The burden of influenza illness in children with asthma and other chronic medical conditions.
OBJECTIVE
Although influenza immunization is recommended for children with high-risk medical conditions, the majority of such children do not receive influenza vaccine. This study was designed to measure the burden of influenza among children with asthma and other chronic medical conditions.


METHODS
We performed a retrospective cohort study of children younger than 15 years with medically treated asthma or other chronic medical conditions enrolled in the Tennessee Medicaid program from 1973 to 1993. We determined rates of hospitalization for acute cardiopulmonary disease, outpatient visits, and antibiotic courses throughout the year. Annual differences between event rates when influenza virus was circulating and event rates during winter months when there was no influenza in the community were used to calculate influenza-attributable morbidity.


RESULTS
Influenza accounted for an average of 19, 8, and 2 excess hospitalizations for cardiopulmonary disease yearly per 1000 high-risk children aged <1 year, 1 to <3 years, and 3 to <15 years, respectively. For every 1000 children, an estimated 120 to 200 outpatient visits and 65 to 140 antibiotic courses were attributable to influenza annually.


CONCLUSIONS
Children younger than 15 years with asthma and other chronic medical conditions experience substantial morbidity requiring inpatient and outpatient care during influenza season. More effective targeting of this population for annual influenza immunization is warranted.
Neuzil
K M
KM
Department of Medicine, University of Washington School of Medicine, Seattle, Washington, USA.
Wright
P F
PF
Mitchel
E F
EF
Griffin
M R
MR
D000293:Adolescent; D000553:Ambulatory Care / Q000706:statistics & numerical data; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001249:Asthma / Q000150:complications* / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D015331:Cohort Studies; D017281:Cost of Illness; D004363:Drug Utilization; D005260:Female; D006331:Heart Diseases / Q000150:complications* / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007252:Influenza Vaccines; D007251:Influenza, Human / Q000150:complications* / Q000453:epidemiology / Q000517:prevention & control; D008171:Lung Diseases / Q000150:complications* / Q000453:epidemiology; D008297:Male; D009017:Morbidity; D012189:Retrospective Studies; D012621:Seasons; D013714:Tennessee / Q000453:epidemiology
D000900:Anti-Bacterial Agents; D007252:Influenza Vaccines