Drying of Cryptosporidium oocysts and Giardia cysts to slides abrogates use of vital dyes for viability staining

Lucy J Robertson; Stijn Casaert; Yazel Valdez-Nava; Md Amimul Ehsan; Edwin Claerebout

doi:10.1016/j.mimet.2013.11.001

Drying of Cryptosporidium oocysts and Giardia cysts to slides abrogates use of vital dyes for viability staining

J Microbiol Methods. 2014 Jan:96:68-9. doi: 10.1016/j.mimet.2013.11.001. Epub 2013 Nov 12.

Authors

Lucy J Robertson¹, Stijn Casaert², Yazel Valdez-Nava³, Md Amimul Ehsan⁴, Edwin Claerebout²

Affiliations

¹ Parasitology Lab, Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O. Box 8146 Dep., Oslo 0033 Norway. Electronic address: lucy.robertson@nvh.no.
² Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, B9820 Merelbeke, Belgium.
³ Parasitology Lab, Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, P.O. Box 8146 Dep., Oslo 0033 Norway.
⁴ Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, B9820 Merelbeke, Belgium; Department of Medicine, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.

PMID: 24239946
DOI: 10.1016/j.mimet.2013.11.001

Abstract

Vital dye staining has long been used to assess viability of Cryptosporidium oocysts and Giardia cysts, with staining and enumeration in suspension. Some recent studies, however, have dried samples to microscope slides prior to staining. Here we demonstrate that this approach may considerably underestimate parasite viability in the original sample.

Keywords: Cryptosporidium; Cyst; Giardia; Oocyst; Staining; Viability.

MeSH terms

Cell Survival
Coloring Agents / metabolism
Cryptosporidium / isolation & purification
Cryptosporidium / physiology*
Desiccation*
Giardia / isolation & purification
Giardia / physiology*
Oocysts / physiology*
Parasitology / methods*
Specimen Handling / methods*
Staining and Labeling / methods*

Substances

Coloring Agents