Neurologic Alterations Due to Respiratory Virus Infections

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

Interestingly, when they evaluated the effects of IAV infections in the behavior, no virus has affected the mice anxiety or locomotor activity whereas at 30 and 120 days postinfection, however, H3N2 and H7N7-infected mice showed an impairment of spatial learning and memory (Hosseini et al., 2018) . This work proves that, unlike what is reported by Jurgens et al. (2012) -which perform cognitive test and neuron morphology experiments during the acute phase of the infection-the H1N1 infection does not lead to long-term impairment in spatial memory nor affects the neuron morphology (Hosseini et al., 2018) . The H3N2 subtype is not able to replicate in the CNS; however, it is capable of increasing the levels of TNF-α in the hippocampus and also increase the number of microglia (Hosseini et al., 2018 ; Figure 2 ). On the other hand, H7N7 not only increases the level of IFN-γ and TNF-α in the CNS but also alters the long-term potentiation (LTP) and disrupts the permeability of the BBB, promoting a stronger inflammatory immune response than H3N2 (Hosseini et al., 2018) . Based on all these data, the most important conclusion is that it is necessary to know the immune response promoted by IVs, as it has been proven that long-term alteration can be caused without CNS viral replication.