High Species C Human Adenovirus Genome Copy Numbers in the Treated Water Supply of a Neotropical Area of the Central-West Region of Brazil

Occurrence of human pathogenic viruses in drinking water and in its sources: A review

Since many waterborne diseases are caused by human pathogenic viruses, virus monitoring of drinking water (DW) and DW sources is crucial for public health. Therefore, the aim of this review was to describe the occurrence of human pathogenic viruses in DW and DW sources; the occurrence of two viruses proposed as novel indicators of human faecal contamination (Pepper mild mottle virus and Tobacco mosaic virus) was also reported. This research was focused on articles that assessed viral occurrence using molecular methods in the surface water used for DW production (SW-D), groundwater used for DW production (GW-D), DW and bottled-DW (BW). A total of 1544 studies published in the last 10 years were analysed, and 79 were ultimately included. In considering the detection methods, filtration is the most common concentration technique, while quantitative polymerase chain reaction is the most common quantification technique. Regarding virus occurrence in SW-D, GW-D, and DW, high percentages of positive samples were reported for adenovirus, polyomavirus and Pepper mild mottle virus. Viral genomes were frequently detected in SW-D and rarely in GW-D, suggesting that GW-D may be a safe DW source. Viral genomes were also detected in DW, posing a possible threat to human health. The lowest percentages of positive samples were found in Europe, while the highest were found in Asia and South America. Only three articles assessed viral occurrence in BW. This review highlights the lack of method standardization and the need for legislation updates.

Escherichia coli, Species C Human Adenovirus, and Enterovirus in Water Samples Consumed in Rural Areas of Goiás, Brazil

Rural environments lack basic sanitation services. Facilities for obtaining water and disposing sewage are often under the initiative of each resident, who may not be able to build and maintain them properly. Thus, water for human consumption is subject to fecal contamination and, consequently, the presence of waterborne pathogens, such as enteric viruses. This study evaluated fecal contamination of water samples from individual sources used for domestic water supply on small farms in the state of Goiás, Brazil. Samples were collected from 78 houses whose water sources were tubular wells, dug wells, springs, and surface waters. Escherichia coli (EC) bacteria, analyzed by the defined chromogenic substrate method, was used as a traditional indicator of fecal contamination. The enteric viruses Human mastadenovirus (HAdV) and Enterovirus (EV), analyzed by qPCR, were tested as complementary indicators of fecal contamination. At least one of these markers was found in 89.7% of the samples. Detection rates were 79.5% for EC, 52.6% for HAdV, and 5.1% for EV. The average concentration for EC was 8.82 × 10¹ most probable number (MPN) per 100 mL, while for HAdV and EV the concentrations were 7.51 × 10⁵ and 1.89 × 10⁶ genomic copies (GC) per liter, respectively. EC was the most frequent marker in ground and surface water samples. HAdV was detected significantly more frequently in groundwater than in surface water and was more efficient in indicating contamination in tubular wells. There was no association of frequencies or correlation of concentrations between EC and HAdV. HAdV indicated human fecal contamination and performed well as a complementary indicator. The results reveal that a large part of the analyzed population is vulnerable to waterborne diseases caused by enteric pathogens.

Enteric viruses and adenovirus diversity in waters from 2016 Olympic venues

Rio de Janeiro's inner and coastal waters are heavily impacted by human sewage pollution for decades. Enteric viruses, including human adenoviruses (HAdV), human enterovirus (EV), group A rotavirus (RV) and hepatitis A virus (HAV) are more likely to be found in contaminated surface waters. The present work aimed to assess the frequency and loads of EV, HAdV-C and -F species, RV and HAV in sand and water samples from venues used during the 2016 Summer Olympics and by tourists attending the event. Sixteen monthly collections were carried out from March 2015 to July 2016 in 12 different sites from Rio de Janeiro, Brazil. Total and thermotolerant coliform counting was performed along molecular detection of virus was performed using quantitative polymerase chain reaction (qPCR). Analyses of all samples were further investigated by integrated cell culture PCR to check about the presence of HAdV infectious virus particles. The results show that 95.9% of water samples showed contamination with at least one type of virus. Regarding the viruses individually (% for water and sand respectively): HAdV-C (93.1%-57.8%), HAdV-F (25.3%-0%), RV (12.3%-4.4%), EV (26.7%-8.8%) and HAV (0%). The viral loads ranged from 10³gc/L up to 10⁹gc/L (water), and 10³gc/g to 10⁶gc/g (sand). In the phylogenetic tree, were classified into four main clusters, referring to species C, D, F and BAdV. And up to 90% of sites studied presented at least once presence of infectious HAdV-C. The most contaminated points were the Rodrigo de Freitas Lagoon, where Olympic rowing took place, and the Marina da Glória, the starting point for the sailing races, demonstrating serious problem of fecal contamination of water resources and threatens the health of Olympic athletes, tourists and residents.