A trip to Antarctica might not be a dream vacation for everyone, but it’s on the list for many who are clearly willing to trek to there. While tourists are busy exploring the scenery and greeting the penguins who live there, scientists are raising concerns about how exposure to us could increase their risk of contracting infectious diseases. Scientists and disease experts believe the immune systems of penguins, and other species in the region, are less able to deal with pathogens that are commonplace in the rest of the world because they’ve been isolated for so long with few visitors.