A. Hematoxylin and eosin staining of control non-infected (NF) mouse and two WNV H8912-infected mice kidney sections at day 84 post-infection; arrows in infected mouse kidney indicate focal interstitial lymphocytic collection. B–C. Sera were collected from NF and mice that were infected with WNV H8912 at day 10 (D10), day 30 (D30), day 60 (D60) and day 84 (D84) post-infection. The development of WNV-specific IgM (B) or IgG (C) antibodies was determined after incubating sera with absorbed purified r-WNV-E protein. Data are presented as means ± SEM, n = 4–12. **P<0.01 compared to NF mice. D–E. Splenocytes and kidney leukocytes were harvested at indicated time points post-infection and stained for CD8 and WNV- NS4B or WNV -E epitopes. The total numbers of WNV specific T cells were shown.