Trends for influenza-related deaths during pandemic and epidemic seasons, Italy, 1969-2001.
Age-specific patterns of death from influenza vary, depending on whether the influenza season is epidemic or pandemic. We assessed age patterns and geographic trends in monthly influenza-related deaths in Italy from 1969 through 2001, focusing on differences between epidemic and pandemic seasons. We evaluated age-standardized excess deaths from pneumonia and influenza and from all causes, using a modified version of a cyclical Serfling model. Excess deaths were highest for elderly persons in all seasons except the influenza A (H3N2) pandemic season (1969-70), when rates were greater for younger persons, confirming a shift toward death of younger persons during pandemic seasons. When comparing northern, central, and southern Italy, we found a high level of synchrony in the amplitude of peaks of influenza-related deaths.
Rizzo
Caterina
C
Istituto Superiore di Sanità, CNESPS, Rome, Italy. caterina.rizzo@iss.it
Bella
Antonino
A
Viboud
Cécile
C
Simonsen
Lone
L
Miller
Mark A
MA
Rota
Maria Cristina
MC
Salmaso
Stefania
S
Ciofi degli Atti
Marta Luisa
ML
D017677:Age Distribution; D000367:Age Factors; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000472:pathogenicity; D053122:Influenza A Virus, H3N2 Subtype / Q000472:pathogenicity; D009981:Influenza B virus / Q000472:pathogenicity; D007251:Influenza, Human / Q000401:mortality*; D007558:Italy / Q000453:epidemiology; D009026:Mortality / Q000639:trends*; D011159:Population Surveillance; D012621:Seasons