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

• Virus in sediment poses a serious threat of water body contamination.
• All properties presented contamination by enteric viruses.
• Fecal contamination from both animal and human origins may be found in the farms.
• Animal viruses are good indicators of animal fecal contamination.
• Adenovirus infectious particles found in both sediment and water samples in 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 × 102 gc/L up to 6.68 × 109 gc/L (water), and from 1.97 × 103 gc/g to 2.18 × 108 gc/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.