Department of Avian Science, University of California, Davis, California, United States of America.
Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, California, United States of America.
PLoS One. 2021 Oct 13;16(10):e0258500. doi: 10.1371/journal.pone.0258500. eCollection 2021.
Chlamydial infections, caused by a group of obligate, intracellular, gram-negative bacteria, have health implications for animals and humans. Due to their highly infectious nature and zoonotic potential, staff at wildlife rehabilitation centers should be educated on the clinical manifestations, prevalence, and risk factors associated with Chlamydia spp. infections in raptors. The objectives of this study were to document the prevalence of chlamydial DNA shedding and anti-chlamydial antibodies in raptors admitted to five wildlife rehabilitation centers in California over a one-year period. Chlamydial prevalence was estimated in raptors for each center and potential risk factors associated with infection were evaluated, including location, species, season, and age class. Plasma samples and conjunctiva/choana/cloaca swabs were collected for serology and qPCR from a subset of 263 birds of prey, representing 18 species. Serologic assays identified both anti-C. buteonis IgM and anti-chlamydial IgY antibodies. Chlamydial DNA and anti-chlamydial antibodies were detected in 4.18% (11/263) and 3.14% (6/191) of patients, respectively. Chamydial DNA was identified in raptors from the families Accipitridae and Strigidae while anti-C.buteonis IgM was identified in birds identified in Accipitridae, Falconidae, Strigidae, and Cathartidae. Two of the chlamydial DNA positive birds (one Swainson's hawk (Buteo swainsoni) and one red-tailed hawk (Buteo jamaicensis)) were necropsied, and tissues were collected for culture. Sequencing of the cultured elementary bodies revealed a chlamydial DNA sequence with 99.97% average nucleotide identity to the recently described Chlamydia buteonis. Spatial clusters of seropositive raptors and raptors positive for chlamydial DNA were detected in northern California. Infections were most prevalent during the winter season. Furthermore, while the proportion of raptors testing positive for chlamydial DNA was similar across age classes, seroprevalence was highest in adults. This study questions the current knowledge on C. buteonis host range and highlights the importance of further studies to evaluate the diversity and epidemiology of Chlamydia spp. infecting raptor populations.
衣原体感染由一组专性、细胞内、革兰氏阴性细菌引起，对动物和人类的健康都有影响。由于其高度传染性和人畜共患的潜力，野生动物康复中心的工作人员应该了解猛禽中衣原体 spp.感染的临床表现、流行率和危险因素。本研究的目的是记录在加利福尼亚州的五个野生动物康复中心接受治疗的猛禽中，衣原体 DNA 脱落和抗衣原体抗体的流行率。估计了每个中心的衣原体流行率，并评估了与感染相关的潜在危险因素，包括地点、物种、季节和年龄组。从 263 只猛禽中采集了一小部分（代表 18 个物种）的血浆样本和结膜/鼻道/泄殖腔拭子，用于血清学和 qPCR。血清学检测鉴定出抗衣原体 IgM 和抗衣原体 IgY 抗体。在 4.18%（11/263）和 3.14%（6/191）的患者中分别检测到衣原体 DNA 和抗衣原体抗体。在 Accipitridae 和 Strigidae 科的猛禽中发现了衣原体 DNA，而在 Accipitridae、Falconidae、Strigidae 和 Cathartidae 科的鸟类中发现了抗-C.buteonis IgM。两只衣原体 DNA 阳性的鸟类（一只游隼（Buteo swainsoni）和一只红尾鹰（Buteo jamaicensis））进行了剖检，并采集组织进行培养。对培养的原体的测序显示，与最近描述的衣原体 buteonis 的平均核苷酸同一性为 99.97%。在加利福尼亚州北部发现了血清阳性猛禽和衣原体 DNA 阳性猛禽的空间聚集。感染在冬季最为流行。此外，虽然不同年龄组的猛禽检测出衣原体 DNA 的比例相似，但血清阳性率在成年猛禽中最高。本研究对衣原体 buteonis 的宿主范围提出了质疑，并强调了进一步研究评估感染猛禽种群的衣原体 spp.多样性和流行病学的重要性。
