Herpesvirus infections and the risk of dementia

Summary Infections are increasingly recognized as risk factors for neurodegenerative diseases, including dementia. Epidemiological studies indicate that both systemic infections and infections outside the central nervous system, as well as infections with neurotropic pathogens, can increase the risk of cognitive decline and dementia. Among these, herpes simplex viruses 1 and 2 and varicella zoster virus have been studied extensively. These viruses establish lifelong latency in neurons and can reactivate over the course of time. Epidemiological studies have reported positive correlations between herpesvirus infections or reactivations and the incidence of dementia. Moreover, antiviral treatments and vaccinations appear to confer protective effects in this context. Preclinical studies provide mechanistic insights, suggesting potential causal links between herpesvirus infections and neurodegeneration, including the development of specific neuropathological changes. Further research is needed to fully understand these mechanisms and to uncover the potential for additional preventive strategies against dementia.