خيارات البحث
النتائج 1 - 8 من 8
Assessment of airborne enteric viruses emitted from wastewater treatment plant: Atmospheric dispersion model, quantitative microbial risk assessment, disease burden
2019
Pasalari, Hasan | Ataei-Pirkooh, Angila | Aminikhah, Mahdi | Jafari, Ahmad Jonidi | Farzadkia, Mahdi
From a health prospective, it is critical to provide a comprehensive model which integrates all the parameters involved in virus transmission and its consequences on human body. In order to estimate the health risks, for workers and residents, associated with an exposure airborne viruses emitted from a wastewater treatment (WWTP), the concentration levels of viruses in emitted bioaerosols over a twelve-month period were measured by real-time polymerase chain reaction (RT-PCR). A combined Gaussian plum dispersion model and quantitative microbial risk assessment (QMRA) with Monte-Carlo simulation served as suitable explanatory tools to estimate the risk of acquiring gastrointestinal illness (GI) due to exposure to air containing Rotavirus (RoV) and Norovirus (NoV) bioaerosols. Additionally, DALY metric was applied to quantify the disability and mortality for workers and residents. RoV and NoV were detected above aeration tank with annual mean concentration 27 and 3099 (Viruses/m³.h), respectively. The medium calculated DALY indicator based on viral loads in contaminant source (RoV:5.76 × 10⁻² and NoV:1.23 × 10⁻¹) and estimated in different distances away (300–1000 m) (RoV:2.87 × 10⁻²- 2.75 × 10⁻² and NoV:1.14 × 10⁻¹-1.13 × 10⁻¹) were markedly higher than the threshold values recommended by US EPA (10⁻⁴ DALY pppy) and WHO (10⁻⁶ DALY pppy). The sensitivity analysis highlighted dose exposure and disease burden per case (DBPC) as two most influential factors for both workers and residents following exposure to two pathogens of concern. Due to high resistance and high concentration in the environment, the presence of RoV and NoV can intensify the consequences of diarrhea especially for children under five years of age; A comprehensible and transparent presentation of DALYs and QMRA can help decision makers and responsibilities to justify the priorities of exposure to wastewater in comparison with other risks of daily life.
اظهر المزيد [+] اقل [-]On the risks from sediment and overlying water by replenishing urban landscape ponds with reclaimed wastewater
2018
Ao, Dong | Chen, Rong | Wang, Xiaochang C. | Liu, Yanzheng | Dzakpasu, Mawuli | Zhang, Lu | Huang, Yue | Xue, Tao | Wang, Nan
The extensive use of reclaimed wastewater (RW) as a source of urban landscape pond replenishment, stimulated by the lack of surface water (SW) resources, has raised public concern. Greater attention should be paid to pond sediments, which act as ‘sinks’ and ‘sources’ of contaminants to the overlying pond water. Three ponds replenished with RW (RW ponds) in three Chinese cities were chosen to investigate 22 indices of sediment quality in four categories: eutrophication, heavy metal, ecotoxicity and pathogens risk. RW ponds were compared with other ponds of similar characteristics in the same cities that were replenished with SW (SW ponds). Our results show a strong impact of RW to the eutrophication and pathogenic risks, which are represented by organic matter, water content, total nitrogen, total phosphorus and phosphorus fractions, and pathogens. In particular, total phosphorus concentrations in the RW pond sediments were, on average, 50% higher than those of SW ponds. Moreover, the content of phosphorus, extracted by bicarbonate/dithionite (normally represented by BD-P) and NaOH (NaOH-P), were 2.0- and 2.83-times higher in RW ponds, respectively. For pathogens, the concentrations of norovirus and rotavirus in RW pond sediments were, on average, 0.52 and 0.30- log times those of SW ponds. The duration of RW replenishment was proved to have a marked impact on the eutrophication and pathogens risks from sediments. The continued use of RW for replenishment increases the eutrophication risk, and the pathogens risk, especially by viral pathogens, becomes greater.
اظهر المزيد [+] اقل [-]Haze is an important medium for the spread of rotavirus
2016
Ye, Qing | Fu, Jun-feng | Mao, Jian-hua | Shen, Hong-qiang | Chen, Xue-jun | Shao, Wen-Xia | Shang, Shi-qiang | Wu, Yi-feng
This study investigated whether the rotavirus infection rate in children is associated with temperature and air pollutants in Hangzhou, China. This study applied a distributed lag non-linear model (DLNM) to assess the effects of daily meteorological data and air pollutants on the rotavirus positive rate among outpatient children. There was a negative correlation between temperature and the rotavirus infection rate. The impact of temperature on the detection rate of rotavirus presented an evident lag effect, the temperature change shows the greatest impact on the detection rate of rotavirus approximate at lag one day, and the maximum relative risk (RR) was approximately 1.3. In 2015, the maximum cumulative RR due to the cumulative effect caused by the temperature drop was 2.5. Particulate matter (PM) 2.5 and PM10 were the primary air pollutants in Hangzhou. The highest RR of rotavirus infection occurred at lag 1–1.5 days after the increase in the concentration of these pollutants, and the RR increased gradually with the increase in concentration. Based on the average concentrations of PM2.5 of 53.9 μg/m3 and PM10 of 80.6 μg/m3 in Hangzhou in 2015, the cumulative RR caused by the cumulative effect was 2.5 and 2.2, respectively. The current study suggests that temperature is an important factor impacting the rotavirus infection rate of children in Hangzhou. Air pollutants significantly increased the risk of rotavirus infection, and dosage, lag and cumulative effects were observed.
اظهر المزيد [+] اقل [-]Microbiological Contaminants in Drinking Water: Current Status and Challenges
2022
Kristanti, Risky Ayu | Hadibarata, Tony | Syafrudin, Muhammad | Yılmaz, Murat | Abdullah, Shakila
Water is a vital resource to every living thing on the earth. Once the water is contaminated (physically, chemically, biologically, or radiologically), it brought negative impacts to the living thing. This paper provides a brief review of the characterization of biological pollutants in drinking water and their effects on human health. Some biological contamination was detected in water resources such as pathogenic bacteria (Escherichia coli, Vibrio cholerae, Salmonella, etc.), viruses (hepatitis A virus, hepatitis E virus, rotavirus, etc.), parasites (Giardia, Entamoeba, Cyclospora, etc.), and parasitic worm (Ascaris lumbricoides, Ancylostoma duodenale, Strongyloides stercoralis, etc.). The diseases were significantly prevalent in developing countries due to limited access to clean water and poor sanitation. Most of the diseases had common symptoms such as diarrhea, fever, and body and muscle aches that were transmitted to humans through the fecal–oral route. About 1.7 billion children were affected by diarrhea each year and about 525,000 of the children died each year. Besides, nearly 1 million adults were killed by diarrhea every year. Some treatment was implemented to remove the biological contamination in drinking water, such as oxidation treatment, ultraviolet radiation, distillation, biologically active carbon filtration, electrochemical, and nanotechnology.
اظهر المزيد [+] اقل [-]The contribution of bovines to human health against viral infections
2021
Saied, AbdulRahman A. | Metwally, Asmaa A. | Mohamed, Hams M.A. | Haridy, Mohie A.M.
In the last 40 years, novel viruses have evolved at a much faster pace than other pathogens. Viral diseases pose a significant threat to public health around the world. Bovines have a longstanding history of significant contributions to human nutrition, agricultural, industrial purposes, medical research, drug and vaccine development, and livelihood. The life cycle, genomic structures, viral proteins, and pathophysiology of bovine viruses studied in vitro paved the way for understanding the human counterparts. Calf model has been used for testing vaccines against RSV, papillomavirus vaccines and anti-HCV agents were principally developed after using the BPV and BVDV model, respectively. Some bovine viruses-based vaccines (BPIV-3 and bovine rotaviruses) were successfully developed, clinically tried, and commercially produced. Cows, immunized with HIV envelope glycoprotein, produced effective broadly neutralizing antibodies in their serum and colostrum against HIV. Here, we have summarized a few examples of human viral infections for which the use of bovines has contributed to the acquisition of new knowledge to improve human health against viral infections covering the convergence between some human and bovine viruses and using bovines as disease models. Additionally, the production of vaccines and drugs, bovine-based products were covered, and the precautions in dealing with bovines and bovine-based materials.
اظهر المزيد [+] اقل [-]Presence of bacteroidales as a predicator of human enteric viruses in Haihe River of Tianjin City, China
2019
Zhou, Shuqing | Yang, Dong | Xu, Qunying | Yang, Zhongwei | Jin, Min | Yin, Jing | Wang, Huaran | Zhou, Kun | Wang, Lianqi | Li, Junwen | Shen, Zhiqiang
Traditional microbe indicators including total bacteria, total coliforms, fecal coliforms, Escherichia coli, enterococci, and F+ coliphage are all frequently used to characterize the microbial contamination state of water bodies for their correlation with pathogenic bacteria. However, these indicators have a poor relationship with viruses, which pose serious threat to economic and human health. Alternative indicators such as bacteroidales may be suitable complementary alternatives to traditional microbe indicators and are being increasingly reported. In the present study, water was analyzed for selected sites along Haihe River in Tianjin for traditional indicators, an alternative indicator (bacteroidales), pathogenic bacteria (Salmonella, Escherichia coli (E. coli) O157:H7, and Vibrio parahaemolyticus), viruses (enteric adenovirus, norovirus, enterovirus, poliovirus and rotavirus), and physicochemical parameters. Results indicated that traditional microbe indicators detected in this study showed good correlation with pathogenic bacteria, and the alternative indicator (bacteroidales) had a surprisingly good relationship with viral presence. We propose that bacteroidales might be a suitable complementary indicator for viral contamination in water bodies.
اظهر المزيد [+] اقل [-]Preliminary evaluation of BioFire FilmArray® Gastrointestinal Panel for the detection of noroviruses and other enteric viruses from wastewater and shellfish
2018
Gyawali, Pradip | Croucher, Dawn | Hewitt, Joanne
The BioFire FilmArray® Gastrointestinal Panel was evaluated for the rapid detection of adenovirus, astrovirus, norovirus, rotavirus and sapovirus from influent and effluent wastewater and shellfish. The multiplex BioFire FilmArray® Gastrointestinal Panel compared well to singleplex qPCR/RT-qPCR methods for the detection of adenovirus, astrovirus, rotavirus and sapovirus from influent and effluent wastewater samples. However, the BioFire FilmArray® Gastrointestinal Panel showed poor performance for the detection of norovirus, significantly underestimating its presence in wastewater and shellfish samples when compared with the singleplex norovirus GI and GII RT-qPCR assays. Therefore, improvement on detection efficiency for norovirus from environmental and food samples is necessary before using results from the FilmArray® Gastrointestinal Panel to assess associated public health risks.
اظهر المزيد [+] اقل [-]Optimization of sampling strategy to determine pathogen removal efficacy of activated sludge treatment plant
2017
Sidhu, Jatinder P. S. | Ahmed, Warish | Palmer, Andrew | Smith, Kylie | Hodgers, Leonie | Toze, Simon
Large-scale wastewater schemes rely on multi-barrier approach for the production of safe and sustainable recycled water. In multi-barrier wastewater reclamation systems, conventional activated sludge process (ASP) often constitutes a major initial treatment step. The main aim of this research was to determine most appropriate sampling approach to establish pathogen removal efficacy of ASP. The results suggest that ASP is capable of reducing human adenovirus (HAdV) and polyomavirus (HPyV) by up to 3 log₁₀. The virus removal data suggests that HAdV removal is comparable to somatic bacteriophage belonging to Microviridae family. Due to the high removal of Escherichia coli (>3 log₁₀) and very poor correlation with the enteric virus, it is not recommended that E. coli be used as a surrogate for enteric virus removal. The results also demonstrated no statistically significant differences (t test, P > 0.05) in calculated log removal values (LRVs) for HAdV, HPyV, and Microviridae from samples collected on hydraulic retention time (HRT) or simultaneous paired samples collected for influent and effluent. This indicates that a more practical approach of simultaneous sampling for influent and effluent could be used to determine pathogen removal efficiency of ASP. The results also suggest that a minimum of 10, preferably 20 samples, are required to fully capture variability in the removal of virus. In order to cover for the potential seasonal prevalence of viruses such as norovirus and rotavirus, sampling should be spread across all seasons.
اظهر المزيد [+] اقل [-]