If not treated the person can die and infect others as well.
You can die
you explode
It depends on what and how debilitating it is
Diphtheria is an infectioncaused by the bacterium Corynebacterium diphtheriae.
He would be in a bad predicament.
An untreated infection may spread to the lymphatic system (acute lymphangitis ), the lymph nodes (lymphadenitis ), the bloodstream (bacteremia ), or into deeper tissues.
Diphtheria primarily attacks the respiratory system, causing severe throat inflammation, difficulty breathing, and the formation of a thick gray membrane in the throat. It can also affect the cardiovascular system, leading to complications such as myocarditis, and the nervous system, potentially causing peripheral neuropathy and other neurological issues. If left untreated, diphtheria can lead to serious complications in multiple organ systems.
flea infestation can cause a puppy to develop anemia and die if left untreated
It will burn the lining of the mouth, throat, esophagus and stomach. If left untreated, you will be in agony until you finally die.
the bacterial infection can destroy skin, tissue, and bone or spread throughout the body.
millions of people will be left untreated and maybe die and we have an economic collapse.
Cats and dogs can die it heart worm is left untreated. Call your vet.