Low incidence of respiratory syncytial virus hospitalisations in haemodynamically significant congenital heart disease

Postpandemic fluctuations of regional respiratory syncytial virus hospitalization epidemiology: potential impact on an immunization program in Switzerland

RSV hospitalization epidemiology is subject to rapid changes brought about by the COVID-19 pandemic and the prospect of vaccine prevention. The purpose of this report is to characterize recent epidemiologic and clinical fluctuations and to analyze their potential impact on an immunization program with nirsevimab. This is a 2018-2024 retrospective analysis of all hospitalizations caused by RSV in patients below 16 years of age occurring at an academic Children's Hospital that serves a defined population. We simulated the vaccine impact against RSV hospitalization by applying the expected effects of the infant immunization program with nirsevimab proposed in Switzerland to observed case counts. We analyzed 1339 hospitalizations. The consecutive occurrence of two major epidemics in 2022-2023 and 2023-2024 had never been recorded previously. The 2023-2024 season witnessed a major shift to older age. Only 61% of patients were below 12 months of age, while prepandemic long-term surveillance since 1997 found a range between 64 and 85% (median, 73%). Age below 3 months, prematurity, airway anomalies, congenital heart disease, and neuromuscular disorders were independently associated with ICU admission. Simulation of the vaccine impact using two scenarios of coverage and efficacy (scenario 1, 50% and 62%, respectively; scenario 2, 90% and 90%) and three different age distributions resulted in an infant vaccine impact of 31.0% (scenario 1) and 81.0% (scenario 2), respectively. Vaccine impact for all patients below 16 years ranged from 22.7 to 24.9% (scenario 1) and 54.2 to 68.8% (scenario 2).

CONCLUSION

RSV hospitalization epidemiology was characterized by substantial variability in patient age on admission. As the proposed RSV immunization program primarily targets infants, year-to-year fluctuation of cases among older children will cause a variability of vaccine impact of approximately 15%. This information may be useful for physicians and hospital administrators when they anticipate the resources needed during the winter season.

WHAT IS KNOWN

• RSV hospitalization epidemiology was subject to massive disturbances during the COVID-19 pandemic. • Extended half-life monoclonal antibodies and active maternal immunization offer new means of passive protection of infants against severe RSV disease.

WHAT IS NEW

• We demonstrate substantial year-to-year fluctuation of the age distribution at the time of RSV hospitalization. • Up to 40% of annual RSV hospitalizations in a given season occur in children above 12 months of age who do not benefit from maternal RSV immunization and may not be eligible for receipt of a monoclonal antibody.

Prophylaxis protects infants with congenital heart disease from severe forms of RSV infection: an Italian observational retrospective study : Palivizumab prophylaxis in children with congenital heart disease

BACKGROUND

In children with congenital heart disease (CHD) respiratory syncytial virus (RSV) infection may have a severe course, with increased risk of morbidity and mortality, requiring hospital admission and intensive care. The aim of the present study was to evaluate the effect of prophylaxis with palivizumab in preventing RSV-associated hospitalization in infants with CHD.

METHODS

We carried out an observational, retrospective study in a paediatric cardiology division at a secondary-care centre in Italy, extracting from the database children with CHD who, from November 2004 to March 2022, matched the criteria for palivizumab prophylaxis, to evaluate the hospitalization rate in CHD patients with and without palivizumab prophylaxis and their RSV-related hospitalization characteristics compared with a group of children without CHD and no other underlying clinical conditions (control group, CG), hospitalized for RSV infection.

RESULTS

One hundred twenty-eight children with CHD were enrolled in the study, mainly (71.9%) with increased pulmonary flow, and received palivizumab prophylaxis. Twenty-seven received hospital care for bronchiolitis. Almost all CHD patients hospitalized for bronchiolitis (26 out of 27) received partial prophylaxis (≤ 3 doses). CHD patients with bronchiolitis stay longer in the hospital than control (14.4 ± 21.7 days vs 6.2 ± 2.3 days) some of which require intensive care (n = 4).

CONCLUSIONS

Our study provides evidence of the efficacy of palivizumab in protecting patients with hemodynamically significant CHD under the age of 2 years from RSV disease and its life-threatening complications. Reducing hospitalisation rate, morbidity, and mortality in this category of patients, passive immune prophylaxis with palivizumab may impact healthcare resource availability and utilisation.

Risk factors for hospitalisation in Welsh infants with a congenital anomaly

OBJECTIVES

To investigate risk factor associated with hospitalisation of infants with a congenital anomaly in Wales, UK.

DESIGN

A population-based cohort study.

SETTING

Data from the Welsh Congenital Anomaly Register and Information Service linked to the Patient Episode Database for Wales and livebirths and deaths from the Office for National Statistics.

PATIENTS

All livebirths between 1999 and 2015 with a diagnosis of a congenital anomaly, which was defined as a structural, metabolic, endocrine or genetic defect, as well as rare diseases of hereditary origin.

MAIN OUTCOME MEASURES

Adjusted OR (aOR) associated with 1 or 2+ hospital admissions in infancy versus no admissions were estimated for sociodemographic, maternal and infant factors using multinomial logistic regression for the subgroups of all, isolated, multiple and cardiovascular anomalies.

RESULTS

25 523 infants affected by congenital anomalies experienced a total of 50 705 admissions in infancy. Risk factors for ≥2 admissions were younger maternal age ≤24 years (aOR: 1.17; 95% CI 1.06 to 1.30), maternal smoking (aOR: 1.20; 1.10 to 1.31), preterm birth (aOR: 2.52; 2.25 to 2.83) and moderately severe congenital heart defects (aOR: 6.25; 4.47 to 8.74). Girls had an overall decreased risk of 2+ admissions (aOR: 0.84; 0.78 to 0.91). Preterm birth was a significant risk factor for admissions in all anomaly subgroups but the effect of the other characteristics varied according to anomaly subgroup.

CONCLUSIONS

Over two-thirds of infants with an anomaly are admitted to hospital during infancy. Our findings identified sociodemographic and clinical characteristics contributing to an increased risk of hospitalisation of infants with congenital anomalies.

Respiratory Syncytial Virus-Associated Acute Lower Respiratory Infections in Children With Bronchopulmonary Dysplasia: Systematic Review and Meta-Analysis

BACKGROUND

Respiratory syncytial virus (RSV) is among the most important causes of acute lower respiratory tract infection (ALRI) in young children. We assessed the severity of RSV-ALRI in children less than 5 years old with bronchopulmonary dysplasia (BPD).

METHODS

We searched for studies using EMBASE, Global Health, and MEDLINE. We assessed hospitalization risk, intensive care unit (ICU) admission, need for oxygen supplementation and mechanical ventilation, and in-hospital case fatality (hCFR) among children with BPD compared with those without (non-BPD). We compared the (1) length of hospital stay (LOS) and (2) duration of oxygen supplementation and mechanical ventilation between the groups.

RESULTS

Twenty-nine studies fulfilled our inclusion criteria. The case definition for BPD varied substantially in the included studies. Risks were higher among children with BPD compared with non-BPD: RSV hospitalization (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.7-4.2; P < .001), ICU admission (OR, 2.9; 95% CI, 2.3-3.5; P < .001), need for oxygen supplementation (OR, 4.2; 95% CI, .5-33.7; P = .175) and mechanical ventilation (OR, 8.2; 95% CI, 7.6-8.9; P < .001), and hCFR (OR, 12.8; 95% CI, 9.4-17.3; P < .001). Median LOS (range) was 7.2 days (4-23) (BPD) compared with 2.5 days (1-30) (non-BPD). Median duration of oxygen supplementation (range) was 5.5 days (0-21) (BPD) compared with 2.0 days (0-26) (non-BPD). The duration of mechanical ventilation was more often longer (>6 days) in those with BPD compared with non-BPD (OR, 11.9; 95% CI, 1.4-100; P = .02).

CONCLUSIONS

The risk of severe RSV disease is considerably higher among children with BPD. There is an urgent need to establish standardized BPD case definitions, review the RSV prophylaxis guidelines, and encourage more specific studies on RSV infection in BPD patients, including vaccine development and RSV-specific treatment.

Acute Lower Respiratory Infections Associated With Respiratory Syncytial Virus in Children With Underlying Congenital Heart Disease: Systematic Review and Meta-analysis

BACKGROUND

Respiratory syncytial virus (RSV) is the most common viral pathogen associated with acute lower respiratory infections (ALRIs), with significant childhood morbidity and mortality worldwide. Estimates reporting RSV-associated ALRI (RSV-ALRI) severity in children with congenital heart disease (CHD) are lacking, thus warranting the need to summarize the available data. We identified relevant studies to summarize the findings and conducted a meta-analysis of available data on RSV-associated ALRI hospitalizations in children aged <5 years, comparing those with underlying CHD to those without CHD.

METHODS

We conducted a systematic search of existing relevant literature and identified studies reporting hospitalization of children aged <5 years with RSV-ALRI with underlying or no CHD. We summarized the data and conducted (where possible) a random-effects meta-analysis to compare the 2 groups.

RESULTS

We included 18 studies that met our strict eligibility criteria. The risk of severe RSV-ALRI (odds ratio, 2.2; 95% confidence interval [CI], 1.6-2.8), the rate of hospitalization (incidence rate ratio, 2.8; 95% CI, 1.9-4.1), and the case-fatality ratio (risk ratio [RR], 16.5; 95% CI, 13.7-19.8) associated with RSV-ALRI was higher among children with underlying CHD as compared to those without no CHD. The risk of admission to the intensive care unit (RR, 3.9; 95% CI, 3.4-4.5), need for supplemental oxygen therapy (RR, 3.4; 95% CI, .5-21.1), and need for mechanical ventilation (RR, 4.1; 95% CI, 2.1-8.0) was also higher among children with underlying CHD.

CONCLUSION

This is the most detailed review to show more-severe RSV-ALRI among children aged <5 years with underlying CHD, especially hemodynamically significant underlying CHD, as compared those without CHD, supporting a need for improved RSV prophylactics and treatments that also have efficacy in children older than 1 year.

Respiratory syncytial virus acute respiratory infection-associated hospitalizations in preterm Mexican infants: A cohort study

Background

Respiratory syncytial virus (RSV) is the leading cause of severe acute respiratory infections (ARI) in preterm infants. The incidence of RSV‐associated hospitalizations has not been defined in Mexico.

Objectives

To determine the incidence of ARI‐ and RSV‐associated hospitalizations in preterm infants during the first year of life.

Methods

Prospective cohort study of 294 preterm infants followed up through monthly telephone calls and routine outpatient visits. Hospitalized children were identified through daily visits to pediatric wards of participating hospitals and through telephone calls. Respiratory samples were tested for RSV by RT‐PCR.

Results

Mean gestational age of participating infants was 33 weeks. Ninety‐six infants were diagnosed with bronchopulmonary dysplasia (BPD) and 17 with congenital heart disease (CHD); 11 had both conditions. There were 71 hospitalization episodes in 53 infants. Respiratory samples for RSV detection were available in 44 hospitalization episodes, and the result was positive in 16 (36.3%). At least one hospitalization for ARI was recorded in 33 of 96 participants with BPD, in seven of 17 with CHD, and 18 of 192 infants without these diagnoses. Five (71.4%) of CHD infants who required admission also had BPD. RSV‐confirmed hospitalization rates were 9.4%, 5.9%, and 2.6% for infants with BPD, CHD, and otherwise healthy preterm infants, respectively. Attributable RSV admission frequencies were estimated to be 13.6%, 16.5%, and 4.1%, respectively.

Conclusions

Mexican preterm infants, particularly those with BPD, have high rates of ARI‐ and RSVassociated hospitalizations. Specific interventions to reduce the incidence of severe infections in this highrisk group are required.

The burden of respiratory syncytial virus (RSV) associated acute lower respiratory infections in children with Down syndrome: A systematic review and meta-analysis

Background

Acute lower respiratory tract infections (ALRIs) caused by respiratory syncytial virus (RSV) are a leading cause of hospitalization in infants. Numerous risk factors have been identified in the aetiology of severe RSV–associated ALRI necessitating hospitalisation, including prematurity and congenital heart disease. Down syndrome (DS), a common genetic disorder associated with congenital and dysmorphic features, has recently been identified as an independent risk factor for RSV–associated ALRI requiring hospitalisation; however, the disease burden of RSV–associated ALRI in this population has not yet been established. Similarly, the impact of DS as an independent risk factor has not yet been quantified. We aimed therefore to estimate the incidence of admissions in children with DS, and by comparing this with unaffected children, to quantify the risk of DS independent of other risk factors.

Methods

A systematic review of the existing literature published between 1995 and March 1, 2017 was performed to quantify the incidence of hospitalisation due to RSV–associated ALRI in children with DS. Meta–analyses were performed on extracted data using STATA statistical software, and hospitalisation rates for children with and without DS under the age of 2 were calculated.

Findings

5 articles were ultimately deemed eligible for analyses. Analyses were limited to children under the age of 2 years. We calculated the hospitalisation rate for children with DS in this age group to be 117.6 per 1000 child–years (95% CI 67.4–205.2), vs a rate of 15.2 per 1000 child–years (95% CI 8.3–27.6) in unaffected children. This indicates DS contributes to a 6.8 (95% CI 5.5–8.4) fold increase in the relative risk of hospitalisation for RSV–associated ALRI.

Interpretation

Though limited by a small number of articles, this review found sufficient evidence to conclude DS was a significant independent risk factor for the development of severe RSV–associated ALRI requiring hospitalisation. Further studies are needed to define the impact of DS in conjunction with other comorbidities on the risk of severe RSV infection. Determining benefits of immunoprophylaxis or future vaccines against RSV in this at–risk population is warranted.

Burden of severe RSV disease among immunocompromised children and adults: a 10 year retrospective study

Background

Respiratory syncytial virus (RSV) is associated with significant mortality rates amongst hematopoietic stem cell transplant (HSCT) recipients, with less known about other immunocompromised patients.

Methods

Ten-year retrospective cohort study of immunocompromised patients presenting with RSV disease documented at University Hospitals of Lausanne and Geneva. Severe RSV-related outcomes referred to RSV documented respiratory conditions requiring hospital admission, presenting as lower respiratory tract infection (LRTI) or pneumonia. We used multivariable logistic regression to assess clinical and laboratory correlates of severe RSV disease.

Results

From 239 RSV-positive immunocompromised in and out-patients 175 were adults and 64 children of whom 111 (47.8%) presented with LRTI, which resulted in a 38% (89/239) admission rate to hospital. While immunocompromised children were more likely to be admitted to hospital compared to adults (75% vs 62.9%, p = 0.090), inpatients admitted to the intensive care unit (17/19) or those who died (11/11) were mainly adults. From multivariable analyses, adults with solid tumors (OR 5.2; 95% CI: 1.4–20.9 P = 0.015) or those requiring chronic immunosuppressive treatments mainly for rheumatologic conditions (OR 4.1; 95% CI: 1.1–16.0; P = 0.034) were significantly more likely to be admitted to hospital compared to hematopoietic stem cell (HSCT) recipients. Bacterial co-infection was significantly and consistently associated with viral LRTI and pneumonia.

Conclusions

From our findings, RSV-related disease results in a significant burden among adults requiring chronic immunosuppressive treatments for rheumatological conditions and those with solid tumors. As such, systematic screening for respiratory viruses, should be extended to other immunocompromised populations than HSCT recipients.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3002-3) contains supplementary material, which is available to authorized users.

Defining the Risk and Associated Morbidity and Mortality of Severe Respiratory Syncytial Virus Infection Among Infants with Congenital Heart Disease

Introduction

The REGAL (RSV Evidence—a Geographical Archive of the Literature) series provide a comprehensive review of the published evidence in the field of respiratory syncytial virus (RSV) in Western countries over the last 20 years. This fourth publication covers the risk and burden of RSV infection in infants with congenital heart disease (CHD).

Methods

A systematic review was undertaken for articles published between January 1, 1995 and December 31, 2015 across PubMed, Embase, The Cochrane Library, and Clinicaltrials.gov. Studies reporting data for hospital visits/admissions for RSV infection among children with CHD as well as studies reporting RSV-associated morbidity, mortality, and healthcare costs were included. The focus was on children not receiving RSV prophylaxis. Study quality and strength of evidence (SOE) were graded using recognized criteria.

Results

A total of 1325 studies were identified of which 38 were included. CHD, in particular hemodynamically significant CHD, is an independent predictor for RSV hospitalization (RSVH) (high SOE). RSVH rates were generally high in young children (<4 years) with CHD (various classifications), varying between 14 and 357/1000 (high SOE). Children (<6 years) with RSV infection spent 4.4–14 days in hospital, with up to 53% requiring intensive care (high SOE). Infants (<2 years) with CHD had a more severe course of RSVH than those without CHD (high SOE). Case fatality rates of up to 3% were associated with RSV infection in children with CHD (high SOE). RSV infection in the perioperative period of corrective surgery and nosocomial RSV infection in intensive care units also represent important causes of morbidity (moderate SOE).

Conclusion

CHD poses a significant risk for RSVH and subsequent morbidity and mortality. RSV infection often complicates corrective heart surgery. To reduce the burden and improve outcomes, further research and specific studies are needed to determine the longer-term effects of severe RSV infection in young children with CHD.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-016-0142-x) contains supplementary material, which is available to authorized users.

Respiratory syncytial virus-associated hospitalizations over three consecutive seasons in children with congenital heart disease

The purpose of this investigation was to analyze the burden of respiratory syncytial virus (RSV)-related hospitalizations in infants and children with congenital heart disease (CHD) over three consecutive RSV seasons. Retrospectively, all children with hemodynamically significant (HS-CHD) and not significant (HNS-CHD) CHD born between 2004 and 2008 at a tertiary care university hospital and identified by ICD-10 diagnoses were included. Data on RSV-related hospitalizations over the first three years of life covering at least three RSV seasons (November-April) were analyzed. The overall incidence of RSV-related hospitalization was 9.6 % (58/602), without a statistically significant difference between HS-CHD and HNS-CHD (7.3 % vs. 10.4 %; p = 0.258). Recommendation of palivizumab prophylaxis did not influence the RSV hospitalization rates between groups. Patients with HS-CHD and early surgery were significantly less often hospitalized due to RSV compared to those with delayed surgery (1.3 % vs. 14.3 %; p = 0.003). The median duration of hospitalization was 8.5 days (HS-CHD: 14 vs.

HNS-CHD

7 days; p = 0.003). Thirteen patients (22.4 %) were admitted to the intensive care unit (ICU), for a median of 10 days. The median age at admission was 2 months, with a significant difference between HS-CHD and HNS-CHD (6 vs. 2 months; p = 0.001). The majority (97 %) of RSV-related hospitalizations occurred before 12 months of age. Patients with HS-CHD had a significantly more severe course of RSV disease and were older at the time of hospitalization. Early surgery seemed to significantly reduce the risk of RSV hospitalization during the first RSV season.

Risk of Respiratory Syncytial Virus Infection in Cyanotic Congenital Heart Disease in a Subtropical Area

OBJECTIVE

To compare the risk of respiratory syncytial virus (RSV)-associated hospitalization and analyze the epidemiology of RSV infection in patients with cyanotic and acyanotic congenital heart disease (CHD), we analyzed the nationwide health insurance database from 2005-2010.

STUDY DESIGN

This study included 1050 patients with cyanotic CHD and 7077 patients with acyanotic CHD. Patients with acyanotic CHD were further classified into hemodynamically significant (hs)-acyanotic and non-hs-acyanotic groups according to whether they underwent surgery or took at least 2 anticongestive medications.

RESULTS

RSV-associated hospitalization was higher in the cyanotic group than in hs-acyanotic and non-hs-acyanotic groups both before 1 year of age (4.8% vs 2.1% vs 1.5%, P < .001) and between 1 and 2 years of age (0.9% vs 0.56% vs 0.14%, P = .003). The hospitalization duration, intensive care, ventilator support prevalence, hospitalization cost, and mortality rate were significantly higher in the cyanotic group than in the other 2 groups. Logistic regression revealed that cyanotic CHD was the most significant risk factor for the ventilator support and RSV-associated mortality. In both patients with cyanotic and acyanotic CHD, RSV-associated hospitalization rate was higher in patients aged younger than 1 year and in spring and autumn in Taiwan, a subtropical country.

CONCLUSIONS

The results show that patients with cyanotic CHD have a higher risk of severe RSV infection than do those with acyanotic CHD. RSV prophylaxis is more important and may reduce costs more for patients with cyanotic CHD.

Preventing hospitalizations for respiratory syncytial virus infection

Respiratory syncytial virus infection is the leading cause of lower respiratory tract infections in young children. Palivizumab has minimal impact on RSV hospitilization rates as it is only practical to offer it to the highest risk groups. The present statement reviews the published literature and provides updated recommendations regarding palivizumab use in children in Canada.

Clinical practice guideline: the diagnosis, management, and prevention of bronchiolitis

This guideline is a revision of the clinical practice guideline, "Diagnosis and Management of Bronchiolitis," published by the American Academy of Pediatrics in 2006. The guideline applies to children from 1 through 23 months of age. Other exclusions are noted. Each key action statement indicates level of evidence, benefit-harm relationship, and level of recommendation. Key action statements are as follows:

Updated guidance for palivizumab prophylaxis among infants and young children at increased risk of hospitalization for respiratory syncytial virus infection

Guidance from the American Academy of Pediatrics (AAP) for the use of palivizumab prophylaxis against respiratory syncytial virus (RSV) was first published in a policy statement in 1998. Guidance initially was based on the result from a single randomized, placebo-controlled clinical trial conducted in 1996-1997 describing an overall reduction in RSV hospitalization rate from 10.6% among placebo recipients to 4.8% among children who received prophylaxis. The results of a second randomized, placebo-controlled trial of children with hemodynamically significant heart disease were published in 2003 and revealed a reduction in RSV hospitalization rate from 9.7% in control subjects to 5.3% among prophylaxis recipients. Because no additional controlled trials regarding efficacy were published, AAP guidance has been updated periodically to reflect the most recent literature regarding children at greatest risk of severe disease. Since the last update in 2012, new data have become available regarding the seasonality of RSV circulation, palivizumab pharmacokinetics, the changing incidence of bronchiolitis hospitalizations, the effects of gestational age and other risk factors on RSV hospitalization rates, the mortality of children hospitalized with RSV infection, and the effect of prophylaxis on wheezing and palivizumab-resistant RSV isolates. These data enable further refinement of AAP guidance to most clearly focus on those children at greatest risk.

Respiratory syncytial virus bronchiolitis in children

Respiratory syncytial virus is a highly infectious virus that commonly causes bronchiolitis and leads to high morbidity and a low, but important, incidence of mortality. Supportive therapy is the foundation of management. Hydration/nutrition and respiratory support are important evidence-based interventions. For children with severe disease, continuous positive airway pressure or mechanical ventilation may be necessary. Ribavirin may be used for treatment of patients with severe disease. Palivizumab provides important ongoing immunoprophylaxis during epidemic months for high-risk infants. Caregiver education and incorporating an explanation of all therapies and anticipatory guidance, including strategies for reducing the risk of infection, are vital.

Palivizumab prophylaxis during nosocomial outbreaks of respiratory syncytial virus in a neonatal intensive care unit: predicting effectiveness with an artificial neural network model

STUDY OBJECTIVE

To identify subgroups of premature infants who may benefit from palivizumab prophylaxis during nosocomial outbreaks of respiratory syncytial virus (RSV) infection.

DESIGN

Retrospective analysis using an artificial intelligence model.

SETTING

Level IIIB, 35-bed, neonatal intensive care unit (NICU) at a tertiary care hospital in the United Arab Emirates.

PATIENTS

One hundred seventy six premature infants, born at a gestational age of 22-34 weeks, and hospitalized during four RSV outbreaks that occurred between April 2005 and July 2007.

MEASUREMENTS AND MAIN RESULTS

We collected demographic and clinical data for each patient by using a standardized form. Input data consisted of seven categoric and continuous variables each. We trained, tested, and validated artificial neural networks for three outcomes of interest: mortality, days of supplemental oxygen, and length of NICU stay after the index case was identified. We compared variable impacts and performed reassignments with live predictions to evaluate the effect of palivizumab. Of the 176 infants, 31 (17.6%) received palivizumab during the outbreaks. All neural network configurations converged within 4 seconds in less than 400 training cycles. Infants who received palivizumab required supplemental oxygen for a shorter duration compared with controls (105.2 ± 7.2 days vs 113.2 ± 10.4 days, p=0.003). This benefit was statistically significant in male infants whose birth weight was less than 0.7 kg and who had hemodynamically significant congenital heart disease. Length of NICU stay after identification of the index case and mortality were independent of palivizumab use.

CONCLUSION

Palivizumab may be an effective intervention during nosocomial outbreaks of RSV in a subgroup of extremely low-birth-weight male infants with hemodynamically significant congenital heart disease.

Respiratory syncytial virus infections in infants and children with congenital heart disease: update on the evidence of prevention with palivizumab

PURPOSE OF REVIEW

Lower respiratory tract infections multiply morbidity and mortality within patients with significant congenital heart disease (CHD). For respiratory syncytial virus (RSV), one of the most important pathogens, immunoprophylaxis with palivizumab has successfully been introduced. The question is which patients will benefit most from this costly preventive treatment.

RECENT FINDINGS

The era after the introduction of palivizumab has revealed a steep decrease in mortality. The markers of success - hospital stays, admission to the intensive care unit, days on mechanical ventilation, and death - consistently favor immunoprophylaxis. The key point of treatment success remains in all cases a careful patient selection, adherence to a time limit of 30 days between the injections and early use after cardiac surgery with cardiopulmonary bypass, as well as avoidance of nosocomial-acquired infections. Preventive therapy with palivizumab in patients with CHD has been investigated in terms of operating efficiency - with the lowest costs per quality-adjusted life years compared with preterm infants with or without bronchopulmonary dysplasia.

SUMMARY

The burden of RSV disease will decline, once a vaccine is available. Meanwhile, immunoprophylaxis with palivizumab is a useful tool for high-risk patients to reduce comorbidity and fatal outcome. Pharmacoeconomic considerations measuring quality-adjusted life years indicate important information about cost-effectiveness.

The cost effectiveness of palivizumab in congenital heart disease: a review of the current evidence

OBJECTIVE

To review and summarize the literature concerning the cost-effectiveness of palivizumab compared to no prophylaxis in infants and young children with congenital heart disease (CHD).

METHODS

A systematic literature search (MEDLINE to March 2012, limited to English language) identified studies that examined the cost-effectiveness of palivizumab in CHD populations. The quality of each study was assigned a quality score of 1-100 based on the Quality of Health Economic Studies (QHES) instrument.

RESULTS

Ten studies were identified through the search strategy, of which four principally addressed the research question and six additional articles examined CHD in conjunction with other high-risk indications for palivizumab in their economic analyses. QHES for the studies ranged from 58-100, with a median score of 93 (76 for principal articles, 94 for secondary analyses). Cost-utility analyses, which evaluated costs per quality-adjusted life year (QALY), showed favorable results in five analyses (range $10,329-$16,648 per QALY), while the other two suggested no cost-effectiveness ($146,061 and $169,971 per QALY). Of three cost-effectiveness analyses, which assessed costs per hospital admission prevented (HAP), two concluded that the drug was not cost-effective ($16,216/day of hospitalization prevented and $868,296/HAP), while one did not interpret the final result ($43,561/HAP).

LIMITATIONS

Significant variance exists across study characteristics, analytic models utilized, duration of RSV seasons assessed, primary outcome measures evaluated, sensitivity analyses conducted, and other model assumptions. Further, it was difficult to obtain true CHD-based quality scores for the studies that analyzed more than one indication.

CONCLUSIONS

The findings of this review currently remain inconclusive. Although a favorable trend was identified in the cost-utility analyses, additional rigorously conducted studies are necessary to better estimate the cost-effectiveness of palivizumab for CHD infants in clinical practice.

Managing the morbidity associated with respiratory viral infections in children with congenital heart disease

Children with congenital heart disease (CHD) are at risk for increased morbidity from viral lower respiratory tract infections because of anatomical cardiac lesions than can worsen an already compromised respiratory status. Respiratory syncytial virus (RSV) remains an important pathogen in contributing toward the morbidity in this population. Although the acute treatment of RSV largely remains supportive, the development of monoclonal antibodies, such as palivuzumab, has reduced the RSV-related hospitalization rate in children with CHD. This review highlights the specific cardiac complications of RSV infection, the acute treatment of bronchiolitis in patients with CHD, and the search for new therapies against RSV, including an effective vaccine, because of the high cost associated with immunoprophylaxis and its lack of reducing RSV-related mortality.

Respiratory syncytial virus- and influenza virus-associated hospitalizations in infants less than 12 months of age

Infants hospitalized because of respiratory syncytial virus (RSV) infection (n = 388) were significantly younger, had longer hospital stays, had a more severe course of disease, and required supplemental oxygen more often with longer duration of treatment as compared with those with influenza virus (n = 37) infection. Seasonal distribution varied, with RSV-associated hospitalizations peaking in January and influenza virus-associated hospitalizations in February. Congenital heart disease was more commonly a risk factor in infants with RSV infection.

Epidemiology and prevention of respiratory syncytial virus infections among infants and young children

Since its discovery in 1956, respiratory syncytial virus (RSV) has been recognized as one of the most common causes of serious lower respiratory tract infections in young children worldwide. While considered a high priority, development of a safe and effective vaccine has remained elusive. Prevention of RSV disease relies on infection control and hygiene measures, as well as providing immunoprophylaxis in select infants. The prophylaxis, however, is costly, and so targeting the recipient population and timing of administration is important for optimal effectiveness and judicious use of limited health care resources. This article reviews the epidemiology of RSV infections in infants and young children, including risk factors for severe disease, so as to inform decisions about prevention efforts.

Respiratory syncytial virus infection in children with congenital heart disease: global data and interim results of Korean RSV-CHD survey

Respiratory syncytial virus (RSV) is a main cause of hospitalization for bronchiolitis and pneumonia in infants worldwide. Children with hemodynamically significant congenital heart disease (HS-CHD), as well as premature infants are at high risk for severe RSV diseases. Mortality rates for CHD patients hospitalized with RSV have been reported as about 24 times higher compared with those without RSV infection. Recently with advances in intensive care, mortality rates in CHD patients combined with RSV have decreased below 2%. The requirements of intensive care and mechanical ventilation for CHD patients with RSV infection were still higher than those without RSV infection or with non-CHD children. RSV infection has frequently threatened CHD infants with congestive heart failure, cyanosis, or with pulmonary hypertension. As a progressive RSV pneumonitis in those infants develops, the impairment of oxygen uptake, the breathing workload gradually increases and eventually causes to significant pulmonary hypertension, even after the operation. Preventing RSV infection as much as possible is very important, especially in infants with HS-CHD. A humanized monoclonal antibody, palivizumab, has effective in preventing severe RSV disease in high-risk infants, and progressive advances in supportive care including pulmonary vasodilator have dramatically decreased the mortality (<1%). Depending on the global trend, Korean Health Insurance guidelines have approved the use of palivizumab in children <1 year of age with HS-CHD since 2009. Korean data are collected for RSV prophylaxis in infants with CHD.

[Clinical consensus on respiratory syncytial virus (RSV) infection prophylaxis and the use of palivizumab in paediatric cardiology.]

BACKGROUND

Following the results of the CIVIC study, the SECPCC proposes to revise its recommendations for the prevention of RSV, taking into account the new evidence, as well as the preventive experience of paediatric cardiologists. For this purpose a structured method of professional consensus has been chosen.

OBJECTIVES

To develop a Spanish clinical consensus on preventing infection by RSV under the auspices of the Sociedad Española de Cardiología Pediátrica y Cardiopatías Congénitas.

METHODS

Delphi Consensus modified in two rounds. The study was conducted in four phases: 1) constitution of a Scientific Committee for bibliographic review and submission of the recommendations for discussion, 2) constitution of an Expert Panel with 75 representatives in the speciality, 3) postal survey organised in two rounds and intermediate processing of opinions, and issuing of a report to the panellists, and 4) discussion of the results in a face-to-face meeting of the Scientific Committee.

RESULTS

Consensus was reached on 54 of the 70 preventive recommendations analysed. With respect to the 16 remaining issues, no consensus was reached, due to differences in professional opinion and the absence of established criteria among the majority of the experts.

CONCLUSIONS

A set of recommendations for RSV prophylaxis in cardiology was developed and updated, rated in accordance with the degree of professional consensus on which they were based. These can be considered valid until such time as new scientific information emerges that warrants a further review.

[Consensus conference on acute bronchiolitis (VI): prognosis of acute bronchiolitis. Review of scientific evidence]

We present a review of the evidence on prognosis of acute bronchiolitis, risk factors for severe forms, symptom or severity scores and risk of post-bronchiolitis asthma. Documented risk factors of long stay or PICU admission in hospitalized patients are: bronchopulmonary dysplasia and/or chronic lung disease, prematurity, congenital heart disease and age less than 3 months. Other less well documented risk factors are: tobacco exposure, history of neonatal mechanical ventilation, breastfeeding for less than 4 months, viral co-infection and other chronic diseases. There are several markers of severity: toxic appearance, tachypnea, hypoxia, atelectasis or infiltrate on chest radiograph, increased breathing effort, signs of dehydration, tachycardia and fever. Although we have some predictive models of severity, none has shown sufficient predictive validity to recommend its use in clinical practice. While there are different symptom or severity scores, none has proven to be valid or accurate enough to recommend their preferable application in clinical practice. There seems to be a consistent and strong association between admission due to bronchiolitis and recurrent episodes of wheezing in the first five years of life. However it is unclear whether this association continues in subsequent years, as there are discordant data on the association between bronchiolitis and asthma.

[Consensus conference on acute bronchiolitis (II): epidemiology of acute bronchiolitis. Review of the scientific evidence]

A review of the evidence on epidemiology, risk factors, etiology and clinical-etiological profile of acute bronchiolitis is presented. The frequency estimates are very heterogeneous; in the population under two years the frequency of admission for bronchiolitis is between 1 and 3.5%, primary care consultations between 4 and 20% and emergency visits between 1 and 2%. The frequency of admissions for respiratory infection by respiratory syncytial virus in the risk population is: in premature infants < or =32 weeks of gestation between 4.4 and 18%, in patients with bronchopulmonary dysplasia between 7.3 and 42%, and in infants with congenital heart disease between 1.6 and 9.8%. The main risk factors are: prematurity, chronic lung disease or bronchopulmonary dysplasia, congenital heart disease and age less than 3-6 months at onset of the epidemic. Other factors are: older siblings or day care attendance, male gender, exposure to smoking, breastfeeding for less than 1-2 months and variables associated with lower socioeconomic status. Respiratory syncytial virus is the dominant etiological agent, constituting just over half the cases (median 56%; interval 27% to 73%). Other viruses implicated, in descending order of frequency, are rhinovirus, adenovirus, metapneumovirus, influenza viruses, parainfluenza, enterovirus and bocavirus. In studies with genomic detection techniques, between 20 and 25% of cases the virus involved is not identified and between 9% and 27% of cases have viral co-infection. Although respiratory syncytial virus bronchiolitis shows more wheezing and retractions, longer duration of respiratory symptoms and oxygen therapy and are associated with lower use of antibiotics. This pattern is associated with the younger age of the patients and does not help us to predict the etiology. In general, the etiological identification is not useful for the management of patients. However, in young infants (<3 months) with febrile bronchiolitis in the hospital environment, conservative management may help these patients and avoid diagnostic and therapeutic procedures.

Prospective population-based study of RSV-related intermediate care and intensive care unit admissions in Switzerland over a 4-year period (2001-2005)

OBJECTIVES

Respiratory syncytial virus (RSV) infections are a leading cause of hospital admissions in small children. A substantial proportion of these patients require medical and nursing care, which can only be provided in intermediate (IMC) or intensive care units (ICU). This article reports on all children aged < 3 years who required admission to IMC and/or ICU between October 1, 2001 and September 30, 2005 in Switzerland.

PATIENTS AND METHODS

We prospectively collected data on all children aged < 3 years who were admitted to an IMC or ICU for an RSV-related illness. Using a detailed questionnaire, we collected information on risk factors, therapy requirements, length of stay in the IMC/ICU and hospital, and outcome.

RESULTS

Of the 577 cases reported during the study period, 90 were excluded because the patients did not fulfill the inclusion criteria; data were incomplete in another 25 cases (5%). Therefore, a total of 462 verified cases were eligible for analysis. At the time of hospital admission, only 31 patients (11%) were older than 12 months. Since RSV infection was not the main reason for IMC/ICU admission in 52% of these patients, we chose to exclude this subgroup from further analyses. Among the 431 infants aged < 12 months, the majority (77%) were former near term or full term (NT/FT) infants with a gestational age > or = 35 weeks without additional risk factors who were hospitalized at a median age of 1.5 months. Gestational age (GA) < 32 weeks, moderate to severe bronchopulmonary dysplasia (BPD), and congenital heart disease (CHD) were all associated with a significant risk increase for IMC/ICU admission (relative risk 14, 56, and 10, for GA < or = 32 weeks, BPD, and CHD, respectively). Compared with NT/FT infants, high-risk infants were hospitalized at an older age (except for infants with CHD), required more invasive and longer respiratory support, and had longer stays in the IMC/ICU and hospital.

CONCLUSIONS

In Switzerland, RSV infections lead to the IMC/ICU admission of approximately 1%-2% of each annual birth cohort. Although prematurity, BPD, and CHD are significant risk factors, non-pharmacological preventive strategies should not be restricted to these high-risk patients but also target young NT/FT infants since they constitute 77% of infants requiring IMC/ICU admission.

Respiratory syncytial virus infection in 406 hospitalized premature infants: results from a prospective German multicentre database

Premature birth, chronic lung disease of prematurity (CLD), congenital heart disease and immunodeficiency predispose to a higher morbidity and mortality in respiratory syncytial virus (RSV) infection. This study describes the preterms hospitalised with RSV infection from the prospective German DSM RSV Paed database. The DMS RSV Paed database was designed for the prospective multicentre documentation and analysis of clinically relevant aspects of the management of inpatients with RSV infection. This study covers six consecutive RSV seasons (1999-2005); the surveillance took place in 14 paediatric hospitals in Germany. Of the 1,568 prospectively documented RSV infections, 26% (n=406) were observed in preterms [vs. 1,162 children born at term (74%)] and 3% (n=50) had CLD, of which 49 had received treatment in the last 6 months ('CLDplus'). A significantly higher proportion in the preterm group had congenital heart disease, nosocomial infection, and neuromuscular impairment. There were significantly more children older than 24 months in the preterm group. The attributable mortality was 0.2% (n=2) in children born at term vs. 1.2% (n=5) in the preterm group (p=0.015) [preterm plus CLD 8.0% (n=4 of 50); McIntosh grade 1, 8.6% (n=3 of 35) and McIntosh Grade 4, 15% (n=3 of 20)]. Eight patients were categorized as 'palivizumab failures'. In the multivariate analysis, premature birth, CLD(plus), and nosocomial infection were significantly and independently associated with the combined outcome 'complicated course of disease'. In conclusion, this is the first prospective multicentre study from Germany that confirms the increased risk for severe RSV disease in preterms, in particular in those with CLD treated in the last 6 months before the onset of the infection. From the perspective of our results, the statements of the German Society of Paediatric Infectious Diseases considering the use of passive immunisation (2003) seem reasonable.

Palivizumab in congenital heart disease: should international guidelines be revised?

Palivizumab has reduced the incidence of respiratory syncytial virus hospitalization in infants and children with congenital heart disease by 45%. Although the mortality rate of children with congenital heart disease hospitalized with respiratory syncytial virus infection has declined from 37% to approximately 3% over the past 3 decades, palivizumab has not been shown to improve mortality. There has been considerable controversy over the cost-effectiveness of administering palivizumab according to international guidelines, including children with congenital heart disease. In particular, the number of children that need to be treated with palivizumab to prevent one respiratory syncytial virus hospitalization increases dramatically in children > 12 months of age. As a result, the authors recommend that countries re-examine their recommendations for providing palivizumab up to age 24 months in children with congenital heart disease.

Palivizumab and the prevention of respiratory syncytial virus illness in pediatric patients with congenital heart disease

Respiratory syncytial virus (RSV) is a significant pathogen for infants and children with congenital heart disease. Non-sustained immunity and failure to develop an effective vaccine has steered RSV management toward a passive immunotherapy strategy in at-risk children. Palivizumab is a humanized murine monoclonal antibody targeting the RSV envelope F glycoprotein. In a Phase III clinical trial palivizumab significantly reduced RSV hospitalization in children with significant congenital heart disease and was proven to be safe. Palivizumab is one of the first monoclonal antibodies to significantly impact a pediatric disease.

Respiratory infection in congenital cardiac disease. Hospitalizations in young children in Spain during 2004 and 2005: the CIVIC Epidemiologic Study

OBJECTIVES

To evaluate the rate of hospitalization for acute respiratory tract infection in children less than 24 months with haemodynamically significant congenital cardiac disease, and to describe associated risk factors, preventive measures, aetiology, and clinical course.

MATERIALS AND METHODS

We followed 760 subjects from October 2004 through April 2005 in an epidemiological, multicentric, observational, follow-up, prospective study involving 53 Spanish hospitals.

RESULTS

Of our cohort, 79 patients (10.4%, 95% CI: 8.2%-12.6%) required a total of 105 admissions to hospital related to respiratory infections. The incidence rate was 21.4 new admissions per 1000 patients-months. Significant associated risk factors for hospitalization included, with odds ratios and 95% confidence intervals shown in parentheses: 22q11 deletion (8.2, 2.5-26.3), weight below the 10th centile (5.2, 1.6-17.4), previous respiratory disease (4.5, 2.3-8.6), incomplete immunoprophylaxis against respiratory syncytial virus (2.2, 1.2-3.9), trisomy 21 (2.1, 1.1-4.2), cardiopulmonary bypass (2.0, 1.1-3.4), and siblings aged less than 11 years old (1.7, 1.1-2.9). Bronchiolitis (51.4%), upper respiratory tract infections (25.7%), and pneumonia (20%) were the main diagnoses. An infectious agent was found in 37 cases (35.2%): respiratory syncytial virus in 25, Streptococcus pneumoniae in 5, and Haemophilus influenzae in 4. The odds ratio for hospitalization due to infection by the respiratory syncytial virus increases by 3.05 (95% CI: 2.14 to 4.35) in patients with incomplete prophylaxis. The median length of hospitalization was 7 days. In 18 patients (17.1%), the clinical course of respiratory infection was complicated and 2 died.

CONCLUSIONS

Hospital admissions for respiratory infection in young children with haemodynamically significant congenital cardiac disease are mainly associated with non-cardiac conditions, which may be genetic, malnutrition, or respiratory, and to cardiopulmonary bypass. Respiratory syncytial virus was the most commonly identified infectious agent. Incomplete immunoprophylaxis against the virus increased the risk of hospitalization.

Hospitalized children with respiratory syncytial virus infection and neuromuscular impairment face an increased risk of a complicated course

BACKGROUND

Respiratory syncytial virus (RSV) infection is an important cause of viral respiratory tract infection in children. In contrast to other confirmed risk factors that predispose to a higher morbidity and mortality, the particular risk of a preexisting neuromuscular impairment (NMI) in hospitalized children with RSV infection has not been prospectively studied in a multicenter trial.

METHODS

The DMS RSV Paed database was designed for the prospective multicenter documentation and analysis of all clinically relevant aspects of the management of inpatients with RSV infection. Patients with clinically relevant NMI were identified according to the specific comments of the attending physicians and compared with those without NMI.

RESULTS

This study covers 6 consecutive seasons; the surveillance took place in 14 pediatric hospitals in Germany from 1999 to 2005. In total, 1568 RSV infections were prospectively documented in 1541 pediatric patients. Of these, 73 (4.7%) patients displayed a clinically relevant NMI; 41 (56%) NMI patients had at least 1 additional risk factor for a severe course of the infection (multiple risk factors in some patients; prematurity in 30, congenital heart disease in 19, chronic lung disease 6 and immunodeficiency in 8). Median age at diagnosis was higher in NMI patients (14 vs. 5 months); NMI patients had a greater risk of seizures (15.1% vs. 1.6%), and a higher proportion in the NMI group had to be mechanically ventilated (9.6% vs. 1.9%). Eventually, the attributable mortality was significantly higher in the NMI group (5.5% vs. 0.2%; P < 0.001 for all). Multivariate logistic regression confirmed that NMI was independently associated with pediatric intensive care unit (PICU) admission (OR, 4.94; 95% CI, 2.69-8.94; P < 0.001] and mechanical ventilation (OR, 3.85; 95% CI, 1.28-10.22; P = 0.017).

CONCLUSION

This is the first prospective multicenter study confirming the hypothesis that children with clinically relevant NMI face an increased risk for severe RSV-disease. It seems reasonable to include NMI as a cofactor into the decision algorithm of passive immunization.

Palivizumab: a review of its use in the protection of high risk infants against respiratory syncytial virus (RSV)

Respiratory syncytial virus (RSV) is a leading cause of hospitalization in children less than 1 year of age and causes substantial morbidity. Although there is not currently a vaccine available to prevent RSV infection, prophylaxis with the humanized monoclonal antibody palivizumab has been shown to reduce the rate of RSV hospitalization in premature infants and those infants with chronic lung disease or congenital heart disease. Because palivizumab has not been shown to have a beneficial clinical effect on established RSV disease such as reducing the rate of mechanical ventilation and mortality in children afflicted with RSV, there has been considerable debate as to the cost-benefit ratio of administering palivizumab according to international guidelines. Palivizumab has demonstrated a favorable side-effect profile in clinical trials without the development of anti-palivizumab antibodies. Future studies are needed to determine whether palivizumab, or other more potent monoclonal antibodies which are currently undergoing clinical trials, will reduce the long-term sequelae of RSV infection such as the development of wheezing and asthma.

Respiratory syncytial virus infections in congenital heart defects--hospitalizations and costs

AIMS

To register hospitalizations for respiratory syncytial virus (RSV) infections and estimate costs of prophylaxis with humanized monoclonal antibodies (palivizumab) against RSV, compared to hospital care, in cases with congenital heart defects (CHDs).

METHODS

Population based study with prospective registration of CHDs. Costs for hospital treatment of RSV-infections in CHD-patients calculated by means of the Norwegian Diagnosis Related Groups system.

RESULTS

In 43 470 infants live born in the population through the 18-year period 1987-2004 a structural CHD was diagnosed in 527 (1.2%). A total of 898 (2.1%) hospitalizations for RSV-infections occurred in the study population 1987-2005. The hospital admittance rate was significantly higher for CHD-cases (4.8%) than for children without CHD (2%) (P = 0.002). Severe CHDs (need for surgery or catheter intervention) had a higher admittance rate (9.2%) compared to the group of remaining CHDs (3.3%) (P = 0.01). Number needed to treat with palivizumab to avoid one hospitalization for RSV-infection in cases of severe CHDs was calculated to 24, at costs of US dollar 195,000. The expenses for palivizuamab prophylaxis in severe CHDs were 31 times that of hospital treatment.

CONCLUSION

Prophylaxis with palivizumab in severe CHDs is not cost-effective.

Palivizumab use among children with congenital heart disease in Quebec: Impact of Canadian guidelines on clinical practice

BACKGROUND

Palivizumab has been shown to reduce the risk of hospitalization caused by respiratory syncytial virus in children with congenital heart disease (CHD). Guidelines published in 2003 by the Canadian Paediatric Society (CPS) stated that children younger than 24 months with hemodynamically significant CHD should be considered for up to five monthly doses of palivizumab during the winter season.

OBJECTIVE

To assess the impact of CPS guidelines on the use of palivizumab in children with CHD.

METHODS

Clinical information was reviewed on all patients with CHD who were prescribed palivizumab in 2002-2003 and 2003-2004 and who were followed by one of four paediatric cardiovascular programs in the province of Quebec.

RESULTS

Palivizumab was prescribed to 45 children in 2002-2003 and to 146 children in 2003-2004. The number of children receiving more than five doses increased from 10 of 45 (22%) in 2002-2003 to 57 of 128 (45%) in 2003-2004 (P=0.008). One hundred seventeen of 146 children (80%) receiving palivizumab in 2003-2004 met the CPS guidelines versus 38 of 45 children (84%) in 2002-2003 (ie, before the guidelines were published) (P=0.66). Patients not meeting CPS criteria were older than 24 months at the time of the first dose, had hemodynamically insignificant CHD or had lesions adequately corrected by surgery.

CONCLUSIONS

The number of children with CHD receiving palivizumab prophylaxis increased significantly following the publication of CPS guidelines. The majority of children were eligible for palivizumab according to the current CPS criteria. More patients received more than five doses in 2003-2004 than in 2002-2003.

The potential impact of prophylaxis against bronchiolitis due to the respiratory syncytial virus in children with congenital cardiac malformations

AIMS

To determine the number of infants in the Mersey and North West regions with congenital cardiac disease for whom palivizumab may be appropriate, and to examine the potential impact of introducing prophylaxis with palivizumab on these patients and their economic management.

METHODS

We identified those infants deemed to be at high risk, matching the population recently studied by the Cardiac Synagis Group, from the database of the cardiology department of the hospital. The number of patients under the care of the paediatric cardiologists admitted to Alder Hey Hospital with respiratory syncytial viral bronchiolitis over the last three seasons was identified from hospital coding records, and the database of the cardiology department.

RESULTS

There are 131 patients at high risk each year. Of these, over the last three "bronchiolitis seasons", 39 infants have been admitted to the hospital with bronchiolitis due to the respiratory syncytial virus. This represents a hospitalisation rate of 10 per cent, as was seen in the study of the Cardiac Synagis Group. Using a monthly dose of 15 milligrams per kilogram for five doses, the cost per patient is 2,650 pounds sterling for the season. To treat the 131 patients seen at Alder Hey, therefore, would cost 346,800 pounds each year. Applying the reductions in hospitalisation identified in the study by the Cardiac Synagis Group to our population would produce an expected reduction in patients hospitalised from 13 to 7 per year, reducing the total length of stay in our hospital wards from 169 to 76 days, and in the paediatric intensive care unit from 93 to 21 days. This amounts to a potential saving of 190,800 pounds per year. Reducing transfers to more distant paediatric intensive care units for referrals refused because of lack of beds could save an additional 50,000 pounds.

DISCUSSION

We estimate the net cost of introducing palivizumab for this population to be 106,000 pounds per year. There would, of course, be additional costs involved in setting up this service, as well as additional savings and benefits. This cost is comparable with other new biologic therapies now routinely used in the United Kingdom, such as etanercept for juvenile arthritis. There are, currently, no other obvious therapies that have the potential to reduce admissions to hospital and intensive care during the winter months, when beds are at their most scarce.

The European Forum for Clinical Management: prophylaxis against the respiratory syncytial virus in infants and young children with congenital cardiac disease

A recent, randomised, double-blind, placebo-controlled trial has demonstrated the effectiveness of palivizumab (Synagis) for prophylaxis against infection by the respiratory syncytial virus in 1,287 young children with congenital cardiac disease. Guidelines for the use of palivizumab in these children considered to be at high risk were published by the American Academy of Pediatrics, followed by similar guidelines from the British Paediatric Cardiac Association, and recommendations from a number of other individual countries, including Canada, Germany, Spain, and France. In May, 2004, further discussion was held between a group of 15 paediatric cardiologists at a European forum for clinical management held in Munich, Germany. The objective of this forum was to define optimal recommendations on prevention of infection by the respiratory syncytial virus in infants and young children with congenital cardiac disease, appropriate to the clinical needs and style of those practising in paediatrics in individual countries. Participants were invited because of their knowledge of the therapeutic area, and for their experience of using palivizumab for prophylaxis against the respiratory syncytial virus in children with congenitally malformed hearts. Measures to educate the carers of children with such congenital malformations on precautions against infection by the respiratory syncytial virus were discussed, along with the many different aspects of best practice for therapeutic prophylaxis with palivizumab. The most appropriate timing of prophylaxis, recommendations for which children are most likely to benefit from prophylaxis, and suggested protocols were among the issues covered. The recommendations resulting from the discussions are presented in this paper, as a step towards reaching consensus.

Infection by the respiratory syncytial virus in infants and young children at high risk

The respiratory syncytial virus is the most common cause of infection of the lower respiratory tract in infants and young children, and is the leading cause of hospitalisation and death due to viral illness during the first year of life. In otherwise healthy infants, the virus usually causes only mild respiratory illness, but premature babies and infants with chronic lung disease, those with congenitally malformed hearts, or those who are immunodeficient, are at increased risk of serious illness, hospitalisation, and death. Recent infection with the virus is also associated with increased postoperative complications after corrective surgery for congenitally malformed hearts. No effective vaccine is currently available, and treatment is limited to supportive therapy. Prevention in groups deemed to be at high-risk, therefore, is essential. In addition to measures for control of infection, prophylactic immunotherapy is indicated in selected patients. Palivizumab (Synagis) is a monoclonal antibody indicated for the prevention of serious viral disease of the lower respiratory tract in premature infants, those with chronic lung disease, and those with haemodynamically significant congenital cardiac lesions. Palivizumab is given intramuscularly, usually as a monthly injection during the so-called "season". In a recent international, randomised, double-blind, placebo-controlled trial in 1,287 children less than or equal to 2 years old with haemodynamically significant congenital cardiac malformations, prophylaxis achieved a relative reduction of 45 per cent in the incidence of antigen-confirmed viral-related hospitalisation, and reduced the duration of hospital stay by 56 per cent. National and international guidelines, therefore, now recommend routine prophylaxis in the first year of life in children with haemodynamically significant congenital cardiac disease.