Prevalence and genetic diversity of waterborne pathogenic viruses in surface waters of tropical urban catchments

Abstract

Aims: To study the virological quality of surface water from highly urbanized tropical water catchment areas and to determine predominant enteric viral genotypes in surface water. Methods and Results: A wide range of human pathogenic viruses in urban surface waters was screened by nested PCR assays after concentration by ultrafiltration. Among the 84 water samples collected, at least one virus was detected in 70 (83·3%) of these samples. Noroviruses were determined to be the most prevalent enteric viruses detected in urban surface water samples, followed by astroviruses, enteroviruses, adenoviruses and hepatitis A viruses. The molecular characterization of environmental viral isolates suggested co‐circulation of multiple genotypes of both noroviruses GI and GII, astroviruses and enteroviruses in urban surface waters. Conclusions: Human enteric viruses with great genetic diversity were detected in surface waters, indicating the presence of human origin of faecal contamination in highly urbanized water catchment areas. Significance and Impact of the Study: The present study identifies and characterizes potential viral hazards of source waters for drinking water supply and recreational activities. This will enable scientific decisions to be made regarding the selection and prioritization of human pathogenic viruses to be included in the future risk assessment and treatment evaluation for water and wastewater.

Wastewater Analysis Indicates that Genetically Diverse Astroviruses, Including Strains Belonging to Novel Clades MLB and VA, Are Circulating within Japanese Populations

“…2 and Table 2). Classic HAstV-1 has been the type that has been the most frequently found in clinical samples worldwide (10,44,45), as well as in urban wastewater and surface water samples (9,46). In the present study, however, classic HAstV-1 was detected in only 2 influent samples, while classic HAstV-2 and classic HAstV-4/8 were more frequently detected in both influent and effluent samples.…”

“…HAstVs are antigenically or genetically classified into eight different types (HAstV type 1 [HAstV-1] to HAstV-8). Previous studies revealed that HAstV-1 is the most prevalent type among infected individuals and in the environment, followed by 5,[9][10][11][12][13].Because HAstV can be excreted in the feces of infected individuals at a high concentration (up to 10 15 particles/g) (14), examination of municipal wastewater samples could be an effective approach to understand the actual prevalence and epidemiology of these viruses (15, 16). In spite of their importance as enteric pathogens, the occurrence and other characteristics of HAstVs in water compared to those of other enteric viruses, such as noroviruses, rotaviruses, and adenoviruses, have not been well documented (17, 18).…”

“…HAstVs are antigenically or genetically classified into eight different types (HAstV type 1 [HAstV-1] to HAstV-8). Previous studies revealed that HAstV-1 is the most prevalent type among infected individuals and in the environment, followed by 5,[9][10][11][12][13].…”

Environmental Assessment of Classical Human Astrovirus in Uruguay

“…HAstV, like others enteric viruses, are frequently detected in sewage and other environmental water samples mainly as a result of an inadequate discharge of the urban sewage in natural course of waters (Pintó et al 2001;Le Cann et al 2004;Aw and Gin 2011) however, only scarce studies worldwide, have performed a molecular characterization of them in sewage (Meleg et al 2006;Rodríguez-Díaz et al 2009;Aw and Gin 2010).…”

Hepatitis A Virus (HAV)

“…However, several of the samples did contain human adenoviruses, supporting the possibility that water was the source of the infection. Aw and Gin (2011) analyzed 45 surface water samples in an urban area of Singapore and detected HAV RNA in only four of them (8.9%). While samples from both an urban river and canal were analyzed, the only positive samples were from the canals (4/15 positive).…”