Enterococcus are a type of bacteria found in human and animal feces and are an indicator of possible sewage contamination. Although they are not harmful themselves, they indicate the possible presence of pathogenic (disease-causing) bacteria, viruses, and protozoans that also live in human and animal digestive systems. Enterococci are able to survive in salt and fresh water, and are typically more human-specific than other fecal indicator bacteria. The U.S. EPA recommends enterococci as the best indicator of health risk in salt water used for recreation and as a useful indicator as fresh water as well.