Neurologic Alterations Due to Respiratory Virus Infections

Bohmwald, Karen; Gálvez, Nicolás M. S.; Ríos, Mariana; Kalergis, Alexis M.

A case report of HCoV-OC43 detection in nasopharyngeal and CSF samples from a child patient was performed the year 2004 (Yeh et al., 2004) . The child exhibited acute disseminated encephalomyelitis, a low-prevalence CNS disease that induces demyelination, being this the first case related with HCoV. No other infectious agents were detected in any of the samples (Yeh et al., 2004) . Following this, a brief characterization of the cytokine profile in the CNS, induced by SARS-CoVinfection, was published. Therein, the authors indicated that both chemokine induced by IFN-γ (CXCL9, a CXC chemokines family member) and IFN-γ-inducible protein 10 (CXCL10) were highly induced in brain samples from a deceased patient (Xu et al., 2005 ; Figure 3) . However, there are reports about high levels of CXCL10 in SARS-CoV infected patients, with no neurological manifestations. Therefore the authors suggest that CXCL9 could be closely related to CNS infection (Xu et al., 2005) . Remarkably, they also showed there that peripheral blood lymphocytes and eosinophils counts in CNS-HCoV-infected patients were lower when compared with respiratory-HCoV-infected patients, while the opposite trend was observed for neutrophils (Li et al., 2016) . These differences in the recruitment of immune cells could be related to the immune response elicited by the virus, either it is respiratory-restricted or exhibits neurotropism capabilities (Li et al., 2016) .