State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China.
Mudanjiang Forestry Central Hospital, Mudanjiang, Heilongjiang Province, China.
Lancet Infect Dis. 2015 Jun;15(6):663-70. doi: 10.1016/S1473-3099(15)70051-4. Epub 2015 Mar 29.
Anaplasma phagocytophilum and Anaplasma ovis cause human infections. We investigated the potential for human pathogenicity of a newly discovered Anaplasma species infecting goats in China.
We collected blood samples from patients with a history of tick bite in the preceding 2 months at Mudanjiang Forestry Central Hospital of Heilongjiang Province from May 1, to June 10, 2014, to detect the novel Anaplasma species by PCR. We inoculated positive samples into cell cultures. We characterised the isolated pathogen by morphological and phylogenetic analyses. We tested serum antibodies by indirect immunofluorescence assay.
28 (6%) of 477 patients assessed were infected with the novel Anaplasma species according to PCR and sequencing. We isolated the pathogen in vitro from three patients. Phylogenetic analyses of rrs, gltA, groEL, msp2, and msp4 showed that the pathogen was distinct from all known Anaplasma species. We provisionally nominate it "Anaplasma capra". 22 (92%) of 24 patients with data available had seroconversion or a four-fold increase in antibody titres. All 28 patients developed non-specific febrile manifestations, including fever in 23 (82%), headache in 14 (50%), malaise in 13 (46%), dizziness in nine (32%), myalgia in four (14%), and chills in four (14%). Additionally, ten (36%) of 28 patients had rash or eschar, eight (29%) had lymphadenopathy, eight (29%) had gastrointestinal symptoms, and three (11%) had stiff neck. Five patients were admitted to hospital because of severe disease. Six (35%) of 17 patients with data available had high hepatic aminotransferase concentrations.
The emergence of "A capra" as a cause of human disease suggests that individuals living in or travelling to endemic regions in northern China should take precautions to reduce their risk of exposure to this novel tick-borne pathogen.
Natural Science Foundation of China and the US National Institutes of Health.
嗜吞噬细胞无形体和绵羊无浆体可引起人类感染。我们研究了在中国感染山羊的一种新发现的无形体物种的潜在人类致病性。
我们于 2014 年 5 月 1 日至 6 月 10 日期间，从黑龙江省牡丹江市林业中心医院收集有蜱叮咬史的患者的血液样本，通过 PCR 检测新型无形体物种。我们将阳性样本接种到细胞培养物中。通过形态学和系统发育分析来描述分离出的病原体。我们通过间接免疫荧光测定法检测血清抗体。
根据 PCR 和测序结果，477 名评估患者中 28 名（6%）感染了新型无形体物种。我们从 3 名患者中体外分离出病原体。rrs、gltA、groEL、msp2 和 msp4 的系统发育分析表明，该病原体与所有已知的无形体物种都不同。我们暂时将其命名为“山羊无形体”。24 名有数据的患者中，22 名（92%）发生血清转换或抗体滴度增加四倍。28 名患者均出现非特异性发热表现，包括发热 23 例（82%）、头痛 14 例（50%）、不适 13 例（46%）、头晕 9 例（32%）、肌痛 4 例（14%）和寒战 4 例（14%）。此外，28 名患者中有 10 名（36%）出现皮疹或焦痂、8 名（29%）出现淋巴结病、8 名（29%）出现胃肠道症状、3 名（11%）出现颈项强直。5 名患者因病情严重住院。17 名有数据的患者中有 6 名（35%）出现高肝转氨酶浓度。
“山羊无形体”作为人类疾病的病因出现表明，生活在中国北方流行地区或前往该地区的个体应采取预防措施，降低感染这种新型蜱传病原体的风险。
中国自然科学基金和美国国立卫生研究院。
