This image shows a hand infected with scabies with acute inflammatory edema. Scabies is a contagious skin infection caused by the mite Sarcoptes scabiei burrowing into the skin and laying its eggs. Often this causes itching and the urge to scratch leads to broken and then infected skin. Chromolithograph, 1878-1888. Illustration by E. Burgess after R. W. Sherwin, Mabel Green and Jonathan Hutchinson.