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Haemaphysalis longicornis, the Asian longhorned tick, is an invasive tick species that has spread rapidly across the northeastern and southeastern regions of the United States in recent years. This invasive pest species, known to transmit several tick-borne pathogens in its native range, is a potential threat to wildlife, livestock, domestic animals, and humans. Questing larval (n = 25), nymph (n = 10), and adult (n = 123), along with host-derived adult (n = 25) H. longicornis ticks were collected from various locations on Staten Island, NY. The pathobiome of each specimen was examined using two different high throughput sequencing approaches, virus enrichment and shotgun metagenomics. An average of 45,828,061 total reads per sample were recovered from the virus enriched samples and an average of 11,381,144 total reads per sample were obtained using shotgun metagenomics. Aside from endogenous viral sequences, no viruses were identified through either approach. Through shotgun metagenomics, Coxiella-like bacteria, Legionella, Sphingomonas, and other bacterial species were recovered. The Coxiella-like agent was ubiquitous and present at high abundances in all samples, suggesting it may be an endosymbiont. The other bacterial agents are not known to be transmitted by ticks. From these analyses, H. longicornis do not appear to host any endemic human tick-borne pathogens in the New York City region., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

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., (© 2020 Blackwell Verlag GmbH.)

Haemaphysalis longicornis, an invasive Ixodid tick, was recently reported in the eastern United States. The emergence of these ticks represents a potential threat for livestock, wildlife, and human health. We describe the distribution, host-seeking phenology, and host and habitat associations of these ticks on Staten Island, New York, a borough of New York City.