Typically the pathogens found in sewage are sourced from human waste and the vast majority are removed during processing of the biosolids. Most of these pathogens, in particular viruses, do not infect other animals as they are specific for humans. However, a few pathogens, such as some strains of the protozoan parasite Cryptosporidium, can infect certain domestic animals, including cattle and the bacterium Salmonella is known to infect young chickens. This is why the various Biosolids Guidelines recommend a withholding period of 30 days before stock is allowed to graze or domestic fowl allowed access to land once Biosolids have been applied.
This withholding period is not required for domestic animals such as dogs and native wildlife as they cannot become infected with these human pathogens.