Detection and Genotyping of Coxiella burnetii and Coxiella-Like Bacteria in Horses in South Korea

• Published in: PloS one 2016-05, Vol.11 (5), p.e0156710-e0156710
• Main Authors: Seo, Min-Goo, Lee, Seung-Hun, VanBik, Dorene, Ouh, In-Ohk, Yun, Sun-Hee, Choi, Eunsang, Park, Yong-Soo, Lee, Sang-Eun, Kim, Jong Wan, Cho, Gil-Jae, Kwon, Oh-Deog, Kwak, Dongmi
• Format: Article
• Language: English
• Subjects: Abortion; Animals; Antibodies, Bacterial - blood; Arachnids; Bacteria; Base Sequence; Biology and Life Sciences; Bovidae; Control programs; Coxiella burnetii; Coxiella burnetii - classification; Coxiella burnetii - genetics; Coxiella burnetii - immunology; Deoxyribonucleic acid; DNA; DNA, Bacterial - genetics; Domestic animals; Enzyme-Linked Immunosorbent Assay; Farms; Fetuses; Fever; Genetic aspects; Genotypes; Genotyping; Health aspects; Horses; Horses - microbiology; Host-bacteria relationships; Identification and classification; Infections; Inhalation; Ixodidae; Laboratory animals; Medicine and Health Sciences; Parasitic diseases; People and places; Public health; Q Fever - epidemiology; Q Fever - microbiology; Q Fever - transmission; Quarantine; Republic of Korea - epidemiology; Research and Analysis Methods; Respiration; Rickettsia; Rickettsiae; RNA, Ribosomal, 16S - genetics; rRNA 16S; Sample size; Sequence Analysis, DNA; Studies; Tick-Borne Diseases - microbiology; Tick-Borne Diseases - transmission; Tick-Borne Diseases - veterinary; Ticks; Veterinary colleges; Veterinary medicine; Zoonoses
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0156710

Coxiella burnetii and Coxiella-like bacteria (CLB) are genetically and ecologically distinct despite some genetic similarities. Furthermore, CLB are exceptionally diverse and widespread in ticks, but rarely detected in domestic animals. Since Coxiella bacteria can be transmitted from infected horses by inhalation or by coming in contact with ticks during activities such as horseback riding, it is necessary to study their prevalence. To the best of our knowledge, this is the first large-scale nationwide investigation of the prevalence of C. burnetii and CLB among horses reared in South Korea. Of 816 blood samples collected between 2007 and 2013, 11 (1.3%) were identified as C. burnetii by ELISA, and six (0.7%) as CLB by 16S rRNA sequencing. While a sequence from Jeju Island was similar (97.9-100%) to those within clade B, five sequences obtained from the northern region were categorized into a new clade, indicating the sequence diversity of the genus Coxiella. Studies until date had detected CLB only in ticks; here, we describe their detection in mammals. Given their zoonotic potential, strategic monitoring and appropriate control programs for Coxiella species need to be established.