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This study assessed the sources of contamination of water matrices in a rural area using detection of a host-specific virus (human adenovirus [HAdV], porcine adenovirus [PAdV] and bovine polyomaviruses [BoPyV]) as potential microbial source-tracking tool, and rotavirus A [RVA], given its epidemiological importance in Brazil. From July 2017 to June 2018, 92 samples were collected from eight points (P1-P8) of surface and raw waters in southeastern region of Brazil. Fifty-five (59.8%) were positive for HAdV, 41 (44.5%) for RVA, 10 (10.9%) for PAdV and four (4.3%) for BoPyV. HAdV and RVA were detected at all sites, and over the entire sampling period, PAdV was detected at a porcine breeding area and at Guarda River site, presenting high concentrations up to 2.6 × 10 9 genome copies per liter [GC/L], and viral concentrations ranging from 9.6 × 10 1 to 7.1 × 10 7 , while BoPyV (1.5 × 10 4 GC/L-9.2 × 10 5 GC/L) was only detected in samples from the bovine breeding areas. The combination of human and animal virus circulation presents a potential impact in the environment due to raw sewage discharge from regional communities, as well as potential hazard to human and animal health., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Viral bivalve contamination is a recognized food safety hazard. Therefore, this study investigated the detection rates, seasonality, quantification, and genetic diversity of enteric viruses in bivalve samples (mussels and oysters). We collected 97 shellfish samples between March 2018 and February 2020. The screening of samples by qPCR or RT-qPCR revealed the detection of norovirus (42.3%), rotavirus A (RVA; 16.5%), human adenovirus (HAdV; 24.7%), and human bocavirus (HBoV; 13.4%). There was no detection of hepatitis A virus. In total, 58.8% of shellfish samples tested positive for one or more viruses, with 42.1% of positive samples contaminated with two or more viruses. Norovirus showed the highest median viral load (3.3 × 10 6 GC/g), followed by HAdV (median of 3.5 × 10 4 GC/g), RVA (median of 1.5 × 10 3 GC/g), and HBoV (median of 1.3 × 10 3 GC/g). Phylogenetic analysis revealed that norovirus strains belonged to genotype GII.12[P16], RVA to genotype I2, HAdV to types -C2, -C5, and -F40, and HBoV to genotypes -1 and -2. Our results demonstrate the viral contamination of bivalves, emphasizing the need for virological monitoring programs to ensure the quality and safety of shellfish for human consumption and as a valuable surveillance tool to monitor emerging viruses and novel variants.

Human adenovirus (HAdV) types F40/41 have long been recognized as major viral agents of acute gastroenteritis (AGE) in children. Despite this, studies on HAdV molecular epidemiology are sparse, and their real impact is likely under-estimated. Thus, our goal was to investigate HAdV incidence, enteric and non-enteric types circulation, co-detections with rotavirus and norovirus and DNA shedding in stool samples from inpatients and outpatients from eleven Brazilian states. During the three-year study, 1012 AGE stool samples were analysed by TaqMan-based qPCR, to detect and quantify HAdV. Positive samples were genotyped by partial sequencing of the hexon gene followed by phylogenetic analysis. Co-detections were accessed by screening for rotavirus and norovirus. Overall, we detected HAdV in 24.5% of single-detected samples (n = 248), with a prevalence of type F41 (35.8%). We observed a higher incidence in children between 6 to 24 months, without marked seasonality. Additionally, we observed a statistically higher median viral load among single-detections between enteric and non-enteric types and a significantly lower HAdV viral load compared to rotavirus and norovirus in co-detections (p < 0.0001). Our study contributes to the knowledge of HAdV epidemiology and reinforces the need for the inclusion of enteric types F40/41 in molecular surveillance programs., (© 2022. The Author(s).)

Roof-harvested rainwater (RHRW) is considered relatively clean water, even though the possible presence of pathogens in the water may pose human health risks. In this study, we investigated the occurrence of enteric viruses in the first flush (10 mm) of RHRW from a densely populated and low-income urbanized region of Rio de Janeiro. One hundred samples (5 L) were collected from 10 rainfall events between April 2015 and March 2017. RNA and DNA viruses were concentrated using the skimmed milk flocculation method and analyzed using the TaqMan® quantitative RT-qPCR and qPCR. Human adenoviruses, noroviruses, rotaviruses A, and avian parvoviruses were detected in 54%, 31%, 12%, and 12% of the positive samples. JC polyomavirus, also targeted, was not detected. Virus concentrations ranged from 1.09 × 10 1 to 2.58 × 10 3 genome copies/Liter (GC/L). Partial nucleotide sequence confirmed the presence of HAdV type 41, norovirus genotype GII.4, and avian parvovirus 1. The results suggest that the first flush diversion devices may not adequately remove enteric virus from the rainwater. Additional treatment of RHRW is required to mitigate potential health risks from potable use of captured water., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents of waterborne diseases and have been described as important markers of human faecal contamination. This study aimed to investigate viruses' presence as an indicator of drinking water quality in low-income communities in the Manguinhos area, Rio de Janeiro, Brazil. Three hundred and four drinking water samples (2L/each) were collected along the drinking water distribution-to-consumption pathway in households, as well as healthcare and school units. Water samples were collected both directly from the water supply prior to distribution and after storage in tanks and filtration units. Using qPCR, viruses were detected 50 times in 45 water samples (15%), 19 of these being human adenovirus, 17 rotavirus A and 14 norovirus GII. Viral loads recovered ranged from 5E+10 to 8.7E+10 6 genome copies/Liter. Co-detection was observed in five household water samples and there was no difference regarding virus detection across sampling sites. Precarious and inadequate environmental conditions characterized by the lack of local infrastructure regarding basic sanitation and waste collection in the territory, as well as negligent hygiene habits, could explain viral detection in drinking water in regions with a water supply system.

Sewage treatment may be insufficient for the complete removal of enteric viruses, such as human adenoviruses (HAdV) and group A rotavirus (RVA). The differences in the efficiency of the treatment methodologies used may interfere with the detection of these viruses. The objective of this study was to optimize a skimmed-milk flocculation technique for the recovery of HAdV and RVA in the samples of treated effluent. The treated effluent collected at the wastewater treatment plant (WWTP) was processed via four protocols including modifications in the initial centrifugation step and the final concentration of skimmed-milk. The viral load and recovery rate were determined by quantitative PCR TaqMan® System. The highest recovery rates of HAdV, RVA, and bacteriophage PP7 (internal control process) were obtained when the concentration of skimmed-milk was doubled and no centrifugation step was used for the sample clarification. The optimized protocol was assessed in a field study conducted with 24 treated effluent samples collected bi-monthly during 2015. HAdV and RVA were detected in 50.0% (12/24) and 33.3% (08/24) of the samples tested, respectively, throughout the year, without seasonal variation (p > 0.05). This study corroborates the use of the organic flocculation method for virus recovery in environmental samples with the adaptation of the protocols to different aquatic matrices.

Return of treated sludge to the environment poses concerns and has stimulated the development of studies on viral monitoring in this matrix, in order to assess its potential risks for public health. Human adenovirus (HAdV) has been identified as a putative viral marker of faecal contamination due to its stability and resistance to the sewage treatment process. The aim of this study was to optimize the organic flocculation procedure in order to establish an appropriate methodology for HAdV recovery from sewage sludge samples. Four protocols (A-D) have been proposed, with changes in the initial sample dilution, in the stirring time and in the final concentration of skimmed-milk. A single sludge sample was obtained in Wastewater Treatment Plant (WWTP) and divided into aliquots. In each protocol, three aliquots were inoculated with HAdV and bacteriophage PP7 and a non-inoculated one was used as negative control. Viral load and recovery rate were determined by quantitative PCR. HAdV recovery rate varied between the protocols tested (p=0.016) and the best result was obtained through the protocol C. In order to confirm this result a field study with activated, thickened and digested sludge samples was carried out. Different types of sludge were obtained in two WWTPs and processed using protocol C. HAdV was detected in all samples, with a similar or higher viral load than those obtained with other concentration techniques already applied to sludge. Protocol C proved to be really efficient, with the advantage of showing low cost and practicability in routine laboratories., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Rotavirus A and human adenovirus dissemination were demonstrated both in a pediatric ward and in a neonatal intensive care unit (NICU) of the same pediatric hospital. Virus detection from fomites samples were higher in the pediatric ward (42.3% [137 out of 324]) than in the NICU (4.5% [7 out of 156]), revealing that cleaning processes used in our NICU are effective in reducing viral contamination, suggesting human adenovirus as a potential biomarker of contamination of hospital fomites., (Copyright © 2016 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.)

Aims: This study was conducted to assess rotavirus A (RV-A), genogroup II (GII) norovirus (NoV), and human adenovirus (HAdV) dissemination in recreational water in an urban beach located in the city of Rio de Janeiro and their persistence during rainfall events., Methods and Results: Viruses, including bacteriophage (PP7), used as internal control, were concentrated, reverse transcribed and quantified by a low-cost method based on organic flocculation with skimmed milk coupled with quantitative polymerase chain reaction protocols. The analysis of 74 superficial water samples obtained during 6 months of monitoring detected HAdV (66%), RV-A (37%) and GII NoV (14%), with a mean viral load of 4·1 log10 genome copies l(-1) (g.c. l(-1) ), 4·3 log10 g.c l(-1) and 3·8 log10 g.c. l(-1) , respectively. Investigation of those viruses during two rainfall events showed a longer permanence after rainfall events compared with bacterial indicators., Conclusions: The results highlight the need for further monitoring using viral parameters to determine the microbiological quality of recreational waters to allow bath in these waters, especially during rainy events., Significance and Impact of the Study: This study provides data on virus contamination in recreational waters on tourist beaches frequented throughout the year, emphasizing the importance of viral parameters for assessing microbiological quality of water, as well as the potential risk of waterborne infections., (© 2014 The Society for Applied Microbiology.)