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Naegleria fowleri, more commonly known as the "brain-eating amoeba", is a shape-shifting species that causes a sudden severe infection in the brain called naegleriasis. It is a fatal infection in most cases. This species is typically found in bodies of warm freshwater, such as ponds, lakes, rivers, and hot springs. It is also found in the soil near warm-water discharges of industrial plants, and in unchlorinated or minimally-chlorinated swimming pools. 

This brain-eating bug spreads in summers as it thrives in warm water. As the water temperature rises, its numbers increase. There is no evidence of this species living in salt water. 

This brain-eating infection is rare but is more common in the summer months. According to the Centers for Disease Control (CDC), only 34 cases  were reported in the United States between the years 2008 and 2017. In Pakistan however, there have been several cases this year alone. 

What is naegleriasis?

Also known as primary amoebic meningoencephalitis, it is an infection of brain. Signs and symptoms appear up to 9 days after exposure to the micro-organism. Initial symptoms include change in taste and smell and headache. 

If you have recently been to a pool, or on a picnic at a lake and start feeling ill a couple of days later, do not wait and see your doctor immediately. 

How does it get to the brain?

N. fowleri eventually gets to the brain through the nose. It travels in the mucosal lining of the nasal passage and invades the nasal tissues. Contaminated water enters the nose during activities like swimming, bathing or nasal irrigation. The bug travels along the olfactory nerves (responsible for smell) deeper into the skull and then into the brain. There it feeds on brain tissue until tissue begins to die and bleeding starts. 

Once the brain infection begins the immune system sends an army of soldier cells to the site of infection that tries to wall off the infection. This results in the inflammation of the brain and swelling. However, since the brain is warm and moist just like other fresh water bodies, it is an ideal environment for the amoeba. The brain continues to swell and because this infection is contained within the skull there is no space for the infection to spread. The rising pressure inside the skull causes the brain to disconnect from the spinal cord hence the rest of the body as well. 

What are the signs and symptoms?

Most people wouldn’t go the doctor’s with a headache. However, if there is a recent history of going to the pool, lake or nasal irrigation from a public water supply such as a public washroom then please see your doctor just to make sure. If you feel like your food doesn’t taste the way it usually does, or notice that your sense of smell has altered, mention these changes to your doctor as well. 

Other signs and symptoms to look out for are:

  • Nausea
  • Vomiting
  • Backpain
  • Stiff neck

These are non-specific symptoms that are likely to show up a few days after contact with the amoeba. Since N. Fowleri causes a type of meningitis, more severe infection would cause more serious symptoms like:

  • Hallucinations
  • Confusion
  • Lack of attention
  • Lack of coordination
  • Cramps 
  • Seizures

If you think you have been experiencing any of the above symptoms please don’t wait to see your doctor. If you can’t get to one right away then find an online doctor in Pakistan through an online doctor mobile app. You can get an expert medical opinion sitting at home. If the doctor sees it as urgent then visit the nearest medical facility. 

Once the symptoms begin, the disease progresses rapidly over the next few days with death occurring within 7-14 days. Remember that there is no age group for this disease. Most commonly it is seen to affect children and young adults who with recent exposure to clean bodies of water. 

Microscopic view

Under a microscope they are seen to exist in 3 stages; a cyst, a trophozoite and a flagellate. In human tissue it exists as a trophozoite so it can multiply in great numbers and in the spinal fluid as a flagellate. It eats the brain tissue by releasing deadly digestive enzymes that breaks it into pieces. 

How is the infection diagnosed?

If you have been to lake, stream, swimming pool or might have inhaled water from other fresh water sources through nasal irrigation and aren’t feeling well, make an appointment to see your healthcare provider right away. Be sure to let them know if you’ve been in any freshwater recently.

Depending on your history and symptoms, a sample of cerebrospinal fluid (CSF) may be collected for testing. CSF is the fluid that surrounds and protects your brain and spinal cord. It’s collected through a process called a lumbar puncture. This is done by inserting a needle between two of the vertebrae (backbones) in your lower back.

A CSF sample can provide information on CSF pressure as well as levels of blood cells and proteins, which are abnormal in people with PAM. The actual Naegleria amoeba may also be visible under the microscope in a CSF sample.

If the doctor feels it is necessary, you may also need to have an MRI or CT scan done on your head.

If you want to get your lab reports checked or a radiology scan like an MRI/CT interpreted then find an online radiologist at My live doctors and understand what the report means. Download the app on your smartphone or mobile device, sign up for free and book an online doctor appointment in Pakistan. 

Ask a doctor in Lahore or any city across Pakistan and receive expert medical advice from the comfort of your own home. You don’t need to travel long distances for a second opinion anymore. With Online health services like My live doctors you can access qualified healthcare professionals anytime, anywhere. 

How do you treat the infection?

Effective treatment methods are still being studied and explored since it is a rare infection. However, the antifungal medication amphotericin B can be given intravenously or injected into the area around your spinal cord. Another new drug called miltefosine seems to be useful for treating Naegleria infections. Other anti-fungals and anti-biotics may also be used for symptom relief. 

The key is prevention of the infection. Here are some tips:

  • Avoid swimming in streams and lakes, especially during warm weather
  • Use nose-clamps while swimming to prevent the water from entering your nose
  • Swim in pools that are chlorinated and have been properly disinfected

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