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Published on: August 14, 2019
Hospitalized children with influenza A H1N1 (2009) infection: a Spanish multicenter study
Susanna Hernández-Bou1, Cristina Borrás Novell, Jara Guardia Alins
1Pediatric Emergency Department, Hospital Sant Joan de Déu Barcelona, Spain. shernandez@hsjdbcn.org
Insights
Severe complications from influenza A H1N1 (2009) occurred in Spanish children, with bacterial coinfection increasing the risk of intensive care. While most cases resolved favorably, some pediatric patients experienced significant illness and mortality.
Area of Science:
- Pediatric Infectious Diseases
- Virology
- Epidemiology
Background:
- Influenza A H1N1 (2009) can cause severe complications in children, despite most cases being mild.
- Understanding pediatric complications is crucial for public health management.
Purpose of the Study:
- To describe the complications of influenza A H1N1 (2009) in the pediatric population in Spain.
- To identify risk factors associated with severe outcomes in children.
Main Methods:
- Multicenter descriptive study of hospitalized children (<14 years) with confirmed influenza A H1N1 (2009).
- Data collected on demographics, risk factors, clinical presentation, treatment, and outcomes.
- Analysis of factors associated with intensive care unit (ICU) admission.
Main Results:
- 308 children were included; hospitalization rate was 20.5/100,000.
- Bacterial pneumonia was the most common admission diagnosis (42.5%).
- 17.5% required ICU admission, and 1.9% died; confirmed bacterial coinfection (9.4%) was linked to ICU need (OR 3.3).
Conclusions:
- Respiratory manifestations were the primary complications.
- A significant burden of morbidity and mortality was observed in this pediatric cohort.
- Confirmed bacterial coinfection is a key risk factor for severe influenza A H1N1 (2009) illness in children.
Objectives:
Even though the majority of cases of influenza A H1N1 (2009) in children are mild, severe complications have been reported. Our objective was to describe the Influenza A H1N1 (2009) complications in pediatric population in Spain.
Methods:
This was a multicenter descriptive study including patients younger than 14 years attending 15 emergency departments and hospitalized with laboratory-confirmed influenza A H1N1 (2009) infection from August to December 2009. Patients who did not meet any of the admission criteria recommended by the Health Spanish Authorities were excluded. A standardized report form was used to collect information on demographics, risk factors, clinical and microbiological data, treatment, and outcome. Potential risk factors associated with intensive care requirement (assisted ventilation and/or inotropic support) were analyzed.
Results:
Three hundred eight patients were included. The hospitalization rate was 20.5 per 100,000 children younger than 14 years. Median age was 48 months; 21% had underlying medical conditions. The most common diagnosis at admission was presumed bacterial pneumonia (42.5%). Oseltamivir was prescribed on admission to 207 children (67.2%) and antibiotics to 199 (64.6%). Bacterial coinfection was confirmed in 29 patients (9.4%). Fifty-four patients (17.5%) were admitted to an intensive care unit, and 6 (1.9%) died. Logistic regression model revealed that confirmed bacterial coinfection was associated with intensive care requirement (odds ratio, 3.3; 95% confidence interval, 1.1-10.0).
Conclusions:
Respiratory manifestations were the main complication described. Although the majority of patients had a favorable evolution, a remarkable morbidity and mortality were observed. Patients with confirmed bacterial coinfection were at high risk of severe illness.
