EVIDENCE OF PROTOZOAN AND BACTERIAL INFECTION AND CO-INFECTION AND PARTIAL BLOOD FEEDING IN THE INVASIVE TICK HAEMAPHYSALIS LONGICORNIS IN PENNSYLVANIA

Keith J Price; Noelle Khalil; Bryn J Witmier; Brooke L Coder; Christian N Boyer; Erik Foster; Rebecca J Eisen; Goudarz Molaei

doi:10.1645/22-122

EVIDENCE OF PROTOZOAN AND BACTERIAL INFECTION AND CO-INFECTION AND PARTIAL BLOOD FEEDING IN THE INVASIVE TICK HAEMAPHYSALIS LONGICORNIS IN PENNSYLVANIA

J Parasitol. 2023 Jul 1;109(4):265-273. doi: 10.1645/22-122.

Authors

Keith J Price¹, Noelle Khalil^{2

3}, Bryn J Witmier¹, Brooke L Coder¹, Christian N Boyer¹, Erik Foster⁴, Rebecca J Eisen⁴, Goudarz Molaei^{2

3

5}

Affiliations

¹ Division of Vector Management, Pennsylvania Department of Environmental Protection, 2575 Interstate Drive, Harrisburg, Pennsylvania 17110.
² Center for Vector Biology and Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-Borne Diseases, Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, Connecticut 06511.
³ Department of Entomology, Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, Connecticut 06511.
⁴ Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, Colorado 80521.
⁵ Department of Epidemiology of Microbial Diseases, Yale School of Public Health, 60 College Street, New Haven, Connecticut 06510.

PMID: 37436911
PMCID: PMC10658867 (available on 2024-07-12)
DOI: 10.1645/22-122

Abstract

The Asian longhorned tick, Haemaphysalis longicornis, an invasive tick species in the United States, has been found actively host-seeking while infected with several human pathogens. Recent work has recovered large numbers of partially engorged, host-seeking H. longicornis, which together with infection findings raises the question of whether such ticks can reattach to a host and transmit pathogens while taking additional bloodmeals. Here we conducted molecular blood meal analysis in tandem with pathogen screening of partially engorged, host-seeking H. longicornis to identify feeding sources and more inclusively characterize acarological risk. Active, statewide surveillance in Pennsylvania from 2020 to 2021 resulted in the recovery of 22/1,425 (1.5%) partially engorged, host-seeking nymphal and 5/163 (3.1%) female H. longicornis. Pathogen testing of engorged nymphs detected 2 specimens positive for Borrelia burgdorferi sensu lato, 2 for Babesia microti, and 1 co-infected with Bo. burgdorferi s.l. and Ba. microti. No female specimens tested positive for pathogens. Conventional PCR blood meal analysis of H. longicornis nymphs detected avian and mammalian hosts in 3 and 18 specimens, respectively. Mammalian blood was detected in all H. longicornis female specimens. Only 2 H. longicornis nymphs produced viable sequencing results and were determined to have fed on black-crowned night heron, Nycticorax nycticorax. These data are the first to molecularly confirm H. longicornis partial blood meals from vertebrate hosts and Ba. microti infection and co-infection with Bo. burgdorferi s.l. in host-seeking specimens in the United States, and the data help characterize important determinants indirectly affecting vectorial capacity. Repeated blood meals within a life stage by pathogen-infected ticks suggest that an understanding of the vector potential of invasive H. longicornis populations may be incomplete without data on their natural host-seeking behaviors and blood-feeding patterns in nature.

Keywords: Babesia microti; Borrelia burgdorferi; Haemaphysalis longicornis; Co-infection; Mid-Atlantic United States; Partial blood meal.

Publication types

Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.

MeSH terms

Animals
Bacterial Infections*
Coinfection* / epidemiology
Coinfection* / veterinary
Ixodes* / microbiology
Ixodidae*
Nymph
Pennsylvania / epidemiology
Ticks*