About

Barbara Qurollo is a research associate professor at North Carolina State University College of Veterinary Medicine. She obtained her Doctor of Veterinary Medicine (DVM) degree from Colorado State University and completed an internship in Emergency Medicine and Critical Care in Milwaukee, Wisconsin. Following her internship, she spent three years studying vector-borne diseases in companion animals as a Postdoctoral Research Scholar at NC State's College of Veterinary Medicine. Her research efforts are focused on vector-borne disease in wildlife and companion animals, as well as on developing improved methods for detecting diseases across wildlife, pets, domesticated animals, and humans. She is affiliated with the North Carolina Veterinary Medical Association, the Comparative Medicine Institute at NCSU, and the International Society for Companion Animal Infectious Diseases.

Research topics

• Virology
• Immunology
• Medicine
• Microbiology
• Veterinary medicine
• Internal medicine
• Biology

Selected publications

• Isolation, culture, and genome analysis of Rickettsia oklahomensis sp. nov. (Rickettsiales: Rickettsiaceae) from Amblyomma americanum (Acari: Ixodidae)

  Ticks and Tick-borne Diseases · 2025-04-18 · 1 citations

  articleOpen accessSenior author

  An uncharacterized Rickettsia species was previously identified by molecular detection in Amblyomma americanum ticks from Oklahoma, a state reported to have high Rickettsia seroprevalence. Amblyomma americanum ticks are aggressive feeders capable of transmitting viral, protozoal and bacterial species that cause diseases in humans and animals. Discovering and characterizing novel microorganisms in this tick species is crucial for identifying potential new pathogens. Using A. americanum ticks collected from Oklahoma, we isolated, cultured and sequenced the entire genome of a previously detected, but uncharacterized, novel Rickettsia species. Triturated A. americanum ticks were used as inoculum to culture the novel Rickettsia species in Vero E6 cells, and qPCR testing confirmed the presence of the new Rickettsia species while ruling out the presence of other tick-borne organisms. The total genome size was 1.17 Mbp consisting of a complete chromosome with a 30.7 % G+C content (GenBank accession CP157197). We predicted 1037 genes, 997 coding gene open reading frames, along with 33 tRNAs, 4 ncRNAs and 3 rRNAs. This genome was most similar to Rickettsia canadensis strain CA410 at 91.1 % identity, based on average nucleotide identity analysis. A maximum-likelihood phylogeny tree, constructed using 636 concatenated core proteins, placed the novel Rickettsia species in a clade with Rickettsia canadensis. We propose the name Rickettsia oklahomensis sp. nov., strain Oklahoma 10, which is available from the Centers for Disease Control and Prevention Rickettsial Isolate Reference Collection (WDCM 1093), Atlanta, GA, USA (CRIRC accession number ROK001).

  PublisherDOI

• Detection of <i>Dirofilaria repens</i> and <i>Mansonella llewellyni</i> in the United States by <i>Wolbachia</i> Surveillance

  Transboundary and Emerging Diseases · 2025-01-01

  articleOpen access

  In mammals, detection of Wolbachia bacteria can be used to diagnose filarial infection, while antibiotic treatment to eliminate Wolbachia can assist in eliminating filarial infections. Because Wolbachia are necessary for survival of several filarioids and closely related to Anaplasma and Ehrlichia , we analyzed Wolbachia DNA amplification by Anaplasma/Ehrlichia qPCR, from 39,526 domestic and wildlife animal blood samples submitted to a diagnostic laboratory between 2017 and 2023. Filarial infection was confirmed by 28S gene amplification, followed by phylogenetic analysis utilizing filarial cytochrome oxidase subunit 1 ( cox1 ), myosin heavy chain ( myoHC ), and 70 kilodalton heat shock protein ( hsp70 ) gene sequencing. Wolbachia DNA was detected in 57 domestic dogs ( Canis familiaris ) and three raccoons ( Procyon lotor ) from 23 states and Puerto Rico. A majority of the Wolbachia sequences from dogs were Dirofilaria immitis ‐associated (89%, 51/57), whereas DNA from other Wolbachia were associated with insects (9%, 5/57) or Dirofilaria repens (2%, 1/57). D. immitis infection was confirmed by 28S filarial PCR for all samples with D. immitis ‐associated Wolbachia available for testing ( n = 41). D. repens infection was confirmed by 28S and cox1 PCR in the dog infected with D. repens ‐associated Wolbachia . This dog was originally imported from Slovakia. The Wolbachia DNA amplified from raccoons most closely aligned with Wolbachia from Mansonella ozzardi (98.9%). 28S filarial, cox1 , myoHC , and hsp70 sequencing did not align with currently available GenBank sequences but did align with Mansonella . Morphologically, microfilariae from additional raccoons were consistent with Mansonella llewellyni . Molecular surveillance for Wolbachia in wildlife and domestic animals has the potential to identify novel filarial species in the United States, including zoonotic species.

  PublisherOA PDFDOI

• Isolation and Characterization of <i>Rickettsia finnyi</i> , Novel Pathogenic Spotted Fever Group <i>Rickettsia</i> in Dogs, United States

  Emerging infectious diseases · 2025-11-01

  articleOpen accessSenior author

  I n 2020, a unique spotted fever group Rickettsia (SFGR), Rickettsia sp.2019-CO-FNY, was identified in 3 clinically ill dogs in the southern and midwestern United States (1).Those dogs exhibited symptoms like those caused by R. rickettsii, the agent responsible for Rocky Mountain spotted fever (RMSF).SFGR are emerging tickborne pathogens infecting dogs and humans.Among tickborne pathogens infecting dogs, SFGR had the highest seroprevalence at 10.4% in the United States during 2004-2010 (2).The Centers for Disease Control and Prevention reported annual SFGR cases in humans in the United States increased substantially from 486 in 2000 to 6,248 in 2017 (3).Despite frequent exposure to SFGR, gaps remain in our understanding of pathogenic Rickettsia spp., disease severity, and tick vectors.In the United States, several SFGR species, including R. parkeri, R. rickettsii, and R. rickettsii subsp.californica, cause disease in humans (4,5).Among those species, R. rickettsii is the most virulent in dogs and humans and can be fatal without early antibiotic intervention (6).In addition to R. rickettsii, other SFGR species have been detected in dogs in the United States, including R. montanensis, R. amblyommatis, and R. parkeri, all of which caused asymptomatic infection (7,8).Until recently, R. rickettsii was the only SFGR known to cause disease in dogs in North America.Dogs with RMSF can demonstrate fever, lethargy, neurologic signs, and generalized or localized pain, like arthropathy (9,10).Clinical signs reported in dogs infected with Rickettsia sp.2019-CO-FNY resembled those seen in RMSF, indicating the existence of additional virulent SFGR in the United States and underscoring the importance of expanded vectorborne disease surveillance for canine and human health.In this study, we cultured and sequenced a novel, pathogenic SFGR, Rickettsia sp.2019-CO-FNY.We identified Rickettsia sp.2019-CO-FNY in 14 additional sick dogs and cultured it from 1 infected dog.On the basis of whole-genome sequencing (WGS) and imaging, we determined that Rickettsia sp.2019-CO-FNY is a new Rickettsia species, which we propose naming Rickettsia finnyi sp.nov., strain 2024-CO-Wats.

  PublisherOA PDFDOI

• First identification of Candidatus Rickettsia andeanae in host-attached Dermacentor variabilis and across a large geographic sampling region, South Carolina, U.S.A.

  Journal of Vector Ecology · 2025-04-29 · 1 citations

  article
  PublisherDOI

• Rapid Increase in Seroprevalence of <i>Borrelia burgdorferi</i> Antibodies among Dogs, Northwestern North Carolina, USA, 2017–20211

  Emerging infectious diseases · 2024-09-25 · 3 citations

  articleOpen access

  We evaluated spatial-temporal risk for Lyme disease in northwestern North Carolina, USA, by using individual-level canine Borrelia burgdorferi seroprevalence data collected during 2017-2021 at routine veterinary screenings for tickborne diseases. Seroprevalence in dogs increased from 2.2% (47/2,130) in 2017 to 11.2% (339/3,033) in 2021. The percentage of incident seropositivity increased from 2.1% (45/2,130) in 2017 to 7.6% (231/3,033) in 2021. Exploratory geographic analyses found canine seroprevalence shifted from clustered (2017, Moran's I = 0.30) to dispersed (2021, Moran's I = -0.20). Elevation, slope, aspect, and forest land cover density were associated with canine seroprevalence within various household buffer regions in 2017. Slope was associated with seroprevalence at the household level in 2021. Results support the use of individual-level canine seroprevalence data for monitoring human risk for Lyme disease. Establishing sentinel veterinary clinics within Lyme disease-emergent communities might promote prevention and control efforts and provide opportunities for educational and behavioral interventions.

  PublisherOA PDFDOI

• Detection of <i>Anaplasma phagocytophilum</i> in an inflammatory pericardial effusion of a dog

  Journal of Veterinary Internal Medicine · 2024-05-04 · 2 citations

  articleOpen access

  An 11-year-old female spayed German Wirehaired Pointer with a 1-week history of lethargy, hyporexia, diarrhea, and coughing presented with pericardial effusion causing cardiac tamponade. An echocardiogram revealed no structural cause for pericardial effusion. The pericardial effusion was an exudate with mixed macrophagic and neutrophilic inflammation. Morulae occasionally were found within neutrophils. The pericardial fluid and blood were qPCR and cPCR positive for Anaplasma phagocytophilum (NC State University, Vector-borne Disease Diagnostic Laboratory, Raleigh, NC). The dog's blood was negative by ELISA (Vetscan Flex4 Rapid Test, Zoetis, Parsippany, NJ) for A. phagocytophilum antibodies at initial presentation and subsequently positive (SNAP4DxPlus, IDEXX, Westbrook, ME) 7 days later. After pericardiocentesis and administration of doxycycline (5 mg/kg PO q12h for 14 days), a repeat echocardiogram performed 1 month later showed no recurrence of pericardial effusion.

  PublisherOA PDFDOI

• Contrasting pathogen prevalence between tick and dog populations at Chornobyl

  Parasites & Vectors · 2024-11-17 · 2 citations

  articleOpen access

  BACKGROUND: The 1986 disaster at the Chornobyl Nuclear Power Plant released massive amounts of radioactive material into the local environment. In addition to radiation, remediation efforts and abandonment of military-industrial complexes contributed to contamination with heavy metals, organics, pesticides and other toxic chemicals. Numerous studies have evaluated the effects of this contamination on the local ecology. However, few studies have reported the effect of this contamination on vector-borne pathogens and their hosts. In this manuscript, we characterize tick-borne pathogen presence at two sample locations within the Chornobyl Exclusion Zone, one at the Nuclear Power Plant (NPP) and another 16 km away in Chornobyl City (CC). METHODS: Ticks and whole-blood samples were collected from free-breeding dogs captured at the NPP and CC. Endpoint PCR and quantitative PCR were used to identify tick species and to assess the presence of specific tick-borne pathogens, including Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Babesia spp., Bartonella spp., Francisella tularensis and general Anaplasmataceae. A droplet digital PCR assay was developed for Babesia canis and A. phagocytophilum to evaluate their presence in dogs from the two populations. Pathogen prevalences between the two sample populations were compared by calculating Z-scores. RESULTS: Ticks were identified as Ixodes ricinus (n = 102) and Dermacentor reticulatus (n = 4). Overall, 56.9% of I. ricinus ticks were positive for at least one pathogen. A significantly higher prevalence of A. phagocytophilum and B. burgdorferi was found in ticks at the NPP (44.0% and 42.0%, respectively) compared to CC (23.1% and 19.2%, respectively). Babesia spp. (including B. canis and B. caballi) were detected in 8.8% ticks at similar proportions for both populations. Interestingly, we found a significantly lower level of A. phagocytophilum in dogs at the NPP (1.8%) than in dogs at CC (11.7%). In total, 24.3% of dogs were positive for B. canis, evenly distributed across the two populations. CONCLUSIONS: The results of this study show contrasting pathogen prevalence in both ticks and dogs at the NPP and CC, which may reflect the differential exposures at the two locations. This work adds an important new component to our understanding of the consequences of prolonged exposure to environmental contamination on the wildlife and ecology within the Chornobyl Exclusion Zone.

  PublisherOA PDFDOI

• Contrasting pathogen prevalence between tick and dog populations at Chornobyl

  UNC Libraries · 2024-12-04

  articleOpen access
  PublisherDOI

• Evaluation of the Veterinary IDEXX SNAP 4Dx Plus Test for the Diagnosis of Lyme Disease in Humans

  Vector-Borne and Zoonotic Diseases · 2024-06-19

  articleOpen access

  Background: Lyme disease, caused by infection with Borrelia burgdorferi, is the most common vector-borne disease in the United States. The standard two-tier testing (STTT) algorithm suffers from low sensitivity, misinterpretation, and long turnaround time, preventing timely detection and treatment. To address these challenges, we hypothesized that the canine point-of-care (PoC) SNAP 4Dx Plus test used to detect Borrelia burgdorferi antibodies could be employed for human diagnosis. Materials and Methods: The SNAP 4Dx Plus testing was conducted in accordance with the manufacturer’s instructions, with results read by manual inspection. All analyses were conducted using R version 4.3.1, and agreement between the PoC assay and the STTT was assessed using kappa statistics with GraphPad software. Results: We included 102 previously-tested human serum samples, of which 19 samples (18.6%) were STTT positive. Compared to the STTT, the SNAP 4Dx Plus test demonstrated a low sensitivity of 0.16 (95% CI 0.03 to 0.40). Conclusion: Overall, our results do not support the use of the SNAP 4Dx Plus LD assay for the diagnosis of human Lyme disease. Differences in antibody concentrations between human and canine samples may partly explain our findings.

  PublisherDOI

• Isolation, Culture, and Genome Analysis of Rickettsia Oklahomensis Sp. Nov., a New Canadensis Group Rickettsia from Amblyomma Americanum Ixodid Ticks

  SSRN Electronic Journal · 2024-01-01

  preprintOpen accessSenior author
  PublisherDOI

Frequent coauthors

• Edward B. Breitschwerdt

  North Carolina State University

  44 shared

• Barbara C. Hegarty

  North Carolina State University

  13 shared

• James M. Wilson

  12 shared

• Adam J. Birkenheuer

  North Carolina State University

  10 shared

• Ricardo G. Maggi

  North Carolina State University

  9 shared

• Ramaswamy Chandrashekar

  IDEXX Laboratories (United States)

  7 shared

• Melissa J. Beall

  IDEXX Laboratories (United States)

  6 shared

• Henry S. Marr

  6 shared

Education

• Ph.D., Comparative Medicine

  North Carolina State University

  2000

• M.S., Comparative Medicine

  University of California, Davis

  1995

• B.S., Animal Science

  University of California, Davis

  1993