Prevalence of potentially pathogenic free-living amoebae from Acanthamoeba and Naegleria genera in non-hospital, public, internal environments from the city of Santos, Brazil
Abstract:Acanthamoeba and Naegleria species are free-living amoebae (FLA) found in a large variety of natural habitats. The prevalence of such amoebae was determined from dust samples taken from public non-hospital internal environments with good standards of cleanliness from two campuses of the same University in the city of Santos (SP), Brazil, and where young and apparently healthy people circulate. The frequency of free-living amoebae in both campuses was 39% and 17% respectively, with predominance of the genus Aca… Show more
“…These low concentrations are used to prevent corrosion of the machines, according to the instructions from the machines' distributors (personal communication). In addition, cysts of these amoebae are resistant to changes in temperature and pH and exposure to chlorine, detergents and common disinfectants [29]. The contamination of hemodialysis hydraulic systems could be partly attributed to biofilm formation as a result of water stagnation in the long bending drain connecting the water treatment unit to the hemodialysis unit [8].…”
Ubiquitous free-living amoebae of the genus Acanthamoeba can be pathogenic and can serve as carriers of other pathogenic organisms. These amoebae are potentially dangerous when they contaminate health facilities, and these organisms may act as a source of infection for medical personnel and those seeking medical care. The purpose of the present study was to evaluate the extent to which Acanthamoeba species contaminate hemodialysis and dental units in Alexandria, Egypt. Seventy samples were collected aseptically from these systems and cultivated on non-nutrient agar at room temperature, followed by morphological confirmation of the identity of Acanthamoeba using trichrome-stained smears. This study revealed that 42.9% of water samples from the hydraulic systems of both hemodialysis and dental units were positive for Acanthamoeba, with no statistically significant difference between the two unit types or between pre-and post-disinfection samples for each type of unit. The surgical category of dental clinics had the highest contamination rate (72.7%), whereas no contamination was observed for water samples from pediatric dentistry clinics. In conclusion, the hydraulic systems of hemodialysis and dental units in Alexandria are contaminated with Acanthamoeba species, and to minimize the risk of human infections, there is an urgent need to implement effective preventative measures, such as the installation of water filtration units.
“…These low concentrations are used to prevent corrosion of the machines, according to the instructions from the machines' distributors (personal communication). In addition, cysts of these amoebae are resistant to changes in temperature and pH and exposure to chlorine, detergents and common disinfectants [29]. The contamination of hemodialysis hydraulic systems could be partly attributed to biofilm formation as a result of water stagnation in the long bending drain connecting the water treatment unit to the hemodialysis unit [8].…”
Ubiquitous free-living amoebae of the genus Acanthamoeba can be pathogenic and can serve as carriers of other pathogenic organisms. These amoebae are potentially dangerous when they contaminate health facilities, and these organisms may act as a source of infection for medical personnel and those seeking medical care. The purpose of the present study was to evaluate the extent to which Acanthamoeba species contaminate hemodialysis and dental units in Alexandria, Egypt. Seventy samples were collected aseptically from these systems and cultivated on non-nutrient agar at room temperature, followed by morphological confirmation of the identity of Acanthamoeba using trichrome-stained smears. This study revealed that 42.9% of water samples from the hydraulic systems of both hemodialysis and dental units were positive for Acanthamoeba, with no statistically significant difference between the two unit types or between pre-and post-disinfection samples for each type of unit. The surgical category of dental clinics had the highest contamination rate (72.7%), whereas no contamination was observed for water samples from pediatric dentistry clinics. In conclusion, the hydraulic systems of hemodialysis and dental units in Alexandria are contaminated with Acanthamoeba species, and to minimize the risk of human infections, there is an urgent need to implement effective preventative measures, such as the installation of water filtration units.
“…However, these earlier studies focused on only a single ophthalmology hospital and analyzed five dust samples of ophthalmology wards, which contained the Acanthamoeba T4 genotype (Niyyati et al 2009a). The present study was a comprehensive survey with 70 samples and also included biofilms as a potential source of proliferation of FLA. Airborne dust, combined with high levels of air pollution, is frequent in Tehran, enabling cysts to be transferred by visitors from outside to the indoor environment of hospital wards (Teixeira et al 2009;Chan et al 2011;Costa et al 2010).…”
This study investigated the occurrence of free-living amoebae (FLA) in immunodeficiency wards of hospitals in Tehran, Iran. A total of 70 dust and biofilm samples from wards serving transplant, pediatric (malignancies), HIV, leukemia and oncology patients of five university hospitals were collected and examined for the presence of FLA using culturing and molecular approaches. Based on the morphology of the amoebae in plate cultures, primer sets were applied for molecular identification of Acanthamoeba, vahlkampfiid amoebae and Hartmannella. Out of 70 samples, 37 (52.9%) were positive for FLA. Acanthamoeba belonged to the T4 genotype was the most prevalent isolate. Presence of the T4 genotype on medical instruments, including an oxygen mask in an isolation room of an immunodeficiency pediatric ward, should be of concern for health authorities. Acanthamoeba T5 genotypes, Hartmannella vermiformis, and Vahlkampfia avara were also present. These results highlight a clear need for greater attention to improved disinfection, especially where susceptible patients, such as those who are immune-suppressed, are served. To our knowledge, this is the first report of these FLA in immunodeficiency wards in Iran, and also the first to identify Acanthamoeba T5, Hartmannella, and Vahlkampfia in moist habitats, such as biofilms, in this country.
“…In fact, there are few reports of detection of free-living amoebae in indoor dust (Carlesso et al, 2010;Lasjerdi et al, 2011;Niyyati et al, 2009;Teixeira et al, 2009). In fact, there are few reports of detection of free-living amoebae in indoor dust (Carlesso et al, 2010;Lasjerdi et al, 2011;Niyyati et al, 2009;Teixeira et al, 2009).…”
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.