Epidémiologie clinique et virologique de la bronchiolite du nourrisson. Enquête nationale multicentrique (I)

Economic and disease burden of RSV-associated hospitalizations in young children in France, from 2010 through 2018

BACKGROUND

Respiratory syncytial virus (RSV) is the main cause of infant and child hospitalizations. The study objective is to estimate the RSV-associated hospitalizations and economic burden in young children in France to inform future preventive strategies.

METHODS

We conducted a retrospective analysis of RSV-associated hospitalizations data from the French Hospital database (PMSI-MCO) which covers the entire French population. All children aged < 5 years hospitalized with RSV ICD-10 codes (J210, J219, J45, J121, J205, R062) from 2010 to 2018, were included. Descriptive analyses were conducted by RSV seasons (Oct to March), by respiratory years (July to June) and per age groups.

RESULTS

On average 45,225 RSV-associated hospitalizations (range: 43,715 - 54,616) per season was reported in France, 69% among children < 1 year old. This represents 28% of all-cause hospitalizations that occurred among children < 1 year old, and less than 10% of all-cause hospitalizations in older children. Number of RSV-associated hospitalizations were similar for infants born during (Oct-March) or outside (April-September) their first RSV season. The highest risk being reported for infants born from September through November. The associated hospitalization cost increased between 2010 - 11 and 2017-18, from €93.2 million to €124.1 million, respectively, and infants < 1 year old represented 80% of the economic burden.

CONCLUSION

RSV is an important cause of child hospitalization in France. The burden on healthcare system is mainly driven by < 1 year olds, and preventive strategies should be implemented before the first RSV season.

[Prospective regional study of an epidemic of respiratory syncytial virus (RSV) bronchiolitis]

This prospective study was designed to identify risk factors associated with admission in pediatric intensive care units (PICU) among infants hospitalized for treatment of RSV induced bronchiolitis. This study was population-based and was conducted in Burgundy, a French region with 1,800,000 inhabitants where passive immunoprophylaxis for RSV bronchiolitis was not set up at the time of the study.

RESULTS

From December 1st 1999 to April 30th 2000, 484 infants were hospitalized for RSV bronchiolitis in Burgundy: 19.6% were born prematurely (gestational age [GA] below 37 weeks) and at admission, 68.3% had a postnatal age below six months (mean = 5 +/- 5.9 months; median value = 3 months). The duration of hospitalization was 7.3 +/- 12.4 days (median value = 6 days). Among the 484 infants, 31 (6.4%) needed admission in PICU, eight needed mechanical ventilation (1.7%) and one died (0.2%). Univariate analysis identified anamnestic risk factors associated with admission in PICU: prematurity; low birth weight; past history of neonatal respiratory distress syndrome (RDS); mechanical ventilation for RDS treatment; bronchopulmonary dysplasia (BPD) and congenital heart disease. Multivariate analysis identified three independent factors associated with an increased risk for admission in PICU: GA below 32 weeks; RDS and congenital heart disease.

CONCLUSION

This study suggests that population at risk for severe RSV bronchiolitis with PICU admission should include all very preterm infants with RDS whatever the outcome of RDS (with or without BPD). These epidemiological data could be helpful to set up indications for passive immunoprophylaxis of RSV induced bronchiolitis.

[Epidemiology of infant bronchiolitis in France]

Respiratory syncytial virus (RSV) bronchiolitis has become a major public health concern in France during the last decade. This winter epidemic mobilizes each year considerable means through the private ambulatory and public hospital nets. The epidemiology of RSV bronchiolitis remains difficult to characterize because of the lack of consensus for its definition. Several French studies are described here which suggest an increase in severity of the epidemics since 10 years in France. Peaks are more important each year and involve younger patients. This phenomenon does not concern other winter epidemics such as rotavirus gastroenteritis or influenza in infants. A policy of prevention of RSV bronchiolitis seams to be necessary in our country in the future.

Le virus respiratoire syncytial: importance en pathologie, méthodes diagnostiques, traitement et prévention

Les bronchiolites à VRS sont fréquentes, épidémiques et nécessitent parfois l'hospitalisation des nourrissons, voire une réanimation.Le déterminisme des lésions pulmonaires est complexe, lié au virus et à la réaction immunitaire. Le traitement est symptomatique, et l'utilisation de la ribavirine est limitée aux formes sévères. Le diagnostic virologique doit être rapide, et la recherche immunologique directe des protéines virales est la technique la plus utilisée.

[Coincidental outbreaks of rotavirus and respiratory syncytial virus in Paris: a survey from 1993 to 1998]

PATIENTS AND METHODS

In a pediatric hospital of Paris, from 1993 to 1998, respiratory secretions were positive for respiratory syncytial virus (RSV) in 26.3% of 4,738 children (0-5 years) examined or hospitalized for lower respiratory tract infections. Rotavirus detection was positive in stools of 23.7% of the 8,537 children of the same age with acute diarrhea.

RESULTS

The RSV epidemic peak occurred annually in Paris in December and the rotavirus outbreak peaks were observed in December/January. The winter seasonal peaks remained constant for both pathogens and the temporal appearance of these peaks was constant from 1993 to 1998. Fifty to sixty-one percent of rotavirus and 77 to 92% of RSV infections were observed in November, December or January. These simultaneous outbreaks provoked important problems in hospital organization and prevention of nosocomial infections.

CONCLUSION

The coincidence of RSV and rotavirus peaks is not found in all countries. The epidemic patterns have to be checked in other parts of France and Europe because this could be important when active immunization programs will be available for these two pathogens.