Diphtheria and the Schick Test in the Tropics

Abstract

Diphtheria, chiefly in its cutaneous form, is common among natives of the tropics, especially early in youth, and among soldiers reduced by combat to the epidemiologlcal conditions of the natives [long dash] crowding, failure or disability to wash, multiple minor injuries and insect bites. Among the former, cutaneous diphtheria acquired early in life seems quickly to reverse the transient Schick positive state that appears at about six months of age[long dash]an observation made long ago, but hitherto unexplained. Among the latter, especially because of their lower immunity, it is always accompanied by nasopharyngeal diphtheria and sometimes by neurological and cardiac complications. Since the tropically acquired cutaneous disease causes little discomfort, it represents an extremely effective method for disseminating the disease. Spread from military to civilian populations has occurred in this way during both World Wars, especially the second. Historically there is evidence that this experience of the origin of diphtheria from the South has been repeated from ancient times.