Simple and effective method for observation of suspended parasite specimens using vaseline and paraffin mixture

Parasitic specimens derived from protozoans and helminths have variable thickness. Therefore, microscopic observation of these specimens requires a preparation technique where the space between the coverslip and slide glass can be freely adjusted. However, standard suspension methods for parasites do not afford this flexibility due to the thickness of eggs and parasites. Mounting too large of a sample results in a floating coverslip, making observation difficult. In this article, we developed vaseline-paraffin solution (VPS) as a simple and effective mounting technique for observation of suspended parasite specimens. VPS placed between the coverslip and slide glass makes it possible to adjust the space between to accommodate specimens of variable thickness. For example, patterning of Toxocara egg surface protein layers can be observed using this improved method. Furthermore, VPS can be used as a sealing medium for long-term preservation. It is possible to keep suspended parasite specimens for more than two weeks.