Norovirus and rotavirus survival in urine collected from a public ecological sanitation system in Ouagadougou, Burkina Faso.

Urine from urine-diversion toilets (UDTs) is routinely used as fertilizer for urban agriculture in Ouagadougou, Burkina Faso. Because urine from UDTs can be accidentally spoiled by feces, we determined whether virulent enteric viruses could persist in urine that is used for agricultural purposes and pose a threat to human health. Urine samples (N = 60) were first collected from 42 UDTs during the months of January and February 2012 in Ouagadougou and screened negative for the presence of norovirus (NoV) and group A rotavirus (RV). Composite urine from five collection sites was used to determine whether spiked murine norovirus (MNV) and group A bovine rotavirus (boRVA) could remain infectious at 15, 25, and 42 °C over an incubation period of 42 days in phosphate buffered saline (control) and urine. For both viruses, infectivity was determined by plaque assay and the presence of viral genome was evaluated by real-time RT-PCR. A decrease in the infectious titer was observed in composite urines that were experimentally seeded with MNV and boRVA. The decrease in the infectious titer was greater for MNV than for boRVA. Given that MNV was more labile to urine than boRVA was, MNV and boRVA genomes were still detectable after the 42 and 49 days incubation period for MNV and boRVA, respectively. Our data using substitutes of human NoV and RV suggested that there is a virucidal activity of urine against RVs and NoVs, given that the effect was lesser for RV. In spite of disappointing results for boRVA, the use of urine as fertilizer is still promising provided that future safety studies are extended to other enteric viruses.