The common term for bacteria that cause disease is "pathogenic bacteria." These bacteria can lead to infections and various illnesses in humans and animals, depending on the species and the conditions in which they thrive. Pathogenic bacteria can enter the body through different routes, including ingestion, inhalation, or breaks in the skin. Examples include Escherichia coli, Salmonella, and Streptococcus. While many bacteria are harmless or beneficial, pathogenic strains can trigger immune responses and lead to symptoms ranging from mild to severe, necessitating prompt medical attention in some cases.