Correction to: Nature Microbiology https://doi.org/10.1038/s41564-017-0060-z, published online 20 November 2017.

In the version of this Letter originally published, technical problems led to errors in Figs. 3e and 4f. In Fig. 3e, the bottom right graph had an incorrect title of ‘CD8+ T cells’; it should have instead been ‘CD4+ T cells’. In Fig. 4f, the bottom panels had an incorrect title of ‘CD8 competent Ifnar–/– 7 d.p.i. cerebral cortex’; it should have instead been ‘CD8 depleted Ifnar–/– 7 d.p.i. cerebral cortex’. These errors have now been corrected in all versions of the Letter.