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1.
Acta Parasitol ; 65(1): 174-186, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31797194

RESUMO

PURPOSE: The main goal of this study was genotyping of free-living parasites and sub-grouping of pathogenic or non-pathogenic amebae obtained from Turkey's thermal springs. In so doing, distribution and abundance of possible pathogenic or causative strain for humans, which are caused by Acanthamoeba and Naegleria strains, would be elaborated. The number of extensive studies on the general occurrence and distribution of parasitic strains is very high worldwide, but there has been a paucity of information with regard to Turkey. METHODS: From a total of 434 obtained thermal pool samples, free-living amebas were isolated from 148 water samples using the non-nutrient agar (NNA) culture method. Subsequently, the cultivated samples were used for DNA isolation; then 102 obtained DNA samples were subjected to PCR amplification using various primers for samples of genera Acanthamoeba and Naegleria. Ultimately, estimation of genotype or subtype was evaluated by sequencing. RESULTS: About 29 samples that belong to Acanthamoeba and Naegleria were estimated from a total of 102 amplified PCR samples. These eukaryotic PCR products which have Acanthamoeba genus appearance, generated 26 subtypes and 3 Naegleria samples. Among the 26 Acanthamoeba genotypes, 22 aligned sequences were matched with various GenBank reference samples, while the 4 divergent genotypes were not elaborated and marked as ND. Most of the Acanthamoeba genera were determined as likely dominating groups and clustered as T form within totally eight groups. Eight, seven and three subtypes were found as T4A, T15 and T11 genotypes, respectively while the remainings were ultimately found in four groups. Results confirming the predominance of T4A, which is known the most causative form, the presence in the pools. Despite being uncommon, N. fowleri, lovaniensis and australiensis were also observed among the surveyed pools. CONCLUSION: The present study is descriptive and is not unique. However, this is the most comprehensive study of the molecular distribution sampling of thermophilic Acanthamoeba and Naegleria that confirmed and demonstrated their ubiquitous presence throughout Turkey. By this estimation, in some spas, the most and likely causative form Acanthamoeba including T4 and Naegleria fowleri has also been confirmed.


Assuntos
Acanthamoeba/genética , Técnicas de Genotipagem , Fontes Termais/parasitologia , Naegleria/genética , Acanthamoeba/classificação , DNA de Protozoário/genética , Genótipo , Geografia , Naegleria/classificação , Análise de Sequência de DNA , Turquia
2.
J Water Health ; 17(5): 813-825, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31638031

RESUMO

This study aimed to identify the Acanthamoeba genotypes and their pathogenic potential in five recreational hot springs in Peninsular Malaysia. Fifty water samples were collected between April and September 2018. Physical parameters of water quality were measured in situ while chemical and microbiological analyses were performed in the laboratory. All samples were filtered through the nitrocellulose membrane and tested for Acanthamoeba using both cultivation and polymerase chain reaction (PCR) by targeting the 18S ribosomal RNA gene. The pathogenic potential of all positive isolates was identified using thermo- and osmotolerance tests. Thirty-eight (76.0%) samples were positive for Acanthamoeba. Water temperature (P = 0.035), chemical oxygen demand (P = 0.026), sulphate (P = 0.002) and Escherichia coli (P < 0.001) were found to be significantly correlated with the presence of Acanthamoeba. Phylogenetic analysis revealed that 24 samples belonged to genotype T4, nine (T15), two (T3) and one from each genotype T5, T11 and T17. Thermo- and osmotolerance tests showed that 6 (15.79%) of the Acanthamoeba strains were highly pathogenic. The existence of Acanthamoeba in recreational hot springs should be considered as a health threat among the public especially for high-risk people. Periodic surveillance of hot spring waters and posting warning signs by health authorities is recommended to prevent disease related to pathogenic Acanthamoeba.


Assuntos
Acanthamoeba/crescimento & desenvolvimento , Fontes Termais/parasitologia , Acanthamoeba/isolamento & purificação , Genótipo , Malásia , Filogenia , RNA Ribossômico 18S
4.
Artigo em Inglês | MEDLINE | ID: mdl-30513967

RESUMO

A growing number of people undertake international travel, and yet faster growth of such travel is expected in the tropics. Information on the hazards presented by pool and hot spring waters in tropical countries is very limited. This review aims to collate available information on pool water quality, alongside data on cases and outbreaks associated with swimming in pools in tropical regions affecting both local populations and travellers. Bacteria species commonly causing cases and outbreaks in the tropics as well as elsewhere in the world were excluded, and the review focuses on studies related to pathogens that, with the exception of Cryptosporidium, are unusual in more temperate climates. Studies concerning subtropical countries were included in the light of climate change. Diseases transmitted by vectors breeding in poorly maintained, neglected or abandoned pools were also included. 83 studies dealing with Microsporidia, Leptospira spp., Schistosomas spp., Cryptosporidium spp., Acanthamoeba spp., Naegleria spp., Clostridium trachomatis, viruses, and vectors breeding in swimming pool and hot tub waters, and fulfilling predefined criteria, have been included in our survey of the literature. In conclusion, prevention strategies for pool safety in the tropics are imperative. Public health authorities need to provide guidance to westerners travelling to exotic destinations on how to protect their health in swimming pools.


Assuntos
Doenças Transmissíveis/transmissão , Fontes Termais , Piscinas , Medicina de Viagem , Microbiologia da Água , Bactérias/isolamento & purificação , Eucariotos/isolamento & purificação , Fontes Termais/microbiologia , Fontes Termais/parasitologia , Fontes Termais/virologia , Humanos , Clima Tropical , Vírus/isolamento & purificação
5.
Exp Parasitol ; 195: 54-58, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30393165

RESUMO

Little is known about the prevalence of Balamuthia mandrillaris within the environment due to its difficult isolation, but once an axenic culture is established, it is relatively easy to maintain. As most of the time researchers are interested mainly in isolating B. mandrillaris from environmental samples, the flora that accompanies it becomes second in importance. Therefore, this study aimed to determine which potentially pathogenic free-living amoebae, in addition to B. mandrillaris, could be found co-inhabiting a source of natural thermal water called "Agua Caliente" (Mexico), where this amoeba has previously been detected twice by molecular methods. A third sampling from this same source was carried out to try to isolate B. mandrillaris and other free-living amoebae using 37 and 45 °C as isolation temperatures. For PCR techniques, specific primers were used for B. mandrillaris, Naegleria fowleri, and Acanthamoeba species, plus a universal primer set for the eukaryotic 18S SSU rRNA gene for other isolated amoebae. PCR products were sequenced for final identification. 42 strains of the primary isolate were obtained, but only 34 could be kept in culture. Of them, 23 strains were identified as Naegleria lovaniensis, eight strains as Acanthamoeba jacobsi, two strains as Stenamoeba sp. and only one was identified as Vermamoeba vermiformis. The isolation of B. mandrillaris was once again not successful, but the presence of potentially pathogenic and nonpathogenic free-living amoebae is reported for the first time in this type of water in Mexico thanks to molecular methodology.


Assuntos
Amoeba/patogenicidade , Fontes Termais/parasitologia , Acanthamoeba/classificação , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Acanthamoeba/patogenicidade , Amoeba/classificação , Amoeba/genética , Amoeba/isolamento & purificação , Balamuthia mandrillaris/classificação , Balamuthia mandrillaris/genética , Balamuthia mandrillaris/isolamento & purificação , Balamuthia mandrillaris/patogenicidade , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Genótipo , Fontes Termais/química , Concentração de Íons de Hidrogênio , México , Naegleria fowleri/classificação , Naegleria fowleri/genética , Naegleria fowleri/isolamento & purificação , Naegleria fowleri/patogenicidade , Filogenia , Reação em Cadeia da Polimerase , Espectrofotometria , Temperatura
6.
J Water Health ; 16(5): 807-813, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30285961

RESUMO

Acanthamoeba is a free-living protozoan that can be found in natural and artificial environments such as hot tubs, surface water and springs and can cause severe diseases including amoebic keratitis and granulomatous amoebic encephalitis. The present study was conducted owing to the lack of research regarding genotypes of Acanthamoeba in hot springs of Mazandaran province in northern Iran. Twenty-four water samples were collected from all hot springs in Mazandaran province. After filtration through nitrocellulose membrane, samples were cultured on non-nutrient agar medium enriched with TYIS-33. The cultures were microscopically examined for the presence of Acanthamoeba. Positive cultures were analysed by polymerase chain reaction (PCR) and genotypes were determined by targeting the 18 S rRNA gene. The pathogenic potential of all positive isolates was identified using thermotolerance and osmotolerance tests. Eleven (47.8%) samples were positive for Acanthamoeba. Based on sequencing analysis, 100% of isolates belonged to the T4 genotype. Thermo- and osmo-tolerance tests showed that four (36.3%) Acanthamoeba strains were highly pathogenic. According to our research, the occurrence of Acanthamoeba in recreational hot springs could be a hazard for high risk persons. Posting warning signs and regular monitoring of these waters by health planners may therefore be useful for decreasing Acanthamoeba spp. infections.


Assuntos
Acanthamoeba , Fontes Termais/parasitologia , Genótipo , Irã (Geográfico) , Reação em Cadeia da Polimerase
7.
Exp Parasitol ; 183: 240-244, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28916458

RESUMO

The present study tested 80 samples of municipal, geothermal and recreational water samples for the occurrence of waterborne free living amoebae (FLA) including Acanthamoeba, Balamuthia mandrillaris, Vahlkampfiids and Vermamoeba in Semnan province, North half of Iran. Four sets of primers including JDP1,2 primers, ITS1,2 primers (Vahlkampfiids), 16S rRNABal primers (Balamuthia mandrillaris) and NA1,2 primers (Vermamoeba) were used to confirm the morphological identification. From the 80 water samples tested in the present study, 16 (20%) were positive for the outgrowth of free living amoebae based on the morphological page key. Out of the 34 municipal water samples, 7 (20.6%) were positive for outgrowth of Free living amoeba, belonging to Vermamoeba, Naegleria and Acanthamoeba using molecular tools. Three out of the six investigated hot springs were also contaminated with Naegleria spp. Sequencing of the ITS1,2 region of the Vahlkampfiid isolates revealed the highest homology with N. gruberi (2 isolates), N. australiensis (1 isolate) and N. pagei (3 isolates). This is the first report of N. gruberi in the country. Using morphological and molecular analysis, Balamuthia mandrillaris was undetected in all the water samples. The present study further confirmed the occurrence of potentially pathogenic waterborne free living amoebae in habitats with high human activity. It is of utmost importance that more studies are conducted to evaluate the niches of B. mandrillaris and N. fowleri in Iran and worldwide. Such investigations regarding the relevance of FLA as a hazard to humans, should be brought to the notice of the health authorities.


Assuntos
Acanthamoeba/isolamento & purificação , Fontes Termais/parasitologia , Lobosea/isolamento & purificação , Naegleria/isolamento & purificação , Abastecimento de Água , Acanthamoeba/genética , Balamuthia mandrillaris/isolamento & purificação , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Irã (Geográfico) , Lobosea/genética , Naegleria/genética , Reação em Cadeia da Polimerase , Piscinas/normas , Abastecimento de Água/normas
8.
Exp Parasitol ; 183: 143-149, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28811103

RESUMO

Naegleria spp. are free-living amoebae belonging to the family Vahlkampfiidae, in the class Heterolobosea. Among the recognized species, Naegleria fowleri causes primary amoebic meningoencephalitis (PAM), while two other species, Naegleria australiensis and Naegleria italica, have been reported as pathogenic in experimental animals. Due to the thermotolerance properties of some species, geothermal water sources including hot springs represent suitable habitats for their proliferation. The main aim of this study was a year-round sampling in two geothermal springs in Central Italy, to investigate the presence of Naegleria spp. using PCR/DNA sequencing based methods. The affinities between the sequences generated here and others reported in the literature were explored by using POY, which implements the concept of dynamic homology. Naegleria australiensis, Naegleria italica, and Naegleria lovaniensis, plus an unassigned Naegleria spp. were detected. Indels in the rDNA ITS1 and ITS2 turned out to be critical to distinguish the three species and confirmed their phylogenetic relationships. This is the first molecular report on the Naegleria spp. occurrence in geothermal waters in Central Italy, coupled with a fine genetic characterization.


Assuntos
Fontes Termais/parasitologia , Naegleria/classificação , Naegleria/isolamento & purificação , Filogenia , DNA Espaçador Ribossômico/química , Itália , Naegleria/genética , Reação em Cadeia da Polimerase , Estações do Ano , Alinhamento de Sequência , Análise de Sequência de DNA
9.
Acta Parasitol ; 62(1): 104-109, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28030337

RESUMO

Potentially pathogenic Free-Living Amoebae include members belonging to Naegleria genus. The species N. fowleri is known worldwide as the causative agent of the lethal Primary Amoebic Meningoencephalitis (PAM). Only one clinical case of N. fowleri has been reported in Iran. Several species of Naegleria have been reported to be natural carriers of other potentially pathogenic microbial agents. The thermotolerance properties of this genus facilitates their presence in geothermal water sources including hot springs and spas. In the current study water samples were collected from 22 therapeutic hot springs, Northern Iran and investigated for the presence of Naegleria spp. using morphological keys and PCR/DNA sequencing based methods. Incubation of collected samples were done at both 30°C and 45°C in order to detect Naegleria spp. and N. fowleri, respectively. Thermotolerance assay and flagellation tests were also performed. The obtained results revealed that 54% of the investigated water samples were positive for Naegleria spp. including N. australiensis, N. americana, N. dobsoni, N. pagei, N. polaris and N. fultoni. The pathogenic N. fowleri was not detected. The most detected Naegleria was belonged to N. australiensis. This is the first report on the Naegleria spp. occurrence in hot springs in Northern Iran showing that most of the surveyed hot spring sources were contaminated with non-pathogenic Naegleria spp. However, due to the recent report of PAM in the country, further studies to investigate the presence of pathogenic N. fowleri in the environment and clinical samples is needed in the region and worldwide.


Assuntos
Fontes Termais/parasitologia , Naegleria/isolamento & purificação , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Irã (Geográfico)
10.
Int J Med Microbiol ; 306(6): 443-51, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27288243

RESUMO

Legionella pneumophila, the causative agent of Legionnaires disease, is naturally found in aquatic habitats. The intracellular life cycle within protozoa pre-adapted the "accidental" human pathogen to also infect human professional phagocytes like alveolar macrophages. Previous studies employing the model organism Caenorhabditis elegans suggest that also nematodes might serve as a natural host for L. pneumophila. Here, we report for the first time from a natural co-habitation of L. pneumophila and environmental nematode species within biofilms of a warm water spring. In addition, we identified the protozoan species Oxytricha bifaria, Stylonychia mytilus, Ciliophrya sp. which have never been described as potential interaction partners of L. pneumophila before. Modeling and dissection of the Legionella-protozoa-nematode interaction revealed that C. elegans ruptures Legionella-infected amoebal cells and by this means incorporate the pathogen. Further infection studies revealed that the macrophage infectivity potentiator (Mip) protein of L. pneumophila, which is known to bind collagen IV during human lung infection, promotes the colonization of the intestinal tract of L4 larvae of C. elegans and negatively influences the life span of the worms. The Mip-negative L. pneumophila mutant exhibited a 32-fold reduced colonization rate of the nematodes after 48h when compared to the wild-type strain. Taken together, these studies suggest that nematodes may serve as natural hosts for L. pneumophila, promote their persistence and dissemination in the environment, and co-evolutionarily pre-adapt the pathogen for interactions with extracellular constituents of human lung tissue.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cilióforos/fisiologia , Fontes Termais/microbiologia , Fontes Termais/parasitologia , Legionella/fisiologia , Nematoides/fisiologia , Animais , Cilióforos/crescimento & desenvolvimento , Cilióforos/microbiologia , Interações Hospedeiro-Parasita , Legionella/crescimento & desenvolvimento , Interações Microbianas , Nematoides/crescimento & desenvolvimento , Nematoides/microbiologia
12.
Parasitol Res ; 114(1): 311-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25352239

RESUMO

Naegleria fowleri is found in most geothermal baths of Guadeloupe and has been responsible for the death of a 9-year-old boy who swam in one of these baths in 2008. We wanted to determine the origin for the presence of this amoeba in the water. Water samples were taken at the origin of the geothermal sources and at the arrival in the baths. After filtration, cultures were made and the number of Naegleria present was determined using the most probable number method. Soil samples collected in the proximity of the baths were also tested for the presence of thermophilic amoebae. The species identification was obtained by PCR. During three consecutive months, no Naegleria could be found at the origin of any geothermal source tested. In contrast, N. fowleri was isolated at least once in all baths at the arrival of the water, except one. Thermophilic amoebae could be found in each soil sample, especially near the baths located at a lower altitude, but N. fowleri was only isolated near two baths, which were also the baths most often contaminated with this species. So it appears that the contamination of the water with N. fowleri occurs after emerging from the geothermal source when the water runs over the soil. Therefore, it should be possible to reduce the concentration of N. fowleri in the geothermal baths of Guadeloupe to for example less than 1 N. fowleri/10 L by installing a pipeline between the geothermal sources and the baths and by preventing flooding water from entering the baths after rainfall. By taking these measures, we were able to eliminate N. fowleri from a pool located inside a reeducation clinic.


Assuntos
Fontes Termais/parasitologia , Naegleria fowleri/isolamento & purificação , Recreação , Solo/parasitologia , Água/parasitologia , Altitude , Filtração , Guadalupe , Reação em Cadeia da Polimerase , Chuva , Piscinas
13.
J Eukaryot Microbiol ; 62(3): 374-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25382699

RESUMO

We studied the protist grazers of Boiling Springs Lake (BSL), an acid geothermal feature in Lassen Volcanic National Park, using a combination of culture and genetic approaches. The major predator in BSL is a vahlkampfiid ameba closely related (95% 18S+ITS rRNA identity) to Tetramitus thermacidophilus, a heterolobose ameboflagellate recently isolated from volcanic geothermal acidic sites in Europe and Russia, as well as an uncultured heterolobosean from the nearby Iron Mountain acid mine drainage site. Tetramitus thermacidophilus strain BSL is capable of surviving the physical extremes of BSL, with optimal growth at 38-50 °C and pH 2-5. This bacterivore also ingested conidiospores of the ascomycete Phialophora sp., but ultrastructural observations reveal the latter may not be readily digested, and conidia were not separable from the ameoboflagellate culture, suggesting a possible symbiosis. DGGE fingerprint transects studies showed the organism is restricted to near-lake environs, and we detected an average of ~500 viable cysts/cm(3) sediment on the shoreline. Other grazing protists were isolated from lakeshore environments, including the lobose amebae Acanthamoeba sp. and Hartmannella sp., and the kinetoplastid flagellate Bodo sp., but none could tolerate both low pH and high temperature. These appear to be restricted to cooler near lake geothermal features, which also contain other potential grazer morphotypes observed but not successfully cultured, including ciliates, euglenids, testate amebae, and possible cercozoans. We compare the food web of BSL with other acidic or geothermal sites, and discuss the impact of protists in this unique environment.


Assuntos
Biota , Eucariotos/classificação , Eucariotos/isolamento & purificação , Cadeia Alimentar , Fontes Termais/parasitologia , Lagos/parasitologia , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Eucariotos/genética , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Temperatura
14.
Trans R Soc Trop Med Hyg ; 109(3): 221-4, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25424836

RESUMO

BACKGROUND: Environmental sources are potential sources for the transmission of Acanthamoeba in humans and other mammals. METHODS: A total of 50 water samples from hot springs and swimming pools, and 50 soil samples were taken from Adana, Afyon, Kutahya, Mersin and Nigde provinces in Turkey. Samples were analysed using 18S rRNA-DNA sequencing. RESULTS: Acanthamoeba griffini (T3), Acanthamoeba castellanii (T4) and Acanthamoeba jacobsi (T15) were found in water samples. Acanthamoeba griffini (T3) and Acanthamoeba castellanii (T4) were detected in soil samples. CONCLUSIONS: In Turkey, this was the first time that Acanthamoeba jacobsi (T15) was detected in water samples.


Assuntos
Acanthamoeba/isolamento & purificação , Fontes Termais/parasitologia , Piscinas , Abastecimento de Água , Água/parasitologia , Acanthamoeba/genética , Animais , Genes de RNAr , Genótipo , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA/métodos , Turquia
15.
Sci Total Environ ; 499: 212-9, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25192927

RESUMO

Free-living amoebae (FLA) are ubiquitous in various aquatic environments. Several amoebae species are pathogenic and host other pathogens such as Legionella, but the presence of FLA and its parasites as well as the related infection risk are not well known. In this study, the presence of pathogenic FLA and Legionella in various water bodies was investigated. Water samples were collected from a river, intake areas of drinking water treatment plants, and recreational hot spring complexes in central and southern Taiwan. A total of 140 water samples were tested for the presence of Acanthamoeba spp., Naegleria spp., Vermamoeba vermiformis, and Legionella. In addition, phylogenetic characteristics and water quality parameters were also assessed. The pathogenic genotypes of FLA included Acanthamoeba T4 and Naegleria australiensis, and both were abundant in the hot spring water. In contrast, Legionella pneumophila was detected in different aquatic environments. Among the FLA assessed, V. vermiformis was most likely to coexist with Legionella spp. The total bacteria level was associated with the presence of FLA and Legionella especially in hot spring water. Taken together, FLA contamination in recreational hot springs and drinking water source warrants more attention on potential legionellosis and amoebae infections.


Assuntos
Amoeba/crescimento & desenvolvimento , Água Potável/microbiologia , Água Potável/parasitologia , Legionella/crescimento & desenvolvimento , Microbiologia da Água , Amoeba/classificação , Monitoramento Ambiental , Fontes Termais/microbiologia , Fontes Termais/parasitologia , Legionella/classificação , Medição de Risco , Taiwan , Purificação da Água
16.
Int J Parasitol ; 43(9): 691-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23665128

RESUMO

Naegleria fowleri can cause primary amoebic meningoencephalitis, a rapidly developing and highly lethal infectious disease. The first confirmed case of primary amoebic meningoencephalitis in Taiwan was reported in November 2011, in which the patient visited a thermal spring recreational area 1 week prior to hospitalisation. Water sampling was performed to verify the presence of Naegleria at the facility. According to our results, 32% and 20% of recreational water samples were contaminated with Naegleria spp. and Acanthamoeba spp., respectively. The genotypes of Naegleria identified at the hot spring included N. fowleri, Naegleria australiensis and Naegleria lovaniensis. Using PCR, it was determined that the strain of N. fowleri in one sample possessed the same genotype 2 as the clinical isolate. Thus, the thermal spring was suggested to be the likely source of infection. This is the first known instance of simultaneously isolating N. fowleri from both a patient as well as from a hot spring in Taiwan. Following this initial study, the pools at the thermal spring recreational area were drained, scrubbed and disinfected, and a follow-up study was performed 1 month later. Naegleria fowleri was not detected in follow-up testing; however, other Naegleria spp. were identified. We postulate that the biofilm in the waterlines may have provided a reservoir for free-living amoebae. The presence/absence of Acanthamoeba and Naegleria spp. did not differ significantly with any measured parameters related to water quality; however, a high percentage of the thermal water pool samples were contaminated with Naegleria or Acanthamoeba. Thus, amoebic contamination may present a serious threat to the health of humans who engage in leisure activities at thermal springs.


Assuntos
Infecções Protozoárias do Sistema Nervoso Central/parasitologia , Fontes Termais/parasitologia , Naegleria fowleri/isolamento & purificação , Água/parasitologia , Animais , Infecções Protozoárias do Sistema Nervoso Central/epidemiologia , Genótipo , Humanos , Naegleria fowleri/genética , Taiwan/epidemiologia
17.
Lett Appl Microbiol ; 56(1): 1-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23020241

RESUMO

UNLABELLED: Naegleria spp. is a free-living amoeba that can be found in the natural environment. A number of Naegleria spp. can cause fatal infections in the central nervous system in humans and animals, and the most important source of infection is through direct water contact. In this study, water samples from various thermal springs were taken from four thermal spring areas. Naegleria spp. was detected via culture confirmation and molecular taxonomic identification. Among the 60 samples obtained, Naegleria spp. was identified in 26 (43·3%) samples. The identified species included Naegleria australiensis, Naegleria gruberi, Naegleria lovaniensis and Naegleria mexicana. The presence of living Naegleria spp. was significantly associated with elevated pH value in the water sample. SIGNIFICANCE AND IMPACT OF STUDY: In this study, we examined the presence of living Naegleria spp. in thermal spring waters in south-eastern Taiwan. Naegleria spp. was isolated and culture-confirmed from thermal spring water. Naegleria fowleri was not found in all water samples, and Naegleria australiensis was the most common Naegleria genotype.


Assuntos
Fontes Termais/parasitologia , Naegleria/isolamento & purificação , Água/parasitologia , Concentração de Íons de Hidrogênio , Naegleria/genética , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Taiwan , Água/química , Qualidade da Água
18.
Environ Sci Pollut Res Int ; 20(5): 3098-106, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23054762

RESUMO

Legionella are commonly found in natural and man-made aquatic environments and are able to inhabit various species of protozoa. The relationship between the occurrence of Legionella spp. within protozoa and human legionellosis has been demonstrated; however, the proportions of intracellular and extracellular Legionella spp. in the aquatic environment were rarely reported. In this study, we developed a new method to differentiate intracellular and extracellular Legionella spp. in the aquatic environment. Water samples from three thermal spring recreational areas in southeastern Taiwan were collected and analyzed. For each water sample, concurrent measurements were performed for Legionella spp. and their free-living amoebae hosts. The overall detection rate was 32 % (16/50) for intracellular Legionella spp. and 12 % (6/50) for extracellular Legionella spp. The most prevalent host of Legionella spp. was Hartmannella vermiformis. The identified Legionella spp. differed substantially between intracellular and extracellular forms. The results showed that it may be necessary to differentiate intracellular and extracellular forms of Legionella spp.


Assuntos
Carga Bacteriana/métodos , Fontes Termais/microbiologia , Fontes Termais/parasitologia , Legionella/classificação , Legionella/isolamento & purificação , Lobosea/microbiologia , Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Acanthamoeba/microbiologia , Contagem de Colônia Microbiana , Hartmannella/genética , Hartmannella/isolamento & purificação , Hartmannella/microbiologia , Legionella/genética , Legionella/fisiologia , Lobosea/genética , Lobosea/isolamento & purificação , Naegleria/genética , Naegleria/isolamento & purificação , Naegleria/microbiologia , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência , Taiwan
19.
J Water Health ; 10(4): 650-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23165720

RESUMO

This study was conducted to address the distribution of Acanthamoeba genotypes in therapeutic hot springs in Iran. Sixty water and sediment samples were collected from bicarbonate, sulphur, and sodium chloride thermal springs in the northwest. All hot springs examined are used mainly for health purposes in Iran. Acanthamoeba were identified by both morphology and PCR (polymerase chain reaction). Genotype identification was based on the sequencing of a highly variable and informative region of Diagnostic Fragment 3 (stem 29-1 of 18S rRNA gene) within Acanthamoeba-specific amplimer (ASA.S1). Twenty percent of hot springs were contaminated with thermotolerant Acanthamoeba belonging to the potentially pathogenic T4 and T3 genotypes. A high number (91.7%) of strains showed growth at 37 °C, and eight isolates showed growth at 42 °C. A single isolate (HSNW2) was detected in waters at 70 °C. The presence of thermotolerant Acanthamoeba highlights a risk factor for susceptible individuals, as Acanthamoeba-related keratitis continues to rise in Iran. Periodic surveillance of thermal waters as well as improved filtration and disinfection is recommended to prevent disease related to pathogenic Acanthamoeba. This is the first comprehensive molecular study of Acanthamoeba genotypes in hot springs in Iran and the first to report the occurrence of the T3 genotype (corresponding to Acanthamoeba griffini) in thermal water sources in this country.


Assuntos
Acanthamoeba/genética , Acanthamoeba/isolamento & purificação , Fontes Termais/parasitologia , Acanthamoeba/classificação , Sequência de Bases , Genótipo , Irã (Geográfico) , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Recreação , Alinhamento de Sequência
20.
Exp Parasitol ; 130(4): 354-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22366362

RESUMO

Acanthamoeba species are free-living amoebae found in a range of environments. Within this genus, a number of species are recognized as human pathogens, potentially causing Acanthamoeba keratitis, granulomatous amoebic encephalitis, and chronic granulomatous lesions. In this study, 60 water samples were taken from four thermal spring recreation areas in southern Taiwan. We detected living Acanthamoeba spp. based on culture-confirmed detection combined with the molecular taxonomic identification method. Living Acanthamoeba spp. were detected in nine (15%) samples. The presence or absence of Acanthamoeba spp. in the water samples depended significantly on the pH value. The most frequently identified living Acanthamoeba genotype was T15 followed by T4, Acanthamoeba spp., and T2. Genotypes T2, T4, and T15 of Acanthamoeba, are responsible for Acanthamoeba keratitis as well as granulomatous amoebic encephalitis, and should therefore be considered a potential health risk associated with human activities in thermal spring environments.


Assuntos
Acanthamoeba/isolamento & purificação , Fontes Termais/parasitologia , Acanthamoeba/classificação , Acanthamoeba/genética , Ceratite por Acanthamoeba/parasitologia , DNA de Protozoário/química , Eletroforese em Gel de Ágar , Encefalite/parasitologia , Genótipo , Fontes Termais/química , Fontes Termais/normas , Concentração de Íons de Hidrogênio , Filogenia , Reação em Cadeia da Polimerase , Taiwan , Temperatura
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