What type of bacteria does NOT cause disease?

Nonpathogenic bacteria are those that do not cause disease. They are generally harmless and can even be beneficial, contributing to vital processes such as digestion and the maintenance of ecological balance. Many nonpathogenic bacteria live naturally in the human body, helping to protect against pathogens and maintaining overall health.

On the other hand, pathogenic bacteria are responsible for illnesses and infections, while contagious refers to diseases that can be transmitted from one person to another. Infectious pertains to diseases caused by pathogens, including bacteria, viruses, fungi, and parasites, that can invade the body and cause infection. This context clarifies the distinction between different types of bacteria and their roles in health and disease, solidifying why nonpathogenic bacteria do not cause disease.