Overview of Encephalitis and its Relationship to STDs

Human head and brain
Human head. Coloured composite image of a magnetic resonance imaging (MRI) scan of the brain and 2D and 3D computed tomography (CT) scans of the head and neck of a 35 year old patient.. Zephyr/Science Photo LIbrary/Getty Imges

What is Encephalitis?

Encephalitis is an infection of the brain tissue. It is usually caused by a virus. Some types of viruses that can cause encephalitis include arboviruses, enteroviruses, and herpes viruses. However, most viral infections do not lead to encephalitis. It is a rare complication of infection.

Symptoms of encephalitis are highly variable and include:

  • headaches
  • fever
  • memory problems
  • personality changes
  • other problems less obviously linked to the brain, such as nausea.

Common Misspellings: encephelitis

What is the Relationship Between STDs and Encephalitis?

Encephalitis can be a consequence of either neonatal or adult herpes infection. In fact, some scientists think that herpes encephalitis may be a risk factor for Alzheimer's disease. Encephalitis can be caused by either HSV-1 or HSV-2.

Herpes encephalitis is one of the reasons that neonatal herpes can be fatal. It can also be fatal in adult patients. A significant fraction of herpes encephalitis patients die even when they receive antiviral medication in a timely manner. The risk of death or severe brain damage is even higher in individuals who do not receive prompt treatment. Herpes encephalitis may be more common in people who are immunocompromised.

Untreated HIV infection is also associated with an increased risk of neurocognitive problems.

This includes encephalitis. However, much of the brain damage caused by HIV is due to relatively low-level swelling. It is not necessarily a result of direct infection of the brain. HIV infection of the CNS can occur, but it's not the only reason HIV causes such problems.


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Lescure FX, Moulignier A, Savatovsky J, Amiel C, Carcelain G, Molina JM, Gallien S, Pacanovski J, Pialoux G, Adle-Biassette H, Gray F. CD8 encephalitis in HIV-infected patients receiving cART: a treatable entity. Clin Infect Dis. 2013 Jul;57(1):101-8. doi: 10.1093/cid/cit175.

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