Figure 1.

The course of human disease during tick-borne flavivirus (TBFV) encephalitis relative to a healthy baseline. Viral burden is indicated by the red line; note that no distinction is made between peripheral viremia (i.e., during the first phase of disease) and viral replication in the central nervous system (i.e., during the second phase of disease). Blood-brain barrier integrity is indicated by the green line, and notably does not decline until after viremia in the CNS has begun. The T cell response is indicated by the blue line, and the distinction between effector T cells (Eomes⁺Ki-67⁺T-bet⁺) and central memory (Eomes^-Ki-67^-T-bet⁺) is highlighted (see Blom, 2018, 30319632). Note that a low frequency of memory cells persists following CNS viral replication and symptoms. Created with BioRender.com (accessed on 31 January 2023).