Modified sugar centrifugal flotation technique for recovering Echinococcus multilocularis eggs from soil

Among soil-transmitted parasitic diseases, alveolar hydatidosis due to the ingestion of Echinococcus multilocularis eggs is becoming a serious problem in Hokkaido, the northern most island of Japan. Dissemination of the infection far from the endemic areas can occur if motor vehicles transmit soil contaminated with eggs. No appropriate and validated method for recovering the taeniid eggs from soil is available. A modified sugar centrifugal flotation technique, using a sucrose solution of specific gravity 1.27 and 0.05% Tween-80, was evaluated as a method to successfully recover eggs from soil. Contamination levels as low as 10 eggs per gram could be detected. This method may be useful to determine the prevalence of E. multilocularis, its transmission, and the potential for by monitoring soil contamination with eggs.