The bacterial flora of the forehead and back of Alaskan native villagers in summer and in winter.

The bacterial flora of the forehead and back of Eskimo and Indian villagers in arctic Alaska was determined in midsummer and in winter (temperature -29 degrees to -46 degrees C). Specimens collected by the wet swab method were transported overnight, chilled, to Seattle in buffered diluent with Triton X-100. Control tests showed good survival of principal skin organisms with moderate or large initial populations and a disproportionately greater loss with an initial sparse population. Results of these studies are compared with earlier studies of the forehead flora of a Seattle urban population. On most Alaskan subjects Propionibacterium acnes was more abundant than staphylococci on both sites and both organisms had greater population densities on the forehead than on the back. Population densities for P. acnes varied from none detected to more than 10(6) per cm2 on the forehead and 10(5) per cm2 on the back. For coagulase-negative staphylococci the range was from none detected to more than 10(5) per cm2 on the forehead and the back. The proportion of subjects with relatively abundant or relatively sparse populations of P. acnes and of staphylococci did not change seasonally. Of 51 staphylococcal isolates, 65% were S. epidermidis, 22% S. capitis, and 10% S. hominis. P. saccharolyticus was found on a minority of subjects on both sites. The kinds of organisms found on the forehead and their variable individual population densities were essentially the same on the Alaskan villagers and the Seattle subjects.