Candida fungus exists as a commensal organism on the skin and mucous membranes, typically remaining harmless. However, it can lead to infections under certain conditions. The discussion highlights that not everyone experiences infections from Candida due to various factors, including the specific environment where the fungus is located. For instance, while Streptococcus bacteria are normally present on the skin, they can become pathogenic if introduced into the lungs through actions like inhaling saliva. This shift in environment can facilitate the bacteria's ability to infiltrate the bloodstream, potentially leading to infections, as indicated by symptoms such as swollen lymph nodes. The conversation emphasizes the importance of environmental context in the pathogenicity of microorganisms.
