In the Zoo Basel, direct contact to the definitive hosts can be
excluded and other routes of infection have to be evaluated. Faecal
contamination of vegetables and fruit can occur under various
circumstances during production, manufacturing, storage or
transport if they are produced in conditions that allow faecal
contaminated waters to be used for irrigation or washing, or if the
soil is contaminated. Vegetables from such sources, if consumed
raw and insufficiently washed, can be a potential source of parasitic
disease . Cultivation in open fields, where wild
animals have access, increases the risk of contamination, especially
since taeniid eggs can remain viable for several months, if conditions
are suitable, as experiments
showed for E. multilocularis eggs .