The EPI Team The Epidemiological (Epi) Team is a group of individuals that investigates illnesses and sicknesses in order to determine the cause and prevent further spread.  An example would be if fifteen people complain of similar unknown and unusual symptoms. The Epi Team would work to interview subjects, gather medical specimens, and perform other related tasks.  his investigation would lead to a conclusion (in our example of fifteen sick people, it could be they got food poisoning from a local restaurant).  The Epi Team is comprised of senior level health officials. The team takes training to maintain current knowledge and skills.