Occurrence and genetic characterisation of Acanthamoeba spp. from environmental and domestic water sources in Queen Elizabeth Protected Area, Uganda

Abstract

BackgroundAcanthamoeba is an emerging potentially pathogenic amoeba that has been receiving increasing attention worldwide as a reservoir and potential vector for the transmission of pathogenic bacteria. It is also associated with brain cell damage, keratitis and skin irritation in humans. Its effects are more severe in immunocompromised individuals. This study provides for the first time in Uganda, information on the prevalence and genotypes of Acanthamoeba in environmental and domestic (tap) water.MethodsA total of 324 environmental and 84 tap water samples were collected between November 2013 and September 2014. The samples were centrifuged, cultured (Non-Nutrient agar seeded with gram-negative bacteria) and observed under a microscope. After confirmation of Acanthamoeba, genomic DNA was extracted for PCR assays by chemical lysis and purification with phenol/chloroform/isoamyl alcohol. Samples that showed the strongest positive bands (400–600 bp) were subjected to cycle sequencing.ResultsAmong environmental and tap water samples, 107 (33 %) and 36 (42.9 %) tested positive for Acanthamoeba spp., respectively. Prevalence of Acanthamoeba from specific environmental locations was as follows; Kazinga channel banks (60.7 %), Fish landing sites (50 %), River Kyambura (39.6 %) and Kazinga mid channel (5.3 %). There was a significant difference (p = 0.001) in the prevalence of Acanthamoeba between sampling sites. The mean (Mean ± SE) occurrence of the organism was higher in Kazinga channel banks (3.44 ± 0.49) and Fish landing sites (3.08 ± 0.53). Correlation between in situ parameters and Acanthamoeba was insignificant except for the Dissolved Oxygen (mg/ML) which was negatively correlated (r = −0.231, p = 0.001) to Acanthamoeba. Six distinct partial Acanthamoeba T-genotype groups T1, T2, T4, T5, T6 and T11 were obtained. Ultimately, Acanthamoeba spp., Acanthamoeba hatchetti and Acanthamoeba polyphaga were isolated in the current study.ConclusionsThere was a high prevalence of Acanthamoeba in communal piped tap and environmental water used by communities, indicating poor environmental and domestic water quality.

Isolation of Acanthamoeba T5 from Water: Characterization of Its Pathogenic Potential, Including the Production of Extracellular Vesicles

“…In another study about the distribution of Acanthamoeba genotypes in water samples from mineral water bottles in Porto Alegre, southern Brazil, the authors reported genotype T5 as the most common among the sequences analyzed [60]. Finally, Sente et al (2016) [61] reported the isolation of Acanthamoeba in 36 domestic water sources (42.9%) in the Queen Elizabeth Protected Area, Uganda, including the genotypes T1, T2, T4, T5, T6 and T11. Even when Acanthamoeba genotype T5 is the second most frequent genotype isolated from environmental sources [1], there are few reports which correlate this genotype with a clinical case.…”

Determination of Bacterial Quality of Water in Randomly Selected Swimming Pools in Kampala City, Uganda

“…The microbial safety of swimming pool water is highly questionable in countries with poor regulatory framework due to the many existing possible microbial contaminant pathways. Microbial contamination of swimming pools can occur through (a) faecal contaminated source water or direct defecation from swimmers, birds, and animals [4][5][6][7], (b) nonfaecal human shedding from vomiting, sneezing, mucous, spitting, or skin, (c) poor wastewater disposal [8], (d) microbial biofilm formation along piped water networks [9,10], (e) contaminated air, dust, soil, or rainwater [11,12], and (f) individuals with contagious diseases or infectious pathogens [4,8].…”

“…Unless the pool is cleaned and maintained and its water adequately treated, contamination may lead to a number of disease outbreaks such as gastroenteritis, conjunctivitis, keratitis, trachoma, otitis, cholera, dysentery, eczema, skin rashes, typhoid, dysentery, giardiasis, cryptosporidiosis, helminthiasis, cholera, hepatitis, rotavirus infection, salmonellosis, and central nervous systems associated diseases [3,[13][14][15][16][17][18][19][20][21][22][23]. The aetiologic agents of some of these diseases have been isolated from natural and domestic water sources in Uganda and are associated with devastating illnesses [9,10,24,25]. Not much has been studied about microbial contamination of swimming pool water in Uganda, but available data denotes the presence of Streptococcus and Escherichia coli [26,27].…”

“…It has also been reported that the surviving disinfectant tolerant pathogens might also be antibioticresistant, a fact already documented for bacterial isolates from treated drinking water [4] and purified sewage effluents [35]. It is important to continuously test swimming pool water for the availability of pathogens that pose public health risks to humans in order to optimise water treatment methods to get the best performing chemicals that can kill or reduce these pathogens to minimal or nonworrying levels [9,10,24]. In Uganda, there is scanty information on the general hygiene of swimming pools.…”

Xenic Cultivation and Genotyping of Pathogenic Free-Living Amoeba from Public Water Supply Sources in Uganda

“…Free-living amoeba (FLA) of the genera Naegleria, Acanthamoeba, and Hartmannella have been associated with water-related illnesses, especially in developed countries found in America, Europe, and the Middle East [1][2][3][4]. In many parts of Uganda, there is dependence on environmental water for washing, recreation, drinking, cooking, and other domestic purposes [5]. However, in most cases, this water is used without treatment, an act which predisposes Ugandans to FLA infection [5].…”