sure! just wear a red "x", we'll seal your fate.
"A red cross or 'x' to warn the public not to go inside the house and show to the plague doctors which house/s to watch. The person or people inside of a marked house were locked inside with the others in the house even if there were healthy people inside of it. soon,the infected in the house would pass on infections to the healthier and everyone in the house would die. 1-2 weeks later, plague doctors with long beak shaped masks (stuffed with lavender to stop the terrible smell) would burst down marked doors and haul the bodies into deep pits dug randomly about sites of the plague ridden areas." -Answers.com