Surveillance of equine influenza viruses through the RESPE network in F rance from N ovember 2005 to O ctober 2010

Summary Reasons for performing the study The Réseau d' E pidémio‐ S urveillance en P athologie E quine ( RESPE , the F rench epidemiological network for equine diseases) is a network for epidemio‐surveillance of major equine diseases based around sentry veterinarians in F rance. Objective The aim of this study was to evaluate the contribution of RESPE to efficient surveillance of equine influenza virus ( EIV ) in F rance. Study design Retrospective cross‐sectional study. Methods From N ovember 2005 to O ctober 2010, epidemiological and phylogenetic studies were performed on 1426 nasopharyngeal swabs received at the F rank D uncombe L aboratory. Detection was performed by real‐time reverse transcription polymerase chain reaction using original primers and probes designed in the matrix protein gene. Phylogenetic analysis was carried out on the HA 1 part of haemagglutinin gene amplified from 47 positive‐testing samples. Epidemiological information was provided with the majority of samples submitted through RESPE . Results Of the 920 samples submitted by RESPE ‐associated veterinarians, 121 (13.1%) from 42 premises were positive for EIV , compared to 26 (5.1%) of the 607 samples received from non‐ RESPE associated veterinarians. The most extensive outbreak was observed between F ebruary and M ay 2009, affecting 70 horses on 23 premises, 15 of which were managed by RESPE ‐associated veterinarians. All strains belonged to the A merican lineage, F lorida sublineage, C lade 1 and C lade 2. Clade 1 was identified only during the G rosbois episode. Conclusion RESPE improved detection of EIV in F rance, enabled characterisation of the virus strains, yielded valuable information relating to the epidemiology of the disease and identified vaccine breakdown. Potential relevance Implementation of a similar surveillance network in other countries may reduce the economic losses associated with outbreaks of EIV . The Summary is available in C hinese ‐ see Supporting information.