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Veterinary medicine and science2025; 11(2); e70272; doi: 10.1002/vms3.70272

Investigation of the Blood Microbiome in Horses With Fever of Unknown Origin.

Abstract: Fever of unknown origin (FUO) without a respiratory component is a frequent clinical presentation in horses. Multiple pathogens, both tick-borne and enteric, can be involved as etiologic agents. An additional potential mechanism is intestinal barrier dysfunction. This case-control study aimed to detect and associate microbial taxa in blood with disease state. Areas known for a high prevalence of tick-borne diseases in humans were chosen to survey horses with FUO, which was defined as fever of 101.5°F or higher with no signs of respiratory illness or other recognisable diseases. Blood samples and clinical parameters were obtained from 52 FUO cases and also from matched controls from the same farms. An additional 23 febrile horses without matched controls were included. Broadly targeted polymerase chain reaction (PCR) amplification directed at conserved sequence regions of bacterial 16S rRNA, parasite 18S rRNA, coronavirus RdRp and parvovirus NS1 was performed, followed by deep sequencing. To control for contamination and identify taxa unique to the cases, metagenomic sequences from the controls were subtracted from those of the cases, and additional targeted molecular testing was performed. Sera were also tested for antibodies to equine coronavirus. Over 60% of cases had intestinal microbial DNA circulating in the blood. Nineteen percent of cases were attributed to infection with Anaplasma phagocytophilum, of which two were subtyped as human-associated strains. A novel Erythroparvovirus was detected in two cases and two controls. Serum titres for equine coronavirus were elevated in some cases but not statistically different overall between the cases and controls. Not all pathogens are expected to circulate in blood, which was the sole focus of this study. The presence of commensal gut microbes in blood of equine FUO cases is consistent with a compromised intestinal barrier, which is highlighted as a direction for future study.
Publication Date: 2025-03-11 PubMed ID: 40065594PubMed Central: PMC11893731DOI: 10.1002/vms3.70272Google Scholar: Lookup
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  • Journal Article
  • Research Support
  • U.S. Gov't
  • P.H.S.
  • Research Support
  • U.S. Gov't
  • Non-P.H.S.

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research is a case-control study that investigated the presence and relationship of microbial taxa in the blood of horses suffering from fever of unknown origin (FUO). The study findings suggest that FUO cases are often associated with intestinal microbial DNA in the blood, implying possible intestinal barrier dysfunction.

Objectives of the Study

  • The research aimed to detect and associate specific microbial taxa in the blood of horses with a disease (FUO) that exhibits no respiratory issues or other recognizable diseases.

Methods

  • The areas chosen for the investigation were known for a high prevalence of tick-borne diseases in humans.
  • They sampled blood and acquired clinical parameters from 52 FUO cases and matching controls from the same farms. An additional 23 febrile horses without matched controls were also included.
  • The methodology involved a broadly targeted polymerase chain reaction (PCR) amplification focussing on conserved sequence regions of bacterial 16S rRNA, parasite 18S rRNA, coronavirus RdRp, and parvovirus NS1. This was followed by deep sequencing.
  • To establish taxa unique to the cases and control contamination, they subtracted metagenomic sequences from the controls from those of the cases. Targeted molecular testing was also done.
  • Additionally, they tested horse sera for antibodies to equine coronavirus.

Results

  • Over 60% of FUO cases exhibited intestinal microbial DNA circulation in the blood, suggesting a possible dysfunctional intestinal barrier.
  • Nineteen percent of these cases were attributed to infection by Anaplasma phagocytophilum, with two subtyped as human-associated strains.
  • A novel Erythroparvovirus was detected in two cases and the matching controls.
  • The study found elevated serum titres for equine coronavirus in some cases, but there was no statistical difference overall between the cases and controls.

Conclusions

  • The study concluded that the presence of commensal gut microbes in the bloodstream of equine FUO cases could be indicative of a compromised intestinal barrier, warranting further studies on the role of the intestinal barrier in FUO in horses.
  • The research also concluded that not all pathogens linked to FUO would be expected to circulate in the blood.

Cite This Article

APA
Sun Y, Yu YT, Castillo XO, Anderson R, Wang M, Sun Q, Tallmadge R, Sams K, Reboul G, Zehr J, Brown J, Wang X, Marra N, Stanhope B, Grenier J, Pusterla N, Divers T, Mittel L, Goodman LB. (2025). Investigation of the Blood Microbiome in Horses With Fever of Unknown Origin. Vet Med Sci, 11(2), e70272. https://doi.org/10.1002/vms3.70272

Publication

ISSN: 2053-1095
NlmUniqueID: 101678837
Country: England
Language: English
Volume: 11
Issue: 2
Pages: e70272

Researcher Affiliations

Sun, Yining
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Yu, Y Tina
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Castillo, Ximena Olarte
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Anderson, Renee
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Wang, Minghui
  • Center for Biotechnology, Cornell University, Ithaca, New York, USA.
Sun, Qi
  • Center for Biotechnology, Cornell University, Ithaca, New York, USA.
Tallmadge, Rebecca
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Sams, Kelly
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Reboul, Guillaume
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Zehr, Jordan
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Brown, Joel
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Wang, Xiyu
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Marra, Nicholas
  • Division of Science, Mathematics, and Technology, Governors State University, University Park, Illinois, USA.
Stanhope, Bryce
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Grenier, Jennifer
  • Center for Biotechnology, Cornell University, Ithaca, New York, USA.
Pusterla, Nicola
  • School of Veterinary Medicine, University of California, Davis, California, USA.
Divers, Thomas
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Mittel, Linda
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
Goodman, Laura B
  • College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
  • School of Veterinary Medicine, University of California, Davis, California, USA.

MeSH Terms

  • Horses
  • Animals
  • Horse Diseases / microbiology
  • Horse Diseases / blood
  • Case-Control Studies
  • Fever of Unknown Origin / veterinary
  • Fever of Unknown Origin / microbiology
  • Fever of Unknown Origin / blood
  • Male
  • Female
  • Microbiota

Grant Funding

  • 1U18FD006993 / US Food and Drug Administration's Veterinary Laboratory Investigation and Response Network
  • U18 FD006716 / FDA HHS
  • W81XWH-22-1-0891 / Department of Defense
  • 1U18FD006716 / US Food and Drug Administration's Veterinary Laboratory Investigation and Response Network
  • U18 FD006993 / FDA HHS
  • Harry M. Zweig Memorial Fund for Equine Research

Conflict of Interest Statement

The authors declare no conflicts of interest.

References

This article includes 89 references
  1. Al‐Khedery B, Barbet AF. Comparative Genomics Identifies a Potential Marker of Human‐Virulent Anaplasma phagocytophilum. Pathogens 2014 3(1):25-35.
    doi: 10.3390/pathogens3010025pmc: PMC4235736pubmed: 25437606google scholar: lookup
  2. Allison AB, Kohler DJ, Fox KA. Frequent Cross‐Species Transmission of Parvoviruses Among Diverse Carnivore Hosts. Journal of Virology 2013 87(4):2342-2347.
    doi: 10.1128/JVI.02428-12pmc: PMC3571474pubmed: 23221559google scholar: lookup
  3. Atif FA. Anaplasma marginale and Anaplasma phagocytophilum: Rickettsiales Pathogens of Veterinary and Public Health Significance. Parasitology Research 2015 114(11):3941-3957.
    doi: 10.1007/s00436-015-4698-2pubmed: 26346451google scholar: lookup
  4. Barbet AF, Al‐Khedery B, Stuen S, Granquist EG, Felsheim RF, Munderloh UG. An Emerging Tick‐Borne Disease of Humans Is Caused by a Subset of Strains With Conserved Genome Structure. Pathogens 2013 2(3):544-555.
    doi: 10.3390/pathogens2030544pmc: PMC4235699pubmed: 25437207google scholar: lookup
  5. Beekman JM, Reischl J, Henderson D. Recovery of Microarray‐Quality RNA From Frozen EDTA Blood Samples. Journal of Pharmacological and Toxicological Methods 2009 59(1):44-49.
    doi: 10.1016/j.vascn.2008.10.003pubmed: 19028589google scholar: lookup
  6. Belongia EA. Epidemiology and Impact of Coinfections Acquired From Ixodes Ticks. Vector Borne and Zoonotic Diseases (Larchmont, New York) 2002 2(4):265-273.
    doi: 10.1089/153036602321653851pubmed: 12804168google scholar: lookup
  7. Benítez‐Páez A, Álvarez M, Belda‐Ferre P, Rubido S, Mira A, Tomás I. Detection of Transient Bacteraemia Following Dental Extractions by 16S rDNA Pyrosequencing: A Pilot Study. PLoS ONE 2013 8(3):e57782.
  8. Bernard‐Raichon L, Venzon M, Klein J. Gut Microbiome Dysbiosis in Antibiotic‐Treated COVID‐19 Patients Is Associated With Microbial Translocation and Bacteremia. Nature Communications 2022 13(1):5926.
    doi: 10.1038/s41467-022-33395-6pmc: PMC9626559pubmed: 36319618google scholar: lookup
  9. Butler CM, Nijhof AM, Jongejan F, van der Kolk JH. Anaplasma phagocytophilum Infection in Horses in the Netherlands. The Veterinary Record 2008 162(7):216-217.
    doi: 10.1136/vr.162.7.216pubmed: 18281631google scholar: lookup
  10. Callahan BJ, McMurdie PJ, Rosen MJ, Han AW, Johnson AJ, Holmes SP. DADA2: High‐Resolution Sample Inference From Illumina Amplicon Data. Nature Methods 2016 13(7):581-583.
    doi: 10.1038/nmeth.3869pmc: PMC4927377pubmed: 27214047google scholar: lookup
  11. Capuco A, Urits I, Hasoon J. Current Perspectives on Gut Microbiome Dysbiosis and Depression. Advances in Therapy 2020 37(4):1328-1346.
    doi: 10.1007/s12325-020-01272-7pmc: PMC7140737pubmed: 32130662google scholar: lookup
  12. Castillo DJ, Rifkin RF, Cowan DA, Potgieter M. The Healthy Human Blood Microbiome: Fact or Fiction?. Frontiers in Cellular and Infection Microbiology 2019 9:148.
    doi: 10.3389/fcimb.2019.00148pmc: PMC6519389pubmed: 31139578google scholar: lookup
  13. Cerar T, Strle F, Stupica D. Differences in Genotype, Clinical Features, and Inflammatory Potential of Borrelia burgdorferi Sensu Stricto Strains From Europe and the United States. Emerging Infectious Diseases 2016 22(5):818-827.
    doi: 10.3201/eid2205.151806pmc: PMC4861522pubmed: 27088349google scholar: lookup
  14. Chen H, Ma Y, Liu Z. Circulating Microbiome DNA: An Emerging Paradigm for Cancer Liquid Biopsy. Cancer Letters 2021 521:82-87.
    doi: 10.1016/j.canlet.2021.08.036pubmed: 34461180google scholar: lookup
  15. Clarridge JE 3rd. Impact of 16S rRNA Gene Sequence Analysis for Identification of Bacteria on Clinical Microbiology and Infectious Diseases. Clinical Microbiology Reviews 2004 17(4):840-862.
  16. Coker OO, Dai Z, Nie Y. Mucosal Microbiome Dysbiosis in Gastric Carcinogenesis. Gut 2018 67(6):1024-1032.
    doi: 10.1136/gutjnl-2017-314281pmc: PMC5969346pubmed: 28765474google scholar: lookup
  17. Damgaard C, Magnussen K, Enevold C. Viable Bacteria Associated With Red Blood Cells and Plasma in Freshly Drawn Blood Donations. PLoS ONE 2015 10(3):e0120826.
  18. Davis NM, Proctor DM, Holmes SP, Relman DA, Callahan BJ. Simple Statistical Identification and Removal of Contaminant Sequences in Marker‐Gene and Metagenomics Data. Microbiome 2018 6(1):226.
    doi: 10.1186/s40168-018-0605-2pmc: PMC6298009pubmed: 30558668google scholar: lookup
  19. Divers TJ, Gardner RB, Madigan JE. Borrelia burgdorferi Infection and Lyme Disease in North American Horses: A Consensus Statement. Journal of Veterinary Internal Medicine 2018 32(2):617-632.
    doi: 10.1111/jvim.15042pmc: PMC5866975pubmed: 29469222google scholar: lookup
  20. Divers TJ, Tennant BC, Kumar A. New Parvovirus Associated With Serum Hepatitis in Horses After Inoculation of Common Biological Product. Emerging Infectious Diseases 2018 24(2):303-310.
    doi: 10.3201/eid2402.171031pmc: PMC5782890pubmed: 29350162google scholar: lookup
  21. Dubnau D, Smith I, Morell P, Marmur J. Gene Conservation in Bacillus Species. I. Conserved Genetic and Nucleic Acid Base Sequence Homologies. Proceedings of the National Academy of Sciences of the United States of America 1965 54(2):491-498.
    doi: 10.1073/pnas.54.2.491pmc: PMC219694pubmed: 4956287google scholar: lookup
  22. Dunning Hotopp JC, Lin M, Madupu R. Comparative Genomics of Emerging Human Ehrlichiosis Agents. PLoS Genetics 2006 2(2):e21.
  23. Fleshman AC, Foster E, Maes SE, Eisen RJ. Reported County‐Level Distribution of Seven Human Pathogens Detected in Host‐Seeking Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the Contiguous United States. Journal of Medical Entomology 2022 59(4):1328-1335.
    doi: 10.1093/jme/tjac049pubmed: 35583265google scholar: lookup
  24. François S, Filloux D, Roumagnac P. Discovery of Parvovirus‐Related Sequences in an Unexpected Broad Range of Animals. Scientific Reports 2016 6:30880.
    doi: 10.1038/srep30880pmc: PMC5013282pubmed: 27600734google scholar: lookup
  25. Glassing A, Dowd SE, Galandiuk S, Davis B, Chiodini RJ. Inherent Bacterial DNA Contamination of Extraction and Sequencing Reagents May Affect Interpretation of Microbiota in Low Bacterial Biomass Samples. Gut Pathogens 2016 8:24.
    doi: 10.1186/s13099-016-0103-7pmc: PMC4882852pubmed: 27239228google scholar: lookup
  26. Goodman JL, Nelson C, Vitale B. Direct Cultivation of the Causative Agent of Human Granulocytic Ehrlichiosis. New England Journal of Medicine 1996 334(4):209-215.
    doi: 10.1056/NEJM199601253340401pubmed: 8531996google scholar: lookup
  27. Gosiewski T, Ludwig‐Galezowska AH, Huminska K. Comprehensive Detection and Identification of Bacterial DNA in the Blood of Patients With Sepsis and Healthy Volunteers Using Next‐Generation Sequencing Method—The Observation of DNAemia. European Journal of Clinical Microbiology & Infectious Diseases 2017 36(2):329-336.
    doi: 10.1007/s10096-016-2805-7pmc: PMC5253159pubmed: 27771780google scholar: lookup
  28. Grobman M, Cohn L, Knapp S, Bryan JN, Reinero C. (18) F‐FDG‐PET/CT as Adjunctive Diagnostic Modalities in Canine Fever of Unknown Origin. Veterinary Radiology & Ultrasound 2018 59(1):107-115.
    doi: 10.1111/vru.12562pubmed: 28925085google scholar: lookup
  29. Haas BJ, Gevers D, Earl AM. Chimeric 16S rRNA Sequence Formation and Detection in Sanger and 454‐Pyrosequenced PCR Amplicons. Genome Research 2011 21(3):494-504.
    doi: 10.1101/gr.112730.110pmc: PMC3044863pubmed: 21212162google scholar: lookup
  30. Harris DJ. Naming No Names: Comments on the Taxonomy of Small Piroplasmids in Canids. Parasites & Vectors 2016 9(1):289.
    doi: 10.1186/s13071-016-1567-5pmc: PMC4872352pubmed: 27193588google scholar: lookup
  31. Hersh MH, Ostfeld RS, McHenry DJ. Co‐Infection of Blacklegged Ticks With Babesia microti and Borrelia burgdorferi Is Higher Than Expected and Acquired From Small Mammal Hosts. PLoS ONE 2014 9(6):e99348.
  32. Hugenholtz P, Tyson GW. Microbiology: Metagenomics. Nature 2008 455(7212):481-483.
    doi: 10.1038/455481apubmed: 18818648google scholar: lookup
  33. Huhn C, Winter C, Wolfsperger T. Analysis of the Population Structure of Anaplasma phagocytophilum Using Multilocus Sequence Typing. PLoS ONE 2014 9(4):e93725.
  34. Huse SM, Ye Y, Zhou Y, Fodor AA. A Core Human Microbiome as Viewed Through 16S rRNA Sequence Clusters. PLoS ONE 2012 7(6):e34242.
  35. Janda JM, Abbott SL. 16S rRNA Gene Sequencing for Bacterial Identification in the Diagnostic Laboratory: Pluses, Perils, and Pitfalls. Journal of Clinical Microbiology 2007 45(9):2761-2764.
    doi: 10.1128/JCM.01228-07pmc: PMC2045242pubmed: 17626177google scholar: lookup
  36. Jolley KA, Bray JE, Maiden MCJ. Open‐Access Bacterial Population Genomics: BIGSdb Software, the PubMLST.Org Website and Their Applications. Wellcome Open Research 2018 3:124.
  37. Jung C, Hugot JP, Barreau F. Peyer's Patches: The Immune Sensors of the Intestine. International Journal of Inflammation 2010 2010:823710.
    doi: 10.4061/2010/823710pmc: PMC3004000pubmed: 21188221google scholar: lookup
  38. Kalantar KL, Carvalho T, de Bourcy CFA. IDseq – An Open Source Cloud‐Based Pipeline and Analysis Service for Metagenomic Pathogen Detection and Monitoring. GigaScience 2020 9(10):giaa111.
    doi: 10.1093/gigascience/giaa111pmc: PMC7566497pubmed: 33057676google scholar: lookup
  39. Kambayashi Y, Bannai H, Tsujimura K, Hirama A, Ohta M, Nemoto M. Outbreak of Equine Coronavirus Infection Among Riding Horses in Tokyo, Japan. Comparative Immunology, Microbiology and Infectious Diseases 2021 77:101668.
    doi: 10.1016/j.cimid.2021.101668pubmed: 34004508google scholar: lookup
  40. Karnik M, Kumar A, Shabir Khaki A, Mirza H. First Molecular Detection of Babesia gibsoni in a Horse. Equine Veterinary Education 2022 34(3):e116-e119.
    doi: 10.1111/eve.13555google scholar: lookup
  41. Kolbert CP, Bruinsma ES, Abdulkarim AS. Characterization of an Immunoreactive Protein From the Agent of Human Granulocytic Ehrlichiosis. Journal of Clinical Microbiology 1997 35(5):1172-1178.
  42. Kooijman LJ, James K, Mapes SM, Theelen MJP, Pusterla N. Seroprevalence and Risk Factors for Infection With Equine Coronavirus in Healthy Horses in the USA. Veterinary Journal (London, England: 1997) 2017 220:91-94.
    doi: 10.1016/j.tvjl.2017.01.007pmc: PMC7110631pubmed: 28190504google scholar: lookup
  43. Kowarsky M, Camunas-Soler J, Kertesz M. Numerous Uncharacterized and Highly Divergent Microbes Which Colonize Humans Are Revealed by Circulating Cell‐Free DNA. Proceedings of the National Academy of Sciences of the United States of America 2017 114(36):9623-9628.
    doi: 10.1073/pnas.1707009114pmc: PMC5594678pubmed: 28830999google scholar: lookup
  44. Kuczynski J, Stombaugh J, Walters WA, González A, Caporaso JG, Knight R. Using QIIME to Analyze 16S rRNA Gene Sequences From Microbial Communities. Current Protocols in Bioinformatics 2011 Chapter 10:10.7.1-10.7.20.
  45. Langenwalder DB, Schmidt S, Silaghi C. The Absence of the Drhm Gene Is Not a Marker for Human‐Pathogenicity in European Anaplasma phagocytophilum Strains. Parasites Vectors 2020 13(1):238.
    doi: 10.1186/s13071-020-04116-zpmc: PMC7206706pubmed: 32381072google scholar: lookup
  46. Li SK, Leung RKK, Guo HX. Detection and Identification of Plasma Bacterial and Viral Elements in HIV/AIDS Patients in Comparison to Healthy Adults. Clinical Microbiology and Infection 2012 18(11):1126-1133.
  47. Liu L, Liu W, Zheng Y. A Preliminary Study on Serological Assay for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) in 238 Admitted Hospital Patients. Microbes and Infection 2020 22(4-5):206-211.
  48. Liu NN, Ma Q, Ge Y. Microbiome Dysbiosis in Lung Cancer: From Composition to Therapy. NPJ Precision Oncology 2020 4(1):33.
    doi: 10.1038/s41698-020-00138-zpmc: PMC7730185pubmed: 33303906google scholar: lookup
  49. Magnarelli LA, Ijdo JW, Van Andel AE, Wu C, Padula SJ, Fikrig E. Serologic Confirmation of Ehrlichia equi and Borrelia burgdorferi Infections in Horses From the Northeastern United States. Journal of the American Veterinary Medical Association 2000 217(7):1045-1050.
    doi: 10.2460/javma.2000.217.1045pubmed: 11019714google scholar: lookup
  50. Mair TS, Taylor FG, Pinsent PJ. Fever of Unknown Origin in the Horse: A Review of 63 Cases. Equine Veterinary Journal 1989 21(4):260-265.
  51. Majazki J, Wüppenhorst N, Hartelt K, Birtles R, von Loewenich FD. Anaplasma phagocytophilum Strains From Voles and Shrews Exhibit Specific ankA Gene Sequences. BMC Veterinary Research 2013 9:235.
    doi: 10.1186/1746-6148-9-235pmc: PMC4220824pubmed: 24283328google scholar: lookup
  52. Mande SS, Mohammed MH, Ghosh TS. Classification of Metagenomic Sequences: Methods and Challenges. Briefings in Bioinformatics 2012 13(6):669-681.
    doi: 10.1093/bib/bbs054pubmed: 22962338google scholar: lookup
  53. McDonald D, Ackermann G, Khailova L. Extreme Dysbiosis of the Microbiome in Critical Illness. mSphere 2016 1(4):e00199-e00216.
    doi: 10.1128/mSphere.00199-16pmc: PMC5007431pubmed: 27602409google scholar: lookup
  54. Minamimoto R. Optimal Use of the FDG‐PET/CT in the Diagnostic Process of Fever of Unknown Origin (FUO): A Comprehensive Review. Japanese Journal of Radiology 2022 40(11):1121-1137.
    doi: 10.1007/s11604-022-01306-wpmc: PMC9616755pubmed: 35781177google scholar: lookup
  55. Miszczak F, Tesson V, Kin N. First Detection of Equine Coronavirus (ECoV) in Europe. Veterinary Microbiology 2014 171(1-2):206-209.
  56. Munderloh UG, Jauron SD, Fingerle V. Invasion and Intracellular Development of the Human Granulocytic Ehrlichiosis Agent in Tick Cell Culture. Journal of Clinical Microbiology 1999 37(8):2518-2524.
  57. Nikkari S, McLaughlin IJ, Bi W, Dodge DE, Relman DA. Does Blood of Healthy Subjects Contain Bacterial Ribosomal DNA?. Journal of Clinical Microbiology 2001 39(5):1956-1959.
  58. Nurk S, Meleshko D, Korobeynikov A, Pevzner PA. metaSPAdes: A New Versatile Metagenomic Assembler. Genome Research 2017 27(5):824-834.
    doi: 10.1101/gr.213959.116pmc: PMC5411777pubmed: 28298430google scholar: lookup
  59. Pace EJ, O'Reilly M. Tickborne Diseases: Diagnosis and Management. American Family Physician 2020 101(9):530-540.
    pubmed: 32352736
  60. Païssé S, Valle C, Servant F. Comprehensive Description of Blood Microbiome From Healthy Donors Assessed by 16S Targeted Metagenomic Sequencing. Transfusion 2016 56(5):1138-1147.
    doi: 10.1111/trf.13477pubmed: 26865079google scholar: lookup
  61. Poore GD, Kopylova E, Zhu Q. Microbiome Analyses of Blood and Tissues Suggest Cancer Diagnostic Approach. Nature 2020 579(7800):567-574.
    doi: 10.1038/s41586-020-2095-1pmc: PMC7500457pubmed: 32214244google scholar: lookup
  62. Potgieter M, Bester J, Kell DB, Pretorius E. The Dormant Blood Microbiome in Chronic, Inflammatory Diseases. FEMS Microbiology Reviews 2015 39(4):567-591.
    doi: 10.1093/femsre/fuv013pmc: PMC4487407pubmed: 25940667google scholar: lookup
  63. Pusterla N, Mapes S, Wademan C. Emerging Outbreaks Associated With Equine Coronavirus in Adult Horses. Veterinary Microbiology 2013 162(1):228-231.
  64. Pusterla N, Vin R, Leutenegger CM, Mittel LD, Divers TJ. Enteric Coronavirus Infection in Adult Horses. Veterinary Journal (London, England: 1997) 2018 231:13-18.
    doi: 10.1016/j.tvjl.2017.11.004pmc: PMC7110460pubmed: 29429482google scholar: lookup
  65. Quan PL, Firth C, Street C. Identification of a Severe Acute Respiratory Syndrome Coronavirus‐Like Virus in a Leaf‐Nosed Bat in Nigeria. MBio 2010 1(4):e00208-e00210.
    doi: 10.1128/mBio.00208-10pmc: PMC2975989pubmed: 21063474google scholar: lookup
  66. Quast C, Pruesse E, Yilmaz P. The SILVA Ribosomal RNA Gene Database Project: Improved Data Processing and Web‐Based Tools. Nucleic Acids Research 2013 41(Database issue):D590-D596.
    doi: 10.1093/nar/gks1219pmc: PMC3531112pubmed: 23193283google scholar: lookup
  67. Reye AL, Hübschen JM, Sausy A, Muller CP. Prevalence and Seasonality of Tick‐Borne Pathogens in Questing Ixodes ricinus Ticks From Luxembourg. Applied and Environmental Microbiology 2010 76(9):2923-2931.
    doi: 10.1128/AEM.03061-09pmc: PMC2863427pubmed: 20228110google scholar: lookup
  68. Rikihisa Y. Cross‐Reacting Antigens Between Neorickettsia helminthoeca and Ehrlichia Species, Shown by Immunofluorescence and Western Immunoblotting. Journal of Clinical Microbiology 1991 29(9):2024-2029.
  69. Rochlin I, Toledo A. Emerging Tick‐Borne Pathogens of Public Health Importance: A Mini‐Review. Journal of Medical Microbiology 2020 69(6):781-791.
    doi: 10.1099/jmm.0.001206pmc: PMC7451033pubmed: 32478654google scholar: lookup
  70. Russell A, Shost N, Burch M. Serological and Molecular Detection of Anaplasma Spp. in Blood From Healthy Horses: A Preliminary Study of Horses in East Texas. Journal of Equine Veterinary Science 2021 106:103757.
    doi: 10.1016/j.jevs.2021.103757pubmed: 34670700google scholar: lookup
  71. Salter SJ, Cox MJ, Turek EM. Reagent and Laboratory Contamination Can Critically Impact Sequence‐Based Microbiome Analyses. BMC Biology 2014 12:87.
    doi: 10.1186/s12915-014-0087-zpmc: PMC4228153pubmed: 25387460google scholar: lookup
  72. Sang C, Yang M, Xu B. Tick Distribution and Detection of Babesia and Theileria Species in Eastern and Southern Kazakhstan. Ticks and Tick‐Borne Diseases 2021 12(6):101817.
    doi: 10.1016/j.ttbdis.2021.101817pubmed: 34560427google scholar: lookup
  73. Scharf W, Schauer S, Freyburger F. Distinct Host Species Correlate With Anaplasma phagocytophilum ankA Gene Clusters. Journal of Clinical Microbiology 2011 49(3):790-796.
    doi: 10.1128/JCM.02051-10pmc: PMC3067700pubmed: 21177886google scholar: lookup
  74. Schlesselman JJ. Monographs in Epidemiology and Biostatistics. 1982 Case‐Control Studies: Design, Conduct, Analysis.
  75. Shabihkhani M, Lucey GM, Wei B. The Procurement, Storage, and Quality Assurance of Frozen Blood and Tissue Biospecimens in Pathology, Biorepository, and Biobank Settings. Clinical Biochemistry 2014 47(4-5):258-266.
  76. Sievers F, Wilm A, Dineen D. Fast, Scalable Generation of High‐Quality Protein Multiple Sequence Alignments Using Clustal Omega. Molecular Systems Biology 2011 7:539.
    doi: 10.1038/msb.2011.75pmc: PMC3261699pubmed: 21988835google scholar: lookup
  77. Stewart AS, Pratt-Phillips S, Gonzalez LM. Alterations in Intestinal Permeability: The Role of the “Leaky Gut” in Health and Disease. Journal of Equine Veterinary Science 2017 52:10-22.
    doi: 10.1016/j.jevs.2017.02.009pmc: PMC6467570pubmed: 31000910google scholar: lookup
  78. Subbiah M, Thirumalapura N, Thompson D, Kuchipudi SV, Jayarao B, Tewari D. Detection of Anaplasma phagocytophilum in Horses With Suspected Tick‐Borne Disease in Northeastern United States by Metagenomic Sequencing. Frontiers in Veterinary Science 2021 8:673193.
    doi: 10.3389/fvets.2021.673193pmc: PMC8219919pubmed: 34179165google scholar: lookup
  79. Swanson SJ, Neitzel D, Reed KD, Belongia EA. Coinfections Acquired From Ixodes Ticks. Clinical Microbiology Reviews 2006 19(4):708-727.
    doi: 10.1128/CMR.00011-06pmc: PMC1592693pubmed: 17041141google scholar: lookup
  80. Tamura K, Stecher G, Kumar S. MEGA11: Molecular Evolutionary Genetics Analysis Version 11. Molecular Biology and Evolution 2021 38(7):3022-3027.
    doi: 10.1093/molbev/msab120pmc: PMC8233496pubmed: 33892491google scholar: lookup
  81. Tan CCS, Ko KKK, Chen H. No Evidence for a Common Blood Microbiome Based on a Population Study of 9,770 Healthy Humans. Nature Microbiology 2023 8(5):973-985.
    doi: 10.1038/s41564-023-01350-wpmc: PMC10159858pubmed: 36997797google scholar: lookup
  82. Theel ES. The Past, Present, and (Possible) Future of Serologic Testing for Lyme Disease. Journal of Clinical Microbiology 2016 54(5):1191-1196.
    doi: 10.1128/JCM.03394-15pmc: PMC4844714pubmed: 26865690google scholar: lookup
  83. Tirosh-Levy S, Gottlieb Y, Fry LM, Knowles DP, Steinman A. Twenty Years of Equine Piroplasmosis Research: Global Distribution, Molecular Diagnosis, and Phylogeny. Pathogens (Basel, Switzerland) 2020 9(11):926.
    doi: 10.3390/pathogens9110926pmc: PMC7695325pubmed: 33171698google scholar: lookup
  84. Tong X, Yu X, Du Y. Peripheral Blood Microbiome Analysis via Noninvasive Prenatal Testing Reveals the Complexity of Circulating Microbial Cell‐Free DNA. Microbiology Spectrum 2022 10(3):e0041422.
    doi: 10.1128/spectrum.00414-22pmc: PMC9241824pubmed: 35608350google scholar: lookup
  85. Venter JC, Remington K, Heidelberg JF. Environmental Genome Shotgun Sequencing of the Sargasso Sea. Science (New York, New York) 2004 304(5667):66-74.
    doi: 10.1126/science.1093857pubmed: 15001713google scholar: lookup
  86. Watanabe S, Masangkay JS, Nagata N. Bat Coronaviruses and Experimental Infection of Bats, the Philippines. Emerging Infectious Diseases 2010 16(8):1217-1223.
    doi: 10.3201/eid1608.100208pmc: PMC3298303pubmed: 20678314google scholar: lookup
  87. Yu YT, Olarte Castillo X, Reboul G. Genome Sequence of Equine Erythroparvovirus 1, Identified in the USA. Microbiology Resource Announcements .
    doi: 10.1128/mra.00897-24pmc: PMC11895488pubmed: 39878505google scholar: lookup
  88. Zhang J, Guy JS, Snijder EJ, Denniston DA, Timoney PJ, Balasuriya UBR. Genomic Characterization of Equine Coronavirus. Virology 2007 369(1):92-104.
    doi: 10.1016/j.virol.2007.06.035pmc: PMC7103287pubmed: 17706262google scholar: lookup
  89. Zhang P, Zhang ZH, Liang J. Metagenomic Next‐Generation Sequencing for the Diagnosis of Fever of Unknown Origin in Pediatric Patients With Hematological Malignancy. Clinica Chimica Acta; International Journal of Clinical Chemistry 2022 537:133-139.
    doi: 10.1016/j.cca.2022.10.008pubmed: 36283493google scholar: lookup