FIGURE 1.

The pathways through which enteroviruses can gain access to the CNS. Enteroviruses can invade the CNS through three pathways. First, they infect BMECs, compromising and crossing the BBB to reach the CNS directly. The second pathway is known as Trojan horse route, in which enterovirus-infected leukocytes act as carriers and transverse the brain barriers bringing virus into the CNS. Thirdly, enteroviruses are able to hijack the retrograde axonal transport to enter the CNS from muscles into the motor neurons in the spinal cord.