Detection Of Enteric Viruses Research Articles

SIV Infection-Mediated Changes in Gastrointestinal Bacterial Microbiome and Virome Are Associated with Immunodeficiency and Prevented by Vaccination.

AIDS caused by simian immunodeficiency virus (SIV) infection is associated with gastrointestinal disease, systemic immune activation, and, in cross-sectional studies, changes in the enteric virome. Here we performed a longitudinal study of a vaccine cohort to define the natural history of changes in the fecal metagenome in SIV-infected monkeys. Matched rhesus macaques were either uninfected or intrarectally challenged with SIV, with a subset receiving the Ad26 vaccine, an adenovirus vector expressing the viral Env/Gag/Pol antigens. Progression of SIV infection to AIDS was associated with increased detection of potentially pathogenic viruses and bacterial enteropathogens. Specifically, adenoviruses were associated with an increased incidence of gastrointestinal disease and AIDS-related mortality. Viral and bacterial enteropathogens were largely absent from animals protected by the vaccine. These data suggest that the SIV-associated gastrointestinal disease is associated with the presence of both viral and bacterial enteropathogens and that protection against SIV infection by vaccination prevents enteropathogen emergence.

A Novel High-Throughput Method for Molecular Detection of Human Pathogenic Viruses Using a Nanofluidic Real-Time PCR System.

Human enteric viruses are recognized as the main causes of food- and waterborne diseases worldwide. Sensitive and quantitative detection of human enteric viruses is typically achieved through quantitative RT-PCR (RT-qPCR). A nanofluidic real-time PCR system was used to develop novel high-throughput methods for qualitative molecular detection (RT-qPCR array) and quantification of human pathogenic viruses by digital RT-PCR (RT-dPCR). The performance of high-throughput PCR methods was investigated for detecting 19 human pathogenic viruses and two main process controls used in food virology. The conventional real-time PCR system was compared to the RT-dPCR and RT-qPCR array. Based on the number of genome copies calculated by spectrophotometry, sensitivity was found to be slightly better with RT-qPCR than with RT-dPCR for 14 viruses by a factor range of from 0.3 to 1.6 log10. Conversely, sensitivity was better with RT-dPCR than with RT-qPCR for seven viruses by a factor range of from 0.10 to 1.40 log10. Interestingly, the number of genome copies determined by RT-dPCR was always from 1 to 2 log10 lower than the expected copy number calculated by RT-qPCR standard curve. The sensitivity of the RT-qPCR and RT-qPCR array assays was found to be similar for two viruses, and better with RT-qPCR than with RT-qPCR array for eighteen viruses by a factor range of from 0.7 to 3.0 log10. Conversely, sensitivity was only 0.30 log10 better with the RT-qPCR array than with conventional RT-qPCR assays for norovirus GIV detection. Finally, the RT-qPCR array and RT-dPCR assays were successfully used together to screen clinical samples and quantify pathogenic viruses. Additionally, this method made it possible to identify co-infection in clinical samples. In conclusion, given the rapidity and potential for large numbers of viral targets, this nanofluidic RT-qPCR assay should have a major impact on human pathogenic virus surveillance and outbreak investigations and is likely to be of benefit to public health.

Detection and molecular characterization of enteric viruses in enteritis-affected commercial broiler chickens in India

A study was conducted to detect and characterize the enteric viruses (chicken astrovirus, avian nephritis virus and avian orthoreovirus) present in flocks of commercial broiler chickens suffering from enteritis in Haryana, India. The intestinal contents were collected from 65 enteritis-affected flocks (cases) and tested by reverse transcription PCR (RT-PCR). Of these 65 cases, 35 (53.80%) were positive for a single virus and 26 (40.00%) for two viruses. The remaining four samples were negative for all three viruses tested. Of the 65 cases, 57 were positive for chicken astrovirus (CAstV) while 30 cases had avian nephritis virus (ANV). None of the cases were positive for orthoreovirus. Comparison of 12 CAstVs of this study with previously published CAstV sequences revealed nucleotide identities ranging from 73.20 to 98.00%. The nucleotide identities ranged between 83.10-95.50% when nine ANVs of this study were compared with previously reported ANV sequences. The amino acid sequences of CAstVs in comparison to previously published sequences revealed certain unique changes. Phylogeny based on polymerase gene revealed that CAstVs and ANVs of this study were under the same monophyletic clade. In conclusion, a large number of broiler chicken flocks experiencing enteritis were positive for CAstV and ANV by RT-PCR. The presence of more than one enteric virus in enteritis-affected flocks and changes at the genetic level in these viruses may affect the severity of disease.

A 1-Year Study on the Detection of Human Enteric Viruses in New Caledonia.

Human enteric viruses occur in high concentrations in wastewater and can contaminate receiving environmental waters. Due to the lack of data on the prevalence of enteric viruses in New Caledonia, the presence and the concentrations of enteric viruses in wastewater and seawater were determined. Untreated wastewater and seawater samples were collected monthly for 1 year from a wastewater treatment plant (WWTP) and from the WWTP's outlet, located directly on a popular recreational beach. Samples were tested for norovirus genogroups I and II (NoV GI and GII), astroviruses (AsV), sapoviruses (SaV), enteroviruses (EV), hepatitis A viruses (HAV), rotaviruses (RoV), human adenoviruses (HAdV) and human polyomaviruses (HPyV). To support these data, faecal samples from cases of gastroenteritis were tested for the first time for NoV and detected in the population. NoV GI, NoV GII, EV, SaV, HAdV and HPyV were detected in all wastewaters, RoV in 75% and AsV in 67%. HAV were not detected in wastewater. Overall, 92% of seawater samples were positive for at least one virus. HPyV were detected most frequently in 92% of samples and at concentrations up to 7.7 × 10(3) genome copies/L. NoV GI, NoV GII, EV, SaV, RoV and HAdV were found in 33, 66, 41, 33, 16 and 66% of seawater samples, respectively. AsV were not detected in seawater. This study reports for the first time the presence of NoV and other enteric viruses in New Caledonia and highlights the year-round presence of enteric viruses in the seawater of a popular beach.

A probe-free four-tube real-time PCR assay for simultaneous detection of twelve enteric viruses and bacteria

ObjectivesWe aim to develop a multiplex real-time PCR assay to detect the most common pathogens causing community outbreaks of diarrhea. MethodsFour reaction systems of fluorescence dye-based real-time PCR assay were performed to amplify genes of norovirus, sapovirus, rotavirus, astrovirus, adenovirus, Campylobacter jejuni, Yersinia enterocolitica, Vibrio parahaemolyticus, Salmonella spp., Escherichia coli, and Shigella spp. PCR products of each pathogen were identified by characteristic peaks in melting curves. ResultsThe assay was able to achieve detection limit of 50 copies/reaction for each individual virus target, and 140–500CFU/mL for each individual bacterium target. A total of 122 clinical specimens from hospitalized children with acute diarrhea were used to evaluate the assay. The clinical sensitivity was very similar to that of reference methods. Norovirus genogroup II revealed the highest detectable rate (45/122, 36.9%). Coinfection was found in 28 out of 122 (23%) clinical specimens. ConclusionThis assay proved to be a cost-effective, sensitive and reliable method for simultaneous detection of enteric viruses and bacteria.

A multiplex tandem real-time PCR assay for the detection of enteric viruses

Noroviruses (NoVs) are important enteric pathogens that cause gastroenteritis worldwide. The first documented NoV outbreaks in South Africa (SA) were described in 1993. The current NoV prevalence and circulating genotypes are unknown. SA lacks NoV outbreak reporting systems and therefore the number and impact of NoV infections is underestimated.This study aimed to determine the prevalence and genetic diversity of NoV infections in hospitalised paediatric patients with gastroenteritis in SA during 2008.Stool specimens referred for virological analysis from hospitalised children ≤13 years, with gastroenteritis, were screened for rotavirus, human adenovirus and human astrovirus by enzyme immunoassay and for NoV genogroup I (GI), II (GII) and sapovirus by real-time RT-PCR. NoV strains were genotyped, and variants identified, based on sequence and phylogenetic analyses of the 5′ end or the full length of the capsid gene, respectively.Rotavirus was the most prevalent virus detected in 24.2% (61/252) of specimens, followed by NoV in 14.3% (35/245) and adenovirus, astrovirus and sapovirus in 9.6%, 6.7% and 4% of specimens, respectively. NoVs were only detected in children ≤2 years. The GII NoVs (89%) predominated and eight types were identified with GII.4 (43%) detected most frequently. The emerging 2008 GII.4 variant represented 80% of the GII.4 strains.A diverse range of NoV genotypes were identified in hospitalised children with gastroenteritis. The 2008 GII.4 variant was the most frequently detected strain in the study. This is the first report of NoV GII.4 viruses in SA.

ENTERIC VIRUSES AS CONTAMINANTS AND BIOINDICATORS IN ENVIRONMENTAL SAMPLES: A REVIEW

Gastroenteritis, diarrhea, and other diseases can be caused by enteric viruses transmitted by fecal-oral route. Human adenoviruses (HAdV), rotavirus A and C (RVA), hepatitis A and E virus (HAV and HEV, respectively), human astroviruses (HAstV), human noroviruses (HuNV) and enteroviruses (EV) are, among the enteric viruses, the most frequently detected in environment samples. These viruses are usually introduced into aquatic environments by human, industrial, or agricultural activities and are widely distributed all over the world. They have the common characteristics to be structurally stable and can also absorb to solid particles and biofilms, thereby protecting themselves from inactivating factors. This revision aimed to present and discuss: i) most relevant enteric viruses for human and animal health; ii) enteric viruses as contaminants and bioindicators in environmental samples; iii) molecular and cell culture methods for enteric virus detection; iv) use of enteric viruses for microbial risk assessment. Impacts of enteric viruses on environment and the potential use as bioindicators of the sanitary security, such as presence and infectivity studies were discussed as development of new tools for disinfection, monitoring, risk modeling and management, among other studies. DOI: http://dx.doi.org/10.17525/vrrjournal.v20i2.255

Capillary Electrophoresis-Based Detection for Foodborne Enteroviruses in Vegetable Samples

Foodborne enteroviruses such as norovirus, rotavirus and astrovirus can cause gastroenteritis in children under the age of five and infants. In this paper, a novel and ultrasensitive method, combining reverse transcription polymerase chain reaction (RT-PCR) with capillary electrophoresis laser-induced fluorescence (CE-LIF), is proposed to detect three viruses in vegetable samples. The viruses, including norovirus, rotavirus and astrovirus in vegetables, were eluted using glycine buffer (pH 9.5), and concentrated by 15 % polyethylene glycol 6000 (PEG 6000). The primers, targeting the specific and conservative sequences of nucleic acids of the viruses, were synthesized and used in RT-PCR reaction. The amplification products were labeled with highly sensitive SYBR Gold, then separated by capillary electrophoresis and detected by a laser-induced fluorescence detector within 16 min. The intraday and interday relative standard deviation of migration time for the DNA Marker was in the range of 1.09–1.30 and 1.77–2.60 %, respectively, while the detection limits of the three viruses were as low as 1.33 × 102 copies mL−1 for norovirus, 1.86 × 102 copies mL−1 for rotavirus, and 1.40 × 102 copies mL−1 for astrovirus. Meanwhile, the results of homology analysis and specificity experiments showed that the method had good specificity. A fried pickled mustard tuber tested positive for norovirus by the proposed method in an outbreak which happened recently in Chengdu. This protocol demonstrated the possibility for rapid, sensitive and specific detection of foodborne enteric viruses in vegetable samples.

Moving beyond classical markers of water quality: detection of enteric viruses and genotoxicity in water of the Sinos River.

It is well recognized that the classical biological and chemical markers of environmental pollution do not necessarily indicate the presence or absence of emerging threats to public health, such as waterborne viruses and genotoxicants. The purpose of this preliminary study was to evaluate the presence of material of enteroviruses (EV), rotavirus (RV) and adenovirus (AdV) and genotoxicity in water samples from points of routine monitoring of water quality in the main course of the Sinos River. The points are classified into different levels of pollution in accordance to the Brazilian federal regulations. Viral genomes from EV, AdV were detected in two of the 4 collection points regardless of the level of urbanisation of the surrounding areas. In contrast, genotoxicity was not observed in piava (Leporinus obtusidens) fingerlings cultivated on these same water samples. Results were compared with classical physical, chemical and microbiological parameters. There was no clear evidence of association between any of the classical markers and the presence of viral genomes in the water samples tested.

Detection of human enteric viruses in Umgeni River, Durban, South Africa.

The prevalence of adenovirus (AdV), rotaviruses (RV) and enteroviruses (EV) in Umgeni River waters of Durban, South Africa was assessed qualitatively and quantitatively during April 2011 to January 2012 using polymerase chain reaction (PCR)/reverse transcription-polymerase chain reaction (RT-PCR), nested PCR and quantitative PCR (qPCR), as well as nested integrated cell culture PCR (nested ICC-PCR). The phylogenetic analysis of the adenovirus and enterovirus amplicons was also performed. The nested PCR results effectively detected the presence of AdV and EV in all water samples. The results of qPCR demonstrated that higher populations of EV and of AdV were widely found in the Umgeni River. Rotavirus could only be detected in the upper Umgeni River, mainly during drier seasons. Nested ICC-PCR further confirmed the presence of infectious AdV and EV particles in 100% of water samples using various cell lines. The present study identifies potential viral hazards of Umgeni River water for domestic water supply and recreational activities.

A comparative study of digital RT-PCR and RT-qPCR for quantification of Hepatitis A virus and Norovirus in lettuce and water samples

Sensitive and quantitative detection of foodborne enteric viruses is classically achieved by quantitative RT-PCR (RT-qPCR). Recently, digital PCR (dPCR) was described as a novel approach to genome quantification without need for a standard curve. The performance of microfluidic digital RT-PCR (RT-dPCR) was compared to RT-qPCR for detecting the main viruses responsible for foodborne outbreaks (human Noroviruses (NoV) and Hepatitis A virus (HAV)) in spiked lettuce and bottled water. Two process controls (Mengovirus and Murine Norovirus) were used and external amplification controls (EAC) were added to examine inhibition of RT-qPCR and RT-dPCR.For detecting viral RNA and cDNA, the sensitivity of the RT-dPCR assays was either comparable to that of RT-qPCR (RNA of HAV, NoV GI, Mengovirus) or slightly (around 1 log10) decreased (NoV GII and MNV-1 RNA and of HAV, NoV GI, NoV GII cDNA). The number of genomic copies determined by dPCR was always from 0.4 to 1.7 log10 lower than the expected numbers of copies calculated by using the standard qPCR curve. Viral recoveries calculated by RT-dPCR were found to be significantly higher than by RT-qPCR for NoV GI, HAV and Mengovirus in water, and for NoV GII and HAV in lettuce samples. The RT-dPCR assay proved to be more tolerant to inhibitory substances present in lettuce samples. This absolute quantitation approach may be useful to standardize quantification of enteric viruses in bottled water and lettuce samples and may be extended to quantifying other human pathogens in food samples.

Animal and human enteric viruses in water and sediment samples from dairy farms

The detection of enteric viruses accompanied by a characterization of the viruses found in a given environmental matrix may inform about the sources of fecal contamination. In the present work, 55 water samples and 20 sediment samples were collected from 21 small farms in southern Brazil. Coliform counting was done as well as molecular detection of human enterovirus (EV), and human and animal adenoviruses. Viral detection was performed using real-time quantitative PCR (qPCR). Furthermore, the viral viability of human AdV (HAdV) by ICC-RT-qPCR in sediment and water samples was analyzed. Regarding to the coliforms, only 72.7% of the samples showed fecal contamination. HAdV was detected in 87.3% of water samples, followed by AvAdV (27.3%), CAV (20%), BAV (7.3%) and PoAdV or EV (1.8%). From the sediment samples, HAdV (80%) followed by CAV (20%), BAV (5%) and no positive results for PoAdV or EV. The viral loads ranged from 1.57×102gc/L up to 6.68×109gc/L (water), and from 1.97×103gc/g to 2.18×108gc/g (sediment). Most of these viral particles in water should be non-infectious, since after the ICC-PCR, HAdV was detected in only 4 samples (8.8%). On the other hand, it is noticeable that 5 sediment samples (25%) gave positive results for the presence of infectious viral particles.

Affordable Enteric Virus Detection Techniques Are Needed to Support Changing Paradigms in Water Quality Management.

In light of water quality monitoring paradigms shifting to a more holistic approach, it is essential that environmental microbiologists embrace new methodological developments in clinical virology to create rapid, laboratory‐free methods for the identification of wastewater pollution. It is widely accepted that routine monitoring of fecal indicator bacteria (FIB) does not adequately reflect human health risks associated with fecal pollution, especially risks posed by viruses. Enteric viruses are typically more resistant to wastewater treatment and persist longer in the environment than FIB. Furthermore, enteric viruses often have extremely low infectious doses. Currently, the incorporation of sanitary surveys, short‐term monitoring of reference pathogens, exploratory quantitative microbial risk assessments, and predictive ecological models is being championed as the preferred approach to water management. In addition to improved virus concentration methods, simple, point‐of‐use tests for enteric viruses and/or improved viral indicators are needed to complement this emerging paradigm and ensure microbial safety worldwide.

Development of a Luminex assay for the simultaneous detection of human enteric viruses in sewage and river water

Real time PCR (qPCR) is increasingly being used for viral detection in aquatic environments because it enables high specificity and sensitivity of detection. However, the limited number of fluorescent reporter dyes restricts its multiplex application. In this study, a multiplex Luminex assay was established for the simultaneous detection of human adenovirus (HAdV), human polyomavirus (HPyV), enterovirus (EV), rotavirus (RoV), norovirus GI (NoVGI) and norovirus GII (NoVGII). Different river water and wastewater samples were tested for the viruses using both qPCR and the multiplex Luminex xMAP assay. HAdV and HPyV were the most abundant in all environmental samples. HAdV was detected in all river water and wastewater samples, and HPyV was detected in 79% of river water and 95.8% of wastewater samples. The multiplex xMAP assay revealed high specificity and no cross-reactivity. Using the multiplex Luminex assay, the viral detection rates in river water samples were lower than the rates obtained by qPCR for all viruses. Conversely, in wastewater samples, the viral detection rates were the same for both methods. In addition, the analytical sensitivity of the monoplex Luminex assay was comparable to or lower than qPCR. Results suggest that the multiplex Luminex assay could be a reliable method for the simultaneous detection of viral pathogens in wastewater.

Detection and genetic characterization of human enteric viruses in oyster-associated gastroenteritis outbreaks between 2001 and 2012 in Osaka City, Japan

Enteric viruses are an important cause of viral food-borne disease. Shellfish, especially oysters, are well recognized as a source of food-borne diseases, and oyster-associated gastroenteritis outbreaks have on occasion become international occurrences. In this study, 286 fecal specimens from 88 oyster-associated gastroenteritis outbreaks were examined for the presence of 10 human enteric viruses using antigenic or genetic detection methods in order to determine the prevalence of these infections. All virus-positive patients were over 18 years old. The most common enteric virus in outbreaks (96.6%) and fecal specimens (68.9%) was norovirus (NoV), indicating a high prevalence of NoV infection associated with the consumption of raw or under-cooked oysters. Five other enteric viruses, aichiviruses, astroviruses, sapoviruses, enteroviruses (EVs), and rotavirus A, were detected in 30.7% of outbreaks. EV strains were characterized into three rare genotypes, coxsackievirus (CV) A1, A19, and EV76. No reports of CVA19 or EV76 have been made since 1981 in the Infectious Agents Surveillance Report by the National Infectious Diseases Surveillance Center, Japan. Their detection suggested that rare types of EVs are circulating in human populations inconspicuously and one of their transmission modes could be the consumption of contaminated oysters. Rapid identification of pathogens is important for the development of means for control and prevention. The results of the present study will be useful to establish an efficient approach for the identification of viral pathogens in oyster-associated gastroenteritis in adults.

Applicability of Bio‐wipes for the collection of human faecal specimens for detection and characterisation of enteric viruses

To determine whether gastroenteritis viruses and other enteric viruses could be detected in faecal specimens collected with Bio-wipes. Faecal specimens, self-collected with Bio-wipes, from 190 individuals (94 diarrhoeal, 93 non-diarrhoeal, 3 unknown) were screened for eight human enteric viruses (enterovirus, hepatitis A virus, adenovirus, astrovirus, norovirus GI and GII, sapovirus and rotavirus) by real-time (reverse transcription)-polymerase chain reaction. Rotaviruses and noroviruses from positive specimens were genotyped. At least one enteric virus could be detected in 82.6% (157/190) of faecal specimens. Mixed infections of up to four different viruses could be detected in both diarrhoeal and non-diarrhoeal specimens. Enteroviruses were detected most frequently (63.7%), followed by adenoviruses (48.4%) and noroviruses (32.2%). Genotyping was successful for 78.6% of rotaviruses and 44.8% of noroviruses. Bio-wipes provide a user friendly, easier method for stool collection that facilitates enteric virus detection and genetic characterisation.

Enhanced enteric virus detection in sporadic gastroenteritis using a multi-target real-time PCR panel: A one-year study

Viral gastroenteritis causes significant mortality and morbidity worldwide. Identifying the etiology of viral gastroenteritis is a challenge as most enteric viruses (EVs) are non-culturable. This study is to develop an EV testing panel using real-time PCR (EVPrtPCR) to simultaneously detect rotavirus, norovirus, sapovirus, astrovirus, and enteric adenovirus in stool samples. EVPrtPCR using universal amplification conditions was run in a single instrument run. EVPrtPCR was used to test 2,486 sporadic gastroenteritis samples submitted for EV testing using electron microscopy (EM) between July 2008 and July 2009. Retesting spiked negative stool samples and Salmon DNA as internal control were used to evaluate inhibition. EVPrtPCR detected viruses in significantly more samples: 748 (34%) as compared to 94 (3.8%) by EM. EM did not detect any norovirus, sapovirus, and mixed infection, and detected only 39% of rotavirus and 38.2% of enteric adenovirus positive samples. Four samples that tested positive for rotavirus and two for adenovirus and for small-round-structured viruses by EM were negative by EVPrtPCR. Norovirus was the most common virus detected (17.6%) with 92.4% as genogroup II, followed by rotavirus (6.8%), sapovirus (4.2%), astrovirus (2.0%), and enteric adenovirus (1.4%) with 9% samples positive for mixed infection. Overall, EV identification followed a U-shaped age distribution; positive samples were more common in children ≤5 years old and adults >60 years old. Norovirus, sapovirus and astrovirus showed winter predominance and rotavirus peaked in the spring. No inhibition was observed. Molecular technology significantly enhanced the identification of EV causing sporadic gastroenteritis in Alberta.

Effects of rainfall events on the occurrence and detection efficiency of viruses in river water impacted by combined sewer overflows

Rainfall events can introduce large amount of microbial contaminants including human enteric viruses into surface water by intermittent discharges from combined sewer overflows (CSOs). The present study aimed to investigate the effect of rainfall events on viral loads in surface waters impacted by CSO and the reliability of molecular methods for detection of enteric viruses. The reliability of virus detection in the samples was assessed by using process controls for virus concentration, nucleic acid extraction and reverse transcription (RT)-quantitative PCR (qPCR) steps, which allowed accurate estimation of virus detection efficiencies. Recovery efficiencies of poliovirus in river water samples collected during rainfall events (<10%) were lower than those during dry weather conditions (>10%). The log10-transformed virus concentration efficiency was negatively correlated with suspended solid concentration (r2=0.86) that increased significantly during rainfall events. Efficiencies of DNA extraction and qPCR steps determined with adenovirus type 5 and a primer sharing control, respectively, were lower in dry weather. However, no clear relationship was observed between organic water quality parameters and efficiencies of these two steps. Observed concentrations of indigenous enteric adenoviruses, GII-noroviruses, enteroviruses, and Aichi viruses increased during rainfall events even though the virus concentration efficiency was presumed to be lower than in dry weather. The present study highlights the importance of using appropriate process controls to evaluate accurately the concentration of water borne enteric viruses in natural waters impacted by wastewater discharge, stormwater, and CSOs.

Detection and characterization of human pathogenic viruses circulating in community wastewater using multi target microarrays and polymerase chain reaction

Sewage pollution remains the most significant source of human waterborne pathogens. This study describes the detection and characterization of human enteric viruses in community wastewaters using cell culture coupled with multiple target microarrays (with a total of 780 unique probes targeting 27 different groups of both DNA and RNA viruses) and polymerase chain reaction (PCR) assays. Over a 13-month sampling period, RNA viruses (astroviruses and enteroviruses) were more frequently detected compared to DNA viruses (adenoviruses, particularly type 41 and BK polyomavirus). Overall, many more viruses were shed during the winter months (December-February) compared to the summer months. Exploration of the multiple types of enteric viruses particularly in winter months identified much more significant prevalence of key viral pathogens associated with sewage pollution of the water environment than previously realized and seasonal disinfection used in some parts of the world may lead to a seeding of ambient waters. Molecular characterization of pathogenic viruses in community wastewater will improve the understanding of the potential risk of waterborne disease transmission of viral pathogens.

Detection of enteric viruses in Hungarian surface waters: first steps towards environmental surveillance

Waterborne viruses infect the human population through the consumption of contaminated drinking water and by direct contact with polluted surface water during recreational activity. Although water related viral outbreaks are a major public health concern, virus detection is not a part of the water quality monitoring scheme, mainly due to the absence of routine analysis methods. In the present study, we implemented various approaches for water concentration and virus detection, and tested on Hungarian surface water samples. Eighty samples were collected from 16 sites in Hungary. Samples were concentrated by glass wool and membrane filtration. Human adenoviruses were detected by conventional and quantitative real-time polymerase chain reaction (PCR) methods in 56% (45/80) of the samples; viral titers ranged from 8.60 × 10(1) to 3.91 × 10(4) genome copies per liter. Noroviruses and enteroviruses were detected in 30% (24/80) and 13% (10/80) of samples, respectively, by reverse transcription-PCR assays. Results indicate a high prevalence of viral human pathogens in surface waters, suggesting the necessity of a detailed survey focusing on the quality of natural bathing waters and drinking water sources.