Raw sewage houses thousands of undiscovered viruses, some of which could have a direct bearing on human health.
James Pipas, Roger Hendrix and Michael Grabe of the University of Pittsburgh detected 234 unknown viruses from 26 different families in raw sewage across North America, Europe and Africa.
“What was surprising was that the vast majority of viruses we found were those that had not been detected or described before,” said Hendrix, the journal mBio reports.
A large number of the known viruses found in raw sewage came from plants, probably owing to the fact that humans eat plants, and plant viruses outnumber other types of viruses in human stools, according to a university statement.
The researchers also developed new computational tools to analyse this data. This approach, called metagenomics, had been done before but not with raw sewage.
The main application of this new technology, said Hendrix, would be to discover new viruses and study gene exchange among viruses.