***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The national observational multicenter cohort study presented here was conducted over two respiratory syncytial virus ( RSV ) seasons ( 2001–2003 ) in Austria to collect data on  RSV-related rehospitalizations in premature infants of 29 –32-weeks ’ gestational age . The results revealed an overall RSV hospitalization rate of 4.5 % ( 36/801 ) . Risk factors were discharge from the neonatal intensive care unit between the months of October and December , birth between June and December 2002 , and neurological disease . Palivizumab prophylaxis was given to 238 ( 29.7 % ) infants , and 148 infants received inadequate or incomplete courses . Respiratory syncytial virus ( RSV ) infection represents a major cause of rehospitalization during the first year of life in preterm infants [ 1 ] . Recommendations for RSV prophylaxis with palivizumab [ 2 ] have been adopted without major modifications in Austria [ 3 ] , and they suggest that decisions regarding this drug ’s administration should be based on local epidemiological data . Currently , very limited data are available on the risk of RSV-related rehospitalization in Austria [ 4 ] . Due to the fact that insurance companies allocate and reimburse prophylaxis with palivizumab in this group of premature infants differently from published recommendations and with great local variation , we initiated a nationwide observational cohort study . The study was aim ed at collecting data on  RSV-related rehospitalization of premature infants of 29–32-weeks ’ gestational age in order to analyze associated risk factors and to assess the use of palivizumab prophylaxis in this population . Infants were included if their gestational age was between 29 ( 29 + 0 ) and 32 ( 32 + 6 ) weeks and if they were born between 1 June 2001 and 31 December 2002 . All infants were followed up until 1 June 2003 . For the first RSV season , data on all rehospitalizations were collected retrospectively from medical charts and by telephone calls : for the second RSV season , which occurred after the study was initiated in February 2002 , data were collected prospect ively . In cases of rehospitalization due to respiratory illness , the following data were collected : patient age in months , the month in which rehospitalization occurred , severity of respiratory illness ( determined using the modified clinical lower respiratory illness/infection score [ 5 ] ) , length of stay , number of days with supplemental oxygen , number of days at the intensive care unit , and number of days with mechanical ventilation including nasal continuous positive airway pressure . RSVantigen detection was performed on nasopharyngeal aspirates using either enzyme-linked immunosorbent assays or immunofluorescence techniques . Viral cultures were not performed . Prophylaxis with monthly administered intramuscular injections of palivizumab was usually started at the end of October or beginning of November , with the last injection in March . Recommendations for prophylaxis were influenced by local differences in allocation and reimbursement of prophylaxis by the insurance companies . Prophylaxis administration was not influenced by the study protocol . The study was approved by the local ethics committee , and informed consent was given by the parents of those infants prospect ively enrolled into the study . Statistical analyses were performed using the Pearson chi-square and Yate ’s corrected chi-square test , as appropriate for categorical data , and the t-test and Fisher ’s exact test , as appropriate for numerical data . Multivariate analysis was performed using a logistic regression model with backward elimination and the Wald criterion . Analysis was done with SPSS ( SPSS , Chicago , IL , USA ) , and StatXact4 ( Cytel , Cambridge , MA , USA ) software . B. Resch ( * ) . W. Gusenleitner . W. D. Muller Division of Neonatology , Department of Paediatrics , Medical University Graz , Auenbruggerplatz 30 , 8036 Graz , Austria e-mail : bernhard.resch@meduni-graz.at Tel . : + 43 - 316 - 3852605 Fax : + 43 - 316 - The Palivizumab Outcomes Registry collected data on 19,548 high-risk infants who received ≥1 dose of palivizumab and followed prospect ively from 2000 through 2004 . Ninety-one children with cystic fibrosis ( CF ) were identified who received palivizumab off label . None of the infants with CF who received prophylaxis was hospitalized as a result of respiratory syncytial virus lower respiratory tract infection . Evaluations of palivizumab use in infants with CF could be warranted BACKGROUND Bronchiolitis caused by respiratory syncytial virus ( RSV ) is an important cause of morbidity in ex-premature infants . In a r and omised placebo controlled trial monoclonal antibody prophylaxis showed a 55 % reduction in relative risk of hospital admission for these high risk infants , against a background incidence of 10.6 admissions per 100 high risk infants . AIMS To follow a cohort of high risk infants in order to assess hospitalisation rate from RSV and the potential impact of prophylaxis for these patients in a UK local health authority . METHODS A cohort of high risk infants from a local health authority were followed over the 1998/99 and 1999/2000 RSV seasons . The high risk population was defined as infants who , at the beginning of the seasons studied , were : ( 1 ) under 6 months old and born prior to 36 weeks gestation with no domiciliary oxygen requirement ; or ( 2 ) under 24 months of age and discharged home in supplemental oxygen . All admissions with bronchiolitis during the season were identified . RESULTS A total of 370 high risk infants were identified for the 1998/99 season and 286 for the following year . Over the two years there were 68 admissions . Significantly more admissions occurred from group 2 infants . RSV was identified in 27 cases ( four admissions per hundred high risk infants ) . Prophylaxis may have saved up to £ 195 134 in hospital costs over the two years , but would have cost £ 1.1 million in drug acquisition costs . CONCLUSIONS Careful consideration of risk factors is needed when selecting infants for RSV prophylaxis Limited data in children with cystic fibrosis ( CF ) suggest that respiratory viral infections during infancy result in substantial morbidity .  Eighty of 101 ( 79 % ) infants with CF diagnosed by neonatal screening during 1991 - 1996 were recruited into a prospect i ve , multiple-birth cohort study . We aim ed to perform an initial , then annual bronchoalveolar lavage ( BAL ) for bacterial and viral culture , cytology , IL-8 , and elastolytic activity over the following 2 years . When possible , BAL was also performed during any hospitalization for a pulmonary exacerbation , and additional specimens for viral culture were collected by nasopharyngeal aspiration . Thirteen infants undergoing bronchoscopy for congenital stridor served as disease controls . During infancy , 31 children ( 39 % ) were hospitalized for respiratory disease and 20 ( 65 % ) cases had an etiologic agent identified . Respiratory viruses were detected in 16/31 ( 52 % ) cases , including four with simultaneous bacterial infection . Another four were infected with Staphylococcus aureus . Respiratory syncytial virus predominated and was found in seven infants . In the absence of bacteria , those with viral infections had acute onset of respiratory distress , were not treated with antibiotics , and had an uncomplicated hospital course . Compared to noninfected CF subjects and controls , infected infants had elevated BAL inflammatory indices ( P < 0.01 ) . Eleven of 31 ( 35 % ) hospitalized infants followed for 12 - 60 months acquired Pseudomonas aeruginosa , compared with only three of 49 ( 6 % ) subjects not hospitalized for respiratory symptoms during infancy ( risk ratio 5.8 , CI 1.9 , 24 ) . We conclude that respiratory viruses are important causes of hospitalization in CF infants . While viral infections were self-limited , they were accompanied by airway inflammatory changes , and admission to hospital was associated with early acquisition of Pseudomonas aeruginosa and persistent respiratory symptoms The present study was design ed to determine the efficacy of administration of palivizumab to preterm infants with gestational age ( GA ) < or = 30 weeks without bronchopulmonary dysplasia ( BPD ) . All patients born with GA < or = 30 weeks without BPD on Day 28 and hospitalized for RSV bronchiolitis in Burgundy ( 12 hospitals ) from December 1 to April 30 of the next year were included in this prospect i ve observational study during five successive RSV seasons ( 1999 - 2000 , 2000 - 2001 , 2001 - 2002 , 2002 - 2003 , and 2003 - 2004 ) . Palivizumab was given to premature infants with a gestational age < or = 30 weeks without BPD in the 2002 - 2003 and 2003 - 2004 periods only . In the cohort of premature infants with GA < or = 30 weeks without BPD , the respiratory syncytial virus ( RSV ) bronchiolitis hospitalization rate was reduced significantly ( P < 0.01 ) in the two seasons with palivizumab prophylaxis ( 2002 - 2003 : 0 % and 2003 - 2004 : 2 % ) versus the three previous RSV seasons ( 1999 - 2000 : 14.3 % ; 2000 - 2001 : 16.7 % ; 2001 - 2002 : 10.2 % ) . The number needed to treat to prevent one hospitalization for RSV bronchiolitis was 6 ( 95%CI : 4 - 11 ) . Such favorable results have not been always found in the few available postmarketing epidemiological studies on hospitalization rate after palivizumab prophylaxis . Differences in health care organization could explain those discrepancies Aims : To determine the frequency of and the risk factors for readmissions for any lower respiratory tract illness ( LRTI ) and for respiratory syncytial virus ( RSV ) documented LRTI in children born very prematurely who had or had not received RSV prophylaxis . Methods : Multicentre prospect i ve longitudinal cohort study of 2813 infants , born between April 2000 and December 2000 at less than 33 weeks of gestational age , and followed until the end of the epidemic season . Results : Among the 2256 children who had no bronchopulmonary dysplasia at 36 weeks of postmenstrual age and were not su bmi tted to RSV prophylaxis  , 27.4 % were readmitted at least once for any reason during the epidemic season ; 15.1 % and 7.2 % were readmitted at least once for any LRTI and RSV related LRTI , respectively . Children born at less than 31 weeks ’ gestation , having an intrauterine growth restriction , or living in a single mother family were at a significantly higher risk of readmission for LRTI in general as well as for RSV related LRTI . Of the 376 children su bmi tted to prophylaxis , 28.2 % were readmitted at least once for any LRTI and 6.1 % for RSV related LRTI . Conclusion : One out of four children who had received no prophylaxis , was born very prematurely , and was without bronchopulmonary dysplasia at 36 weeks of postmenstrual age , was readmitted at least once for any reason . Roughly 50 % and 20 % of these readmissions were related to a LRTI and an RSV infection , respectively . Further epidemiological studies are warranted to assess the aetiology and impact of other respiratory pathogens on post-discharge readmission and respiratory morbidity in this population BACKGROUND In Japan , palivizumab was approved in 2002 for prophylaxis of severe respiratory syncytial virus disease in high-risk infants . In order to evaluate the efficacy and safety of this drug , a question naire survey was conducted . METHODS A question naire was sent to member institutions of the Japan Neonatologist Association . The subjects were premature infants who were considered possible c and i date s for treatment with palivizumab .  RESULTS A total of 6302 case reports , including those of 2806 infants receiving palivizumab ( group P ) and 3496 infants not receiving palivizumab ( group NP ) , respectively , were retrieved . Background characteristics revealed significant lower gestational age ( GA ) and birthweight for group P ( P < 0.0001 ) . Sex ratio did not differ significantly , while use of oxygen and mechanical ventilation in the neonatal intensive care unit , and presence of chronic lung disease were significantly higher for infants in group P ( P < 0.0001 ) . When comparison of hospitalization rate for respiratory symptoms was performed with stratification by eligibility criteria , in the group of infants born at 29 - 35 weeks GA the hospitalization rate was 4.0 % and 5.7 % in groups P and NP , respectively ( P < 0.05 ) . Multivariate analysis also showed that pro 
    Output:
    
This review supports the recommended use of palivizumab for reducing RSV-associated hospitalization rates in premature infants born at gestational age < 33 weeks and in children with chronic lung and heart diseases .