Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
1.
Environ Sci Pollut Res Int ; 30(29): 74386-74397, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: covidwho-2326985

RESUMEN

In the context of the COVID-19 pandemic, antiviral drugs (AVDs) were heavily excreted into wastewater and subsequently enriched in sewage sludge due to their widespread use. The potential ecological risks of AVDs have attracted increasing attention, but information on the effects of AVDs on sludge anaerobic digestion (AD) is limited. In this study, two typical AVDs (lamivudine and ritonavir) were selected to investigate the responses of AD to AVDs by biochemical methane potential tests. The results indicated that the effects of AVDs on methane production from sludge AD were dose- and type-dependent. The increased ritonavir concentration (0.05-50 mg/kg TS) contributed to an 11.27-49.43% increase in methane production compared with the control. However, methane production was significantly decreased at high lamivudine doses (50 mg/kg TS). Correspondingly, bacteria related to acidification were affected when exposed to lamivudine and ritonavir. Acetoclastic and hydrotropic methanogens were inhibited at a high lamivudine dose, while ritonavir enriched methylotrophic and hydrotropic methanogens. Based on the analysis of intermediate metabolites, the inhibition of lamivudine and the promotion of ritonavir on acidification and methanation were confirmed. In addition, the existence of AVDs could affect sludge properties. Sludge solubilization was inhibited when exposed to lamivudine and enhanced by ritonavir, perhaps caused by their different structures and physicochemical properties. Moreover, lamivudine and ritonavir could be partially degraded by AD, but 50.2-68.8% of AVDs remained in digested sludge, implying environmental risks.


Asunto(s)
COVID-19 , Aguas del Alcantarillado , Humanos , Aguas del Alcantarillado/química , Anaerobiosis , Biocombustibles , Eliminación de Residuos Líquidos/métodos , Antivirales/farmacología , Ritonavir , Lamivudine/metabolismo , Pandemias , Metano/metabolismo , Reactores Biológicos
2.
Sci Total Environ ; 851(Pt 2): 158310, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: covidwho-2004487

RESUMEN

The potential risk of SARS-CoV-2 in treated effluent from a wastewater treatment plant (WWTP) is concerned since SARS-CoV-2 is contained in wastewater during the COVID-19 outbreak. However, the removal of SARS-CoV-2 in WWTP has not been well investigated. The objectives of this study were (i) to clarify the removal performance of SARS-CoV-2 during wastewater treatment, (ii) to compare the removal performance of different secondary treatment processes, and (iii) to evaluate applicability of pepper mild mottle of virus (PMMoV) as a performance indicator for the reduction of SARS-CoV-2 RNA in wastewater treatment. Influent wastewater, secondary-treatment effluent (before chlorination), and final effluent (after chlorination) samples were collected from a WWTP from May 28 to September 24, 2020, during the COVID-19 outbreak in Japan. The target WWTP had three parallel treatment systems employing conventional activated sludge (CAS), anaerobic-anoxic -oxic (A2O), and membrane bioreactor (MBR) processes. SARS-CoV-2 in both the liquid and solid fractions of the influent wastewater was concentrated and quantified using RT-qPCR. SARS-CoV-2 in treated effluent was concentrated from 10 L samples to achieve a detection limit as low as 10 copies/L. The log reduction value (LRV) of SARS-CoV-2 was 2.7 ± 0.86 log10 in CAS, 1.6 ± 0.50 log10 in A2O, and 3.6 ± 0.62 log10 in MBR. The lowest LRV observed during the sampling period was 2.8 log10 in MBR, 1.2 log10 in CAS, and 1.0 log10 in A2O process, indicating that the MBR had the most stable reduction performance. PMMoV was found to be a good indicator virus to evaluate reduction performance of SARS-CoV-2 independent of the process configuration because the LRV of PMMoV was significantly lower than that of SARS-CoV-2 in the CAS, A2O and MBR processes.


Asunto(s)
COVID-19 , Purificación del Agua , Humanos , Aguas del Alcantarillado , SARS-CoV-2 , Aguas Residuales , Anaerobiosis , ARN Viral , Reactores Biológicos , Eliminación de Residuos Líquidos
3.
Int J Environ Res Public Health ; 19(17)2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: covidwho-1997623

RESUMEN

The use of facial coverings has been amplified during the COVID-19 pandemic as a means to minimize the spread of disease. However, facial coverings may impede ventilation during high-intensity activity, leading to a reduction in cardiopulmonary exercise capacity. Thus, the purpose of this study was to determine the acute impact of different facial coverings on exercise performance in college-aged individuals during a 300-yard shuttle. It was hypothesized that the lowest heart rate (HR), completion time (CT), and rate of perceived exertion (RPE) would occur with no mask. Furthermore, it was hypothesized the SHEMA97 mask would have lower HR, CT, and RPE compared to surgical and fabric masks. Results showed the use of the fabric mask resulted in significantly higher HR compared to no mask (p = 0.006). The SHEMA97 mask resulted in faster CT and lower RPE compared to both the fabric and surgical masks (p < 0.001). All mask conditions yielded significantly higher levels of perceived discomfort than wearing no mask (p < 0.05). While the use of facial coverings can help prevent the spread of disease, their use during exercise may pose limitations to performance; however, the ability of the SHEMA97 to provide minimal changes to CT and RPE provides a promising option.


Asunto(s)
COVID-19 , Pandemias , Adulto , Anaerobiosis , Ejercicio Físico , Humanos , Máscaras , Pandemias/prevención & control , Adulto Joven
4.
Environ Res ; 214(Pt 4): 114057, 2022 11.
Artículo en Inglés | MEDLINE | ID: covidwho-1996149

RESUMEN

Since the COVID-19 outbreak has started in late 2019, SARS-CoV-2 has been widely detected in human stools and in urban wastewater. No infectious SARS-CoV-2 particles have been detected in raw wastewater until now, but it has been reported occasionally in human stools. This has raised questions on the fate of SARS-CoV-2 during wastewater treatment and notably in its end-product, wastewater treatment sludge, which is classically valorized by land spreading for agricultural amendment. In the present work, we focused on SARS-CoV-2 stability in wastewater treatment sludge, either during storage (4 °C, room temperature) or thermophilic anaerobic digestion (50 °C). Anaerobic digestion is one of the possible processes for sludge valorization. Experiments were conducted in laboratory pilots; SARS-CoV-2 detection was based on RT-quantitative PCR or RT-digital droplet PCR. In addition to SARS-CoV-2, Bovine Coronavirus (BCoV) particles were used as surrogate virus. The RNA from SARS-CoV-2 particles, inactivated or not, was close to the detection limit but stable in wastewater treatment sludge, over the whole duration of the assays at 4 °C (55 days) and at ambient temperature (∼20 °C, 25 days). By contrast, the RNA levels of BCoV and inactivated SARS-CoV-2 particles decreased rapidly during the thermophilic anaerobic digestion of wastewater treatment sludge lasting for 5 days, with final levels that were close to the detection limit. Although the particles' infectivity was not assessed, these results suggest that thermophilic anaerobic digestion is a suitable process for sludge sanitation, consistent with previous knowledge on other coronaviruses.


Asunto(s)
COVID-19 , Purificación del Agua , Anaerobiosis , Animales , COVID-19/epidemiología , Bovinos , Humanos , ARN , SARS-CoV-2/genética , Aguas del Alcantarillado , Aguas Residuales , Purificación del Agua/métodos
5.
Int J Environ Res Public Health ; 19(11)2022 05 25.
Artículo en Inglés | MEDLINE | ID: covidwho-1924228

RESUMEN

The COVID-19 pandemic required local confinement measures reducing sport practice with possible consequences on the athletes' performances. Furthermore, anaerobic detraining was underestimated and poorly known in adolescents. This article aimed to assess the effects of SARS-CoV-2 infection and 1-month COVID-19 confinement on jump testing in young elite soccer players despite a 1-month multimodal training program followed by a 1-month soccer retraining period. Thirty-one elite soccer players aged 14 were included; 16 were infected by the SARS-CoV-2 and compared with 15 non-infected elite soccer players before and after 1 month of COVID-19 confinement, and after 1 month of a soccer retraining period. Squat jumps (SJ), countermovement jumps with (CMJs) and without arm swinging (CMJ) and multiple consecutive jumps (stiffness) were used to explore the anaerobic performances. Analysis of variance for repeated measures was used to compare the positive and negative SARS-CoV-2 groups, taking into account the confinement period (low training) and the retraining soccer period. The jump tests were not altered in the positive SARS-CoV-2 group compared to the negative SARS-CoV-2 group after confinement (SJ: 31.6 ± 5.6 vs. 32.7 ± 3.7; CMJ: 34.1 ± 6.9 vs. 34.2 ± 2.6; CMJs: 38.6 ± 6.8 vs. 40.3 ± 3.9; stiffness: 28.5 ± 4.3 vs. 29.1 ± 3.7) and at 1 month of this period (SJ: 33.8 ± 5.5 vs. 36.2 ± 4.6; CMJ: 34.7 ± 5.5 vs. 36.4 ± 3.5; CMJs: 40.4 ± 6.7 vs. 42.7 ± 5.5; stiffness: 32.6 ± 4.7 vs. 34.0 ± 4.3). The SARS-CoV-2 infection had no consequence on anaerobic performances assessed by jump tests in adolescent soccer players. The adolescents' growth could explain the absence of alteration of jump performances during the COVID-19 confinement. These results can be useful to manage the recovery of the anaerobic fitness after SARS-CoV-2 infection occurring in adolescent athletes.


Asunto(s)
COVID-19 , Fútbol , Adolescente , Anaerobiosis , COVID-19/epidemiología , Prueba de Esfuerzo/métodos , Humanos , Fuerza Muscular , Pandemias , SARS-CoV-2
6.
Water Res ; 212: 118069, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: covidwho-1621091

RESUMEN

Investigating waterborne viruses is of great importance to minimizing risks to public health. Viruses tend to adsorb to sludge particles from wastewater processes by electrostatic and hydrophobic interactions between virus, aquatic matrix, and particle surface. Sludge is often re-used in agriculture; therefore, its evaluation is also of great interest to public health. In the present study, a pilot scale system treating real domestic wastewater from a large city in Brazil was used to evaluate the removal, the overall reduction, and liquid-solid partitioning of human adenovirus (HAdV), the novel coronavirus (SARS-CoV-2) and fecal indicators (F-specific coliphages and E. coli). The system consists of a high-rate algal pond (HRAP) post-treating the effluent of an upflow anaerobic sludge blanket (UASB) reactor. Samples were collected from the influent and effluent of each unit, as well as from the sludge of the UASB and from the microalgae biomass in the HRAP. Pathogens and indicators were quantified by quantitative polymerase chain reaction (qPCR) (for HAdV), qPCR with reverse transcription (RTqPCR) (for SARS-CoV-2), the double agar plaque assay (for coliphages), and the most probable number (MPN) method (for E. coli). The removal and overall reduction of HAdV and SARS-CoV-2 was greater than 1-log10. Almost 60% of remaining SARS-CoV-2 RNA and more than 70% of remaining HAdV DNA left the system in the sludge, demonstrating that both viruses may have affinity for solids. Coliphages showed a much lower affinity to solids, with only 3.7% leaving the system in the sludge. The system performed well in terms of the removal of organic matter and ammoniacal nitrogen, however tertiary treatment would be necessary to provide further pathogen reduction, if the effluent is to be reused in agriculture. To our knowledge, this is the first study that evaluated the reduction and partitioning of SARS-CoV-2 and HAdV through the complete cycle of a wastewater treatment system consisting of a UASB reactor followed by HRAPs.


Asunto(s)
COVID-19 , Purificación del Agua , Adenoviridae , Anaerobiosis , Reactores Biológicos , Escherichia coli , Humanos , ARN Viral , SARS-CoV-2 , Aguas del Alcantarillado , Eliminación de Residuos Líquidos
7.
Anaerobe ; 77: 102509, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: covidwho-1588336

RESUMEN

Anaerobic cocci are common anaerobic isolates. Numerous genera of anaerobic cocci have been reported in both urinary tract microbiota, mainly of females, and in cases of urinary tract infections (UTIs), predominantly in patients with comorbidities, when no facultatively anaerobic bacteria were detected from the urine samples. UTIs caused by anaerobic cocci have been reported in >7% in some studies. As the routine diagnostic methods may be insufficient to detect and identify the anaerobic cocci in patients with UTIs, enhanced quantitative urine culture (EQUC) can give better results. EQUC is performed by plating urine samples onto different media to be incubated in both aerobic and anaerobic conditions with a prolonged incubation time. Other newer methods such as 16S rRNA gene sequencing, qualitative PCR and Next Generation Sequencing can also be considered. Anaerobic cocci such as Peptoniphilus, Parvimonas, Anaerococcus and Finegoldia spp. were found in patients with bacteremia of urinary source. A fatal outcome has been reported in a diabetic patient with emphysematous pyelonephritis caused by Finegoldia magna and Candida parapsilosis due to a delay in seeking hospital care during the COVID-19 pandemic. In specific cases such as of chronic infections, immunosuppression, comorbidity, advanced age, following urological tract manipulations and negative culture results for usual uropathogens, it may be advisable to use suprapubic aspiration cultured in both aerobic and anaerobic condition or EQUC using media which support the relative slow growing anaerobic cocci as well.


Asunto(s)
COVID-19 , Infecciones Urinarias , Femenino , Humanos , Bacterias Anaerobias/genética , ARN Ribosómico 16S/genética , Anaerobiosis , Pandemias , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/microbiología
8.
Environ Res ; 206: 112585, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: covidwho-1587836

RESUMEN

Anaerobic digestion is a consolidated technology to convert sewage sludge and other organic wastes into biogas and a nutrient-rich fertilizer (i.e. digestate). The origin of sewage sludge does not exclude the potential presence of pathogens (e.g. Salmonella spp. and SARS-CoV-2) in mature digestate that hence could represent a source of sanitary concerns when it is spread on soil for agriculture purpose. Therefore, an experimental study aimed at proving the sanitizing effect of a full scale thermophilic high solids anaerobic digestion process was conducted by monitoring the hygienic characteristics of mature digestate. Although Salmonella spp. was detected in the sewage sludge fed to the full scale plant, the anaerobic digestion treatment demonstrated sanitization capacity since the monitored pathogens were never found in the mature digestate over the entire duration of the monitoring survey. Furthermore, tests on the regrowth of Salmonella Typhimurium and Escherichia coli, artificially inoculated on mature digestate, were also conducted under both anaerobic and aerobic conditions with the aim to assess the effectiveness of mature digestate as microbial growth medium. Concentrations of Salmonella Typhimurium and Escherichia coli were drastically reduced after a short time of incubation under anaerobic process and the two microorganisms already resulted undetectable after 24-48 h, whereas, under aerobic conditions, two microorganisms' concentrations were stably high for longer than 10 days. The combination of no free oxygen, high temperature, anaerobic metabolites (e.g. total ammonium nitrogen, and volatile fatty acids) production, bacteria competition and lack of nutritional elements in mature digestate considerably reduced in 24-48 h the sanitary risks associated to accidently contaminated digestate. Furthermore, a SARS-CoV-2 monitoring survey on mature digestate during 13 months, resulted in the absence of the virus RNA in the analyzed digestate.


Asunto(s)
COVID-19 , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Digestión , Escherichia coli , Humanos , Metano , SARS-CoV-2 , Salmonella typhimurium/genética
9.
Sci Total Environ ; 796: 148905, 2021 Nov 20.
Artículo en Inglés | MEDLINE | ID: covidwho-1401844

RESUMEN

Several treatment plants were sampled for influent, primary clarifier sludge, return activated sludge (RAS), and anaerobically digested sludge throughout nine weeks during the summer of the COVID-19 pandemic. Primary clarifier sludge had a significantly higher number of SARS-CoV-2 gene copy number per liter (GC/L) than other sludge samples, within a range from 1.0 × 105 to 1.0 × 106 GC/L. Gene copy numbers in raw influent significantly correlated with gene copy numbers in RAS in Silver Creek (p-value = 0.007, R2 = 0.681) and East Canyon (p-value = 0.009, R2 = 0.775) WRFs; both of which lack primary clarifiers or industrial pretreatment processes. This data indicates that SARS-CoV-2 gene copies tend to partition into primary clarifier sludges, at which point a significant portion of them are removed through sedimentation. Furthermore, it was found that East Canyon WRF gene copy numbers in influent were a significant predictor of daily cases (p-value = 0.0322, R2 = 0.561), and gene copy numbers in RAS were a significant predictor of weekly cases (p-value = 0.0597, R2 = 0.449). However, gene copy numbers found in primary sludge samples from other plants significantly predicted the number of COVID-19 cases for the following week (t = 2.279) and the week after that (t = 2.122) respectively. These data indicate that SARS-CoV-2 extracted from WRF biosolids may better suit epidemiological monitoring that exhibits a time lag. It also supports the observation that primary sludge removes a significant portion of SARS-CoV-2 marker genes. In its absence, RAS can also be used to predict the number of COVID-19 cases due to direct flow through from influent. This research represents the first of its kind to thoroughly examine SARS-CoV-2 gene copy numbers in biosolids throughout the wastewater treatment process and the relationship between primary, return activated, and anaerobically digested sludge and reported positive COVID-19 cases.


Asunto(s)
COVID-19 , Purificación del Agua , Anaerobiosis , Humanos , Pandemias , Prevalencia , SARS-CoV-2 , Aguas Residuales , Agua
10.
Environ Res ; 201: 111488, 2021 10.
Artículo en Inglés | MEDLINE | ID: covidwho-1275304

RESUMEN

Waste activated sludge (WAS) and animal manure are two significant reservoirs of glucocorticoids (GCs) in the environment. However, GC degradation during anaerobic digestion (AD) of WAS or animal manure has rarely been investigated. In this study, co-fermentation of WAS and animal manure was conducted to investigate the performance of AD in controlling GC dissemination. Effects of manure type on GC degradation and sludge acidification were investigated. The results showed that co-fermentation of WAS and chicken manure (CM) significantly enhanced the degradation of hydrocortisone (HC) to 99%, betamethasone (BT) to 99%, fluocinolone acetonide (FA) to 98%, and clobetasol propionate (CP) to 82% in 5 days with a mixing ratio of 1:1 (g TS sludge/g dw manure) at 55 °C and initial pH of 7. Simultaneously, sludge reduction was increased by 30% and value-added volatile fatty acid (VFA) production was improved by 40%. Even a high GC content of biomass (3.6 mg/g TS) did not impact both sludge hydrolysis and acidification. The amendment of WAS with CM increased soluble organic carbon, Ca2+, and relative abundance of anaerobes (Eubacterium) associated with organic compound degradation. Furthermore, 44 transformation products of HC, BT, FA, and CP with lower lipophilicity and toxicity were identified, indicating possible degradation pathways including hydroxylation, ketonization, ring cleavage, defluorination, hydrogenation, methylation, and de-esterification. Overall, this study provides a practical way to control GC pollution and simultaneously promote waste reduction and VFA production. Animal manure type as an overlooked factor for influencing co-fermentation performance and pollutant degradation was also highlighted.


Asunto(s)
COVID-19 , Aguas del Alcantarillado , Anaerobiosis , Animales , Reactores Biológicos , Ácidos Grasos Volátiles , Fermentación , Glucocorticoides , Humanos , Concentración de Iones de Hidrógeno , Estiércol , SARS-CoV-2
11.
Acta Diabetol ; 58(10): 1329-1341, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: covidwho-1245645

RESUMEN

INTRODUCTION: Obesity is a condition that generally limits work capacity and predisposes to a number of comorbidities and related diseases, the last being COVID-19 and its complications and sequelae. Physical exercise, together with diet, is a milestone in its management and rehabilitation, although there is still a debate on intensity and duration of training. Anaerobic threshold (AT) is a broad term often used either as ventilatory threshold or as lactate threshold, respectively, detected by respiratory ventilation and/or respiratory gases (VCO2 and VO2), and by blood lactic acid. AIMS AND METHODOLOGY: This review outlines the role of AT and of the different variations of growth hormone and catecholamine, in subjects with obesity vs normal weight individuals below and beyond AT, during a progressive increase in exercise training. We present a re-evaluation of the effects of physical activity on body mass and metabolism of individuals with obesity in light of potential benefits and pitfalls during COVID-19 pandemic. Comparison of a training program at moderate-intensity exercise (< AT) with training performed at moderate intensity (< AT) plus a final bout of high-intensity (> AT) exercise at the end of the aerobic session will be discussed. RESULTS: Based on our data and considerations, a tailored strategy for individuals with obesity concerning the most appropriate intensity of training in the context of rehabilitation is proposed, with special regard to potential benefits of work program above AT. CONCLUSION: Adding bouts of exercise above AT may improve lactic acid and H+ disposal and improve growth hormone. Long-term aerobic exercise may improve leptin reduction. In this way, the propensity of subjects with obesity to encounter a serious prognosis of COVID-19 may be counteracted and the systemic and cardiorespiratory sequelae that may ensue after COVID-19, can be overcome. Individuals with serious comorbidities associated with obesity should avoid excessive exercise intensity.


Asunto(s)
Umbral Anaerobio , Anaerobiosis , COVID-19 , Pandemias , Ejercicio Físico , Humanos , Obesidad/epidemiología , Obesidad/terapia , SARS-CoV-2
12.
Med Hypotheses ; 148: 110520, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: covidwho-1051862

RESUMEN

Following the decline in Physical Activity (PA) due to COVID-19 restrictions in the form of government mandated lockdowns and closures of public spaces, the modulatory effect of physical exercise on immunity is being heavily revisited. In an attempt to comprehend the wide discrepancy in patient response to COVID-19 and the factors that potentially modulate it, we summarize the findings relating PA to inflammation and immunity. A distinction is drawn between moderate intensity and high intensity physical exercise based on the high lactate production observed in the latter. We hypothesize that, the lactate production associated with high intensity anaerobic exercise is implicated in the modulation of several components of the innate and adaptive immunity. In this review, we also summarize these immunomodulatory effects of lactate. These include increasing serum IL-6 levels, the main mediator of cytokine storms, as well as affecting NK cells, Macrophages, Dendritic cells and cytotoxic T-lymphocytes. The implications of high lactate levels in athletic performance are highlighted where athletes should undergo endurance training to increase VO2 max and minimize lactate production. Tumor models of hypoxia were also reported where lactate levels are elevated leading to increased invasiveness and angiogenesis. Accordingly, the novel lactate blocking strategy employed in cancer treatment is evaluated for its potential benefit in COVID-19 in addition to the readily available beta-blockers as an antagonist to lactate. Finally, we suggest the diagnostic/prognostic purpose of the elevated lactate levels that can be determined through sweat lactate testing. It is the detrimental effect of lactate on immunity and its presence in sweat that qualify it to be used as a potential non-invasive marker of poor COVID-19 outcome.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Ácido Láctico/antagonistas & inhibidores , Anaerobiosis/inmunología , COVID-19/inmunología , COVID-19/fisiopatología , Ejercicio Físico/fisiología , Humanos , Inflamación/inmunología , Interleucina-6/sangre , Ácido Láctico/inmunología , Ácido Láctico/metabolismo , Modelos Inmunológicos , Pandemias , SARS-CoV-2
13.
Sci Total Environ ; 760: 144309, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: covidwho-968050

RESUMEN

Human enteric pathogens are a major global concern, as they are responsible for thousands of preventable deaths every year. New pathogens in wastewater are constantly emerging. For example, SARS-CoV-2 has been recently detected in domestic sewage and primary sludge. Knowledge about the reduction of viruses in wastewater treatment and their partitioning between the treated liquid effluent versus the sludge or biosolids is still very scarce, especially in countries with emerging economies and tropical climates. Upflow anaerobic sludge blanket (UASB) reactors are among the top three most commonly used technologies for the treatment of sewage in Latin America and the Caribbean, and their use has become increasingly common in many other low- and middle-income countries. High-rate algal ponds (HRAP) are regarded as a sustainable technology for the post-treatment of UASB effluent. This study evaluated the overall reduction and the liquid-solid partitioning of somatic coliphages, F-specific coliphages, and E. coli in a pilot-scale system comprised of a UASB reactor followed by HRAPs treating real wastewater. Average log removal for somatic and F-specific coliphages were 0.40 and 0.56 for the UASB reactor, and 1.15 and 1.70 for HRAPs, respectively. The overall removal of both phages in the system was 2.06-log. Removal of E. coli was consistently higher. The number of viruses leaving the system in the UASB solids and algal biomass was less than 10% of the number leaving in the clarified liquid effluent. The number of E. coli leaving the system in solids residuals was estimated to be approximately one order of magnitude higher than the number of E. coli leaving in the liquid effluent. Results from this study demonstrate the suitability of UASB-HRAP systems to reduce viral and bacterial indicators from domestic sewage and the importance of adequately treating sludge for pathogen reduction before they are used as biosolids.


Asunto(s)
COVID-19 , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Región del Caribe , Escherichia coli , Humanos , Estanques , SARS-CoV-2 , Eliminación de Residuos Líquidos
14.
Sci Total Environ ; 754: 142329, 2021 Feb 01.
Artículo en Inglés | MEDLINE | ID: covidwho-759345

RESUMEN

For the first time, we present, i) an account of decay in the genetic material loading of SARS-CoV-2 during Upflow Anaerobic Sludge Blanket (UASB) treatment of wastewater, and ii) comparative evaluation of polyethylene glycol (PEG), and ultrafiltration as virus concentration methods from wastewater for the quantification of SARS-CoV-2 genes. The objectives were achieved through tracking of SARS-CoV-2 genetic loadings i.e. ORF1ab, N and S protein genes on 8th and 27th May 2020 along the wastewater treatment plant (106000 m3 million liters per day) equipped with UASB system in Ahmedabad, India. PEG method performed better in removing materials inhibiting RT-qPCR for SARS-CoV-2 gene detection from the samples, as evident from constant and lower CT values of control (MS2). Using the PEG method, we found a reduction >1.3 log10 reduction in SARS-CoV-2 RNA abundance during UASB treatment, and the RNA was not detected at all in the final effluent. The study implies that i) conventional wastewater treatment systems is effective in SARS-CoV-2 RNA removal, and ii) UASB system significantly reduces SARS-CoV-2 genetic loadings. Finally, PEG method is recommended for better sensitivity and inhibition removal during SARS-CoV-2 RNA quantification in wastewater.


Asunto(s)
COVID-19 , Aguas del Alcantarillado , Aguas Residuales , Anaerobiosis , Reactores Biológicos , Humanos , India , Pandemias , ARN , Eliminación de Residuos Líquidos
15.
Med Hypotheses ; 144: 110002, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: covidwho-610333

RESUMEN

Straying away from a sedentary lifestyle is essential, especially in these troubled times of a global pandemic to reverse the ill effects associated with the health risks as mentioned earlier. In the view of anticipated effects on immune system and prevention against influenza and Covid-19, globally moderate to vigorous exercises are advocated wearing protective equipment such as facemasks. Though WHO supports facemasks only for Covid-19 patients, healthy "social exercisers" too exercise strenuously with customized facemasks or N95 which hypothesized to pose more significant health risks and tax various physiological systems especially pulmonary, circulatory and immune systems. Exercising with facemasks may reduce available Oxygen and increase air trapping preventing substantial carbon dioxide exchange. The hypercapnic hypoxia may potentially increase acidic environment, cardiac overload, anaerobic metabolism and renal overload, which may substantially aggravate the underlying pathology of established chronic diseases. Further contrary to the earlier thought, no evidence exists to claim the facemasks during exercise offer additional protection from the droplet transfer of the virus. Hence, we recommend social distancing is better than facemasks during exercise and optimal utilization rather than exploitation of facemasks during exercise.


Asunto(s)
COVID-19/prevención & control , Ejercicio Físico , Hipercapnia/etiología , Hipoxia/etiología , Máscaras/efectos adversos , Ventilación Pulmonar , Microbiología del Aire , Anaerobiosis , Encéfalo/fisiopatología , COVID-19/inmunología , COVID-19/transmisión , Dióxido de Carbono/sangre , Ejercicio Físico/fisiología , Guías como Asunto , Corazón/fisiopatología , Humanos , Hipercapnia/sangre , Hipercapnia/inmunología , Hipercapnia/fisiopatología , Hipoxia/sangre , Hipoxia/inmunología , Hipoxia/fisiopatología , Riñón/fisiopatología , Músculo Esquelético/fisiopatología , Oxígeno/sangre , Consumo de Oxígeno , SARS-CoV-2/aislamiento & purificación , Organización Mundial de la Salud
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA