The Distribution, Seasonal Abundance, and Environmental Factors Contributing to the Presence of the Asian Longhorned Tick (Haemaphysalis longicornis, Acari: Ixodidae) in Central Appalachian Virginia

Abstract

Over the past decade, Haemaphysalis longicornis, the Asian longhorned tick, has undergone a geographic range expansion in the United States, from its historical range in east Asia. This tick has been characterized by its frequent parasitism of livestock, an ability to reproduce through parthenogenesis, and its ability to transmit a variety of vector-borne pathogens to livestock, wildlife, and human hosts in its native geographic range. Thus far in the United States, 17 states have reported H. longicornis populations, including 38 counties in Virginia. These numbers come from presence-absence reports provided to the U.S. Department of Agriculture, but little has been reported about this ticks’ seasonality in Virginia or its habitat preferences. Our current study detected H. longicornis populations in seven of the nine surveyed counties in Virginia. Haemaphysalis longicornis were observed in multiple habitat types including mixed hardwood forests and pastures, with abundant H. longicornis populations detected at one particular pasture site in Wythe County. This study also attempted to investigate environmental conditions that may be of importance in predicting tick presence likelihood. While sample size limited the scope of these efforts, habitat type and climatic metrics were found to be important indicators of H. longicornis collection success and abundance for both the nymphal and larval life stages. This current study reports useful surveillance data for monitoring these tick populations as they become established in the western half of Virginia and provides insight into their current distribution and maintenance over a large study region.

Seasonal Dynamics of Tick Species in the Ecotone of Parks and Recreational Areas in Middlesex County (New Jersey, USA)

“…The seasonal dynamics of H. longicornis we found are similar to previous reports in a suburban area in NJ [ 23 , 30 ] and other eastern USA states [ 31 , 32 , 33 , 34 ]. However, the density of ticks in the ecotone in our study (1.7 ticks per m 2 ) is higher than in other habitats [ 33 , 34 ] and like those found in previous studies conducted in ecotone habitats [ 23 , 30 ].…”

“…This is not surprising since H. longicornis is often found in open meadows and forests in Asia and Oceania, suggesting that this tick species thrives in a wide range of temperature and humidity conditions [ 36 , 37 , 38 ]. In addition, biological factors, such as host availability, are critical for tick development and can drive important differences in tick densities [ 31 , 39 ]. For example, meso-mammals are the primary host for the immature stages in Asia, while in the USA, opossums and raccoons are the main potential hosts [ 40 ].…”

Evidence of Protozoan and Bacterial Infection and Co-Infection and Partial Blood Feeding in the Invasive Tick Haemaphysalis longicornis in Pennsylvania

“…Briefly, active tick surveillance was conducted in all 67 Pennsylvania counties intermittently from 1 October 2020 to 8 April 2021 and weekly from 1 May to 31 August 2021, periods coinciding with peak adult and nymphal I. scapularis and all life stages of H. longicornis activity (Tufts et al, 2019; Piedmonte et al, 2021). Consistent with Centers for Disease Control and Prevention (CDC) recommendations, sampling sites included public areas in deciduous forests, habitats conducive to I. scapularis and H. longicornis tick activity (CDC, 2018; Thompson et al, 2021; Cumbie et al, 2022b). Questing ticks were collected by dragging a 1 m 2 white felt cloth across the forest floor over vegetation/leaf litter for ≥100 m per collection occasion.…”

Environmental variables serve as predictors of the invasive Asian longhorned tick (Haemaphysalis longicornis Neumann): An approach for targeted tick surveillance

“…Reports of H . longicornis collected in Virginia, Delaware, New Jersey, and Pennsylvania, indicate larvae quest August through October, nymphs quest May through June, and adults quest July through August [ 17 – 21 ]. Virginia researchers also investigated several environmental variables associated with the presence of H .…”

“…Virginia researchers also investigated several environmental variables associated with the presence of H . longicornis and found average daily temperature, habitat type, and precipitation metrics were associated with questing populations [ 21 ]. Knowing these variables and discovering additional variables associated with populations can allow stakeholders to better understand when and where these species occur.…”