Parasites & Vectors (May 2014)

Loop-Mediated Isothermal Amplification (LAMP) assay for the identification of Echinococcus multilocularis infections in canine definitive hosts

  • Xingwei Ni,
  • Donald P McManus,
  • Hongbin Yan,
  • Jifei Yang,
  • Zhongzi Lou,
  • Hongmin Li,
  • Li Li,
  • Mengtong Lei,
  • Jinzhong Cai,
  • Yanlei Fan,
  • Chunhua Li,
  • Quanyuan Liu,
  • Wangui Shi,
  • Xu Liu,
  • Yadong Zheng,
  • Baoquan Fu,
  • Yurong Yang,
  • Wanzhong Jia

DOI
https://doi.org/10.1186/1756-3305-7-254
Journal volume & issue
Vol. 7, no. 1
pp. 1 – 8

Abstract

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Abstract Background Alveolar echinococcosis, caused by the metacestode larval stage of Echinococcus multilocularis, is a zoonosis of public health significance and is highly prevalent in northwest China. To effectively monitor its transmission, we developed a new rapid and cheap diagnostic assay, based on loop-mediated isothermal amplification (LAMP), to identify canine definitive hosts infected with E. multilocularis. Methods The primers used in the LAMP assay were based on the mitochondrial nad 5 gene of E. multilocularis and were designed using Primer Explorer V4 software. The developed LAMP assay was compared with a conventional PCR assay, using DNA extracted from the feces of dogs experimentally infected with E. multilocularis, on 189 dog fecal samples collected from three E. multilocularis-endemic regions in Qinghai province, the People’s Republic of China, and 30 negative control copro-samples from dogs from an area in Gansu province that had been subjected to an intensive de-worming program. Light microscopy was also used to examine the experimentally obtained and field collected dog copro-samples for the presence of E. multilocularis eggs. Results The E. multilocularis-positivity rates obtained for the field-collected fecal samples were 16.4% and 5.3% by the LAMP and PCR assays, respectively, and all samples obtained from the control dogs were negative. The LAMP assay was able to detect E. multilocularis DNA in the feces of experimentally infected dogs at 12 days post-infection, whereas the PCR assay was positive on the 17th day and eggs were first detectable by light microscopy at day 44 post-challenge. Conclusion The earlier specific detection of an E. multilocularis infection in dog copro-samples indicates that the LAMP assay we developed is a realistic alternative method for the field surveillance of canines in echinococcosis-endemic areas.

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