[Morbidity and the economic burden of influenza in children in Israel--a clinical, virologic and economic review].
BACKGROUND
A survey of winter morbidity revealed a high incidence of childhood influenza. A clinical, virologic and economic survey of childhood influenza morbidity was conducted to characterize this morbidity.


METHODS
Incidence of respiratory disease and influenza-like symptoms was determined among 9,300 children in the Tel Aviv area in the 1997-8 influenza season, and viral cultures performed from nasal swabs. A telephone survey was conducted among the patients' families to determine the family dynamics of the illness and the number of working days lost.


RESULTS
Among the study population, 38% had influenza-like symptoms. The highest incidence was among kindergarten and school-age children. Upper respiratory tract infections (URTI) were common in the 0-2 years age group (27.4%). In contrast, 83% of children with influenza-like illness (ILI) were aged 3-15 years (p < 0.01). Of 180 valid viral culture samples, 93 (51%) were positive for influenza, which represents 22% of all children surveyed. Extrapolation to a national level reveals that of approximately two million children in the country, 440,000 would have positive laboratory evidence of influenza infection. In 49 of 52 (90%) families surveyed, the child was the initial patient in the household, and, on average, 66% of family members became ill. The average income lost was NIS 300 per family; at a national level that extrapolates to a loss of NIS 132 million.


CONCLUSIONS
Influenza-like illness is common among children, particularly in the peak period of influenza activity. As opposed to upper respiratory infections, influenza-like disease is particularly common in the 3-15 year age group (kindergarten and school age). The incidence of children diagnosed with influenza (22%) is much higher than in the general population. Children are the first in the family to become ill and infect other family members. Cost-effectiveness analysis justifies mass childhood influenza immunization.
Kiro
Amnon
A
KH Sick Fund, Tel Aviv District. amnon.kiro@telaviv.health.gov.il
Robinson
Gary
G
Laks
Josef
J
Mor
Zohar
Z
Varsano
Noemi
N
Mendelson
Ella
E
Amitai
Ziva S
ZS
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D017281:Cost of Illness; D006801:Humans; D015994:Incidence; D007223:Infant; D009980:Influenza A virus / Q000145:classification / Q000302:isolation & purification; D007251:Influenza, Human / Q000191:economics / Q000453:epidemiology* / Q000635:transmission; D007557:Israel / Q000453:epidemiology