The person who is most likely to be infected when exposed to food borne pathogens is AN ELDERLY PERSON.
This is because, they have increased risk of contacting food borne illnesses as a result of their weakened immune system. As people age, their immune system become weakened and slower in recognizing and riding the body of harmful pathogens that cause infections. Besides, most elderly people usually have one disease or the other already which they are battling with. All these work together to make them highly susceptible to food borne pathogens.