Neuroinfections including meningitis and encephalitis

What Are Neuroinfections?

Neurological infections, also known as neuroinfections, occur when pathogens such as bacteria, viruses, parasites, fungi or prion invade the nervous system through the bloodstream or peripheral nerves. 

One of the most common neuroinfections includes meningitis, an inflammation of the meninges, which are three membranes that cover the brain and the spinal cord. Another example is encephalitis, an inflammation of the brain itself. Neuroinfections may result in significant long-term cognitive disabilities such as memory loss, physical disabilities such as blindness, speech or hearing loss, permanent nerve damage, or even death due to severe inflammation in the brain. Thus it is essential to seek urgent medical attention if you suspect that you may have a neuroinfection.

What does having a neuronfection feel like?

Although redness, swelling, pain and fever are characteristic of most neuroinfections, neuroinfections rarely present with classic signs and may mimic the symptoms of other diseases, such as influenza. You may also experience different symptoms depending on the type of neuroinfection you have.


Symptoms of viral and bacterial meningitis may be similar on first presentation. However, if you have bacterial meningitis, your symptoms will typically develop and worsen more rapidly. 

Symptoms of meningitis may include: 

  • High fever 
  • Pain (headaches, muscle and joint pain) 
  • Seizures
  • Dizziness
  • Sensitivity to bright light 
  • Vomiting and nausea 
  • Rashes/ purple areas on skin that resemble bruises 
  • Chills 


Viral encephalitis is most common. Symptoms of encephalitis may be similar to that of meningitis, and can range from mild to severe. 

Symptoms of encephalitis may include: 

  • High fever 
  • Pain (headaches, muscle and joint pain) 
  • Seizures
  • Comas 
  • Sensitivity to bright light 
  • Dizziness
  • Vomiting and nausea 
  • Hallucinations 
  • lethargy / drowsiness

What are the causes and risk factors of neuroinfections?

Most neuroinfections are caused by viral and bacterial infections. Neuroinfections can be categorized into two groups – acute and chronic. Acute neuroinfections develop within one to seven days, while chronic neuroinfections develop over the course of a few weeks. For example, acute meningitis may arise due to the herpes simplex virus within three to seven days, while chronic meningitis may arise due to tuberculosis over the course of two weeks or more. 

Viral neuroinfections may be contracted due to direct contact with the saliva, nasal mucus, or faeces of an individual who already has a neuroinfection. 

However, it is worthy to note that though uncommon, neuroinfections may occur due to non-infectious etiologies as well. Some known non-infectious causes of neuroinfections include: 

  • Cancers 
  • Autoimmune diseases such as lupus 
  • Injury to the brain/ head 
  • Certain medications/ drugs

How are neuroinfections diagsed?

Neuroinfections are life-threatening if not treated early. Thus, early diagnosis is key. If you are currently experiencing the symptoms listed above, consult a doctor and seek medical treatment immediately. 

To determine the severity and cause of your neuroinfection, your doctor may conduct one or more of the following: 

Detailed physical and neurological examination. Your doctor will have to conduct a thorough medical examination before definitively diagnosing your neuroinfection. Your doctor may also ask you about your medical history and perform tests to evaluate your vision, speech and reflexes. 

CSF (cerebrospinal fluid) analysis. For a CSF analysis, your cerebrospinal fluid will be collected by your doctor through a procedure called a spinal tap, also known as a Lumbar Puncture (LP).

Neuroimaging (CT, MRI scans). Your doctor may make use of neuroimaging to diagnose your neuroinfection. Neuroimaging refers to the use of various techniques to image the structure, function, or pharmacology of the nervous system. Your doctor may use this to help visualise the nervous system and identify the site of inflammation. This would allow for rapid diagnosis and subsequent treatment decisions made by your doctor. 

EEG (Electroencephalography). EEG refers to a test used to evaluate the electrical activity in your brain. It is non-invasive and enables your doctor to identify abnormal brain waves by monitoring electrical activity in your brain through the skull. This will aid your doctor in diagnosing patterns that may suggest a specific type of viral infection.

How are neuroinfections treated?

We offer various diagnostic and treatment options for neuroinfections. Your doctor may perform a Lumbar Puncture (LP) to collect a sample of cerebrospinal fluid from the spinal cord for testing and diagnosis. 

Following a confirmed diagnosis, your doctor may then start you on broad-spectrum antibiotics and antivirals in order to treat your infection.

  1. Encephalitis | Cedars-Sinai. (2019).
  2. Meningitis: Symptoms, Causes, Types, Treatment, Risks, & More. (2018). Healthline. 
  3. NHS Choices. (2019). Symptoms –  Meningitis. NHS.