Chronic and delayed neurological manifestations of persistent infections

Abstract

Purpose of the review Persistent infections capable of causing central nervous system (CNS) complications months or years after the initial infection represent a major public health concern. This concern is particularly relevant considering the ongoing coronavirus disease 2019 pandemic, where the long-term neurological effects are still being recognized. Recent findings Viral infections are a risk factor for the development of neurodegenerative diseases. In this paper, we provide an in-depth exploration of the prevalent known and suspected persistent pathogens and their epidemiological and mechanistic links to later development of CNS disease. We examine the pathogenic mechanisms involved, including direct viral damage and indirect immune dysregulation, while also addressing the challenges associated with detecting persistent pathogens. Summary Viral encephalitis has been closely associated with the later development of neurodegenerative diseases and persistent viral infections of the CNS can result in severe and debilitating symptoms. Further, persistent infections may result in the development of autoreactive lymphocytes and autoimmune mediated tissue damage. Diagnosis of persistent viral infections of the CNS remains challenging and treatment options are limited. The development of additional testing modalities as well as novel antiviral agents and vaccines against these persistent infections remains a crucial research goal.

Microbes and Mental Illness: Past, Present, and Future

“…Persistent symptoms may include fatigue, post-exertional malaise, and multiple emotional and cognitive impairments (memory impairment, attention deficits, cognitive difficulties, executive dysfunction) [ 422 ]. In addition to cognitive deficits, mental symptoms include anxiety, depression, mood swings, bipolar/manic episodes, obsessive–compulsive disorders, posttraumatic stress, new-onset psychosis, sleep disturbances, substance use disorders, suicidality, and symptom constellations consistent with pediatric acute-onset neuropsychiatric syndrome (PANS; see Section 3.8.5 for additional PANS information) [ 5 , 50 , 81 , 82 , 83 , 84 , 85 , 422 , 425 , 426 , 427 , 428 , 429 , 430 , 431 , 432 ]. One retrospective cohort study using electronic health record data comprising 81 million patients in healthcare organizations primarily in the US showed that the risk of common neuropsychiatric disorders (mood disorders, anxiety disorders) returned to baseline in 1–2 months, but there remained an elevated risk of psychotic disorders, cognitive deficit, dementia, and seizures at two years of follow-up [ 83 ].…”