Evaluation of fecal immunoassays for canine Echinococcus infection in China.

Liying Wang,Hu Wang,Roger Frutos,Min Qin,Yu Feng,Qian Wang,Huixia Cai,Sylvie Manguin,Weiping Wu,Yan Huang,Laurent Gavotte,Xuefei Bai,Francesca Tamarozzi

doi:10.1371/journal.pntd.0008690

Abstract

Human echinococcosis is present worldwide but it is in China that disease prevalence is the highest. In western China, especially in the Tibetan Plateau, the burden of echinococcosis is the most important. Dogs are a major definitive host of Echinococcus and monitoring the presence of Echinococcus worms in dogs is therefore essential to efficiently control the disease. Detection kits based on three different technologies including sandwich ELISA, (indirect) ELISA, and gold immunodiffusion, are currently marketed and used in China. The objective of this work was to assess the efficacy of these kits, in particular with respect to sensitivity and specificity. Four fecal antigen detection kits for canine infection reflecting the three technologies were obtained from companies and tested in parallel on 220 fecal samples. The results indicate that the performance is lower than expected, in particular in terms of sensitivity. The best results were obtained with the sandwich ELISA technology. The gold immunofiltration yielded the poorest results. In all cases, further development is needed to improve the performance of these kits which are key components for the control of echinococcosis.

Highlights

Echinococcosis is a health-threatening parasitic zoonotic disease caused by the larval stage of Echinococcus tapeworms [1]
Human echinococcosis is at its highest prevalence in western China and in the Tibetan Plateau
Commercial detection kits are currently in use in China to monitor the presence of Echinococcus in dogs

Summary

Introduction

Echinococcosis is a health-threatening parasitic zoonotic disease caused by the larval stage of Echinococcus tapeworms [1]. Cystic echinococcosis (CE) and alveolar echinococcosis (AE) in humans, livestock, and small mammals, are triggered by the involuntary consumption of Echinococcus granulosus and Echinococcus multilocularis eggs, respectively, excreted in the feces of definitive hosts (e.g., carnivores). The transmission occurs between definitive hosts (primarily dogs and foxes) and intermediate hosts (livestock and small mammals), whilst humans are accidental hosts. Human infection can occur through direct contact with definitive hosts or indirectly through contamination of food or possibly water with parasite eggs [2]. Metacestode infection causes severe disease and possibly death. It results in economic losses from treatment costs, lost wages, and livestock-associated production losses

Objectives

Methods

Results

Discussion

Conclusion