It is not a matter of getting infected. It is naturally found in the body. The problem is that it is dimorphic (exists in two forms). In its yeast form it does not create much in the way of problems for us. If it switches to its fungal form though, it becomes very dangerous as it forms hyphae that allow it to dig in deep to the tissues and organs. Slightly acidic environments keep it in a yeast form. Alkaline environments convert Candida in to the pathogenic fungal form.
Take for example the Candida infections people can develop after taking Antibiotics . The reason for this is that the Antibiotics kill off the beneficial acid producing bacteria. This shifts parts of the body from the normal acidic pH to an alkaline state promoting the formation of fungal Candida.