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VanAcker, M. C.

Publications and source records attributed to VanAcker, M. C..

3 recordsLinked to original sources

Widespread occurrence of bovine-like and new viruses in wild deer across the United States

Over the past several decades, deer populations in North America have grown considerably, resulting in frequent contact with humans and livestock, and increased potential for pathogen spillover. Despite the importance of pathogen spillover among humans, wildlife, and livestock, the diversity of viruses present in deer remains largely unknown. Using a metagenomic high-throughput sequencing approach, we characterized viral communities in the upper respiratory tracts of live mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) captured at fourteen study sites in nine states across the United States. We identified vertebrate-infecting viruses in both deer species at all but two of the study sites, located in Illinois and Utah. Viral richness did not vary among species or study sites. However, viral community composition was different across study sites but not among deer species. Amongst the detected viral sequences, several originate from or were closely related to viruses previously described in humans (e.g., severe acute respiratory syndrome coronavirus 2) and livestock (e.g., bovine-like coronavirus). We also documented viruses recently discovered in deer, such as CHeRI orbivirus 1. Finally, we identified several new putative viruses in the Picornaviridae, Rhabdoviridae and Tobaniviridae families, including a novel Aphthovirus related to bovine rhinitis A virus in both deer species, across seven states and nine study sites. Our findings expand the understanding of viral diversity in two deer species across the United States, providing important insights for managing pathogens at the wildlife, livestock, and human interface.

microbiology↗

Urban greenspace connectivity drive shifts in host assemblages and tick-borne pathogen infection

Habitat fragmentation is often highlighted as a driver of tick-borne disease hazard and spillover risk via reduction in biodiversity. However, habitat fragmentation can have divergent impacts on host, vector, and pathogen dynamics depending on the distribution of fragment sizes and the levels of connectivity to surrounding habitat, particularly when habitat fragments are embedded in an urban matrix. We examine how extreme habitat fragmentation influences host community composition in an urban landscape and determine its cascading impacts on Ixodes scapularis vector abundance and infection prevalence with human pathogenic Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum. We utilize camera-trapping and live mammal-trapping methods to quantify the availability of vertebrate hosts to questing larval ticks and relate relative host activity to the resulting density of nymphs and nymphal infection prevalence; the combination of these metrics determines the tick-borne disease hazard (i.e. the density of infected questing nymphs - DIN). We found that increased habitat connectivity in urban areas shifted the composition of the host community from human-adapted to forest-dependent species, species which inhabit forested habitats for all or a portion of their lifecycles. The resulting increased encounter probability between ticks and forest-dependent species increased the density of nymphs and nymphal infection prevalence with host-limited pathogens, A. microti and A. phagocytophilum, amplifying local tick-borne disease hazard. Host encounter probability of all species examined did not increase B. burgdorferi nymphal infection prevalence, likely due to this pathogens wider host range; whereas increased deer encounter probability decreased the nymphal infection prevalence of B. burgdorferi. These findings emphasize the importance of host identity, rather than host diversity, in shaping the heterogenous distribution of tick-borne pathogen risk in highly fragmented urban forest patches and suggest a non-linear association between disease risk and host biodiversity.

ecology↗

Association of the invasive Haemaphysalis longicornis tick with vertebrate hosts, other native tick vectors, and tick-borne pathogens in New York City

Haemaphysalis longicornis, the Asian longhorned tick, is an invasive ixodid tick that has rapidly spread across the northeastern and southeastern regions of the United States since first reported in 2017. The emergence of H. longicornis presents a potential threat for livestock, wildlife, and human health as the host associations and vector potential of this invasive pest in the United States are poorly understood. Previous field data from the United States has shown that H. longicornis was not associated with natural populations of small mammals or birds, but they show a preference for medium sized mammals in laboratory experiments. Therefore, medium and large sized mammals were sampled on Staten Island, New York to determine H. longicornis host associations and vector potential for a range of human and veterinary pathogens. A total of 97 hosts were sampled and five species of tick (Amblyomma americanum, Dermacentor variabilis, H. longicornis, Ixodes scapularis, Ixodes cookei) were found feeding concurrently on these hosts. Haemaphysalis longicornis was found in the highest proportions compared to other native tick species on raccoons (55.4%), Virginia opossums (28.9%), and white-tailed deer (11.5%). Tissue, blood, and engorged larvae were tested for 17 different pathogens using a nanoscale PCR platform. Infection with five pathogens (Borrelia burgdorferi, Anaplasma phagocytophilum, Rickettsia spp., Mycoplasma haemocanis, and Bartonella spp.) was detected in host samples, but no pathogens were found in any larval samples. These results suggest that although large and medium sized mammals feed large numbers of H. longicornis ticks in the environment there is presently a low potential for H. longicornis to acquire pathogens from these wildlife hosts.HighlightsH. longicornis were sampled from seven genera of large and medium-sized mammalsRaccoons, opossums, and white-tailed deer fed a large proportion of H. longicornisH. longicornis did not acquire pathogens through co-feeding with native tick vectorsHost species were infected with a range of pathogens of human and veterinary concernHost-derived H. longicornis engorged larvae were not infected with any pathogensCompeting Interest StatementThe authors have declared no competing interest.View Full Text

ecology↗