Presence of potentially pathogenic free-living amoebae strains from well water samples in Guinea-Bissau

Abstract

Free-living amoebae (FLA) include opportunistic pathogens such as Naegleria fowleri, Balamuthia mandrillaris, and the genera Sappinia and Acanthamoeba. In this study, a survey was conducted in order to evaluate the presence of potentially pathogenic amoebic strains in water samples collected from wells located in the western part of Guinea-Bissau. The samples were left to precipitate for 48 hours and then the sediments were seeded on non-nutrient agar plates containing Escherichia coli spread and cultures were checked daily for the presence of FLA. Identification of FLA strains was based on the morphological and polymerase chain reaction (PCR) using the 18S rDNA or 16S mitochondrial rDNA genes in the case of Naegleria and Balamuthia genera, respectively. In the case of positive samples of Acanthamoeba, strains were further classified at the genotype level by sequencing the diagnostic fragment 3 (DF3) region located in the 18S rDNA gene as previously described. Sappinia sp. was not isolated during the study and thus, no molecular analysis was performed for this genus. The obtained results revealed the presence of Acanthamoeba (genotypes T3 and T4), Naegleria fowleri, and Balamuthia mandrillaris. To the best of our knowledge, this is the first report demonstrating the presence of FLA in water bodies from GuineaBissau and the first report on the isolation of Balamuthia mandrillaris from environmental sources in Africa.

A case report: primary amoebic meningoencephalitis in a young Zambian adult

“…Following this case, another PAM patient was reported 2 years later in the same country [ 20 ]. In addition, there is documentation of N. fowleri isolation from environmental sources [ 21 – 23 ]. N. fowleri has also been isolated from nasal passages during the dry, windy and dusty months (hamarrtan season) affecting parts of the West African coast [ 23 ].…”

Functional Assessment of 2,177 U.S. and International Drugs Identifies the Quinoline Nitroxoline as a Potent Amoebicidal Agent against the Pathogen Balamuthia mandrillaris

“…While systematic ecological studies of B. mandrillaris have not been performed, free-living B. mandrillaris amoebae have been isolated from water, soil, and dust across all continents ( 10 – 18 ). Cases of human and animal infections are also reported on all continents but are most common in South America and the southern United States ( 19 – 35 ) (reviewed in references 31 , 32 , and 33 ).…”

Indentifying and modeling the distribution of cryptic reservoirs of Ebola virus using artificial intelligence

“…Acanthamoeba, N. fowleri, and B. mandrillaris have been isolated from water bodies from Guinea-Bissau, and this is the first report of the isolation of B.mandrillaris from environmental sources in Africa (52). Naegleria and Acanthamoeba species have also been isolated from Benin (53).…”