Intestinal parasites are a concern in veterinary medicine worldwide and for human health in the developing world. Infections are identified by microscopic visualisation of parasite eggs in faeces, which is time-consuming, requires technical expertise and is impractical for use on-site. For these reasons, recommendations for parasite surveillance are not widely adopted and parasite control is based on administration of rote prophylactic treatments with anthelmintic drugs. This approach is known to promote anthelmintic resistance, so there is a pronounced need for a convenient egg counting assay to promote good clinical practice. Using a fluorescent chitin-binding protein, we show that this structural carbohydrate is present and accessible in shells of ova of strongyle, ascarid, trichurid and coccidian parasites. Furthermore, we show that a cellular smartphone can be used as an inexpensive device to image fluorescent eggs and, by harnessing the computational power of the phone, to perform image analysis to count the eggs. Strongyle egg counts generated by the smartphone system had a significant linear correlation with manual McMaster counts (R2 = 0.98), but with a significantly lower coefficient of variation (P = 0.0177). Furthermore, the system was capable of differentiating equine strongyle and ascarid eggs similar to the McMaster method, but with significantly lower coefficients of variation (P < 0.0001). This demonstrates the feasibility of a simple, automated on-site test to detect and/or enumerate parasite eggs in mammalian faeces without the need for a laboratory microscope, and highlights the potential of smartphones as relatively sophisticated, inexpensive and portable medical diagnostic devices.
|Number of pages||9|
|Journal||International Journal for Parasitology|
|State||Published - Jul 1 2016|
Bibliographical noteFunding Information:
This work was partially funded by an Small Business Innovation Research grant from the United States Department of Agriculture , USA (# 2015-33610-23497 ; P.S.) and by grants from MEP Equine Solutions , LLC, USA, (M.K.N.). CBD protein production was supported in part by the UK COBRE Center for Molecular Medicine Protein and Molecular Technologies cores (which are supported in part by National Institutes of Health , USA, Grant Number P20GM110787 ; G.P., K.M.C., M.M., and D.W.R. and National Science Foundation , USA, Grant IIA-1355438 ; D.W.R). We thank Eric Hauck, David Ward, Ellie Hawes and Winston Walker for their assistance in designing and building the imaging units, and Richard Chan for his suggestion of using a cell phone and the Sapphire PrepOne for imaging eggs in McMaster chambers.
© 2016 Australian Society for Parasitology
- Egg count
- Image analysis
ASJC Scopus subject areas
- Infectious Diseases