ADENOVIRUS AND NOROVIRUS IN WATER AND SEDIMENTS OF RECREATIONAL AQUATIC ENVIRONMENTS: COMPARISON OF CONCENTRATION, RECOVERY, AND DETECTION METHODS

CHÁVEZ DÍAZ LUCÍA; TULIO MACHADO; HUGO RAMIRO POMA; DOLORES GUTIÉRREZ CACCIABUE; MARIZE MIAGOSTOVICH; VERÓNICA RAJAL

Florianópolis

Simposio; IV Latin American Symposium on Environmental Virology; 2018

Aquatic environments are intensively usedfor public recreational activities. In some cases, rivers and lakes become arisk to population due to the presence of some viruses that transmit waterbornediseases. Pathogens are not only found in water but also in sediments, whichmay act as a reservoir. An eventually resuspension of sediments could returnmicroorganism to the water column. Since viruses are in general at low amountsin natural aquatic environments, a concentration step before the detection is necessary.The aim of this work was to analyze different methods to detect adenovirus and norovirusgenogroup I and II in two recreational aquatic environments in Salta,Argentina. Water and sediment samples(3 replicates per occasion) were collected from December 2015 to September 2016from the Wierna River (WR) (5 samples, 15 in total) and General BelgranoReservoir (GBR) (6 samples, 18 in total). Water samples were concentrated byultrafiltration using PP7 recovery control and nucleic acids were extractedwith commercial QIAamp ViralRNA Mini Kit (Qiagen, Germany). Adenovirus was analyzed by real-time PCR (qPCR) with two different setsof previously published primers (here referred as OS1 and OS2). Norovirus GI and GII were analyzed with the sameprimers and probes, butin the first case a RT was carried out followed by qPCR, and in the second aone-step quantitative multiplex RT-PCR system was used. For sediments, two nucleicacids extraction methods were used: i) Mobio PowerSoil DNA kit; and ii) skimmed-milk flocculation method (using PP7 as arecovery control), followed by nucleic acidsextraction with QIAamp Viral RNA Mini Kit. Using OS1, which targeted only gastrointestinal-related species (HAdV-F types 40and 41), 13% and 11% positives cases of adenovirus in water were found at WRand GBR, respectively. Instead using OS2, which targeted all human adenovirus species, 40% and 83%positives samples were detected in water at each place, respectively. Regardingnorovirus detection, only GII was detected in 20% and 11% of water samples fromWR and GBR, respectively. Using the skimmed-milk flocculation method in sediments, adenovirus wasdetected in all samples of both environments, and norovirus GII was detected inone river and one reservoir samples. Only one positive sample for adenoviruswas found using the MoBio kit. The desorption-concentrationstep in sediments seemed to be crucial for the recovery and detection of viruses.