{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T13:47:11Z","timestamp":1785937631539,"version":"3.56.0"},"reference-count":57,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,5]]},"abstract":"<jats:title>ABSTRACT.<\/jats:title>\n                  <jats:p>\n                    Spotted fever group rickettsioses (SFGR) are a growing public health concern in the United States. The increase in SFGR cases, coupled with the geographical expansion of tick species, including\n                    <jats:italic>Amblyomma americanum<\/jats:italic>\n                    and\n                    <jats:italic>A. maculatum<\/jats:italic>\n                    , necessitates a better understanding of\n                    <jats:italic>Rickettsia<\/jats:italic>\n                    species prevalence in newly established areas.\n                    <jats:italic>Amblyomma maculatum<\/jats:italic>\n                    is concerning because of its role as a\n                    <jats:italic>Rickettsia parkeri<\/jats:italic>\n                    vector. This study investigated the prevalence of\n                    <jats:italic>Rickettsia<\/jats:italic>\n                    species in ticks collected across 16 counties in southern Illinois, a region experiencing increasing reported SFGR cases. We collected\n                    <jats:italic>A. maculatum<\/jats:italic>\n                    ,\n                    <jats:italic>A. americanum<\/jats:italic>\n                    , and\n                    <jats:italic>Dermacentor variabilis<\/jats:italic>\n                    and tested them by real-time polymerase chain reaction for\n                    <jats:italic>R. amblyommatis<\/jats:italic>\n                    ,\n                    <jats:italic>R. parkeri<\/jats:italic>\n                    , and\n                    <jats:italic>R. rickettsii<\/jats:italic>\n                    and sequencing of the\n                    <jats:italic>gltA<\/jats:italic>\n                    gene for all\n                    <jats:italic>Rickettsia<\/jats:italic>\n                    species.\n                    <jats:italic>Amblyomma maculatum<\/jats:italic>\n                    was found in a wider range of counties than previously reported, with a prevalence of\n                    <jats:italic>R. parkeri<\/jats:italic>\n                    (16.4%) and\n                    <jats:italic>Candidatus<\/jats:italic>\n                    R. andeanae (28.7%).\n                    <jats:italic>R. montanensis<\/jats:italic>\n                    and\n                    <jats:italic>R. bellii<\/jats:italic>\n                    were detected in\n                    <jats:italic>D. variabilis<\/jats:italic>\n                    ;\n                    <jats:italic>A. americanum<\/jats:italic>\n                    exhibited prevalences of\n                    <jats:italic>R. amblyommatis<\/jats:italic>\n                    of 48.5% in adults and 48.4% in nymphs. A positive correlation was observed between the density of\n                    <jats:italic>R. amblyommatis<\/jats:italic>\n                    \u2013infected\n                    <jats:italic>A. americanum<\/jats:italic>\n                    and SFGR incidence rates. The range expansion of\n                    <jats:italic>A. maculatum<\/jats:italic>\n                    has introduced\n                    <jats:italic>R. parkeri<\/jats:italic>\n                    and\n                    <jats:italic>Candidatus<\/jats:italic>\n                    R. andeanae to southern Illinois, increasing the diversity of SFGR\u2013causing agents. Although current evidence supports a role for\n                    <jats:italic>A. americanum<\/jats:italic>\n                    as driver of SFGR incidence in this region, continued surveillance is crucial to monitor the impact of\n                    <jats:italic>A. maculatum<\/jats:italic>\n                    expansion and potential shifts in\n                    <jats:italic>Rickettsia<\/jats:italic>\n                    spp. transmission dynamics.\n                  <\/jats:p>","DOI":"10.4269\/ajtmh.25-0674","type":"journal-article","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T12:34:27Z","timestamp":1781786067000},"page":"279-289","source":"Crossref","is-referenced-by-count":0,"title":["Surveillance for Metastriate Ticks and Spotted Fever Group Rickettsioses in Southern Illinois"],"prefix":"10.4269","volume":"115","author":[{"given":"Victoria","family":"Phillips","sequence":"first","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. Matthew","family":"Flenniken","sequence":"additional","affiliation":[{"name":"Department of Entomology, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Levi","family":"Mick","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Leta","family":"Chesser","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Edna","family":"Alfaro","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang-Hyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Holly","family":"Gaff","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brian F.","family":"Allan","sequence":"additional","affiliation":[{"name":"Department of Entomology, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chris M.","family":"Stone","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"},{"name":"Department of Entomology, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Holly C.","family":"Tuten","sequence":"additional","affiliation":[{"name":"Illinois Natural History Survey, Prairie Research Institute, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"},{"name":"Department of Entomology, University of Illinois Urbana-Champaign, Champaign, Illinois, USA;"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"issue":"1","key":"b1","series-title":"Am J Trop Med Hyg","first-page":"72","article-title":"Spatial clustering by disease severity among reported Rocky Mountain spotted fever cases in the United States, 2001\u20132005","volume":"80","author":"Zipser Adjemian","year":"2009"},{"issue":"4","key":"b2","series-title":"Am J Trop Med Hyg","first-page":"713","article-title":"Fatal Rocky Mountain spotted fever in the United States, 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