Detection of Trypanosoma lewisi from wild rats in Southern China and its genetic diversity based on the ITS1 and ITS2 sequences

Tang, HJ; Lan, YG; Wen, YZ; Zhang, XC; Desquesnes, M; Yang, TB; Hide, G; Lun, ZR

Abstract

Trypanosoma lewisi has widely been considered as a non-pathogenic rat trypanosome. However, more
and more cases of humans infected with T. lewisi have been reported around the world, indicating that
it can infect humans in some undetermined circumstances. Quick and sensitive diagnosis of infection
by T. lewisi is important for both treatment of patients and epidemiological studies of this parasite. In this
paper, three methods i.e. wet blood smear (diagnosis by microscopy), PCR and LAMP were used to detect
T. lewisi from 238 wild rats (Rattus norvegicus) collected from the field in Huadu, Guangdong province,
China. Infection rates of these samples detected by the 3 methods was 6.7% (16/238), 12.6% (30/238),
and 18.9% (45/238), respectively. LAMP could detect all samples shown positive by microscopical observation
of wet smear and by single PCR indicating good potential for application in the detection of T. lewisi.
So far as we know, this is the first report of the LAMP method being used to detect T. lewisi in wild rats.
The specific T. lewisi LAMP primers were able to amplify the target fragment from the genomic DNA of 19
T. lewisi strains isolated from Huadu, Guangdong province (n = 16), Changchun, Jilin province of China
(n = 1) and from Thailand (n = 2). Based on the analyses of ITS1 (internal transcribed spacer 1) and
ITS2 sequences, these 19 strains show a very close genetic relationship with over 96–97% similarity to
the other corresponding sequences of T. lewisi published in Genbank. Phylogenetic trees of the species
in the subgenus Herpetosoma were constructed, based on the ITS1 and ITS2 sequences, and these results
also indicate that they are closely related and in the same clade.

Citation

Tang, H., Lan, Y., Wen, Y., Zhang, X., Desquesnes, M., Yang, T., …Lun, Z. (2012). Detection of Trypanosoma lewisi from wild rats in Southern China and its genetic diversity based on the ITS1 and ITS2 sequences. Infection, Genetics and Evolution, 12(5), 1046-1051. https://doi.org/10.1016/j.meegid.2012.02.018

• Journal Article Type: Article
• Publication Date: Jan 1, 2012
• Deposit Date: Sep 11, 2012
• Journal: Infection, Genetics and Evolution
• Print ISSN: 1567-1348
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 5
• Pages: 1046-1051
• DOI: https://doi.org/10.1016/j.meegid.2012.02.018
• Publisher URL: http://dx.doi.org/10.1016/j.meegid.2012.02.018