Diseases Due To Free-Living Amebas

Authors

  • Sebastian Leonardo Godoy Universidad Abierta Interamericana, Facultad de Medicina y Ciencias de la Salud, Carrera de Medicina. Buenos Aires, Argentina. Author
  • Gerardo Laube Universidad Abierta Interamericana, Facultad de Medicina y Ciencias de la Salud, Carrera de Medicina. Buenos Aires, Argentina. Author

DOI:

https://doi.org/10.56294/shp2025205

Keywords:

Acanthamoeba spp, Balamuthia mandrillaris, Pathogenesis of amoebic meningoencephalitis

Abstract

Introduction: Acanthamoeba spp., Balamuthia mandrillaris and Naegleria fowleri are pathogenic free-living amoebae (FLA) and are commonly found in the environment, particularly in soil. This pathogenic FLA causes granulomatous amoebic encephalitis (GAE) or primary amoebic meningoencephalitis (PAM) that affects the central nervous system and can also cause keratitis and skin infections. Objectives: In the present study, our objective was to determine the quantitative concentration of Acanthamoeba spp., B. mandrillaris and N. fowleri in soil samples collected from places where human contact is high by means of an assay and to reach the conclusion of contagion in these. Materials and methods: A systematic review was performed in the following databases: PubMed; EMBASE; Cochrane; BVS, Cinahl and Web of Science. After the initial steps, the most relevant data were extracted from each article and compiled in full text in topics according to the chosen outcome.
Results: The qPCR assay detected a total of 45.71 % (n = 16) of Acanthamoeba spp., 20 % (n = 7) of B. mandrillaris and 17.4 % (n = 6) of N. fowleri in five different soil sources. The quantitative concentration of Acanthamoeba spp., B. mandrillaris,5 - 6 × 10 2 , 47 × 10 4 to 39 × 10 3 , and 9 × 10 3 - 8 × 10 2 plasmid copies/gr, respectively. While the highest quantitative concentration of Acanthamoeba spp. and B. mandrillaris was determined in garden soil samples, N. fowleri was detected in potting soil samples. Three different genotypes T2 (18.75 %), T4 (56.25 %) and T5 (25 %) were identified from Acanthamoeba positive soil samples. The T4 genotype of Acanthamoeba was the most frequently detected genotype in soil samples and is also the most common genotype causing infection in humans and animals. To our knowledge, the present study is the first to identify the T5 genotype in soil samples from Turkey. 
Conclusion: people and especially children should be aware of the hidden danger in the garden and potting soil samples they come into contact with most frequently. Public health awareness of human infections that may arise due to contact with soil should be increased. Public health specialists should raise awareness of this hidden danger in soil.

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Published

2025-05-15

How to Cite

1.
Leonardo Godoy S, Laube G. Diseases Due To Free-Living Amebas. South Health and Policy [Internet]. 2025 May 15 [cited 2025 Aug. 19];4:205. Available from: https://shp.ageditor.ar/index.php/shp/article/view/205