Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Sep;67(6):637-650.
doi: 10.1111/zph.12743. Epub 2020 Jul 7.

First glimpse into the origin and spread of the Asian longhorned tick, Haemaphysalis longicornis, in the United States

Affiliations

First glimpse into the origin and spread of the Asian longhorned tick, Haemaphysalis longicornis, in the United States

Andrea Egizi et al. Zoonoses Public Health. 2020 Sep.

Abstract

Established populations of Asian longhorned ticks (ALT), Haemaphysalis longicornis, were first identified in the United States (US) in 2017 by sequencing the mitochondrial cytochrome c oxidase subunit I (cox1) 'barcoding' locus followed by morphological confirmation. Subsequent investigations detected ALT infestations in 12, mostly eastern, US states. To gain information on the origin and spread of US ALT, we (1) sequenced cox1 from ALT populations across 9 US states and (2) obtained cox1 sequences from potential source populations [China, Japan and Republic of Korea (ROK) as well as Australia, New Zealand and the Kingdom of Tonga (KOT)] both by sequencing and by downloading publicly available sequences in NCBI GenBank. Additionally, we conducted epidemiological investigations of properties near its initial detection locale in Hunterdon County, NJ, as well as a broader risk analysis for importation of ectoparasites into the area. In eastern Asian populations (China/Japan/ROK), we detected 35 cox1 haplotypes that neatly clustered into two clades with known bisexual versus parthenogenetic phenotypes. In Australia/New Zealand/KOT, we detected 10 cox1 haplotypes all falling within the parthenogenetic cluster. In the United States, we detected three differentially distributed cox1 haplotypes from the parthenogenetic cluster, supporting phenotypic evidence that US ALT are parthenogenetic. While none of the source populations examined had all three US cox1 haplotypes, a phylogeographic network analysis supports a northeast Asian source for the US populations. Within the United States, epidemiological investigations indicate ALT can be moved long distances by human transport of animals, such as horses and dogs, with smaller scale movements on wildlife. These results have relevant implications for efforts aimed at minimizing the spread of ALT in the United States and preventing additional exotic tick introductions.

Keywords: animal diseases; environment and public health; introduced species; population genetics; tick infestations; tick-borne diseases.

PubMed Disclaimer

References

REFERENCES

    1. Arndt, P. F. (2007). Reconstruction of ancestral nucleotide sequences and estimation of substitution frequencies in a star phylogeny. Gene, 390(1-2), 75-83. https://doi.org/10.1016/j.gene.2006.11.022
    1. Barker, S. C., & Walker, A. R. (2014). Ticks of Australia. The species that infest domestic animals and humans. Zootaxa, 3816(1), 1-144. https://doi.org/10.11646/zootaxa.3816.1.1
    1. Beard, C. B., Occi, J., Bonilla, D. L., Egizi, A. M., Fonseca, D. M., Mertins, J. W., … Halperin, W. (2018). Multistate infestation with the exotic disease-vector tick Haemaphysalis longicornis - United States, August 2017-September 2018. MMWR, 67(47), 1310-1313. https://doi.org/10.15585/mmwr.mm6747a3
    1. Berrada, Z. L., & Telford, S. R. 3rd (2009). Burden of tick-borne infections on American companion animals. Topics in Companion Animal Medicine, 24(4), 175-181. https://doi.org/10.1053/j.tcam.2009.06.005
    1. Bertelsmeier, C., Ollier, S., Liebhold, A. M., Brockerhoff, E. G., Ward, D., & Keller, L. (2018). Recurrent bridgehead effects accelerate global alien ant spread. Proceedings of the National Academy of Sciences, 115(21), 5486. https://doi.org/10.1073/pnas.1801990115

Publication types

Substances

Associated data

LinkOut - more resources