*4.7. Statistical Analysis*

We used negative binomial generalized linear models to analyze the mosquito trapping data. The dependent variable was the number of trapped *Cx. pipiens*, and the independent variables were the department (Bouches-du-Rhône–reference class, Gard, or Hérault) and the year (2015–2019, the reference class being 2018). Two models were separately fitted: One for the yearly total number of trapped *Cx. pipiens*, and the other for the number of *Cx. pipiens* trapped in June. Statistical analyses were performed using R 3.6.1 [72].

**Supplementary Materials:** The following are available online at http://www.mdpi.com/2076-0817/9/11/908/s1. Table S1: Table presenting percentage homology in nucleotidic (nt, upper part) and in amino acid (aa, lower part) WNV sequences. Table S2: Amino acid substitutions identified between WNV-Akela/France/2015 and older French lineage 1 isolates. Table S3: Amino acid substitutions identified between lineage 2 WNV-7025/France/2018 and the closely genetically related WNV-Cremona4/Italy/2014.

**Author Contributions:** Conceptualization, C.B., S.D., I.L.G. and S.L. (Sylvie Lecollinet); methodology, C.B., I.L.G., S.D., B.D. and S.L. (Sylvie Lecollinet); software, B.D., Y.B., P.L. and X.d.L.; validation C.B., S.D., I.L.G. and S.L. (Sylvie Lecollinet), F.F., investigation, C.B., S.D., I.L.G., G.G. (Gaelle Gonzalez), M.D., S.L. (Steeve Lowenski), P.L., G.G. (Gilda Grard), G.A.D., J.T., G.L., and S.L. (Sylvie Lecollinet), F.F.; resources C.B., I.L.G., F.F., Y.B., P.L., X.d.L., G.L., S.D. and S.L. (Sylvie Lecollinet); data curation, C.B., I.L.G., F.F., G.G. (Gaelle Gonzalez), Y.B., P.L., X.d.L., G.G. (Gilda Grard), G.A.D., G.L., B.D. and S.L. (Steeve Lowenski ); writing—original draft preparation, C.B.; writing—review and editing, C.B., I.L.G., F.F., G.G. (Gaelle Gonzalez), S.Z., G.L., B.D., S.D. and S.L. (Sylvie Lecollinet); visualization, C.B.; supervision, C.B., G.G. (Gilda Grard), I.L.G. and S.L. (Sylvie Lecollinet). All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by EU Commission through DG SANTé (EU-RL on equine diseases).

**Acknowledgments:** The authors would like to thank the local veterinary laboratories, veterinary practitioners, local hunting federations, and Office français de la Biodiversité (OFB).

**Conflicts of Interest:** The authors declare no conflict of interest.
