Brain-eating amoeba • What it is and how to avoid it

Following the appearance of the last two cases in Israel, it is useful to know what the amoeba is and how it can be avoided. By: Dr. Hana Farah, specialist in infectious diseases in children, Child Health Center, Nahariya, Klalit Health Services.

What is an amoeba?

This is a group of single-celled creatures, characterized by mobility about the arms and the tail
to those that are in our environment such as, in the soil and water. The amoeba that recently caused the disease in both cases in Israel this year, is known as Naeglera fowleri (or as it is popularly known by the dreaded brain-eating amoeba) that lives in fresh and warm water such as lakes, puddles and hot springs.

How do you get infected with amoeba?

The infection with Bengalaria is by infiltration/inhalation of contaminated water through the nostrils that occurs while diving in contaminated water reservoirs or by contaminated water that is splashed directly into the nasal mucosa. From there it penetrates through the olfactory nerve directly into the brain and is fed by the brain cells. It is important to note that it is not possible to get infected by drinking water and it does not pass from one person to another.

Is there a danger in pool water or salt water?

No. Hangaria does not survive in salty water like the sea or water with chlorine like in public swimming pools. In addition, it should be noted that in fresh water the chance of contracting the disease after exposure is rare.

What are the main symptoms of infection and when do they appear?

The symptoms usually appear about 3-7 days after the exposure but can appear up to 14 days after the exposure. The main symptoms are usually as a result of the inflammation in the membrane and brain tissue and include: high fever, severe headache, stiff neck, nausea and vomiting. Neurological deterioration is also possible within a few days, causing cognitive impairment, disorientation, extreme restlessness and even convulsions, loss of consciousness and usually death within 5-10 days.

How is the diagnosis made?

If there are typical symptoms and suspected exposure to contaminated water, a lumbar puncture should be performed, which usually shows a typical picture of encephalitis. The laboratory diagnosis is made by sending a PCR sample from the spinal cord fluid. Also, it is sometimes possible to identify the Nagelaria directly on the surface due to a characteristic appearance with a snail-like movement.

How are patients treated?

There is no specific treatment for the disease, but it can be treated with the help of a medicinal combination that includes antibiotics against fungi, parasites and bacteria administered intravenously, in combination with direct treatment into the spinal cord fluid. Other treatments include steroid treatment, cooling and reducing intracranial pressure. It is important to note that despite the treatment, the disease is deadly and extremely violent with a high mortality rate.

How can the disease be avoided?

Amoeba infection can be avoided by avoiding swimming in suspicious places, and by chlorinating the water. Since the infection occurs through penetration of the nasal mucosa, it is recommended to avoid immersing the head in suspicious water in order to significantly reduce the direct entry of the amoeba from the nasal mucus into the brain.