Central nervous system infections

New research shows that meningeal lymphatic vessels can drain viruses from the CNS, with important implications for our understanding of CNS infections.

Several studies indicate that, in individuals infected with herpes simplex virus and/or varicella zoster virus, antiviral therapy reduces the subsequent risk of Alzheimer disease and other types of dementia. As highlighted in this article, the preventative potential of antiviral therapy would probably be maximized by treating asymptomatic as well as symptomatic infected individuals.

The neurological deficits caused by COVID-19, which were first reported in the early months of 2020, continue to intrigue neurologists and health-care professionals worldwide. As two new studies highlight, these manifestations are frequent and are expected to increase the burden of morbidity and mortality in the acute and chronic phases of COVID-19.

In India, the peak of SARS-CoV-2 infections in May 2021 was paralleled by an outbreak of rhino-oculo-cerebral mucormycosis (ROCM) — a fungal infection affecting the nose, eyes and brain. This outbreak provided a unique opportunity to study the neurological manifestations of ROCM and to investigate new treatments for the condition.

As the COVID-19 pandemic developed and neurological manifestations were reported, concern grew that SARS-CoV-2 might directly invade neuronal cells. However, research throughout the year to address this concern has revealed a different story with inflammatory processes at its centre.