@article{fdi:010054351,
  title = {{S}erological study of the 2009 pandemic due to influenza {A} {H}1{N}1 in the metropolitan {F}rench population},
  author = {{D}elangue, {J}. and {S}alez, {N}. and {N}inove, {L}. and {K}ieffer, {A}. and {Z}andotti, {C}. and {S}eston, {M}organ and {L}ina, {B}. and {N}ougairede, {A}. and {C}harrel, {R}. and {F}lahault, {A}. and {D}e {L}amballerie, {X}avier},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e looked for evidence of antibodies to the 2009 influenza {A}/{H}1{N}1 pandemic virus in panels of sera from individuals living in metropolitan {F}rance, obtained either before, during or after the epidemic, using standard haemagglutination inhibition and microneutralization tests. {T}he difference between seroprevalence values measured in post- and pre-epidemic panels was used as an estimate of seroconversion rate in different age groups (23.4% (024 years, age-group 0); 16.5% (2534); 7.9% (3544); 7.2% (4554); 1.6% (5564); and 3.1% (>65)), confirming that the distribution of cases in different age groups was similar to that of the seasonal {H}1{N}1 virus. {D}uring the pre-pandemic period low-titre cross-reactive antibodies were present in a large proportion of the population (presumably acquired against seasonal {H}1{N}1) whereas cross-reactive antibodies were detected in individuals over the age of 65 years with significantly higher prevalence and serological titres (presumably acquired previously against {S}panish flu-related {H}1{N}1 strains). {C}linical data and analysis of post-pandemic seroprevalence showed that few of these latter patients were infected by the influenza virus during the epidemic. {I}n contrast, the majority of both clinical cases and seroconversions were recorded in the 024 age group and a global inverse relationship between prevalence of antibodies to p{H}1{N}1 in the pre-pandemic period and rate of seroconversion was observed amongst age groups. {O}ur results emphasize the complex relationships involved in antigenic reactivity to pandemic and seasonal {H}1{N}1 viral antigens; hence the difficulty in distinguishing between low-titre specific and cross-reactive antibodies, establishing precise seroprevalence numbers and fully understanding the relationship between previous immunity to seasonal viruses and protection against the novel variant.},
  keywords = {{E}pidemiology ; {H}1{N}1 ; haemagglutination ; microneutralization ; pandemic ; seroconversion ; {FRANCE}},
  booktitle = {},
  journal = {{C}linical {M}icrobiology and {I}nfection},
  volume = {18},
  numero = {2},
  pages = {177--183},
  ISSN = {1198-743{X}},
  year = {2012},
  DOI = {10.1111/j.1469-0691.2011.03545.x},
  URL = {https://www.documentation.ird.fr/hor/fdi:010054351},
}