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1.
Environ Pollut ; 266(Pt 3): 115143, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32682184

RESUMO

Land use/Land cover (LULC) associated with Cryptosporidium sp. and Giardia sp. quantification and distribution can provide identification of the environmental circulation patterns of these parasites. The aim of this research was to relate the occurrence and circulation of these parasites to the LULC watershed with poor sanitation infrastructure and livestock as important economic activity. The study involved 11 municipalities in the state of São Paulo, located in southeastern Brazil. Sampling was carried out at the catchment sites of each water supply on a monthly basis, starting in December 2014 and lasting until November 2015, totalizing 128 samples. Protozoans were quantified according to the 1623.1 US. EPA Method. For watershed delimitation, the hydrographic network was extracted from the hydrology tool of ArcGIS 10.1. The frequency of occurrence of these pathogens and the high concentrations were evidenced in the municipality with the largest urban area (16.2%) and intense livestock activity (39%) near the catchment site. The municipality that showed the lowest frequency of occurrence presented the smallest urban area (0.87%) and absence of livestock activity near the catchment site. The high concentration of pathogens suggests a correlation between the impact on water supply networks and river basin degradation caused by urban activity and livestock.


Assuntos
Criptosporidiose , Cryptosporidium , Animais , Brasil , Cidades , Giardia , Abastecimento de Água
2.
Environ Pollut ; 266(Pt 3): 115144, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32673973

RESUMO

Giardia is a protozoan parasite of primary concern for the drinking water industry. High contact times are required for Giardia inactivation by chlorination, while ozonation may be effective at much lower Ct products. In this study, we have assessed the occurrence of Giardia cysts in raw water, and in chlorinated or ozonated water from a drinking water treatment plant (DWTP) in Brazil, over a 16-month period. Moreover, we analyzed the effects of primary disinfection on cysts, and calculated the infection risk caused by the occurrence of Giardia cysts in raw water, chlorinated or ozonated water. Furthermore, we assessed the correlation of Giardia cysts with indicator bacteria in raw water. Data referring to concentration of Giardia cysts in raw water showed adherence to a gamma distribution at a significance level α = 0.05. The detection frequency and the mean concentration of Giardia cysts were higher in raw water (86.6%, 26 cysts∙L-1), than in chlorinated (46.1%, 15.7 cysts·L-1) or ozonated water (43.5%, 11.1 cysts·L-1). Overall, Giardia non-viable cysts were detected more frequently in ozonated water (80%) than in chlorinated water (68.2%) or raw water (37.7%). Ozonation and chlorination resulted, respectively, in ≈27.5- and ≈13- fold reduction of Giardia infection risk, when compared to the risk calculated for raw water. Total coliform and Escherichia coli proved to be suitable surrogates to predict the occurrence of Giardia cysts in raw surface water, however, the indicator bacteria may not be suitable surrogates to predict the disinfection of Giardia cysts, as no correlation was found between indicator bacteria and Giardia cysts in treated water. To our knowledge, this is the first study reporting the efficacy of chlorine and ozone at Ct products actually applied at a full-scale drinking water treatment plant against Giardia cysts naturally occurring in the source water, i.e. real situation. Ozonation has proven more efficient than chlorination against Giardia cysts in surface water. Escherichia coli proved to be suitable surrogate to predict Giardia cysts in raw surface water.


Assuntos
Água Potável/análise , Giardíase , Ozônio , Purificação da Água , Brasil , Giardia , Humanos , Abastecimento de Água
3.
PLoS Negl Trop Dis ; 14(6): e0008378, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32516309

RESUMO

The aim of this study was to determine the prevalence and risk factors of the main enteric parasitic infections that affect children and dogs in the municipality of Ilhéus, Bahia, Brazil; and to identify the geopolitical areas that should receive priority interventions to combat them. Between March and November 2016, fecal samples of 143 dogs and 193 children aged 1 month to 5 years were collected in 40 rural and semirural communities using a systematic sampling approach, stratified by district. Samples were collected by legal guardians of the children and / or dog owners. Eggs, larvae, cysts and oocysts of parasites were concentrated by centrifugal-flotation and centrifugal-sedimentation, and acid-resistant staining was used to visualize parasites. One hundred and thirty-two children (68.4%), 111 dogs (77.6%) and 199 (73.7%) dog fecal samples collected from streets were parasitized. Giardiasis, cryptosporidiosis, amoeba infections and hookworm were the most frequent infections in all studied populations, in addition to trichuriasis in dogs and ascaridiasis in children. A predominance of Giardia and hookworms was observed in children and dogs, respectively. The coastal districts of Aritaguá, Olivença and the main district had a higher parasitic diversity and overlapping of important potential zoonotic infections. Age over one year (p<0.001), adjusted OR = 3.65; 95% CI = 1.86-7.16) and income below the minimum monthly salary (p = 0.02, adjusted OR = 2.78, 95% CI = 1.17-6.59) were the main factors associated with intestinal parasitic infections in children and dogs, respectively. The coastal districts of Aritaguá and Olivença and the main district should be prioritized through enteric disease control programs, and the factors associated with infections must be considered in the design of health interventions in these districts. The integration between affirmative income actions and investments to improve the health infrastructure of these communities may work more effectively than current preventive measures to combat enteric parasites.


Assuntos
Amebíase/epidemiologia , Doenças do Cão/epidemiologia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/veterinária , Amebíase/veterinária , Animais , Brasil/epidemiologia , Pré-Escolar , Estudos Transversais , Criptosporidiose/epidemiologia , Cães , Fezes/parasitologia , Feminino , Giardia , Giardíase/epidemiologia , Giardíase/veterinária , Infecções por Uncinaria/epidemiologia , Humanos , Lactente , Masculino , Análise Multivariada , Oocistos , Parasitos , Prevalência , Fatores de Risco , Zoonoses/parasitologia
4.
Parasitol Res ; 119(7): 2149-2157, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32424553

RESUMO

Global investigations have implicated water buffalo (Bubalus bubalis) as a potential source of zoonotic Cryptosporidium and Giardia parasites which may pose a threat to human health. In Australia, buffalo are a feral pest that have colonised the floodplains, wetlands and woodlands of Indigenous owned and managed Arnhem Land, in tropical monsoonal Northern Australia. Indigenous people from the remote community Ngukurr have raised concerns about the potential threat to their health from shared use of surface waters inhabited by buffalo, in the South East Arnhem Land Indigenous Protected Area (SEAL IPA), Northern Australia. Surface waters are valued by local Indigenous people for spiritual and customary reasons, bush foods, medicines and drinking water. Here, we used molecular methods to characterise Cryptosporidium spp. and Giardia duodenalis assemblages from feral water buffalo living in the SEAL IPA to determine potential zoonotic risks to health of Indigenous people through co-use of surface water billabongs. Buffalo faecal DNA was screened for Cryptosporidium and Giardia using the 18S rRNA gene. Giardia were also screened using Glutamate hydrogenase (gdh) and ßeta-giardin (ß-giardin) genes. DNA sequencing identified C. ryanae in 9.9% (31/313) and G. duodenalis assemblage E 1.9% (6/313) in buffalo. Cryptosporidium ryanae is not considered zoonotic and G. duodenalis assemblage E is a livestock assemblage that has been reported in humans. Carriage of G. duodenalis assemblage E in buffalo may present a disease risk for Indigenous people utilising billabongs, according to customary practice.


Assuntos
Búfalos/parasitologia , Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Animais , Animais Selvagens , Austrália , Cryptosporidium/classificação , Cryptosporidium/genética , Fezes/parasitologia , Giardia/classificação , Giardia/genética , Humanos , Proteínas de Protozoários/genética , RNA Ribossômico 18S/genética
5.
Vet Parasitol ; 281: 109115, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32361137

RESUMO

Giardia spp. and Cryptosporidium spp. are common gastrointestinal parasites with the potential for zoonotic transmission. This study aimed to (1) determine the genotypes occurring in dogs and coyotes occupying a similar urban area; (2) determine if these hosts were infected with potentially zoonotic genotypes; (3) provide baseline molecular data. In August and September 2012, 860 dog owners living in neighborhoods bordering six urban parks in Calgary, Alberta, Canada, provided faecal samples from their dogs. From March 2012 through July 2013, 193 coyote faeces were also collected from five of six of the same parks. Direct immunofluorescence microscopy (DFA) indicated that Giardia spp. and Cryptosporidium spp. infected a total of 64 (7.4%) and 21 (2.4%) dogs, as well as 15 (7.8%) and three (1.6%) coyotes, respectively. Semi-nested, polymerase chain reactions targeting the 16S small-subunit ribosomal ribonucleic acid (SSU rRNA) and 18S SSU rRNA genes of Giardia spp. and Cryptosporidium spp., respectively, were conducted on samples that screened positive by DFA, and products were sequenced and genotyped. Dogs were infected with Giardia intestinalis canid-associated assemblages C (n = 14), D (n = 13), and Cryptosporidium canis (n = 3). Similarly, G. intestinalis assemblages C (n = 1), D (n = 1) and C. canis (n = 1), were detected in coyotes, as well as G. intestinalis assemblage A (n = 1) and Cryptosporidium vole genotype (n = 1). Dogs and coyotes were predominantly infected with host-specific genotypes and few potentially zoonotic genotypes, suggesting that they may not represent a significant risk for zoonotic transmission of these parasites in urban areas where these hosts are sympatric.


Assuntos
Coiotes/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/genética , Doenças do Cão/parasitologia , Giardia/genética , Giardíase/parasitologia , Alberta/epidemiologia , Animais , Doenças do Cão/epidemiologia , Cães , Fezes/parasitologia , Genes de Protozoários/genética , Genes de RNAr/genética , Genótipo , Giardíase/epidemiologia , Parques Recreativos , Zoonoses/epidemiologia , Zoonoses/parasitologia
6.
Parasitol Res ; 119(6): 1847-1855, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32350588

RESUMO

Cryptosporidium and Giardia are well-known parasitic protozoans responsible for waterborne and foodborne diarrhoeal diseases. However, data are not available on market vegetables contaminated with Cryptosporidium and Giardia in China. In the present study, 642 different vegetable samples were collected from Xining City street vendors in the Qinghai Province to study the Cryptosporidium and Giardia contamination rates via PCR and sequence analyses. Cryptosporidium spp. and Giardia duodenalis were detected in 16 (2.5%) and 73 (11.4%) samples, respectively. Two species of Cryptosporidium, C. parvum (n = 11) and C. andersoni (n = 5), were identified. G. duodenalis assemblage B was identified in almost all positive samples (n = 72), except one sample that contained G. duodenalis assemblage E. We report on the rate of Cryptosporidium and Giardia contamination in vegetables for the first time from the Qinghai Tibetan Plateau Area (QTPA) in China.


Assuntos
Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Oocistos/isolamento & purificação , Verduras/parasitologia , Animais , China , Cryptosporidium/genética , Contaminação de Alimentos , Giardia/genética , Giardia lamblia/genética , Reação em Cadeia da Polimerase , Tibet
7.
Environ Pollut ; 264: 114766, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32417583

RESUMO

Cryptosporidium and Giardia are important parasites due to their zoonotic potential and impact on human health, often causing waterborne outbreaks of disease. Detection of (oo)cysts in water matrices is challenging and few countries have legislated water monitoring for their presence. The aim of this study was to investigate the presence and origin of these parasites in different water sources in Northern Greece and identify interactions between biotic/abiotic factors in order to develop risk-assessment models. During a 2-year period, using a longitudinal, repeated sampling approach, 12 locations in 4 rivers, irrigation canals, and a water production company, were monitored for Cryptosporidium and Giardia, using standard methods. Furthermore, 254 faecal samples from animals were collected from 15 cattle and 12 sheep farms located near the water sampling points and screened for both parasites, in order to estimate their potential contribution to water contamination. River water samples were frequently contaminated with Cryptosporidium (47.1%) and Giardia (66.2%), with higher contamination rates during winter and spring. During a 5-month period, (oo)cysts were detected in drinking-water (<1/litre). Animals on all farms were infected by both parasites, with 16.7% of calves and 17.2% of lambs excreting Cryptosporidium oocysts and 41.3% of calves and 43.1% of lambs excreting Giardia cysts. The most prevalent species identified in both water and animal samples were C. parvum and G. duodenalis assemblage AII. The presence of G. duodenalis assemblage AII in drinking water and C. parvum IIaA15G2R1 in surface water highlights the potential risk of waterborne infection. No correlation was found between (oo)cyst counts and faecal-indicator bacteria. Machine-learning models that can predict contamination intensity with Cryptosporidium (75% accuracy) and Giardia (69% accuracy), combining biological, physicochemical and meteorological factors, were developed. Although these prediction accuracies may be insufficient for public health purposes, they could be useful for augmenting and informing risk-based sampling plans.


Assuntos
Criptosporidiose , Cryptosporidium , Água Potável , Animais , Bovinos , Giardia , Grécia , Humanos , Aprendizado de Máquina , Oocistos , Ovinos
8.
Parasitol Res ; 119(7): 2275-2286, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451716

RESUMO

Giardia and Cryptosporidium infections are common in cats, but knowledge is limited about their clinical importance, risk factors, and the role of cats as a reservoir for human infections. Here, we collected faeces and questionnaire data from 284 cats from shelters and veterinary clinics in the Copenhagen Metropolitan Region (= study population). Additionally, 33 samples were analysed separately from catteries with gastrointestinal clinical signs (= cases). (Oo-)cysts were quantified by immunofluorescence microscopy. All Giardia (n = 34) and Cryptosporidium (n = 29) positive samples were analysed by sequencing of the 18S rRNA, gdh and hsp70 loci, and co-infections were detected by McMaster/inverted microscopy. In the study population, 7.0% and 6.7% were positive for Giardia and Cryptosporidium respectively; 48.5% and 36.4% of the breeder cats (cases) were infected. Increased odds of diarrhoea were demonstrated in Giardia (p = 0.0008) and Cryptosporidium (p = 0.034) positive cats. For Giardia, the odds were positively correlated with infection intensity. Co-infection with Cryptosporidium (OR 12.79; p < 0.001), parasitic co-infections other than Cryptosporidium (OR 5.22; p = 0.009), no deworming (OR 4.67; p = 0.035), and male sex (OR 3.63; p = 0.025) were risk factors for Giardia. For Cryptosporidium, co-infection with Giardia was the only risk factor (OR 11.93; p < 0.0001). Genotyping revealed G. duodenalis assemblages A and F, and C. felis, all of them previously detected in humans. In conclusion, excretion of Giardia and Cryptosporidium was associated with clinical disease. Although a public health risk is likely, studies including larger sample sizes, more discriminatory markers and samples from other animals and humans are needed to reveal the full zoonotic potential.


Assuntos
Doenças do Gato/parasitologia , Criptosporidiose/epidemiologia , Giardíase/epidemiologia , Giardíase/veterinária , Animais , Gatos , Criptosporidiose/parasitologia , Cryptosporidium/genética , Dinamarca/epidemiologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Fezes/parasitologia , Feminino , Giardia/genética , Giardíase/parasitologia , Proteínas de Choque Térmico HSP70/genética , Humanos , Masculino , RNA Ribossômico 18S/genética , Fatores de Risco , Desidrogenase do Álcool de Açúcar/genética
9.
Wiad Lek ; 73(2): 380-383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32248179

RESUMO

OBJECTIVE: The aim was to perform systematic review of genitourinary protozoan invasion and analyze their pathogenicity and the ability to influence the genitourinary infections. PATIENTS AND METHODS: Materials and methods: For systematic review of papers the EMBASE and PubMed databases were searched. We also reviewed our own pilot studies using real-time polymerase chain reaction (PCR) to determine Trichomonas tenax, Pentatrichomonas hominis and Giardia lamblia. CONCLUSION: Conclusions: Trichomonas tenax, Pentatrichomonas hominis, Giardia lamblia can cause genitourinary invasion in addition to Trichomonas vaginalis. Their eradication is obligatory at least for not keeping intact pathogenic microorganisms phagocyted by Trichomonas spp. Defining the protozoan forms is important in preventing of genital infections recurrences and reinfections.


Assuntos
Trichomonas vaginalis , Genitália , Giardia , Humanos
10.
Environ Sci Pollut Res Int ; 27(18): 23129-23140, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32333348

RESUMO

Some Brazilian beaches are impacted by raw or poorly treated sewage. Thus, users (beachgoers, sports people, and children) are exposed to pathogens, which pose health concerns. This study aimed to estimate the probability of infection and disease by Giardia and Cryptosporidium, using the quantitative microbial risk assessment (QMRA), for three groups of bathers: children, adults, and open water swimmers. The concentrations of (oo)cysts were taken from a study run by CETESB (Environmental Company of Sao Paulo State) throughout 2011 and 2012, in which 203 samples were collected monthly and analyzed for (oo)cysts of Giardia and Cryptosporidium. Giardia was present in 43% of the samples, while Cryptosporidium in 13%. Infection probability was higher in beaches with more positive samples for Giardia cysts for the group of open water swimmers. In some cases, the highest annual risk obtained for giardiasis and cryptosporidiosis was 2.4 × 10-1 and 8.9 × 10-3 for open water swimmers, respectively, exceeding the incidence results found in the epidemiological study run in summer of 1999 in São Paulo state coast. The results bring insights to improve environmental quality in order to protect tourists' and residents' wellbeing.


Assuntos
Criptosporidiose , Cryptosporidium , Giardíase , Adulto , Animais , Brasil , Criança , Giardia , Humanos , Oocistos
11.
Water Res ; 175: 115698, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32220670

RESUMO

Co-infection with multiple pathogens, especially the spread of Giardia and Cryptosporidium in source water among those with immunodeficiency, is common worldwide, which will result in an increase in overall risk. In this study, the quantitative microbial risk assessment model was used to estimate the cumulative risk of co-infection with Giardia and Cryptosporidium promoted by HIV, considering age sensitivity. The sensitivity of population segments with different ages was estimated by the optimization method, based on clinical data of cryptosporidiosis and giardiasis with age structure. The factors of co-infection enhancement were used to quantify HIV synergism with the action of other pathogens. The removal rates of Giardia and Cryptosporidium through water treatment were estimated by a model involving turbidity and particles. The results showed that children (0-4 years) were 17.911-fold more sensitive to infection with Giardia than adults (15-64 years), and that with Cryptosporidium was 10.592-fold. Removal rates of these parasites in water treatment plants in major cities in China were estimated to be 2.03 log10. Considering the HIV-synergistic and age-susceptibility effects, the cumulative risk of exposure to Giardia or Cryptosporidium was about 38.781 × 10-6DALYs (Disability-adjusted life years) per person per year, which was much higher than the reference risk level recommended by the World Health Organization (10-6DALYs). The methodology and results of this study will be useful in better evaluating and reducing the burden due to infection of Giardia and/or Cryptosporidium in China and other countries.


Assuntos
Coinfecção , Criptosporidiose , Cryptosporidium , Giardíase , Infecções por HIV , Adulto , Animais , Criança , China , Giardia , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Medição de Risco
12.
J Environ Manage ; 261: 110268, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148324

RESUMO

Some of the microorganisms present in urban wastewater, which include intestinal protozoa and nematodes, can be pathogenic. Their (oo)cyst and egg transmissible stages are very resistant to environmental stresses and disinfectants and they are therefore difficult to remove. Thus, they can constitute a health risk if water or sludge obtained in the purification of wastewater is reused for agricultural purposes. In this context, the presence of intestinal protozoa and nematodes were studied in influents, effluents and sludge from five wastewater treatment plants (WWTPs) in the north of Spain by optical microscopy and PCR techniques. The removal efficiency of different wastewater treatments was also compared. The presence of protozoa has increased among the population discharging waste to WWTPs in recent years. Cryptosporidium spp., Giardia duodenalis, Entamoeba spp. and nematodes were detected in all of the WWTPs. Indeed, this is the first report of Entamoeba histolytica and Entamoeba moshkovskii in Spanish WWTPs. The water treatments studied showed different removal efficiencies for each species of intestinal protozoa, with the aerated lagoons providing the best results. (Oo)cysts were also detected in sludge even after aerobic digestion and dehydration. To avoid risks, (oo)cyst viability should be analysed whenever the sludge is to be used as a fertilizer. This study reinforces the necessity of establishing legal limits on the presence of protozoa in WWTP effluents and sludges, especially if reuse is planned. Further studies are necessary for a better understanding of the presence and behaviour of intestinal parasites.


Assuntos
Criptosporidiose , Cryptosporidium , Nematoides , Animais , Giardia , Esgotos , Espanha , Eliminação de Resíduos Líquidos , Águas Residuárias
13.
Adv Parasitol ; 107: 25-96, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32122531

RESUMO

Giardia lamblia is a widespread parasitic protist with a complex MT cytoskeleton that is critical for motility, attachment, mitosis and cell division, and transitions between its two life cycle stages-the infectious cyst and flagellated trophozoite. Giardia trophozoites have both highly dynamic and highly stable MT organelles, including the ventral disc, eight flagella, the median body and the funis. The ventral disc, an elaborate MT organelle, is essential for the parasite's attachment to the intestinal villi to avoid peristalsis. Giardia's four flagellar pairs enable swimming motility and may also promote attachment. They are maintained at different equilibrium lengths and are distinguished by their long cytoplasmic regions and novel extra-axonemal structures. The functions of the median body and funis, MT organelles unique to Giardia, remain less understood. In addition to conserved MT-associated proteins, the genome is enriched in ankyrins, NEKs, and novel hypothetical proteins that also associate with the MT cytoskeleton. High-resolution ultrastructural imaging and a current inventory of more than 300 proteins associated with Giardia's MT cytoskeleton lay the groundwork for future mechanistic analyses of parasite attachment to the host, motility, cell division, and encystation/excystation. Giardia's unique MT organelles exemplify the capacity of MT polymers to generate intricate structures that are diverse in both form and function. Thus, beyond its relevance to pathogenesis, the study of Giardia's MT cytoskeleton informs basic cytoskeletal biology and cellular evolution. With the availability of new molecular genetic tools to disrupt gene function, we anticipate a new era of cytoskeletal discovery in Giardia.


Assuntos
Giardia/citologia , Giardia/metabolismo , Microtúbulos/metabolismo , Giardia/classificação , Giardia/ultraestrutura , Microtúbulos/química , Microtúbulos/ultraestrutura , Organelas/química , Organelas/metabolismo , Organelas/ultraestrutura
14.
15.
Vet Clin North Am Food Anim Pract ; 36(1): 223-238, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029186

RESUMO

Cryptosporidium and Giardia are ubiquitous protozoan parasites that infect a broad range of vertebrate hosts, including domestic and wild animals as well as humans. Both parasites are of medical and veterinary importance. Infections with Cryptosporidium and Giardia in ruminants are associated with diarrhea outbreaks, mainly in young animals. Ruminants are potential sources of infection for humans because some species of Cryptosporidium and assemblages of Giardia duodenalis have been isolated from both ruminants and humans. Knowledge of these parasites has greatly expanded in the last 2 decades from simple microscopic observations of organisms to the knowledge acquired from molecular tools.


Assuntos
Criptosporidiose/parasitologia , Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Giardíase/parasitologia , Giardíase/veterinária , Animais , Fezes/parasitologia , Humanos , Prevalência , Ruminantes/parasitologia
16.
Exp Parasitol ; 210: 107848, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004534

RESUMO

Marine bivalves are usually cultivated in shallow, estuarine waters where there is a high concentration of nutrients. Many micro-pollutants, including the protozoan parasites Giardia duodenalis and Cryptosporidium spp., which also occur in such environments, may be concentrated in shellfish tissues during their feeding process. Shellfish can thus be considered as vehicles for foodborne infections, as they are usually consumed lightly cooked or raw. Therefore, the main objective of this study was to investigate the presence of both parasites in Mediterranean mussels, Mytilus galloprovincialis that are cultivated in Thermaikos Gulf, North Greece, which is fed by four rivers that are contaminated with both protozoa. Moreover, the occurrence of these protozoa was monitored in treated wastewaters from 3 treatment plants that discharge into the gulf. In order to identify potential sources of contamination and to estimate the risk for human infection, an attempt was made to genotype Giardia and Cryptosporidium in positive samples. Immunofluorescence was used for detection and molecular techniques were used for both detection and genotyping of the parasites. In total, 120 mussel samples, coming from 10 farms, were examined for the presence of both protozoa over the 6-month farming period. None of them were found positive by immunofluorescence microscopy for the presence of parasites. Only in 3 mussel samples, PCR targeting the GP60 gene detected Cryptosporidium spp. DNA, but sequencing was not successful. Thirteen out of 18 monthly samples collected from the 3 wastewater treatment plants, revealed the presence of Giardia duodenalis cysts belonging to sub-assemblage AII, at relatively low counts (up to 11.2 cysts/L). Cryptosporidium oocysts (up to 0.9 oocysts/L) were also detected in 4 out of 8 samples, although sequencing was not successful at any of the target genes. At the studied location and under the sampling conditions described, mussels tested were not found to be harboring Giardia cysts and the presence of Cryptosporidium was found only in few cases (by PCR detection only). Our results suggest that the likelihood that mussels from these locations act as vehicles of human infection for Giardia and Cryptosporidium seems low.


Assuntos
Bivalves/parasitologia , Cryptosporidium/isolamento & purificação , Doenças Transmitidas por Alimentos/parasitologia , Giardia/isolamento & purificação , Animais , Criptosporidiose/transmissão , Cryptosporidium/genética , DNA de Protozoário/isolamento & purificação , Giardia/genética , Giardíase/transmissão , Grécia , Humanos , Oocistos/isolamento & purificação , Reação em Cadeia da Polimerase , Rios/parasitologia , Águas Residuárias/parasitologia
17.
Parasitol Res ; 119(3): 1125-1137, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31907666

RESUMO

Giardiasis, one of the most common causes of diarrhoeal disease, is caused by gastrointestinal protozoal parasites of the genus Giardia. Metronidazole is the most commonly used drug to treat giardiasis. However, metronidazole resistance is increasingly common, making the development of new anti-giardial drugs a high priority. A panel of 11 compounds previously identified in T. ferdinandiana fruit extracts were investigated for the ability to inhibit G. duodenalis proliferation. Eight of the 11 compounds inhibited the growth of all three G. duodenalis strains. 2,3-Dihydroxyphenyl B-D-glucopyranosiduronic acid (DPGA) was the most potent anti-giardial compound, with IC50 values as low as 126 µM (38 µg/mL). Notably, DPGA inhibited a metronidazole-resistant G. duodenalis strain with similar activity as determined for the metronidazole-sensitive strains. Furthermore, the activity of DPGA was greatly potentiated when it was tested in combination with ascorbic acid, to approximately 17 µM (5 µg/mL) for the metronidazole-sensitive G. duodenalis strains and 40 µM (12 mg/mL) for the resistant strain. The T. ferdinandiana tannins (gallic acid and chebulic acid) were moderate inhibitors of G. duodenalis growth when tested in combination with ascorbic acid, although they had only low levels of activity when tested alone. All of the tested compounds (and their combinations with ascorbic acid) displayed low toxic effects and all compounds are conformed to Lipinski's rules of 5 with few violations, indicating their potential as drug leads and chemotherapies for the treatment and prevention of giardiasis.


Assuntos
Ácido Ascórbico/farmacologia , Giardia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Terminalia/química , Animais , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Resistência a Medicamentos , Etanol/química , Etilenoglicóis/química , Ácidos Graxos/química , Giardíase/tratamento farmacológico , Giardíase/parasitologia , Humanos , Concentração Inibidora 50 , Metronidazol/farmacologia
18.
Environ Pollut ; 257: 113545, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31733962

RESUMO

This study aimed to quantify Giardia and Cryptosporidium in disinfected water reuse samples from two Wastewater Treatment Plants (A and B), which were quantified by USEPA 1693/2014 Method. Giardia was found in 35.8% of the total samples (<0.03 to 16 cysts/L) while Cryptosporidium in 30.2% (<0.03 to 25.8 oocysts/L). This study highlights the presence of both parasites in water for reuse despite treatment processes for their removal, which means there is a challenge to overcome. Their presence is preoccupant even though in low concentrations because the infectivity dose is low coupled with high prevalence in the global population. The practice of water recycling is valuable for sustainable water management and it is in line with Sustainable Developments Goals but should not threaten human health. Tackling this issue is more critical in developing countries because treatment processes are often more limited, the monitoring data from water reuse are not always available, the lack of regulation for water reuse quality and the lack of planning for its sustainable usage.


Assuntos
Cryptosporidium , Giardia , Oocistos , Eliminação de Resíduos Líquidos , Águas Residuárias/parasitologia , Animais , Criptosporidiose , Humanos , Reciclagem , Água , Purificação da Água
19.
Exp Parasitol ; 209: 107824, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31870927

RESUMO

Giardiasis and cryptosporidiosis are recognized by the WHO as important emerging diseases of the 21st century. Symptoms are similar and include diarrhoea and vomiting, which may be severe, even life-threatening, for the immunocompromised and children under five years of age. Between 2013 and 2017, the Institute for Public Health in Serbia recorded 10 waterborne epidemics that manifested as gastrointestinal disease. Routine testing for enteropathogenic bacteria and viruses did not identify the aetiological agents of these outbreaks. As water is not examined for the presence of protozoa in Serbia, we performed a pilot study to analyse samples from four major rivers and their tributaries using a newly implemented methodology for detection of Giardia and Cryptosporidium, based on the ISO 15553:2006 standard. Using immunofluorescence microscopy, Giardia was detected in 10 out of the 31 samples, Cryptosporidium in five, while two samples were positive for both. Presence of G. duodenalis gDNA was confirmed by amplification of the ß-giardin gene in eight samples, of which one and two, respectively, were identified by RFLP as potentially zoonotic assemblages A and B. The results suggest that surface water in Serbia may be a potential source of infection and call for more in-depth studies using sophisticated molecular tools.


Assuntos
Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Rios/parasitologia , Animais , Cryptosporidium/genética , Proteínas do Citoesqueleto/genética , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Técnicas de Genotipagem , Giardia/classificação , Giardia/genética , Humanos , Complexo Mediador/genética , Microscopia de Fluorescência , Projetos Piloto , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética , RNA Ribossômico/genética , Sérvia
20.
Water Sci Technol ; 80(6): 1022-1030, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31799946

RESUMO

Separate sewer systems collect and discharge rainwater directly into surface water bodies. In residential areas covering moderate traffic load these are alternative drainage routes to avoid combined sewer overflow discharge and to keep rivers clean as required by the EU Water Framework Directive. This overflow's microbial quality, however, needs to be evaluated, since stormwater run-offs are potential pathways for pathogens into river systems. Between 2010 and 2016, two separate sewer systems in North Rhine-Westphalia (Germany) were investigated. The stormwater outflow was sampled during discharge events and microbiologically analysed. The results showed high concentrations of Escherichia coli (1,100-1,100,000 CFU/100 mL) and Clostridium perfringens (20-13,000 CFU/100 mL). Campylobacter and Salmonella were detected in 97% and 43% of the samples. Giardia cysts were more often detected (31.6%) than Cryptosporidium oocysts (10.5%). The sources of human pathogens in rainwater run-off are heterogeneous. While roads have already been declared as chemical polluters via rainwater run-off, our study detected supplementary pollution of mainly faecal microorganisms. Presumably, failed connections in the sewer system itself are important sources of human pathogens. We suggest treatment of stormwater run-offs before being discharged into the river system.


Assuntos
Monitoramento Ambiental , Microbiologia da Água , Animais , Alemanha , Giardia , Humanos , Chuva
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