overall basis, Rotarix would reduce costs by $77.2 million (95% CI $71.5-$86.5). Similar reductions with Rotarix were estimated to occur under an assumption of incomplete immunization of children.

Rotavirus overview

Rotaviral gastroenteritis is a serious public health problem in both developed and developing countries. The disease is ubiquitous, affecting nearly all children by the age of 5 years. It is the most common cause of hospitalizations for gastroenteritis among children in the United States (30%-70% depending on the season) and is associated with direct and indirect costs of approximately $1 billion per year. Symptoms of rotaviral gastroenteritis are nonspecific (ie, diarrhea, vomiting, and fever), with disease severity varying considerably. Diagnostic confirmation of rotaviral gastroenteritis requires laboratory tests (most commonly enzyme immunoassay or latex agglutination); however, because specific diagnosis is costly and does not affect treatment, laboratory tests are generally not performed. Because no antiviral therapies are currently available, treatment of rotavirus infection is supportive and primarily aimed at the replacement of fluid and electrolyte losses. Based on the observations that improved sanitation does not decrease disease prevalence and that hospitalizations remain high despite the availability and use of oral rehydrating solutions, the primary public health intervention for rotavirus infection is vaccination. Current vaccines (ie, RotaTeq, Merck and Company; Rotarix, GlaxoSmithKline) are effective for reducing rotaviral gastroenteritis (particularly severe disease), emergency department visits, and hospitalizations. Rotavirus vaccination is now included as part of the routine vaccination schedule for all infants in the United States.

Burden of acute gastroenteritis hospitalizations and emergency department visits in US children that is potentially preventable by rotavirus vaccination: a probe study using the now-withdrawn rotashield vaccine

BACKGROUND

With the implementation of a new rotavirus immunization program in the United States in 2006, determining the potential health benefits of rotavirus vaccination is important. We estimated the burden of acute gastroenteritis hospitalizations and emergency department visits in US children that are potentially preventable by rotavirus vaccination.

METHODS

We conducted a retrospective cohort analysis of children who in 1998-1999 were eligible to receive a now-withdrawn rotavirus vaccine (RotaShield) and were continuously enrolled in 1 of 6 managed care organizations in the Vaccine Safety Datalink. Estimates of vaccine effectiveness against all-cause gastroenteritis hospitalizations and emergency department visits adjusted according to month of birth, gender, and managed care organizations were calculated as 1 minus the risk ratio of outcomes among children in different dose groups. The burden of acute gastroenteritis prevented by vaccination was compared with the rotavirus burden estimated by 2 previously used indirect methods.

RESULTS

The effectiveness of a full 3-dose RotaShield series over a 1-year follow-up period was 83% against all-cause gastroenteritis hospitalizations and 43% against all-cause gastroenteritis emergency department visits. An increasing number of doses improved the effectiveness in preventing gastroenteritis hospitalizations, but no clear trend was observed between number of doses and effectiveness in prevention of gastroenteritis emergency department visits. The proportion of gastroenteritis hospitalizations and emergency department visits prevented by vaccination was substantially greater than the 48% to 53% of year-round hospitalizations and 33% of emergency department visits estimated to result from rotavirus by indirect methods.

CONCLUSIONS

The withdrawn rotavirus vaccine was highly effective in preventing hospitalizations and emergency department visits for all-cause acute gastroenteritis and the health benefits of vaccination against rotavirus may be greater than previously estimated.

Viral contaminants of molluscan shellfish: detection and characterisation

Environmental virology started with the detection of poliovirus in water. Since then other enteric viruses responsible for gastroenteritis and hepatitis have replaced enteroviruses as the main target for detection. Most shellfish-borne viral outbreaks are restricted to norovirus and hepatitis A virus, making them the main targets for bivalve virological analysis. The inclusion of virus analysis in regulatory standards for viruses in molluscan bivalve samples must overcome several shortcomings such as the technical difficulties and high costs of virus monitoring, the lack of harmonised and standardised assays and the challenge posed by the ever-changing nature of viruses. Nowadays methods are available to detect, quantify and characterise viral pathogens in molluscan shellfish to reduce the risks of shellfish-borne virus diseases.

Active, population-based surveillance for severe rotavirus gastroenteritis in children in the United States

OBJECTIVES

Routine vaccination of US infants against rotavirus was implemented in 2006, prompting the Centers for Disease Control and Prevention New Vaccine Surveillance Network to begin population-based acute gastroenteritis surveillance among US children<3 years of age. This surveillance system establishes baseline estimates of rotavirus disease burden and allows for the prospective monitoring of rotavirus vaccination impact.

METHODS

Eligible children with acute gastroenteritis (>or=3 episodes of diarrhea and/or any vomiting in a 24-hour period) who were hospitalized, were seen in emergency departments, or visited selected outpatient clinics in 3 US counties during the period of January through June 2006 were enrolled. Epidemiological and clinical information was obtained through parental interview and medical chart review, and stool specimens were tested for rotavirus with enzyme immunoassays. Rotavirus-positive specimens were genotyped by using reverse transcription-polymerase chain reaction assays.

RESULTS

Stool specimens were collected from 516 of the 739 enrolled children with acute gastroenteritis (181 inpatient, 201 emergency department, and 134 outpatient) and 44% tested positive for rotavirus (227 of 516 specimens). The most common strain was P[8]G1 (84%), followed by P[4]G2 (5%) and P[6]G12 (4%). None of the 516 children had received rotavirus vaccine. The rotavirus detection rate was 50% for hospitalized acute gastroenteritis cases, 50% for emergency department visits, and 27% for outpatient visits. Rotavirus-related acute gastroenteritis cases were more likely than non-rotavirus-related acute gastroenteritis cases to present with vomiting, diarrhea, fever, and lethargy. Directly calculated, population-based rates for rotavirus hospitalizations and emergency department visits were 22.5 hospitalizations and 301.0 emergency department visits per 10 000 children<3 years of age, respectively. A sentinel outpatient clinic visit rate of 311.9 outpatient visits per 10,000 children<3 years of age was observed.

CONCLUSIONS

Population-based, laboratory-confirmed rotavirus surveillance in the final rotavirus season before implementation of the US rotavirus vaccine program indicated a considerable burden of disease on the US health care system.

Burden of rotavirus disease among children visiting pediatric emergency departments in Cincinnati, Ohio, and Oakland, California, in 1999-2000

OBJECTIVE

We assessed the incidence of rotavirus disease requiring an emergency department visit among children <5 years of age.

METHODS

We conducted active surveillance for acute gastroenteritis in pediatric emergency departments in Cincinnati, Ohio, and Oakland, California, from March 1999 to May 2000, among children 2 weeks to 59 months of age with acute diarrhea and/or vomiting. We obtained clinical and demographic information from participants and tested their stool specimens for rotavirus.

RESULTS

Approximately 9% of all emergency department visits at the study sites were attributable to acute gastroenteritis. A total of 1433 children were eligible at the 2 sites; 85% were enrolled and 68% provided a stool specimen. Overall, rotavirus was detected in specimens from 27% of children (30% in Cincinnati and 24% in Oakland). Rotavirus detection was higher in bulk stools, compared with rectal swabs, at both Cincinnati (37% vs 23%) and Oakland (46% vs 18%). Patients with rotavirus had more-severe disease than did those with nonrotavirus gastroenteritis. We estimated that the mean annual incidence of emergency department visits attributable to rotavirus was 12 cases per 1000 children in Cincinnati and 15 cases per 1000 children in Oakland. Through extrapolation, we estimated that rotavirus infection causes approximately 260,910 emergency department visits per year among US children.

CONCLUSION

Active surveillance demonstrated that the burden of laboratory-confirmed rotavirus disease treated in emergency department settings among US children is substantial and greater than estimated previously.