Integrative study of pandemic A/H1N1 influenza infections: design and methods of the CoPanFlu-France cohort.
BACKGROUND
The risk of influenza infection depends on biological characteristics, individual or collective behaviors and the environmental context. The Cohorts for Pandemic Influenza (CoPanFlu) France study was set up in 2009 after the identification of the novel swine-origin A/H1N1 pandemic influenza virus. This cohort of 601 households (1450 subjects) representative for the general population aims at using an integrative approach to study the risk and characteristics of influenza infection as a complex combination of data collected from questionnaires regarding sociodemographic, medical, behavioral characteristics of subjects and indoor environment, using biological samples or environmental databases.


METHODS
Households were included between December 2009 and July 2010. The design of this study relies on systematic follow-up visits between influenza seasons and additional visits during influenza seasons, when an influenza-like illness is detected in a household via an active surveillance system. During systematic visits, a nurse collects individual and environmental data on questionnaires and obtains blood samples from all members of the household. When an influenza-like-illness is detected, a nurse visits the household three times during the 12 following days, and collects data on questionnaires regarding exposure and symptoms, and biological samples (including nasal swabs) from all subjects in the household. The end of the follow-up period is expected in fall 2012.


CONCLUSIONS
The large amount of data collected throughout the follow-up will permit a multidisciplinary study of influenza infections. Additional data is being collected and analyzed in this ongoing cohort. The longitudinal analysis of these households will permit integrative analyses of complex phenomena such as individual, collective and environmental risk factors of infection, routes of transmission, or determinants of the immune response to infection or vaccination.
Institut National de la Santé et de la Recherche Médicale, UMR-S 707, F-75012 Paris, France. lapidus@u707.jussieu.fr
Nathanael
N
Lapidus
Xavier
X
de Lamballerie
Nicolas
N
Salez
Michel
M
Setbon
Pascal
P
Ferrari
Rosemary M
RM
Delabre
Marie-Lise
ML
Gougeon
Frédéric
F
Vely
Marianne
M
Leruez-Ville
Laurent
L
Andreoletti
Simon
S
Cauchemez
Pierre-Yves
PY
Boëlle
Eric
E
Vivier
Laurent
L
Abel
Michaël
M
Schwarzinger
Michèle
M
Legeas
Pierre
P
Le Cann
Antoine
A
Flahault
Fabrice
F
Carrat
D015331:Cohort Studies; D005191:Family Characteristics; D005602:France / Q000453:epidemiology; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000453:epidemiology*; D058873:Pandemics; D011159:Population Surveillance / Q000379:methods*; D012107:Research Design; D012307:Risk Factors