Comparison of three LAMP protocols for the simultaneous detection of DNA from species that produce cystic echinococcosis

Abstract

Cystic echinococcosis (CE) is a zoonotic parasitic disease caused by species of the Echinococcus granulosus sensu lato complex. Different types of canids may act as definitive hosts by eating raw viscera infected with fertile hydatid cysts. The intermediate host (mainly ungulates) and humans acquire the infection through the fecal oral route (i.e. egg ingestion). Globally, more than 1 million people are affected by CE, causing a loss of 1-3 million disability-adjusted life years (DALYs) and a financial burden of US$ 3 billion annually. Loop mediated isothermal amplification (LAMP) protocols promise to be a useful tool to detect DNA, providing a low cost and thermocycle-free methodology. Given that surveillance for CE can be performed in feces from canids or other environmental matrixes contaminated with eggs, the characteristics of a LAMP protocol would favor implementation in endemic areas with basic resources. Herein, we compared three LAMP protocols for the simultaneous detection of E. granulosus s.l. species that cause CE. This comparation was carried with DNA obtained from different stages of E. granulosus s.l. Two of these are newly developed protocols that showed good analytical sensitivity and specificity. In both cases, the use of malachite green dye to directly visualize the test result was possible. From these two new LAMP protocols, one had better values for the detection of DNA from different types of E. granulosus s.l. DNA samples. Therefore, through this study, we provide a low-cost new tool for DNA detection of E. granulosus s.l. in poorly equipped laboratories from endemic areas.