Occurrence of Free-Living Amoebae in Communities of Low and High Endemicity for Buruli Ulcer in Southern Benin

Abstract

Buruli ulcer or Mycobacterium ulcerans disease occurs mainly in areas in proximity to standing or slowly running freshwater, habitats in which free-living amoebae occur. For this reason, a possible link between the habitat of M. ulcerans and free-living amoebae was investigated. Free-living amoebae and mycobacteria were isolated from water and biofilm specimens taken from protected and unprotected sources of water in villages known to have either high or low endemicity for Buruli ulcer in Benin. Amoebae were isolated from 78.8% of samples. A greater proportion of water bodies in areas of high endemicity had amoebae than in areas of low endemicity (83.3% versus 66.7%). Protected sources of water were significantly more likely to contain amoebae in areas of high endemicity than in areas of low endemicity (88.0% versus 11.1%). Several pathogenic free-living amoebae and mycobacteria were isolated. However, no M. ulcerans was isolated and no specimen was positive for IS2404 PCR. Our results show that the study area has a water hygiene problem, which is greater in areas of high Buruli ulcer endemicity than in areas of low endemicity. Our observations indicate that additional studies are required to explore the possible link between free-living amoebae and mycobacteria.

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). Acanthamoeba and Naegleria species have been isolated from the Queen Elizabeth Park in the same area of western Uganda, where the first outbreak of Bundibugyo EBOV occurred in western Uganda.…”

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

“…Previous environmental studies in different countries in Africa have reported the presence of potentially pathogenic Acanthamoeba strains mainly in water sources. [6][7][8][9] Furthermore, only three clinical related studies regarding Acanthamoeba genus have been reported in Africa: one case of encephalitis due to Acanthamoeba in Dakar, Senegal, 14 an epidemiological study to determine the presence of FLA in the nasal passages of a population in Zaria, Nigeria 24 and the report of three cases of AK in patients from Tunisia. 16 Another case of encephalitis due to a hartmannellid amoeba was reported in Zambia; 25 however, it is possible that the identification of this strain was not carried out correctly.…”

“…Nevertheless, studies on the presence of potentially pathogenic genotypes of Acanthamoeba, as well as Naegleria fowleri, in environmental sources has been reported by other authors in this continent (including countries such as Nigeria, Tunisia, Benin, and Egypt among others). [5][6][7][8][9] Moreover, only a few clinical cases of amoebic encephalitis have been reported in Nigeria (N. fowleri), [10][11][12] South Africa (N. fowleri), 13 and Senegal (Acanthamoeba).…”

Epidemiology and disease burden of Buruli ulcer: a review

“…Rather than free-living, it may persist in the environment as a commensal, associated with other protective organisms such as amoebae. [28][29][30] However, detection of M. ulcerans-specific DNA sequences in many biotic components of aquatic ecosystems, such as plants, snails, fish, or insects, has been also interpreted as indication for the ubiquitous presence of this pathogen in these habitats. Furthermore, mycolactone-producing mycobacteria have been isolated from different fish and frog species presenting with mycobacterial infections.…”