A sample of returned travelers who sought health care from 2007 through 2011 at any of 53 international GeoSentinel-associated clinics showed that most people diagnosed with E. histolytica had traveled for tourism to India, Indonesia, Mexico, or Thailand, as opposed to visiting with friends and relatives or traveling for business. Nevertheless, cases of amebiasis are not restricted to these countries and are distributed worldwide, particularly in the tropics, most commonly in areas of poor sanitation.
Molecular methods using the polymerase chain reaction amplify E. histolytica genes from extracted faecal DNA. Sensitivity and specificity are high (80%–100% and 100%, respectively). The advantage of molecular detection is that it is extremely sensitive (able to detect < 1 parasite) and reliably able to differentiate non-pathogenic Entamoeba species from E. histolytica. Drawbacks of this method are the high level of expertise required and the cost.
For symptomatic intestinal infection and extraintestinal disease, treatment with metronidazole or tinidazole should be followed by treatment with iodoquinol or paromomycin. Asymptomatic patients infected with E. histolytica should also be treated with iodoquinol or paromomycin, because they can infect others and because 4%–10% develop disease within a year if left untreated.