Children hospitalized with 2009 novel influenza A(H1N1) in California.

Abstract

OBJECTIVE:

To describe clinical and epidemiologic features of 2009 novel influenza A(H1N1) in children.

DESIGN:

Analysis of data obtained from standardized report forms and medical records.

SETTING:

Statewide public health surveillance in California.

PARTICIPANTS:

Three hundred forty-five children who were hospitalized with or died of 2009 novel influenza A(H1N1).

MAIN EXPOSURE:

Laboratory-confirmed 2009 novel influenza A(H1N1).

MAIN OUTCOME MEASURES:

Hospitalization and death.

RESULTS:

From April 23 to August 11, 2009, 345 cases in children younger than 18 years were reported. The median age was 6 years. The hospitalization rate per 100 000 per 110 days was 3.5 (0.97 per 100 000 person-months), with rates highest in infants younger than 6 months (13.9 per 100 000 or 3.86 per 100 000 person-months). Two-thirds (230; 67%) had comorbidities. More than half (163 of 278; 59%) had pneumonia, 94 (27%) required intensive care, and 9 (3%) died; in 3 fatal cases (33%), children had secondary bacterial infections. More than two-thirds (221 of 319; 69%) received antiviral treatment, 44% (88 of 202) within 48 hours of symptom onset. In multivariate analysis, congenital heart disease (odds ratio [OR], 5.0; 95% confidence interval [CI], 1.9-13.5) and cerebral palsy/developmental delay (OR, 3.5; 95% CI, 1.7-7.4) were associated with increased likelihood of intensive care unit admission and/or death; likelihood was decreased in Hispanic (OR, 0.4; 95% CI, 0.2-0.8) and black (OR, 0.3; 95% CI, 0.1-1.0) children compared with white children.

CONCLUSIONS:

More than one-quarter of children hospitalized with 2009 novel influenza A(H1N1) reported to the California Department of Public Health required intensive care and/or died. Regardless of rapid test results, when 2009 novel influenza A(H1N1) is circulating, clinicians should maintain a high suspicion in children with febrile respiratory illness and promptly treat those with underlying risk factors, especially infants.

• Authors: Janice K Louie, Shilpa Gavali, Meileen Acosta, Michael C Samuel, Kathleen Winter, Cynthia Jean, Carol A Glaser, Bela T Matyas, Robert Schechter, California Pandemic (H1N1) Working Group
• Journal: Archives of pediatrics & adolescent medicine (Arch Pediatr Adolesc Med) Vol. 164 Issue 11 Pg. 1023-31 (Nov 2010) ISSN: 1538-3628 [Electronic] United States
• PMID: 21041595 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antiviral Agents

Topics

• Adolescent
• Antiviral Agents (therapeutic use)
• California (epidemiology)
• Child
• Child, Preschool
• Comorbidity
• Critical Care (statistics & numerical data)
• Female
• Hospital Mortality
• Hospitalization (statistics & numerical data)
• Humans
• Infant
• Influenza A Virus, H1N1 Subtype
• Influenza, Human (complications, epidemiology, therapy, virology)
• Male
• Population Surveillance
• Risk Factors