State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.
Subei Mongolian Autonomous County Center for Disease Control and Prevention, Jiuquan, China.
BMC Genomics. 2022 Apr 30;23(1):335. doi: 10.1186/s12864-022-08557-x.
Human granulocytic anaplasmosis is a tick-borne zoonotic disease caused by Anaplasma phagocytophilum. Coinfections with A. phagocytophilum and other tick-borne pathogens are reported frequently, whereas the relationship between A. phagocytophilum and flea-borne Yersnia pestis is rarely concerned.
A. phagocytophilum and Yersnia pestis were discovered within a Marmota himalayana found dead in the environment, as determined by 16S ribosomal rRNA sequencing. Comparative genomic analyses of marmot-derived A. phagocytophilum isolate demonstrated its similarities and a geographic isolation from other global strains. The 16S rRNA gene and GroEL amino acid sequence identity rates between marmot-derived A. phagocytophilum (JAHLEX000000000) and reference strain HZ (CP000235.1) are 99.73% (1490/1494) and 99.82% (549/550), respectively. 16S rRNA and groESL gene screenings show that A. phagocytophilum is widely distributed in marmots; the bacterium was more common in marmots found dead (24.59%, 15/61) than in captured marmots (19.21%, 29/151). We found a higher Y. pestis isolation rate in dead marmots harboring A. phagocytophilum than in those without it ( = 4.047, p < 0.05). Marmot-derived A. phagocytophilum was able to live in L929 cells and BALB/c mice but did not propagate well.
In this study, A. phagocytophilum was identified for the first time in Marmota himalayana, a predominant Yersinia pestis host. Our results provide initial evidence for M. himalayana being a reservoir for A. phagocytophilum; moreover, we found with the presence of A. phagocytophilum, marmots may be more vulnerable to plague. Humans are at risk for co-infection with both pathogens by exposure to such marmots.
人类粒细胞无形体病是一种由嗜吞噬细胞无形体引起的蜱传性人畜共患病。常报告有嗜吞噬细胞无形体与其他蜱传病原体的合并感染，而无形体与跳蚤传播的鼠疫耶尔森菌之间的关系则很少受到关注。
通过 16S 核糖体 rRNA 测序发现，在一只死亡的喜马拉雅旱獭体内发现了嗜吞噬细胞无形体和鼠疫耶尔森菌。对旱獭来源的嗜吞噬细胞无形体分离株的比较基因组分析表明，它与其他全球菌株具有相似性和地理隔离性。旱獭来源的嗜吞噬细胞无形体（JAHLEX000000000）与参考株 HZ（CP000235.1）的 16S rRNA 基因和 GroEL 氨基酸序列同一性率分别为 99.73%（1490/1494）和 99.82%（549/550）。16S rRNA 和 groESL 基因筛查表明，嗜吞噬细胞无形体广泛分布于旱獭中；在死亡旱獭（24.59%，15/61）中比在被捕旱獭（19.21%，29/151）中更为常见。我们发现，携带嗜吞噬细胞无形体的死亡旱獭中鼠疫耶尔森菌的分离率高于不携带的旱獭（=4.047，p<0.05）。旱獭来源的嗜吞噬细胞无形体能够在 L929 细胞和 BALB/c 小鼠中存活，但繁殖情况不佳。
在这项研究中，首次在喜马拉雅旱獭中发现了嗜吞噬细胞无形体，这是鼠疫耶尔森菌的主要宿主。我们的结果初步表明喜马拉雅旱獭可能是嗜吞噬细胞无形体的储存宿主；此外，我们发现，携带嗜吞噬细胞无形体的旱獭可能更容易感染鼠疫。人类因接触这种旱獭而有同时感染这两种病原体的风险。
