Seasonality, Clinical Characteristics, and Outcomes of Respiratory Syncytial Virus Disease by Subtype Among Children Aged <5 Years: New Vaccine Surveillance Network, United States, 2016-2020

BACKGROUND

Respiratory syncytial virus (RSV) is a leading cause of acute respiratory illnesses in children. RSV can be broadly categorized into 2 major subtypes: A and B. RSV subtypes have been known to cocirculate with variability in different regions of the world. Clinical associations with viral subtype have been studied among children with conflicting findings such that no conclusive relationships between RSV subtype and severity have been established.

METHODS

During 2016-2020, children aged <5 years were enrolled in prospective surveillance in the emergency department or inpatient settings at 7 US pediatric medical centers. Surveillance data collection included parent/guardian interviews, chart reviews, and collection of midturbinate nasal plus/minus throat swabs for RSV (RSV-A, RSV-B, and untyped) using reverse transcription polymerase chain reaction.

RESULTS

Among 6398 RSV-positive children aged <5 years, 3424 (54%) had subtype RSV-A infections, 2602 (41%) had subtype RSV-B infections, and 272 (5%) were not typed, inconclusive, or mixed infections. In both adjusted and unadjusted analyses, RSV-A-positive children were more likely to be hospitalized, as well as when restricted to <1 year. By season, RSV-A and RSV-B cocirculated in varying levels, with 1 subtype dominating proportionally.

CONCLUSIONS

Findings indicate that RSV-A and RSV-B may only be marginally clinically distinguishable, but both subtypes are associated with medically attended illness in children aged <5 years. Furthermore, circulation of RSV subtypes varies substantially each year, seasonally and geographically. With introduction of new RSV prevention products, this highlights the importance of continued monitoring of RSV-A and RSV-B subtypes.

Durability of Original Monovalent mRNA Vaccine Effectiveness Against COVID-19 Omicron-Associated Hospitalization in Children and Adolescents - United States, 2021-2023

Pediatric COVID-19 vaccination is effective in preventing COVID-19-related hospitalization, but duration of protection of the original monovalent vaccine during SARS-CoV-2 Omicron predominance merits evaluation, particularly given low coverage with updated COVID-19 vaccines. During December 19, 2021-October 29, 2023, the Overcoming COVID-19 Network evaluated vaccine effectiveness (VE) of ≥2 original monovalent COVID-19 mRNA vaccine doses against COVID-19-related hospitalization and critical illness among U.S. children and adolescents aged 5-18 years, using a case-control design. Too few children and adolescents received bivalent or updated monovalent vaccines to separately evaluate their effectiveness. Most case-patients (persons with a positive SARS-CoV-2 test result) were unvaccinated, despite the high frequency of reported underlying conditions associated with severe COVID-19. VE of the original monovalent vaccine against COVID-19-related hospitalizations was 52% (95% CI = 33%-66%) when the most recent dose was administered <120 days before hospitalization and 19% (95% CI = 2%-32%) if the interval was 120-364 days. VE of the original monovalent vaccine against COVID-19-related hospitalization was 31% (95% CI = 18%-43%) if the last dose was received any time within the previous year. VE against critical COVID-19-related illness, defined as receipt of noninvasive or invasive mechanical ventilation, vasoactive infusions, extracorporeal membrane oxygenation, and illness resulting in death, was 57% (95% CI = 21%-76%) when the most recent dose was received <120 days before hospitalization, 25% (95% CI = -9% to 49%) if it was received 120-364 days before hospitalization, and 38% (95% CI = 15%-55%) if the last dose was received any time within the previous year. VE was similar after excluding children and adolescents with documented immunocompromising conditions. Because of the low frequency of children who received updated COVID-19 vaccines and waning effectiveness of original monovalent doses, these data support CDC recommendations that all children and adolescents receive updated COVID-19 vaccines to protect against severe COVID-19.

Medical Costs of Respiratory Syncytial Virus-Associated Hospitalizations and Emergency Department Visits in Children Aged Younger Than 5 Years: Observational Findings from the New Vaccine Surveillance Network, 2016-2019

OBJECTIVE

To assess medical costs of hospitalizations and emergency department (ED) care associated with respiratory syncytial virus (RSV) disease in children enrolled in the New Vaccine Surveillance Network.

STUDY DESIGN

We used accounting and prospective surveillance data from 6 pediatric health systems to assess direct medical costs from laboratory-confirmed RSV-associated hospitalizations (n = 2007) and ED visits (n = 1267) from 2016 through 2019 among children aged <5 years. We grouped costs into categories relevant to clinical care and administrative billing practices. We examined RSV-associated medical costs by care setting using descriptive and bivariate analyses. We assessed associations between known RSV risk factors and hospitalization costs and length of stay using χ2 tests of association.

RESULTS

The median cost was $7100 (IQR $4006-$13 355) per hospitalized child and $503 (IQR $387-$930) per ED visit. Eighty percent (n = 2628) of our final sample were children aged younger than 2 years. Fewer weeks' gestational age was associated with greater median costs in hospitalized children (P < .001, ≥37 weeks of gestational age: $6840 [$3905-$12 450]; 29-36 weeks of gestational age: $7721 [$4362-$15 274]; <29 weeks of gestational age: $9131 [$4518-$19 924]). Infants born full term accounted for 70% of the total expenditures in our sample. Almost three quarters of the health care dollars spent originated in children younger than 12 months of age, the primary age group targeted by recommended RSV prophylactics.

CONCLUSIONS

Reducing the cost burden for RSV-associated medical care in young children will require prevention of RSV in all young children, not just high-risk infants. Newly available maternal vaccine and immunoprophylaxis products could substantially reduce RSV-associated medical costs.

Factors Associated With Prolonged Respiratory Virus Detection From Polymerase Chain Reaction of Nasal Specimens Collected Longitudinally in Healthy Children in a US Birth Cohort

BACKGROUND

Respiratory viral shedding is incompletely characterized by existing studies due to the lack of longitudinal nasal sampling and limited inclusion of healthy/asymptomatic children. We describe characteristics associated with prolonged virus detection by polymerase chain reaction (PCR) in a community-based birth cohort.

METHODS

Children were followed from birth to 2 years of age in the PREVAIL cohort. Weekly nasal swabs were collected and tested using the Luminex Respiratory Pathogen Panel. Weekly text surveys were administered to ascertain the presence of acute respiratory illnesses defined as fever and/or cough. Maternal reports and medical chart abstractions identified healthcare utilization. Prolonged virus detection was defined as a persistently positive test lasting ≥4 weeks. Factors associated with prolonged virus detection were assessed using mixed effects multivariable logistic regression.

RESULTS

From a sub-cohort of 101 children with ≥70% weekly swabs collected, a total of 1489 viral infections were detected. Prolonged virus detection was found in 23.4% of viral infections overall, 39% of bocavirus infections, 33% of rhinovirus/enterovirus infections, 14% of respiratory syncytial virus (RSV) A infections, and 7% of RSV B infections. No prolonged detection was found for influenza virus A or B, coronavirus 229E or HKU1, and parainfluenza virus 2 or 4 infections. First-lifetime infection with each virus, and co-detection of another respiratory virus were significantly associated with prolonged detection, while symptom status, child sex, and child age were not.

CONCLUSIONS

Prolonged virus detection was observed in 1 in 4 viral infections in this cohort of healthy children and varied by pathogen, occurring most often for bocavirus and rhinovirus/enterovirus. Evaluating the immunological basis of how viral co-detections and recurrent viral infections impact duration of virus detection by PCR is needed to better understand the dynamics of prolonged viral shedding.

Early Estimate of Nirsevimab Effectiveness for Prevention of Respiratory Syncytial Virus-Associated Hospitalization Among Infants Entering Their First Respiratory Syncytial Virus Season - New Vaccine Surveillance Network, October 2023-February 2024

Respiratory syncytial virus (RSV) is the leading cause of hospitalization among infants in the United States. In August 2023, CDC's Advisory Committee on Immunization Practices recommended nirsevimab, a long-acting monoclonal antibody, for infants aged <8 months to protect against RSV-associated lower respiratory tract infection during their first RSV season and for children aged 8-19 months at increased risk for severe RSV disease. In phase 3 clinical trials, nirsevimab efficacy against RSV-associated lower respiratory tract infection with hospitalization was 81% (95% CI = 62%-90%) through 150 days after receipt; post-introduction effectiveness has not been assessed in the United States. In this analysis, the New Vaccine Surveillance Network evaluated nirsevimab effectiveness against RSV-associated hospitalization among infants in their first RSV season during October 1, 2023-February 29, 2024. Among 699 infants hospitalized with acute respiratory illness, 59 (8%) received nirsevimab ≥7 days before symptom onset. Nirsevimab effectiveness was 90% (95% CI = 75%-96%) against RSV-associated hospitalization with a median time from receipt to symptom onset of 45 days (IQR = 19-76 days). The number of infants who received nirsevimab was too low to stratify by duration from receipt; however, nirsevimab effectiveness is expected to decrease with increasing time after receipt because of antibody decay. Although nirsevimab uptake and the interval from receipt of nirsevimab were limited in this analysis, this early estimate supports the current nirsevimab recommendation for the prevention of severe RSV disease in infants. Infants should be protected by maternal RSV vaccination or infant receipt of nirsevimab.

SARS-CoV-2 Epidemiology and COVID-19 mRNA Vaccine Effectiveness Among Infants and Children Aged 6 Months-4 Years - New Vaccine Surveillance Network, United States, July 2022-September 2023

SARS-CoV-2 infection in young children is often mild or asymptomatic; however, some children are at risk for severe disease. Data describing the protective effectiveness of COVID-19 mRNA vaccines against COVID-19-associated emergency department (ED) visits and hospitalization in this population are limited. Data from the New Vaccine Surveillance Network, a prospective population-based surveillance system, were used to estimate vaccine effectiveness using a test-negative, case-control design and describe the epidemiology of SARS-CoV-2 in infants and children aged 6 months-4 years during July 1, 2022-September 30, 2023. Among 7,434 children included, 5% received a positive SARS-CoV-2 test result, and 95% received a negative test result; 86% were unvaccinated, 4% had received 1 dose of any vaccine product, and 10% had received ≥2 doses. When compared with receipt of no vaccines among children, receipt of ≥2 COVID-19 mRNA vaccine doses was 40% effective (95% CI = 8%-60%) in preventing ED visits and hospitalization. These findings support existing recommendations for COVID-19 vaccination of young children to reduce COVID-19-associated ED visits and hospitalization.

Burden of Respiratory Viruses in Children Less Than 2 Years Old in a Community-based Longitudinal US Birth Cohort

BACKGROUND

Respiratory viral infections are a major cause of morbidity and hospitalization in young children. Nevertheless, the population burden of respiratory viral infections, especially asymptomatic cases, is not known due to the lack of prospective community-based cohort studies with intensive monitoring.

METHODS

To address this gap, we enacted the PREVAIL cohort, a Centers for Disease Control and Prevention-sponsored birth cohort in Cincinnati, Ohio, where children were followed from 0 to 2 years of age. Weekly text surveys were administered to record acute respiratory illnesses (ARIs), which were defined as the presence of cough or fever (≥38°C). Weekly midturbinate nasal swabs were collected and tested using the Luminex Respiratory Pathogen Panel, which detected 16 viral pathogens. Viral infection was defined as ≥1 positive tests from the same virus or viral subtype ≤30 days of a previous positive test. Maternal report and medical chart abstractions identified healthcare utilization.

RESULTS

From 4/2017 to 7/2020, 245 mother-infant pairs were recruited and followed. From the 13 781 nasal swabs tested, a total of 2211 viral infections were detected, of which 821 (37%) were symptomatic. Children experienced 9.4 respiratory viral infections/child-year; half were rhinovirus/enterovirus. Viral ARI incidence was 3.3 episodes/child-year. Emergency department visits or hospitalization occurred with only 15% of respiratory syncytial virus infections, 10% of influenza infections, and only 4% of all viral infections. Regardless of pathogen, most infections were asymptomatic or mild.

CONCLUSIONS

Respiratory viral infections are common in children 0-2 years. Most viral infections are asymptomatic or non-medically attended, underscoring the importance of community-based cohort studies.

Infants Admitted to US Intensive Care Units for RSV Infection During the 2022 Seasonal Peak

Importance

Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections (LRTIs) and infant hospitalization worldwide.

Objective

To evaluate the characteristics and outcomes of RSV-related critical illness in US infants during peak 2022 RSV transmission.

Design, Setting, and Participants

This cross-sectional study used a public health prospective surveillance registry in 39 pediatric hospitals across 27 US states. Participants were infants admitted for 24 or more hours between October 17 and December 16, 2022, to a unit providing intensive care due to laboratory-confirmed RSV infection.

Exposure

Respiratory syncytial virus.

Main Outcomes and Measures

Data were captured on demographics, clinical characteristics, signs and symptoms, laboratory values, severity measures, and clinical outcomes, including receipt of noninvasive respiratory support, invasive mechanical ventilation, vasopressors or extracorporeal membrane oxygenation, and death. Mixed-effects multivariable log-binomial regression models were used to assess associations between intubation status and demographic factors, gestational age, and underlying conditions, including hospital as a random effect to account for between-site heterogeneity.

Results

The first 15 to 20 consecutive eligible infants from each site were included for a target sample size of 600. Among the 600 infants, the median (IQR) age was 2.6 (1.4-6.0) months; 361 (60.2%) were male, 169 (28.9%) were born prematurely, and 487 (81.2%) had no underlying medical conditions. Primary reasons for admission included LRTI (594 infants [99.0%]) and apnea or bradycardia (77 infants [12.8%]). Overall, 143 infants (23.8%) received invasive mechanical ventilation (median [IQR], 6.0 [4.0-10.0] days). The highest level of respiratory support for nonintubated infants was high-flow nasal cannula (243 infants [40.5%]), followed by bilevel positive airway pressure (150 infants [25.0%]) and continuous positive airway pressure (52 infants [8.7%]). Infants younger than 3 months, those born prematurely (gestational age <37 weeks), or those publicly insured were at higher risk for intubation. Four infants (0.7%) received extracorporeal membrane oxygenation, and 2 died. The median (IQR) length of hospitalization for survivors was 5 (4-10) days.

Conclusions and Relevance

In this cross-sectional study, most US infants who required intensive care for RSV LRTIs were young, healthy, and born at term. These findings highlight the need for RSV preventive interventions targeting all infants to reduce the burden of severe RSV illness.

Neurological and Psychological Sequelae Associated With Multisystem Inflammatory Syndrome in Children

Importance

Acute neurological involvement occurs in some patients with multisystem inflammatory syndrome in children (MIS-C), but few data report neurological and psychological sequelae, and no investigations include direct assessments of cognitive function 6 to 12 months after discharge.

Objective

To characterize neurological, psychological, and quality of life sequelae after MIS-C.

Design, Setting, and Participants

This cross-sectional cohort study was conducted in the US and Canada. Participants included children with MIS-C diagnosed from November 2020 through November 2021, 6 to 12 months after hospital discharge, and their sibling or community controls, when available. Data analysis was performed from August 2022 to May 2023.

Exposure

Diagnosis of MIS-C.

Main Outcomes and Measures

A central study site remotely administered a onetime neurological examination and in-depth neuropsychological assessment including measures of cognition, behavior, quality of life, and daily function. Generalized estimating equations, accounting for matching, assessed for group differences.

Results

Sixty-four patients with MIS-C (mean [SD] age, 11.5 [3.9] years; 20 girls [31%]) and 44 control participants (mean [SD] age, 12.6 [3.7] years; 20 girls [45%]) were enrolled. The MIS-C group exhibited abnormalities on neurological examination more frequently than controls (15 of 61 children [25%] vs 3 of 43 children [7%]; odds ratio, 4.7; 95% CI, 1.3-16.7). Although the 2 groups performed similarly on most cognitive measures, the MIS-C group scored lower on the National Institutes of Health Cognition Toolbox List Sort Working Memory Test, a measure of executive functioning (mean [SD] scores, 96.1 [14.3] vs 103.1 [10.5]). Parents reported worse psychological outcomes in cases compared with controls, particularly higher scores for depression symptoms (mean [SD] scores, 52.6 [13.1] vs 47.8 [9.4]) and somatization (mean [SD] scores, 55.5 [15.5] vs 47.0 [7.6]). Self-reported (mean [SD] scores, 79.6 [13.1] vs 85.5 [12.3]) and parent-reported (mean [SD] scores, 80.3 [15.5] vs 88.6 [13.0]) quality of life scores were also lower in cases than controls.

Conclusions and Relevance

In this cohort study, compared with contemporaneous sibling or community controls, patients with MIS-C had more abnormal neurologic examinations, worse working memory scores, more somatization and depression symptoms, and lower quality of life 6 to 12 months after hospital discharge. Although these findings need to be confirmed in larger studies, enhanced monitoring may be warranted for early identification and treatment of neurological and psychological symptoms.

Novel paradigm enables accurate monthly gestational screening to prevent congenital toxoplasmosis and more

Background

Congenital toxoplasmosis is a treatable, preventable disease, but untreated causes death, prematurity, loss of sight, cognition and motor function, and substantial costs worldwide.

Methods/Findings

In our ongoing USA feasibility/efficacy clinical trial, data collated with other ongoing and earlier published results proved high performance of an Immunochromatographic-test(ICT) that enables accurate, rapid diagnosis/treatment, establishing new paradigms for care. Overall results from patient blood and/or serum samples tested with ICT compared with gold-standard-predicate-test results found ICT performance for 4606 sera/1876 blood, 99.3%/97.5% sensitive and 98.9%/99.7% specific. However, in the clinical trial the FDA-cleared-predicate test initially caused practical, costly problems due to false-positive-IgM results. For 58 persons, 3/43 seronegative and 2/15 chronically infected persons had false positive IgM predicate tests. This caused substantial anxiety, concerns, and required costly, delayed confirmation in reference centers. Absence of false positive ICT results contributes to solutions: Lyon and Paris France and USA Reference laboratories frequently receive sera with erroneously positive local laboratory IgM results impeding patient care. Therefore, thirty-two such sera referred to Lyon's Reference laboratory were ICT-tested. We collated these with other earlier/ongoing results: 132 of 137 USA or French persons had false positive local laboratory IgM results identified correctly as negative by ICT. Five false positive ICT results in Tunisia and Marseille, France, emphasize need to confirm positive ICT results with Sabin-Feldman-Dye-test or western blot. Separate studies demonstrated high performance in detecting acute infections, meeting FDA, CLIA, WHO ASSURED, CEMark criteria and patient and physician satisfaction with monthly-gestational-ICT-screening.

Conclusions/Significance

This novel paradigm using ICT identifies likely false positives or raises suspicion that a result is truly positive, rapidly needing prompt follow up and treatment. Thus, ICT enables well-accepted gestational screening programs that facilitate rapid treatment saving lives, sight, cognition and motor function. This reduces anxiety, delays, work, and cost at point-of-care and clinical laboratories.

Author’s Summary

Toxoplasmosis is a major health burden for developed and developing countries, causing damage to eyes and brain, loss of life and substantial societal costs. Prompt diagnosis in gestational screening programs enables treatment, thereby relieving suffering, and leading to > 14-fold cost savings for care. Herein, we demonstrate that using an ICT that meets WHO ASSURED-criteria identifying persons with/without antibody to Toxoplasma gondii in sera and whole blood with high sensitivity and specificity, is feasible to use in USA clinical practice. We find this new approach can help to obviate the problem of detection of false positive anti- T.gondii IgM results for those without IgG antibodies to T.gondii when this occurs in present, standard of care, predicate USA FDA cleared available assays. Thus, this accurate test facilitates gestational screening programs and a global initiative to diagnose and thereby prevent and treat T.gondii infection. This minimizes likelihood of false positives (IgG and/or IgM) while maintaining maximum sensitivity. When isolated IgM antibodies are detected, it is necessary to confirm and when indicated continue follow up testing in ∼2 weeks to establish seroconversion. Presence of a positive ICT makes it likely that IgM is truly positive and a negative ICT makes it likely that IgM will be a false positive without infection. These results create a new, enthusiastically-accepted, precise paradigm for rapid diagnosis and validation of results with a second-line test. This helps eliminate alarm and anxiety about false-positive results, while expediting needed treatment for true positive results and providing back up distinguishing false positive tests.

Sustained Within-season Vaccine Effectiveness Against Influenza-associated Hospitalization in Children: Evidence From the New Vaccine Surveillance Network, 2015-2016 Through 2019-2020

BACKGROUND

Adult studies have demonstrated within-season declines in influenza vaccine effectiveness (VE); data in children are limited.

METHODS

We conducted a prospective, test-negative study of children 6 months through 17 years hospitalized with acute respiratory illness at 7 pediatric medical centers during the 2015-2016 through 2019-2020 influenza seasons. Case-patients were children with an influenza-positive molecular test matched by illness onset to influenza-negative control-patients. We estimated VE [100% × (1 - odds ratio)] by comparing the odds of receipt of ≥1 dose of influenza vaccine ≥14 days before illness onset among influenza-positive children to influenza-negative children. Changes in VE over time between vaccination date and illness onset date were estimated using multivariable logistic regression.

RESULTS

Of 8430 children, 4653 (55%) received ≥1 dose of influenza vaccine. On average, 48% were vaccinated through October and 85% through December each season. Influenza vaccine receipt was lower in case-patients than control-patients (39% vs 57%, P < .001); overall VE against hospitalization was 53% (95% confidence interval [CI]: 46, 60%). Pooling data across 5 seasons, the odds of influenza-associated hospitalization increased 4.2% (-3.2%, 12.2%) per month since vaccination, with an average VE decrease of 1.9% per month (n = 4000, P = .275). Odds of hospitalization increased 2.9% (95% CI: -5.4%, 11.8%) and 9.6% (95% CI: -7.0%, 29.1%) per month in children ≤8 years (n = 3084) and 9-17 years (n = 916), respectively. These findings were not statistically significant.

CONCLUSIONS

We observed minimal, not statistically significant within-season declines in VE. Vaccination following current Advisory Committee on Immunization Practices (ACIP) guidelines for timing of vaccine receipt remains the best strategy for preventing influenza-associated hospitalizations in children.

Respiratory Virus Surveillance Among Children with Acute Respiratory Illnesses - New Vaccine Surveillance Network, United States, 2016-2021

The New Vaccine Surveillance Network (NVSN) is a prospective, active, population-based surveillance platform that enrolls children with acute respiratory illnesses (ARIs) at seven pediatric medical centers. ARIs are caused by respiratory viruses including influenza virus, respiratory syncytial virus (RSV), human metapneumovirus (HMPV), human parainfluenza viruses (HPIVs), and most recently SARS-CoV-2 (the virus that causes COVID-19), which result in morbidity among infants and young children (1-6). NVSN estimates the incidence of pathogen-specific pediatric ARIs and collects clinical data (e.g., underlying medical conditions and vaccination status) to assess risk factors for severe disease and calculate influenza and COVID-19 vaccine effectiveness. Current NVSN inpatient (i.e., hospital) surveillance began in 2015, expanded to emergency departments (EDs) in 2016, and to outpatient clinics in 2018. This report describes demographic characteristics of enrolled children who received care in these settings, and yearly circulation of influenza, RSV, HMPV, HPIV1-3, adenovirus, human rhinovirus and enterovirus (RV/EV),* and SARS-CoV-2 during December 2016-August 2021. Among 90,085 eligible infants, children, and adolescents (children) aged <18 years^† with ARI, 51,441 (57%) were enrolled, nearly 75% of whom were aged <5 years; 43% were hospitalized. Infants aged <1 year accounted for the largest proportion (38%) of those hospitalized. The most common pathogens detected were RV/EV and RSV. Before the emergence of SARS-CoV-2, detected respiratory viruses followed previously described seasonal trends, with annual peaks of influenza and RSV in late fall and winter (7,8). After the emergence of SARS-CoV-2 and implementation of associated pandemic nonpharmaceutical interventions and community mitigation measures, many respiratory viruses circulated at lower-than-expected levels during April 2020-May 2021. Beginning in summer 2021, NVSN detected higher than anticipated enrollment of hospitalized children as well as atypical interseasonal circulation of RSV. Further analyses of NVSN data and continued surveillance are vital in highlighting risk factors for severe disease and health disparities, measuring the effectiveness of vaccines and monoclonal antibody-based prophylactics, and guiding policies to protect young children from pathogens such as SARS-CoV-2, influenza, and RSV.

Cepheid Xpert Xpress Flu/RSV evaluation performed by minimally trained non-laboratory operators in a CLIA-waived environment

The COVID-19 pandemic highlighted the significance of readily available and easily performed viral testing for surveillance during future infectious pandemics. The objectives of this study were: to assess the performance of the Xpert Xpress Flu and/or RSV test, a multiplex PCR assay for detecting influenza A and B virus and respiratory syncytial virus nucleic acids in respiratory tract specimens, relative to the Quidel Lyra Influenza A+B assay and the Prodesse ProFlu+ assay, and the system's ease of use by minimally trained operators. Overall, the Xpert Xpress Flu/RSV test demonstrated a high positive and negative percent agreement with the comparator assays, and was easy to use and interpret results, based on the operators’ feedback. We concluded that the Xpert Xpress Flu/RSV test is sensitive, specific, and easy to use for the diagnosis of influenza and RSV by minimally trained operators and can be a valuable tool in future infectious clusters or pandemics.

Gastrointestinal Microbiome Disruption and Antibiotic-Associated Diarrhea in Children Receiving Antibiotic Therapy for Community-Acquired Pneumonia

Antibiotic-associated diarrhea (AAD) is a common side effect of antibiotics. We examined the gastrointestinal microbiota in children treated with β-lactams for community-acquired pneumonia. Data were from 66 children (n = 198 samples), aged 6-71 months, enrolled in the SCOUT-CAP trial (NCT02891915). AAD was defined as ≥1 day of diarrhea. Stool samples were collected on study days 1, 6-10, and 19-25. Samples were analyzed using 16S ribosomal RNA gene sequencing to identify associations between patient characteristics, microbiota characteristics, and AAD (yes/no). Nineteen (29%) children developed AAD. Microbiota compositional profiles differed between AAD groups (permutational multivariate analysis of variance, P < .03) and across visits (P < .001). Children with higher baseline relative abundances of 2 Bacteroides species were less likely to experience AAD. Higher baseline abundance of Lachnospiraceae and amino acid biosynthesis pathways were associated with AAD. Children in the AAD group experienced prolonged dysbiosis (P < .05). Specific gastrointestinal microbiota profiles are associated with AAD in children.

Understanding Variation in Rotavirus Vaccine Effectiveness Estimates in the United States: The Role of Rotavirus Activity and Diagnostic Misclassification

BACKGROUND

Estimates of rotavirus vaccine effectiveness (VE) in the United States appear higher in years with more rotavirus activity. We hypothesized rotavirus VE is constant over time but appears to vary as a function of temporal variation in local rotavirus cases and/or misclassified diagnoses.

METHODS

We analyzed 6 years of data from eight US surveillance sites on 8- to 59-month olds with acute gastroenteritis symptoms. Children's stool samples were tested via enzyme immunoassay (EIA); rotavirus-positive results were confirmed with molecular testing at the US Centers for Disease Control and Prevention. We defined rotavirus gastroenteritis cases by either positive on-site EIA results alone or positive EIA with Centers for Disease Control and Prevention confirmation. For each case definition, we estimated VE against any rotavirus gastroenteritis, moderate-to-severe disease, and hospitalization using two mixed-effect regression models: the first including year plus a year-vaccination interaction, and the second including the annual percent of rotavirus-positive tests plus a percent positive-vaccination interaction. We used multiple overimputation to bias-adjust for misclassification of cases defined by positive EIA alone.

RESULTS

Estimates of annual rotavirus VE against all outcomes fluctuated temporally, particularly when we defined cases by on-site EIA alone and used a year-vaccination interaction. Use of confirmatory testing to define cases reduced, but did not eliminate, fluctuations. Temporal fluctuations in VE estimates further attenuated when we used a percent positive-vaccination interaction. Fluctuations persisted until bias-adjustment for diagnostic misclassification.

CONCLUSIONS

Both controlling for time-varying rotavirus activity and bias-adjusting for diagnostic misclassification are critical for estimating the most valid annual rotavirus VE.

Pre-pregnancy Obesity Associated With Lower Odds of Meeting Breastfeeding Recommendations When Controlling for Prenatal Intentions

Objectives

The American Academy of Pediatrics (AAP) recommends exclusive breastfeeding (EBF) to 6 months of age, with continued breastfeeding (any BF) for at least 1 year. Maternal obesity has been associated with reduced duration of any and exclusive BF. However, few studies have incorporated degree of obesity or controlled for prenatal BF intentions when comparing BF outcomes. We calculated odds of meeting AAP BF recommendations by pre-pregnancy BMI category while controlling for prenatal BF intentions and demographics in PREVAIL, a CDC-funded birth cohort in Cincinnati, OH.

Methods

Prenatally, enrolled subjects completed a 3rd trimester questionnaire including demographics, pre-pregnancy weight and height, and EBF intention to 6 months. BMI (kg/m2) was categorized as healthy (18.5–24.9), overweight (25–29.9), obesity 1 (30–34.9), or obesity 2+ (≥35). Postnatally, mothers self-reported BF initiation, exclusivity, and duration via quarterly study questionnaires. Logistic regression compared EBF to 6 months and ABF to 1 year across BMI categories among those who initiated BF. All models were adjusted for maternal race, education, income and intention to EBF to 6 months.

Results

Of N = 245 enrolled subjects, the pre-pregnancy maternal obesity prevalence was 41% (n = 100), with 23% (n = 57) meeting Obesity 2 + criteria. There were no significant differences between BMI categories in intention to EBF to 6 months or BF initiation, with high (84–87%) initiation rates. Healthy BMI mothers reported the highest (40%) and mothers with obesity 2 + the lowest (4%), rates of EBF to 6 months (aOR 0.13 (CI 0.02–0.57)). Although only 26% of mothers provided any BF at the 1 year mark, healthy BMI mothers (49%) were more likely to achieve this recommendation than mothers with overweight (13%, aOR 0.11 (CI: 0.04, 0.34)), obesity 1 (16%, aOR 0.11 (CI 0.03, 0.33) and obesity 2+ (10%, aOR 0.15 (CI 0.04, 0.46)).

Conclusions

Despite high BF initiation rates, increasing BMI category was associated with decreasing odds of meeting AAP BF recommendations after adjustment for demographics and prenatal EBF intention in the PREVAIL Cohort. Whether these findings can be explained by physiologic barriers associated with higher BMI merits further attention.

Funding Sources

Centers for Disease Control and Prevention.

Safety of Live Attenuated Influenza Vaccine in Children With Asthma

BACKGROUND AND OBJECTIVES

Asthma is considered a precaution for use of quadrivalent live attenuated influenza vaccine (LAIV4) in persons aged ≥5 years because of concerns for wheezing events. We evaluated the safety of LAIV4 in children with asthma, comparing the proportion of children with asthma exacerbations after LAIV4 or quadrivalent inactivated influenza vaccine (IIV4).

METHODS

We enrolled 151 children with asthma, aged 5 to 17 years, during 2 influenza seasons. Participants were randomly assigned 1:1 to receive IIV4 or LAIV4 and monitored for asthma symptoms, exacerbations, changes in peak expiratory flow rate (PEFR), and changes in the asthma control test for 42 days after vaccination.

RESULTS

We included 142 participants in the per-protocol analysis. Within 42 days postvaccination, 18 of 142 (13%) experienced an asthma exacerbation: 8 of 74 (11%) in the LAIV4 group versus 10 of 68 (15%) in the IIV4 group (LAIV4-IIV4 = -0.0390 [90% confidence interval -0.1453 to 0.0674]), meeting the bounds for noninferiority. When adjusted for asthma severity, LAIV4 remained noninferior to IIV4. There were no significant differences in the frequency of asthma symptoms, change in PEFR, or childhood asthma control test/asthma control test scores in the 14 days postvaccination between LAIV4 and IIV4 recipients. Vaccine reactogenicity was similar between groups, although sore throat (P = .051) and myalgia (P <.001) were more common in the IIV4 group.

CONCLUSIONS

LAIV4 was not associated with increased frequency of asthma exacerbations, an increase in asthma-related symptoms, or a decrease in PEFR compared with IIV4 among children aged 5 to 17 years with asthma.

Lethal Pediatric Cerebral Vasculitis Triggered by Severe Acute Respiratory Syndrome Coronavirus 2

BACKGROUND

We report the clinical, radiological, laboratory, and neuropathological findings in support of the first diagnosis of lethal, small-vessel cerebral vasculitis triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in a pediatric patient.

PATIENT DESCRIPTION

A previously healthy, eight-year-old Hispanic girl presented with subacute left-sided weakness two weeks after a mild febrile illness. SARS-CoV-2 nasopharyngeal swab was positive. Magnetic resonance imaging revealed an enhancing right frontal lobe lesion with significant vasogenic edema. Two brain biopsies of the lesion showed perivascular and intraluminal lymphohistiocytic inflammatory infiltrate consistent with vasculitis. Despite extensive treatment with immunomodulatory therapies targeting primary angiitis of the central nervous system, she experienced neurological decline and died 93 days after presentation. SARS-CoV-2 testing revealed positive serum IgG and positive cerebrospinal fluid IgM. Comprehensive infectious, rheumatologic, hematologic/oncologic, and genetic evaluation did not identify an alternative etiology. Postmortem brain autopsy remained consistent with vasculitis.

CONCLUSION

This is the first pediatric presentation to suggest that SARS-CoV-2 can lead to a fatal, postinfectious, inflammatory small-vessel cerebral vasculitis. Our patient uniquely included supportive cerebrospinal fluid and postmortem tissue analysis. While most children recover from the neurological complications of SARS-CoV-2, we emphasize the potential mortality in a child with no risk factors for severe disease.

154. Circulation of Rhinovirus/Enterovirus Respiratory Infections in Children During 2020-21 in the United States

Background

Sharp declines in influenza and respiratory syncytial virus (RSV) circulation across the U.S. have been described during the pandemic in temporal association with community mitigation for control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We aimed to determine relative frequencies of rhinovirus/enterovirus (RV/EV) and other respiratory viruses in children presenting to emergency departments or hospitalized with acute respiratory illness (ARI) prior to and during the COVID-19 pandemic.

Methods

We conducted a multi-center active prospective ARI surveillance study in children as part of the New Vaccine Surveillance Network (NVSN) from December 2016 through January 2021. Molecular testing for RV/EV, RSV, influenza, and other respiratory viruses [i.e., human metapneumovirus, parainfluenza virus (Types 1-4), and adenovirus] were performed on specimens collected from children enrolled children. Cumulative percent positivity of each virus type during March 2020–January 2021 was compared from March-January in the prior seasons (2017-2018, 2018-2019, 2019-2020) using Pearson’s chi-squared. Data are provisional.

Results

Among 69,403 eligible children, 37,676 (54%) were enrolled and tested for respiratory viruses. The number of both eligible and enrolled children declined in early 2020 (Figure 1), but 4,691 children (52% of eligible) were enrolled and tested during March 2020-January 2021. From March 2020-January 2021, the overall percentage of enrolled children with respiratory testing who had detectable RV/EV was similar compared to the same time period in 2017-2018 and 2019-2020 (Figure 1, Table 1). In contrast, the percent positivity of RSV, influenza, and other respiratory viruses combined declined compared to prior years, (p< 0.001, Figure 1, Table 1).

Figure 1. Percentage of Viral Detection Among Enrolled Children Who Received Respiratory Testing, New Vaccine Surveillance Network (NVSN), United States, December 2016 – January 2021

Table 1. Percent of Respiratory Viruses Circulating in March 2020– January 2021, compared to March-January in Prior Years, New Vaccine Surveillance Network (NVSN), United States, March 2017 – January 2021

Conclusion

During 2020, RV/EV continued to circulate among children receiving care for ARI despite abrupt declines in other respiratory viruses within this population. These findings warrant further studies to understand virologic, behavioral, biological, and/or environmental factors associated with this continued RV/EV circulation.

Disclosures

Jennifer E. Schuster, MD, Merck, Sharpe, and Dohme (Individual(s) Involved: Self): Grant/Research Support Marian G. Michaels, MD, MPH, Viracor (Grant/Research Support, performs assay for research study no financial support) John V. Williams, MD, GlaxoSmithKline (Advisor or Review Panel member, Independent Data Monitoring Committee)Quidel (Advisor or Review Panel member, Scientific Advisory Board) Elizabeth P. Schlaudecker, MD, MPH, Pfizer (Grant/Research Support)Sanofi Pasteur (Advisor or Review Panel member) Christopher J. Harrison, MD, GSK (Grant/Research Support)Merck (Grant/Research Support)Pfizer (Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Janet A. Englund, MD, AstraZeneca (Consultant, Grant/Research Support)GlaxoSmithKline (Research Grant or Support)Meissa Vaccines (Consultant)Pfizer (Research Grant or Support)Sanofi Pasteur (Consultant)Teva Pharmaceuticals (Consultant) Claire Midgley, PhD, Nothing to disclose Natasha B. Halasa, MD, MPH, Genentech (Other Financial or Material Support, I receive an honorarium for lectures - it’s a education grant, supported by genetech)Quidel (Grant/Research Support, Other Financial or Material Support, Donation of supplies/kits)Sanofi (Grant/Research Support, Other Financial or Material Support, HAI/NAI testing) Natasha B. Halasa, MD, MPH, Genentech (Individual(s) Involved: Self): I receive an honorarium for lectures - it’s a education grant, supported by genetech, Other Financial or Material Support, Other Financial or Material Support; Sanofi (Individual(s) Involved: Self): Grant/Research Support, Research Grant or Support

1178. Sustained Vaccine Effectiveness Against Influenza-Associated Hospitalization in Children: Evidence from the New Vaccine Surveillance Network, 2015-2016 Through 2019-2020

Background

Adult studies have demonstrated intra-season declines in influenza vaccine effectiveness (VE) with increasing time since vaccination; however, data in children are limited.

Methods

We conducted a prospective, test-negative study of children ages 6 months through 17 years hospitalized with acute respiratory illness at 7 pediatric medical centers each season in the New Vaccine Surveillance Network during the 2015-2016 through 2019-2020 influenza seasons. Cases were children with an influenza-positive molecular test; controls were influenza-negative children. Controls were matched to cases by illness onset date using 3:1 nearest neighbor matching. We estimated VE [100% x (1 – odds ratio)] by comparing the odds of receipt of ≥ 1 dose of influenza vaccine ≥ 14 days before the onset of illness that resulted in hospitalization among influenza-positive children to influenza-negative children. Changes in VE over time between vaccination date and illness onset date during each season were estimated using multivariable logistic regression models.

Results

Of 8,430 hospitalized children (4,781 [57%] male; median age 2.4 years), 4,653 (55%) received ≥ 1 dose of influenza vaccine. On average, 48% and 85% of children were vaccinated by the end of October and December, respectively. Influenza-positive cases (n=1,000; 12%) were less likely to be vaccinated than influenza-negative controls (39% vs. 61%, p&lt; 0.001) and overall VE against hospitalization was 53% (95% CI: 46%, 60%). Pooling data across 5 seasons, the odds of any influenza-associated hospitalization increased 0.96% (95% CI: -0.76%, 2.71%) per week with a corresponding weekly decrease in VE of 0.45% (p=0.275). Odds of hospitalization with time since vaccination increased 0.66% (95% CI: -0.76%, 2.71%) per week in children ≤ 8 years (n=3,084) and 2.16% (95% CI: -1.68%, 6.15%) per week in children 9-17 years (n=771). No significant differences were observed by virus subtype or lineage.

Figure 1. Declines in influenza VE over time from 2015-2016 through 2019-2020, overall (a) and by age group (b: ≤ 8 years; c: 9-17 years)

Conclusion

We observed minimal intra-season declines in VE against influenza-associated hospitalization in U.S. children. Vaccination following Advisory Committee on Immunization Practices guidelines and current timing of vaccine receipt is the best strategy for prevention of influenza-associated hospitalization in children.

Disclosures

Marian G. Michaels, MD, MPH, Viracor (Grant/Research Support, performs assay for research study no financial support) John V. Williams, MD, GlaxoSmithKline (Advisor or Review Panel member, Independent Data Monitoring Committee)Quidel (Advisor or Review Panel member, Scientific Advisory Board) Elizabeth P. Schlaudecker, MD, MPH, Pfizer (Grant/Research Support)Sanofi Pasteur (Advisor or Review Panel member) Natasha B. Halasa, MD, MPH, Genentech (Other Financial or Material Support, I receive an honorarium for lectures - it’s a education grant, supported by genetech)Quidel (Grant/Research Support, Other Financial or Material Support, Donation of supplies/kits)Sanofi (Grant/Research Support, Other Financial or Material Support, HAI/NAI testing) Natasha B. Halasa, MD, MPH, Genentech (Individual(s) Involved: Self): I receive an honorarium for lectures - it’s a education grant, supported by genetech, Other Financial or Material Support, Other Financial or Material Support; Sanofi (Individual(s) Involved: Self): Grant/Research Support, Research Grant or Support Janet A. Englund, MD, AstraZeneca (Consultant, Grant/Research Support)GlaxoSmithKline (Research Grant or Support)Meissa Vaccines (Consultant)Pfizer (Research Grant or Support)Sanofi Pasteur (Consultant)Teva Pharmaceuticals (Consultant) Christopher J. Harrison, MD, GSK (Grant/Research Support)Merck (Grant/Research Support)Pfizer (Grant/Research Support, Scientific Research Study Investigator, Research Grant or Support) Flor M. Munoz, MD, Biocryst (Scientific Research Study Investigator)Gilead (Scientific Research Study Investigator)Meissa (Other Financial or Material Support, DSMB)Moderna (Scientific Research Study Investigator, Other Financial or Material Support, DSMB)Pfizer (Scientific Research Study Investigator, Other Financial or Material Support, DSMB)Virometix (Other Financial or Material Support, DSMB)

Adverse events associated with weekly short course isoniazid and rifapentine therapy in pediatric patients with latent tuberculosis: A chart and literature review

BACKGROUND

Effective yet safe treatment of latent tuberculosis is important for preventing the spread of tuberculosis and the progression to active disease in pediatric patients. As of 2017, the short course combination regimen of weekly isoniazid and rifapentine (3HP) administered by directly observed therapy (DOT) has replaced 9 months of isoniazid as the standard of treatment for latent tuberculosis in pediatric patients. The literature, limited in size, has established the 3HP regimen's superior safety and adherence.

METHODS

We completed a retrospective chart review (n = 22) of pediatric patients at our institution receiving the 3HP regimen via DOT between 2017 and 2019. Frequencies of selected outcomes were compared to previously published data collected in a literature review.

RESULTS

In this retrospective chart review, pediatric patients ages 2-20 years receiving 3HP with DOT for latent tuberculosis experienced frequent adverse events, more severe adverse events such as anaphylaxis, and higher treatment discontinuation than that which has been previously reported in the literature. Of note, our cohort's race/ethnicity differed from the cohorts described in the literature.

CONCLUSIONS

Our data suggests that the short course combination regimen for pediatric latent tuberculosis patients may have a higher adverse event rate than previously established. Although this sample size is small, this study urges further investigation of more diverse cohorts to better establish the 3HP regimen's safety and tolerability.

Persistence of Maternal Anti-Rotavirus Immunoglobulin G in the Post-Rotavirus Vaccine Era

To assess whether titers of anti-rotavirus immunoglobulin G persist during the post-rotavirus vaccine era, the Pediatric Respiratory and Enteric Virus Acquisition and Immunogenesis Longitudinal (PREVAIL) Cohort analyzed serum samples collected from Cincinnati-area mothers and young infants in 2017-2018. Rotavirus-specific antibodies continue to be transferred from US mothers to their offspring in the post-rotavirus vaccine era, despite dramatic decreases in childhood rotavirus gastroenteritis.

Rotavirus Genotype Trends and Gastrointestinal Pathogen Detection in the United States, 2014-16: Results from the New Vaccine Surveillance Network

BACKGROUND

Following the implementation of rotavirus vaccination in 2006, severe acute gastroenteritis (AGE) due to group A rotavirus (RVA) has substantially declined in USA (US) children. We report the RVA genotype prevalence as well as co-infection data from seven US New Vaccine Surveillance Network (NVSN) sites during three consecutive RVA seasons, 2014-2016.

METHODS

A total of 1041 stool samples that tested positive for RVA by Rotaclone enzyme immunoassay (EIA) were submitted to the Centers for Disease Control and Prevention (CDC) for RVA genotyping and multipathogen testing.

RESULTS

A total of 795 (76%) contained detectable RVA at CDC. Rotavirus disease was highest in children < 3 years of age. Four G types (G1, G2, G9, and G12) accounted for 94.6% of strains while two P types (P[4] and P[8]) accounted 94.7% of the strains. Overall, G12P[8] was the most common genotype detected in all three seasons. Stepwise conditional logistic analysis found year and study site were significant predictors of genotype. Twenty four percent (24%) of RVA-positive specimens contained other AGE pathogens.

CONCLUSIONS

G12P[8] predominated over three seasons, but strain predominance varied by year and study site. Ongoing surveillance provides continuous tracking and monitoring of US genotypes during the post vaccine era.

Comparative genomic analysis of genogroup 1 and genogroup 2 rotaviruses circulating in seven US cities, 2014-2016

For over a decade, the New Vaccine Surveillance Network (NVSN) has conducted active rotavirus (RVA) strain surveillance in the USA. The evolution of RVA in the post-vaccine introduction era and the possible effects of vaccine pressure on contemporary circulating strains in the USA are still under investigation. Here, we report the whole-gene characterization (eleven ORFs) for 157 RVA strains collected at seven NVSN sites during the 2014 through 2016 seasons. The sequenced strains included 52 G1P[8], 47 G12P[8], 18 G9P[8], 24 G2P[4], 5 G3P[6], as well as 7 vaccine strains, a single mixed strain (G9G12P[8]), and 3 less common strains. The majority of the single and mixed strains possessed a Wa-like backbone with consensus genotype constellation of G1/G3/G9/G12-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, while the G2P[4], G3P[6], and G2P[8] strains displayed a DS-1-like genetic backbone with consensus constellation of G2/G3-P[4]/P[6]/P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Two intergenogroup reassortant G1P[8] strains were detected that appear to be progenies of reassortment events between Wa-like G1P[8] and DS-1-like G2P[4] strains. Two Rotarix^® vaccine (RV1) and two RV5 derived (vd) reassortant strains were detected. Phylogenetic and similarity matrices analysis revealed 2-11 sub-genotypic allelic clusters among the genes of Wa- and DS-1-like strains. Most study strains clustered into previously defined alleles. Amino acid (AA) substitutions occurring in the neutralization epitopes of the VP7 and VP4 proteins characterized in this study were mostly neutral in nature, suggesting that these RVA proteins were possibly under strong negative or purifying selection in order to maintain competent and actual functionality, but fourteen radical (AA changes that occur between groups) AA substitutions were noted that may allow RVA strains to gain a selective advantage through immune escape. The tracking of RVA strains at the sub-genotypic allele constellation level will enhance our understanding of RVA evolution under vaccine pressure, help identify possible mechanisms of immune escape, and provide valuable information for formulation of future RVA vaccines.

Continued Evidence of the Impact of Rotavirus Vaccine in Children Less Than 3 Years of Age From the United States New Vaccine Surveillance Network: A Multisite Active Surveillance Program, 2006-2016

BACKGROUND

Since 2006, the New Vaccine Surveillance Network has conducted active, population-based surveillance for acute gastroenteritis (AGE) hospitalizations and emergency department (ED) visits in 3 United States counties. Trends in the epidemiology and disease burden of rotavirus hospitalizations and ED visits were examined from 2006 to 2016.

METHODS

Children < 3 years of age hospitalized or visiting the ED with AGE were enrolled from January 2006 through June 2016. Bulk stool specimens were collected and tested for rotavirus. Rotavirus-associated hospitalization and ED visit rates were calculated annually with 2006-2007 defined as the prevaccine period and 2008-2016 as the postvaccine period. Rotavirus genotype trends were compared over time.

RESULTS

Over 11 seasons, 6954 children with AGE were enrolled and submitted a stool specimen (2187 hospitalized and 4767 in the ED). Comparing pre- and postvaccine periods, the proportion of children with rotavirus dramatically declined for hospitalization (49% vs 10%) and ED visits (49% vs 8%). In the postvaccine era, a biennial pattern of rotavirus rates was observed, with a trend toward an older median age. G1P[8] (63%) was the predominant genotype in the prevaccine period with a significantly lower proportion (7%) in the postvaccine period (P < .001). G2P[4] remained stable (8% to 14%) in both periods, whereas G3P[8] and G12P[8] increased in proportion from pre- to postvaccine periods (1% to 25% and 17% to 40%), respectively.

CONCLUSIONS

The epidemiology and disease burden of rotavirus has been altered by rotavirus vaccination with a biennial disease pattern, sustained low rates of rotavirus in children < 3 years of age, and a shift in the residual genotypes from G1P[8] to other genotypes.

Validation of Acute Gastroenteritis-related International Classification of Diseases, Clinical Modification Codes in Pediatric and Adult US Populations

International Classification of Diseases diagnostic codes are used to estimate acute gastroenteritis (AGE) disease burden. We validated AGE-related codes in pediatric and adult populations using 2 multiregional active surveillance platforms. The sensitivity of AGE codes was similar (54% and 58%) in both populations and increased with addition of vomiting-specific codes.

Evidence for Household Transmission of Rotavirus in the United States, 2011-2016

BACKGROUND

Rotavirus is a leading cause of acute gastroenteritis (AGE) in children and is highly transmissible. In this study, we assessed the presence of AGE in household contacts (HHCs) of pediatric patients with laboratory-confirmed rotavirus.

METHODS

Between December 2011 and June 2016, children aged 14 days to 11 years with AGE were enrolled at 1 of 7 hospitals or emergency departments as part of the New Vaccine Surveillance Network. Parental interviews, medical and vaccination records, and stool specimens were collected at enrollment. Stool was tested for rotavirus by an enzyme immunoassay and confirmed by real-time or conventional reverse transcription-polymerase chain reaction assay or repeated enzyme immunoassay. Follow-up telephone interviews were conducted to assess AGE in HHCs the week after the enrolled child's illness. A mixed-effects multivariate model was used to calculate odds ratios.

RESULTS

Overall, 829 rotavirus-positive subjects and 8858 rotavirus-negative subjects were enrolled. Households of rotavirus-positive subjects were more likely to report AGE illness in ≥1 HHC than were rotavirus-negative households (35% vs 20%, respectively; P < .0001). A total of 466 (16%) HHCs of rotavirus-positive subjects reported AGE illness. Of the 466 ill HHCs, 107 (23%) sought healthcare; 6 (6%) of these encounters resulted in hospitalization. HHCs who were <5 years old (odds ratio, 2.2 [P = .004]) were more likely to report AGE illness than those in other age groups. In addition, 144 households reported out-of-pocket expenses (median, $20; range, $2-$640) necessary to care for an ill HHC.

CONCLUSIONS

Rotavirus-associated AGE in children can lead to significant disease burden in HHCs, especially in children aged <5 years. Prevention of pediatric rotavirus illness, notably through vaccination, can prevent additional illnesses in HHCs.

Association of Rotavirus Vaccination With Inpatient and Emergency Department Visits Among Children Seeking Care for Acute Gastroenteritis, 2010-2016

IMPORTANCE

Rotavirus vaccines have been recommended for universal US infant immunization for more than 10 years, and understanding their effectiveness is key to the continued success of the US rotavirus vaccine immunization program.

OBJECTIVE

To assess the association of RotaTeq (RV5) and Rotarix (RV1) with inpatient and emergency department (ED) visits for rotavirus infection.

DESIGN, SETTING, AND PARTICIPANTS

This case-control vaccine effectiveness study was performed at inpatient and ED clinical settings in 7 US pediatric medical institutions from November 1, 2009, through June 30, 2016. Children younger than 5 years seeking medical care for acute gastroenteritis were enrolled. Clinical and epidemiologic data, vaccination verification, and results of stool sample tests for laboratory-confirmed rotavirus were collected. Data were analyzed from November 1, 2009, through June 30, 2016.

MAIN OUTCOMES AND MEASURES

Rotavirus vaccine effectiveness for preventing rotavirus-associated inpatient and ED visits over time for each licensed vaccine, stratified by clinical severity and age.

RESULTS

Among the 10 813 children included (5927 boys [54.8%] and 4886 girls [45.2%]; median [range] age, 21 [8-59] months), RV5 and RV1 analyses found that compared with controls, rotavirus-positive cases were more often white (RV5, 535 [62.2%] vs 3310 [57.7%]; RV1, 163 [43.1%] vs 864 [35.1%]), privately insured (RV5, 620 [72.1%] vs 4388 [76.5%]; RV1, 305 [80.7%] vs 2140 [87.0%]), and older (median [range] age for RV5, 26 [8-59] months vs 21 [8-59] months; median [range] age for RV1, 22 [8-59] months vs 19 [8-59] months) but did not differ by sex. Among 1193 rotavirus-positive cases and 9620 rotavirus-negative controls, at least 1 dose of any rotavirus vaccine was 82% (95% CI, 77%-86%) protective against rotavirus-associated inpatient visits and 75% (95% CI, 71%-79%) protective against rotavirus-associated ED visits. No statistically significant difference during this 7-year period was observed for either rotavirus vaccine. Vaccine effectiveness against inpatient and ED visits was 81% (95% CI, 78%-84%) for RV5 (3 doses) and 78% (95% CI, 72%-82%) for RV1 (2 doses) among the study population. A mixed course of both vaccines provided 86% (95% CI, 74%-93%) protection. Rotavirus patients who were not vaccinated had severe infections 4 times more often than those who were vaccinated (74 of 426 [17.4%] vs 28 of 605 [4.6%]; P < .001), and any dose of rotavirus vaccine was 65% (95% CI, 56%-73%) effective against mild infections, 81% (95% CI, 76%-84%) against moderate infections, and 91% (95% CI, 85%-95%) against severe infections.

CONCLUSIONS AND RELEVANCE

Evidence from this large postlicensure study of rotavirus vaccine performance in the United States from 2010 to 2016 suggests that RV5 and RV1 rotavirus vaccines continue to perform well, particularly in preventing inpatient visits and severe infections and among younger children.

Factors Associated With Rotavirus Vaccine Coverage

BACKGROUND

Rotavirus vaccines (RVVs) were included in the US immunization program in 2006 and are coadministered with the diphtheria-tetanus-acellular pertussis (DTaP) vaccine, yet their coverage lags behind DTaP. We assessed timing, initiation, and completion of the RVV series among children enrolled in active gastroenteritis surveillance at 7 US medical institutions during 2014-2016.

METHODS

We compared coverage and timing of each vaccine series and analyzed characteristics associated with RVV initiation and completion. We report odds ratios (ORs) and 95% confidence intervals (CIs) from multivariable logistic regression models.

RESULTS

We enrolled 10 603 children. In 2015, ≥1 dose coverage was 91% for RVV and 97% for DTaP. Seven percent of children received their first DTaP vaccine at age ≥15 weeks versus 4% for RVV (P ≤ .001). Recent birth years (2013-2016) were associated with higher odds of RVV initiation (OR = 5.72; 95% CI 4.43-7.39), whereas preterm birth (OR = 0.32; 95% CI 0.24-0.41), older age at DTaP initiation (OR 0.85; 95% CI 0.80-0.91), income between $50 000 and $100 000 (OR = 0.56; 95% CI 0.40-0.78), and higher maternal education (OR = 0.52; 95% CI 0.36-0.74) were associated with lower odds. Once RVV was initiated, recent birth years (2013-2016; OR = 1.57 [95% CI 1.32-1.88]) and higher maternal education (OR = 1.31; 95% CI 1.07-1.60) were associated with higher odds of RVV completion, whereas preterm birth (OR = 0.76; 95% CI 0.62-0.94), African American race (OR = 0.82; 95% CI 0.70-0.97) and public or no insurance (OR = 0.75; 95% CI 0.60-0.93) were associated with lower odds. Regional differences existed.

CONCLUSIONS

RVV coverage remains lower than that for the DTaP vaccine. Timely DTaP administration may help improve RVV coverage.

Laboratory Screening for Children Entering Foster Care

OBJECTIVES

To determine the prevalence of medical illness detected by laboratory screening in children entering foster care in a single, urban county.

METHODS

All children entering foster care in a single county in Ohio were seen at a consultation foster care clinic and had laboratory screening, including testing for infectious diseases such as HIV, hepatitis B, hepatitis C, syphilis, and tuberculosis as well as for hemoglobin and lead levels.

RESULTS

Over a 3-year period (2012-2015), laboratory screening was performed on 1977 subjects entering foster care in a consultative foster care clinic. The prevalence of hepatitis B, hepatitis C, syphilis, and tuberculosis were all found to be <1%. There were no cases of HIV. Seven percent of teenagers entering foster care tested positive for Chlamydia. A secondary finding was that 54% of subjects were hepatitis B surface antibody-negative, indicating an absence of detected immunity to the hepatitis B virus.

CONCLUSIONS

Routine laboratory screening for children entering foster care resulted in a low yield. Targeted, rather than routine, laboratory screening may be a more clinically meaningful approach for children entering foster care.

Risk factors for methicillin-resistant Staphylococcus aureus colonization in the neonatal intensive care unit: A systematic review and meta-analysis

CONTEXT

Methicillin-resistant Staphylococcus aureus (MRSA) causes a significant burden of illness in neonatal intensive care units (NICUs) worldwide. Identifying infants colonized with MRSA has become an important infection control strategy to interrupt nosocomial transmission.

OBJECTIVE

Assess risk factors for MRSA colonization in NICUs via a systematic review and meta-analysis.

DATA SOURCES

MEDLINE, Embase, Web of Science, and The Cochrane Library databases were searched from inception through September 2015.

STUDY SELECTION

Studies reporting risk factors for MRSA colonization using noncolonized controls in subspecialty level III or IV NICUs were included.

DATA EXTRACTION

Two authors independently extracted data on MRSA colonization risk factors, study design, and MRSA screening methodology.

RESULTS

Eleven articles were included in the systematic review, with 10 articles analyzed via meta-analysis. MRSA colonization was associated with gestational age <32 weeks (odds ratio [OR], 2.67; 95% confidence interval [CI], 1.35-5.27; P = .01) and birth weight <1,500 g (OR, 2.63; 95% CI, 1.25-5.55; P = .01). Infant sex (P = .21), race (P = .06), inborn status (P = .09), and delivery type (P = .24) were not significantly associated with colonization.

CONCLUSIONS

Very preterm and very-low birth weight infants were identified as having an increased risk for MRSA colonization on meta-analysis. Multifaceted infection prevention strategies should target these high-risk infants to reduce MRSA colonization rates in NICUs.

Structural language, pragmatic communication, behavior, and social competence in children adopted internationally: A pilot study

The objectives of this study were to examine the association of structural language and pragmatic communication with behavior problems and social competence in girls adopted internationally. Participants included girls between 6-12 years of age who were internationally adopted from China (n = 32) and Eastern-Europe (n = 25) and a control group of never-adopted girls (n = 25). Children completed the Wechsler Abbreviated Scale of Intelligence. Parents completed the Child Communication Checklist- second edition, the Child Behavior Checklist, and the Home and Community Social Behavior Scales. Compared to the controls, parents in the Eastern European group reported more problems with social competence, externalizing behaviors, structural language, and pragmatic communication. The Chinese group evidenced more internalizing problems. Using generalized linear regression, interaction terms were examined to determine if the associations of pragmatic communication and structural language with behavior problems and social competence varied across groups. Controlling for general intellectual functioning, poorer pragmatic communication was associated with more externalizing problems and poorer social competence. In the Chinese group, poorer pragmatic communication was associated with more internalizing problems. Post-adoption weaknesses in pragmatic communication are associated with behavior problems and social competence. Internationally adopted children may benefit from interventions that target pragmatic communication.

Long-term Consistency in Rotavirus Vaccine Protection: RV5 and RV1 Vaccine Effectiveness in US Children, 2012-2013

BACKGROUND

Using a multicenter, active surveillance network from 2 rotavirus seasons (2012 and 2013), we assessed the vaccine effectiveness of RV5 (RotaTeq) and RV1 (Rotarix) rotavirus vaccines in preventing rotavirus gastroenteritis hospitalizations and emergency department (ED) visits for numerous demographic and secular strata.

METHODS

We enrolled children hospitalized or visiting the ED with acute gastroenteritis (AGE) for the 2012 and 2013 seasons at 7 medical institutions. Stool specimens were tested for rotavirus by enzyme immunoassay and genotyped, and rotavirus vaccination histories were compared for rotavirus-positive cases and rotavirus-negative AGE controls. We calculated the vaccine effectiveness (VE) for preventing rotavirus associated hospitalizations and ED visits for each vaccine, stratified by vaccine dose, season, clinical setting, age, predominant genotype, and ethnicity.

RESULTS

RV5-specific VE analyses included 2961 subjects, 402 rotavirus cases (14%) and 2559 rotavirus-negative AGE controls. RV1-specific VE analyses included 904 subjects, 100 rotavirus cases (11%), and 804 rotavirus-negative AGE controls. Over the 2 rotavirus seasons, the VE for a complete 3-dose vaccination with RV5 was 80% (confidence interval [CI], 74%-84%), and VE for a complete 2-dose vaccination with RV1 was 80% (CI, 68%-88%).Statistically significant VE was observed for each year of life for which sufficient data allowed analysis (7 years for RV5 and 3 years for RV1). Both vaccines provided statistically significant genotype-specific protection against predominant circulating rotavirus strains.

CONCLUSIONS

In this large, geographically and demographically diverse sample of US children, we observed that RV5 and RV1 rotavirus vaccines each provided a lasting and broadly heterologous protection against rotavirus gastroenteritis.

Intelligence, Attention, and Behavioral Outcomes in Internationally Adopted Girls with a History of Institutionalization

OBJECTIVE

The aim of this study was to investigate the association of neurocognitive functioning with internalizing and externalizing problems and school and social competence in children adopted internationally.

METHOD

Participants included girls between the ages of 6-12 years who were internationally adopted from China (n = 32) or Eastern Europe (n = 25) and a control group of never-adopted girls (n = 25). Children completed the Vocabulary and Matrix Reasoning subtests from the Wechsler Abbreviated Scale of Intelligence and the Score! and Sky Search subtests from the Test of Everyday Attention for Children. Parents completed the Child Behavior Checklist and the Home and Community Social Behavior Scales.

RESULTS

Compared to the controls, the Eastern European group evidenced significantly more problems with externalizing behaviors and school and social competence and poorer performance on measures of verbal intelligence, perceptual reasoning, and auditory attention. More internalizing problems were reported in the Chinese group compared to the controls. Using generalized linear regression, interaction terms were examined to determine whether the associations of neurocognitive functioning with behavior varied across groups. Eastern European group status was associated with more externalizing problems and poorer school and social competence, irrespective of neurocognitive test performance. In the Chinese group, poorer auditory attention was associated with more problems with social competence.

CONCLUSIONS

Neurocognitive functioning may be related to behavior in children adopted internationally. Knowledge about neurocognitive functioning may further our understanding of the impact of early institutionalization on post-adoption behavior.

Risk Factors Associated With Surgical Site Infection After Pediatric Posterior Spinal Fusion Procedure

Objective.

To identify risk factors associated with surgical site infection (SSI) after pediatric posterior spinal fusion procedure by examining characteristics related to the patient, the surgical procedure, and tissue hypoxia.

Design.

Retrospective case-control study nested in a hospital cohort study.

Setting.

A 475-bed, tertiary care children's hospital.

Methods.

All patients who underwent a spinal fusion procedure during the period from January 1995 through December 2006 were included. SSI cases were identified by means of prospective surveillance using National Nosocomial Infection Surveillance system definitions. Forty-four case patients who underwent a posterior spinal fusion procedure and developed an SSI were identified and evaluated. Each case patient was matched (on the basis of date of surgery, ± 3 months) to 3 control patients who underwent a posterior spinal fusion procedure but did not develop an SSI. Risk factors for SSI were evaluated by univariate analysis and multivariable conditional logistic regression. Odds ratios (ORs), with 95% confidence intervals (CIs) andPvalues, were calculated.

Results.

From 1995 to 2006, the mean annual rate of SSI after posterior spinal fusion procedure was 4.4% (range, 1.1%—6.7%). Significant risk factors associated with SSI in the univariate analysis included the following: a body mass index (BMI) greater than the 95th percentile (OR, 3.5 [95% CI, 1.5–8.3]); antibiotic prophylaxis with clindamycin, compared with other antibiotics (OR, 3.5 [95% CI, 1.2 10.0]); inappropriately low dose of antibiotic (OR, 2.6 [95% CI, 1.0–6.6]); and a longer duration of hypothermia (ie, a core body temperature of less than 35.5°C) during surgery (OR, 0.4 [95% CI, 0.2–0.9]). An American Society of Anesthesiologists (ASA) score of greater than 2, obesity (ie, a BMI greater than the 95th percentile), antibiotic prophylaxis with clindamycin, and hypothermia were statistically significant in the multivariable model.

Conclusion.

An ASA score greater than 2, obesity, and antibiotic prophylaxis with clindamycin were independent risk factors for SSI. Hypothermia during surgery appears to provide protection against SSI in this patient population.

Comparison of 2 assays for diagnosing rotavirus and evaluating vaccine effectiveness in children with gastroenteritis

We compared rotavirus detection rates in children with acute gastroenteritis (AGE) and in healthy controls using enzyme immunoassays (EIAs) and semiquantitative real-time reverse transcription PCR (qRT-PCR). We calculated rotavirus vaccine effectiveness using different laboratory-based case definitions to determine which best identified the proportion of disease that was vaccine preventable. Of 648 AGE patients, 158 (24%) were EIA positive, and 157 were also qRT-PCR positive. An additional 65 (10%) were qRT-PCR positive but EIA negative. Of 500 healthy controls, 1 was EIA positive and 24 (5%) were qRT-PCR positive. Rotavirus vaccine was highly effective (84% [95% CI 71%-91%]) in EIA-positive children but offered no significant protection (14% [95% CI -105% to 64%]) in EIA-negative children for whom virus was detected by qRT-PCR alone. Children with rotavirus detected by qRT-PCR but not by EIA were not protected by vaccination, suggesting that rotavirus detected by qRT-PCR alone might not be causally associated with AGE in all patients.

Prevalence of respiratory syncytial virus-associated lower respiratory infection and apnea in infants presenting to the emergency department

The prevalence of respiratory syncytial virus in children presenting to US emergency departments with lower respiratory tract infection or apnea (N = 4172) was evaluated outside the traditional respiratory syncytial virus season (September to October and April to May) relative to January to February. The Mid-Atlantic and Southeast demonstrated positivity rates in September to October comparable with rates observed during January to February.

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.

Etiology of viral gastroenteritis in children <5 years of age in the United States, 2008-2009

BACKGROUND

Although rotavirus and norovirus cause nearly 40% of severe endemic acute gastroenteritis (AGE) in children <5 years of age in the United States, there are limited data on the etiologic role of other enteric viruses in this age group.

METHODS

We conducted active population-based surveillance in children presenting with AGE to hospitals, emergency departments, and primary care clinics in 3 US counties. Stool specimens from these children and from age-matched healthy controls collected between October 2008 and September 2009 were tested for enteric adenovirus, astrovirus, sapovirus, parechovirus, bocavirus, and aichivirus. Typing was performed by sequencing and phylogenetic analysis.

RESULTS

Adenovirus, astrovirus, sapovirus, parechovirus, bocavirus, and aichivirus were detected in the stool specimens of 11.8%, 4.9%, 5.4%, 4.8%, 1.4%, and 0.2% of patients with AGE and 1.8%, 3.0%, 4.2%, 4.4%, 2.4%, and 0% of healthy controls, respectively. Adenovirus (type 41), astrovirus (types 1, 2, 3, 4, and 8), sapovirus (genogroups I and II), parechovirus (types 1, 3, 4, and 5), and bocavirus (types 1, 2, and 3) were found cocirculating.

CONCLUSIONS

Adenovirus, astrovirus, and sapovirus infections were detected in 22.1% of the specimens from children <5 years of age who had medical visits for AGE and tested negative for rotavirus and norovirus. No causal role for parechovirus and bocavirus was found.

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.

Norovirus and medically attended gastroenteritis in U.S. children

BACKGROUND

Cases of rotavirus-associated acute gastroenteritis have declined since the introduction of rotavirus vaccines, but the burden of norovirus-associated acute gastroenteritis in children remains to be assessed.

METHODS

We conducted active surveillance for laboratory-confirmed cases of norovirus among children younger than 5 years of age with acute gastroenteritis in hospitals, emergency departments, and outpatient clinical settings. The children resided in one of three U.S. counties during the years 2009 and 2010. Fecal specimens were tested for norovirus and rotavirus. We calculated population-based rates of norovirus-associated acute gastroenteritis and reviewed billing records to determine medical costs; these data were extrapolated to the U.S. population of children younger than 5 years of age.

RESULTS

Norovirus was detected in 21% of young children (278 of 1295) seeking medical attention for acute gastroenteritis in 2009 and 2010, with norovirus detected in 22% (165 of 742) in 2009 and 20% (113 of 553) in 2010 (P=0.43). The virus was also detected in 4% of healthy controls (19 of 493) in 2009. Rotavirus was identified in 12% of children with acute gastroenteritis (152 of 1295) in 2009 and 2010. The respective rates of hospitalization, emergency department visits, and outpatient visits for the norovirus were 8.6, 146.7, and 367.7 per 10,000 children younger than 5 years of age in 2009 and 5.8, 134.3, and 260.1 per 10,000 in 2010, with an estimated cost per episode of $3,918, $435, and $151, respectively, in 2009. Nationally, we estimate that the average numbers of annual hospitalizations, emergency department visits, and outpatient visits due to norovirus infection in 2009 and 2010 among U.S. children in this age group exceeded 14,000, 281,000, and 627,000, respectively, with more than $273 million in treatment costs each year.

CONCLUSIONS

Since the introduction of rotavirus vaccines, norovirus has become the leading cause of medically attended acute gastroenteritis in U.S. children and is associated with nearly 1 million health care visits annually. (Funded by the Centers for Disease Control and Prevention.).

Effectiveness of pentavalent and monovalent rotavirus vaccines in concurrent use among US children <5 years of age, 2009-2011

BACKGROUND

We assessed vaccine effectiveness (VE) for RotaTeq (RV5; 3 doses) and Rotarix (RV1; 2 doses) at reducing rotavirus acute gastroenteritis (AGE) inpatient and emergency department (ED) visits in US children.

METHODS

We enrolled children <5 years of age hospitalized or visiting the ED with AGE symptoms from November 2009-June 2010 and from November 2010-June 2011 at 7 medical institutions. Fecal specimens were tested for rotavirus by enzyme immunoassay and genotyped. Vaccination among laboratory-confirmed rotavirus cases was compared with rotavirus-negative AGE controls. Regression models calculated VE estimates for each vaccine, age, ethnicity, genotype, and clinical setting.

RESULTS

RV5-specific analyses included 359 rotavirus cases and 1811 rotavirus-negative AGE controls. RV1-specific analyses included 60 rotavirus cases and 155 rotavirus-negative AGE controls. RV5 and RV1 were 84% (95% confidence interval [CI], 78%-88%) and 70% (95% CI, 39%-86%) effective, respectively, against rotavirus-associated ED visits and hospitalizations combined. By clinical setting, RV5 VE against ED and inpatient rotavirus-associated visits was 81% (95% CI, 70%-84%) and 86% (95% CI, 74%-91%), respectively. RV1 was 78% (95% CI, 46%-91%) effective against ED rotavirus disease; study power was insufficient to evaluate inpatient RV1 VE. No waning of immunity was evident during the first 4 years of life for RV5, nor during the first 2 years of life for RV1. RV5 provided genotype-specific protection against each of the predominant strains (G1P[8], G2P[4], G3P[8], G12P[8]), while RV1 VE was statistically significant for the most common genotype, G3P[8].

CONCLUSIONS

Both RV5 and RV1 significantly protected against medically attended rotavirus gastroenteritis in this real-world assessment.

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.

Low prevalence of Chlamydia trachomatis infection in non-urban pregnant women in Vellore, S. India

Objective

To determine the prevalence and risk factors for Chlamydia trachomatis (CT) infection in pregnant women and the rate of transmission of CT to infants.

Methods

Pregnant women (≥28 weeks gestation) in Vellore, South India were approached for enrollment from April 2009 to January 2010. After informed consent was obtained, women completed a socio-demographic, prenatal, and sexual history questionnaire. Endocervical samples collected at delivery were examined for CT by a rapid enzyme test and nucleic acid amplification test (NAAT). Neonatal nasopharyngeal and conjunctival swabs were collected for NAAT testing.

Results

Overall, 1198 women were enrolled and 799 (67%) endocervical samples were collected at birth. Analyses were completed on 784 participants with available rapid and NAAT results. The mean age of women was 25.8 years (range 18–39 yrs) and 22% (95% CI: 19.7–24.4%) were primigravida. All women enrolled were married; one reported >one sexual partner; and six reported prior STI. We found 71 positive rapid CT tests and 1/784 (0.1%; 95% CI: 0–0.38%) true positive CT infection using NAAT.

Conclusions

To our knowledge, this is the largest study on CT prevalence amongst healthy pregnant mothers in southern India, and it documents a very low prevalence with NAAT. Many false positive results were noted using the rapid test. These data suggest that universal CT screening is not indicated in this population.