Title: Naegleria fowleri: Unveiling the Deadly Amoeba Introduction: This document provides a concise overview of Naegleria fowleri, a highly pathogenic amoeba that can cause a rare but fatal brain infection called primary amebic meningoencephalitis (PAM). It explores the key aspects of Naegleria fowleri, including its characteristics, life cycle, transmission, symptoms, diagnosis, and preventive measures. Characteristics: Naegleria fowleri is a free-living amoeba commonly found in warm freshwater environments, such as lakes, hot springs, and poorly maintained swimming pools. It thrives in temperatures between 25°C and 45°C (77°F and 113°F). As a single-celled organism, Naegleria fowleri possesses a distinct amoeboid shape and exhibits rapid motility. Life Cycle: The life cycle of Naegleria fowleri involves several stages. In its active form, known as the trophozoite, it feeds on bacteria and other organic matter present in the water. Under adverse conditions, such as the absence of nutrients or when exposed to unfavorable temperatures, the trophozoite transforms into a dormant cyst, allowing it to survive in harsh environments. Transmission: Naegleria fowleri primarily infects humans through the nasal passage. It can enter the body when contaminated water enters the nasal cavity, typically during activities like swimming, diving, or using inadequately disinfected water for nasal irrigation. It is important to note that Naegleria fowleri infection does not occur through drinking contaminated water or by coming into contact with an infected person. Symptoms and Diagnosis: The symptoms of Naegleria fowleri infection often resemble those of bacterial meningitis and typically manifest within a few days of exposure. Initial symptoms may include severe headache, fever, nausea, and vomiting, which rapidly progress to stiff neck, seizures, altered mental status, and coma. Diagnosis is challenging due to the rarity of the infection and the rapid progression of symptoms. However, specialized laboratory tests, such as polymerase chain reaction (PCR), can detect the presence of Naegleria fowleri DNA in cerebrospinal fluid. Prevention: Preventive measures play a crucial role in avoiding Naegleria fowleri infection. These include avoiding activities that involve water entering the nasal passage in warm freshwater bodies where the amoeba is likely to be present. Proper maintenance and disinfection of swimming pools and hot tubs, as well as using sterile water for nasal irrigation, are essential precautions. Awareness about the infection and its associated risks is key to preventing Naegleria fowleri-related fatalities. Conclusion: Naegleria fowleri is a rare but dangerous amoeba that can cause a devastating brain infection. Understanding its characteristics, life cycle, transmission routes, symptoms, and diagnostic challenges is crucial for early identification and prompt treatment.

1. Naegleria fowleri
PRESENTED BY
ARJUN M
BSc MLT

2. INTRODUCTION
 Naegleria fowleri is a single-celled, free-living amoeba that
belongs to the phylum Percolozoa. It is commonly known as
the “brain-eating amoeba” due to its ability to cause a rare
but severe infection called primary amebic
meningoencephalitis (PAM). Naegleria fowleri is primarily
found in warm freshwater environments such as lakes, hot
springs, and poorly maintained swimming pools.

3. Naegleriafowleri exhibitsseveral
interestingcharacteristics:

4. Morphology
 Naegleria fowleri exists in three main morphological
forms: trophozoite, cyst, and flagellate. The trophozoite
form is the active, feeding stage, whereas the cyst form
is a dormant and resistant stage that allows the
amoeba to survive under adverse conditions.

6. Life cycle of naegleria fowleri

7. Feedingand
locomotion
 Naegleria fowleri is a heterotrophic organism
that feeds on bacteria and other small organisms
present in the environment. It moves by
extending pseudopods (false feet) and exhibits
amoeboid motion.

9. Pathogenicity
 Naegleria fowleri is capable of causing a severe
and often fatal infection in humans. The amoeba
enters the body through the nose when
contaminated water is inhaled during activities
such as swimming, diving, or using a
contaminated neti pot. From the nasal passages,
it migrates to the brain, leading to the
destruction of brain tissue and inflammation.

10. Optimal
conditions
 Naegleria fowleri thrives in warm freshwater
environments with temperatures between 25 to
46 degrees Celsius (77 to 115 degrees
Fahrenheit). It can survive in both natural bodies
of water and man-made water systems, such as
poorly maintained hot tubs and swimming pools.

11. Diagnosis
 Microbiological diagnosis of Naegleria fowleri
infection involves obtaining a cerebrospinal fluid
(CSF) sample and examining it under a
microscope for the presence of the amoeba. The
trophozoite form of the organism is typically
observed.

12. Treatmentand
prevention
 PAM caused by Naegleria fowleri is difficult to
treat, and the infection is often fatal. Antifungal
and antimicrobial drugs, such as amphotericin B,
are commonly used, but their effectiveness is
limited. Prevention measures include avoiding
warm freshwater bodies where the amoeba may
be present and taking precautions to prevent
water from entering the nose, such as using nose
clips or keeping the head above water.
 Overall, Naegleria fowleri is a fascinating and
potentially dangerous microorganism that
highlights the importance of water safety and
proper hygiene practices, particularly in warm
freshwater environments.

13. THANK YOU