Prevalence of Amebiasis in the United States and Canada

Abstract

Summary A study was made of the prevalence of Entamoeba histolytica as reported in 166 surveys on nearly a quarter of a million persons in the United States and Canada. Previous estimates of 10 to 20 per cent prevalence of amebiasis in the United States were found to be much too high because of the inclusion of E. hartmanni and because the majority of surveys were done on groups expected to show a high prevalence of amebiasis. The present estimate is that about 1 per cent or less of the population of Alaska and Canada and less than 5 per cent of the United States population harbor E. histolytica. Suggestions are made regarding procedures for future surveys.