CNS Viral Infections Overview

Poliovirus is transmitted via the faecal-oral route or through contaminated food or water.

The common symptoms include a triad of fever, meningism, and vomiting.

The primary symptoms include fever, headache, nausea, sore throat, and myalgia.

<p>The primary cause of viral encephalitis is infection by viruses such as enterovirus, HSV, rabies virus, and arboviruses.</p> Signup and view all the answers

<p>Poliovirus can invade motor neurons in the spinal cord, leading to flaccid paralysis if nervous tissue is infected.</p> Signup and view all the answers

<p>Approximately 1 in 200 infections leads to irreversible paralysis.</p> Signup and view all the answers

<p>Acute flaccid paralysis (AFP) is characterized by the sudden onset of flaccid paralysis in one or more limbs, often caused by anterior horn cell infection with poliovirus or other viruses.</p> Signup and view all the answers

<p>Aseptic meningitis is characterized by an increased mononuclear cell count (pleocytosis) in the CSF, while bacterial meningitis shows a predominance of neutrophils.</p> Signup and view all the answers

<p>Post-polio syndrome (PPS) is progressive muscle deterioration occurring in 25-50% of patients infected in childhood.</p> Signup and view all the answers

<p>Most patients with Acute Flaccid Myelitis (AFM) had a mild respiratory illness or fever prior to the onset of AFM.</p> Signup and view all the answers

<p>Meningitis is the inflammation of the meninges, while encephalitis is the inflammation of the brain itself.</p> Signup and view all the answers

<p>Meningoencephalitis is the infection with inflammation of both the meninges and the brain, often occurring as a complication of viral infections.</p> Signup and view all the answers

<p>Enteroviruses, particularly EV-D68, are associated with respiratory illnesses that can precede cases of AFM.</p> Signup and view all the answers

<p>The main viral agents are enteroviruses, herpes simplex virus (HSV), rabies virus, and arboviruses.</p> Signup and view all the answers

<p>Both poliovirus infections and AFM predominantly affect children, with AFM being more common in those under 18.</p> Signup and view all the answers

<p>Expected clinical features include headache, fever, confusion, and drowsiness, which may progress to convulsions and coma if severe.</p> Signup and view all the answers

<p>The virus is transmitted naturally between aquatic birds by Culex mosquitoes, then overflows into pigs and humans, who are dead-end hosts.</p> Signup and view all the answers

<p>JEV likely enters the CNS from the blood, facilitated by peripheral replication and viraemia, with a possible 'Trojan horse' mechanism via infected leukocytes.</p> Signup and view all the answers

<p>Common signs include headache, high fever, stiff neck, stupor, and may progress to paralysis, seizures, and coma.</p> Signup and view all the answers

<p>45-70% of survivors may experience neuropsychiatric sequelae.</p> Signup and view all the answers

<p>Neutralizing antibodies are sufficient to prevent encephalitis by blocking the virus's entry into the CNS.</p> Signup and view all the answers

<p>In utero infection can lead to abortion of the fetus.</p> Signup and view all the answers

<p>Complications can include flexion deformities and marked weakness or wasting.</p> Signup and view all the answers

<p>About 1 in 25 to 1 in 1,000 infected individuals develop symptomatic disease.</p> Signup and view all the answers

<p>About 30% of hospitalized patients with JE die.</p> Signup and view all the answers

<p>Survivors often experience severe neurologic sequelae, including learning difficulties and behavioral problems.</p> Signup and view all the answers

<p>About 30% of herpes simplex encephalitis cases result from initial HSV infection.</p> Signup and view all the answers

<p>The most common presentation of VZV in children is chickenpox (varicella).</p> Signup and view all the answers

<p>Rabies virus spreads via retrograde flow in axons, moving along peripheral nerves to the CNS.</p> Signup and view all the answers

<p>Negri bodies are the classic histopathologic feature of rabies.</p> Signup and view all the answers

<p>Post-exposure protection includes recombinant antigen vaccine, human anti-sera, or monoclonal antibodies.</p> Signup and view all the answers

<p>The three phases are prodromal (fever, nausea), furious (agitation, seizures), and dumb (paralysis, stupor).</p> Signup and view all the answers

<p>The primary neurological complications include AIDS Dementia Complex, Vacuolar Myelopathy, Peripheral Neuropathy, and Meningitis.</p> Signup and view all the answers

<p>HIV-1 easily crosses the blood-brain barrier, allowing it to infect neuronal cells early in the infection process.</p> Signup and view all the answers

<p>They release neurotoxic viral proteins that activate astrocytes, resulting in elevated glutamate levels and subsequent neuronal injury.</p> Signup and view all the answers

<p>CNS compartmentalization refers to instances where HIV-1 variants found in the cerebrospinal fluid (CSF) are not present in the peripheral blood, indicating a separate viral reservoir.</p> Signup and view all the answers

<p>Sustained viral replication and high viral load cause brain tissue inflammation, permanent cell death, and contribute to HIV-associated neurocognitive disorders.</p> Signup and view all the answers