Anaplasma phagocytophilum in white-tailed deer

We examined the reservoir potential of white-tailed deer for Anaplasma phagocytophilum. Results suggest that white-tailed deer harbor a variant strain not associated with human infection, but contrary to published reports, white-tailed deer are not a reservoir for strains that cause human disease. These results will affect surveillance studies of vector and reservoir populations.     

Human Granulocytic Anaplasmosis,Japan

We retrospectively confirmed 2 cases of human Anaplasma phagocytophilum infection. Patient blood samples contained unique p44/msp2 for the pathogen, and antibodies bound to A. phagocytophilum antigens propagated in THP-1 rather than HL60 cells. Unless both cell lines are used for serodiagnosis of rickettsiosis-like infections, cases of human granulocytic anaplasmosis could go undetected.     

2010-2011无年形我体国的东感北染林情区况蜱调中查嗜吞噬细胞

目的调查我国东北林区蜱标本中嗜吞噬细胞无形体的感染情况。方法2010-2011年在东北林区采集蜱标本,用聚合酶链反应方法扩增gltA基因片段,分析东北林区蜱中无形体的感染情况,代表阳性片段联用长片段16S rRNA进行扩增测序确认;并将所得序列与GenBank中已注册的序列进行比对分析。结果共检测蜱2293只,其中2010年1161只,阳性率4.91%,2011年1132只,阳性率4.24%,2年的感染率差异无统计学意义(χ2=0.373,P=0.830;χ2=1.789,P=0.409)。全沟硬蜱阳性率4.86%(91/1872),长角血蜱为3.41%(14/411),森林革蜱为0(0/10),3个蜱种的感染率差异无统计学意义(P>0.05)。测得的gltA序列中,NE-gltA-1与Hc346株(GenBank:GU935788)最相似,仅差2 bp,相似性99%;NE-gltA-2与MDJ-Ip92株(HQ396224)序列一致,相似性100%。与2个序列相似性最远的是ZJ-HGA-72株(DQ458811),相差53 bp,相似性84%。测得的16S rRNA序列与我国从东北鼠源分离株China-C-T(tGQ412339)最接近,相似性为99%,与Florida株(AF309867)相似性最远,相似性97%。结论我国东北林区蜱中普遍存在嗜吞噬细胞无形体的感染,全沟硬蜱和长角血蜱可能为无形体的媒介宿主。     

Anaplasma phagocytophilum infection in Ixodes ricinus, Bavaria, Germany

Anaplasma phagocytophilum DNA was detected by real-time PCR, which targeted the msp2 gene, in 2.9% of questing Ixodes ricinus ticks (adults and nymphs; n = 2,862), collected systematically from selected locations in Bavaria, Germany, in 2006. Prevalence was significantly higher in urban public parks in Munich than in natural forests.     

安徽地区家畜嗜吞噬细胞无形体16S rRNA基因检测和序列分析

目的了解安徽农村地区散养家畜自然感染嗜吞噬细胞无形体状况和基因特征。方法应用巢式PCR对怀远、明光和广德县采集的148份家畜全血样本进行嗜吞噬无形体16S rRNA基因检测,并对扩增产物测序,应用生物软件MEGA4.0进行序列分析。结果 148份家畜全血样本中检测出山羊、牛和犬嗜吞噬细胞无形体16S rRNA基因阳性率分别22.1%、25.0%和40.0%。26份PCR阳性扩增产物测序成功,序列分析结果表明：检出序列可归为4群,I群优势株占分析序列的66.7%,与北京、浙江和湖北等地检测序列同属一个分支。目的基因测定序列与参考序列同源性达97.0~99.0%。结论安徽调查地区农村家畜动物存在嗜吞噬细胞无形体感染,山羊是该地区嗜吞噬细胞无形体的重要宿主动物之一。     

东北林区鼠类粒细胞埃立克体感染的调查

目的了解东北林区啮齿动物感染粒细胞埃立克体病原体的情况。方法运用聚合酶链反应方法对吉林、黑龙江、内蒙古林区采集的啮齿动物标本粒细胞埃立克体的16S rRNA和gltA基因片段进行检测并测序,将所测序列与GenBank中注册的基因序列进行比较分析。结果共检测鼠标本276份,其中吉林长白山林区102份,黑龙江小兴安岭林区61份,内蒙古大兴安岭林区113份,阳性率分别为8.82%、1.64%及0.00%。体表有寄生蜱的鼠感染危险性是体表无寄生蜱鼠的11.30倍(P=0.002)。吉林、黑龙江林区鼠标本及其寄生蜱标本16S rRNA基因序列完全相同,与美国、瑞典、日本等国家检出的粒细胞埃立克体对应序列的同源性为97%-99%。gltA基因核苷酸序列与GenBank注册的相应片段比较相似性为87%-97%,推导的氨基酸序列相似性为84%-99%。结论吉林及黑龙江林区存在粒细胞埃立克体宿主动物感染。     

Anaplasma phagocytophilum, Babesia microti, and Borrelia burgdorferi in Ixodes scapularis, southern coastal Maine

Ixodes scapularis (deer ticks) from Maine were tested for multiple infections by polymerase chain reaction and immunofluorescence. In 1995, 29.5%, 9.5%, and 1.9% of deer ticks were infected with Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti, respectively. In 1996 and 1997, the number of A. phagocytophilum-infected ticks markedly declined. In 1995 through 1996, 4 (1.3%) of 301 were co-infected.     

Anaplasma phagocytophilum infection in small mammal hosts of Ixodes ticks, western United States

A total of 2,121 small mammals in California were assessed for Anaplasma phagocytophilum from 2006 through 2008. Odds ratios were >1 for 4 sciurids species and dusky-footed woodrats. High seroprevalence was observed in northern sites. Ten tick species were identified. Heavily infested rodent species included meadow voles, woodrats, deer mice, and redwood chipmunks.     

中国西南横断山区小型兽类嗜吞噬细胞无形体基因的检测及序列测定

目的 了解中国西南横断山区小型兽类自然感染嗜吞噬细胞无形体的情况.方法 采集位于滇西北横断山区的高黎贡山山脉、香格里拉雪山等山地(海拔1000～4500m)林区的小型兽类脏器标本以低温保存和运输,所获标本在实验室应用聚合酶链反应(PCR)方法对嗜吞噬细胞无形体16S rRNA基因和Msp4基因片段进行扩增测序,并将所测序列与GenBank中注册的基因序列进行相似性比较.结果 共检测小型兽类5目18属35种共436只,从6属11种小型兽类中发现阳性标本32份,总阳性率为7.34%.其中,高黎贡山林区检测小型兽类标本25种301只,阳性26份,阳性率为8.64%(26/301);香格里拉雪山等林区检测小型兽类标本19种135只,阳性6份,阳性率为4.44%(6/135);阳性标本绝大部分发现于小型兽类中的啮齿类动物.序列比较分析表明:不同小型兽类间的16S rRNA基因序列相似性为99%～100%,且与吉林野鼠中检测的无形体相对应片段(GenBank:DQ449948)最相近,相似性达99%～100%.对其Msp4基因核苷酸序列进一步分析发现与GenBank中相应片段相似性为95%～97%,提示中国西南横断山区小型兽类所感染无形体株变异较大.结论 首次证实和发现中国西南横断山区6属11种小型兽类自然感染嗜吞噬细胞无形体,其中啮齿类动物可能是这一地区嗜吞噬细胞无形体的主要宿主.     

蜱类携带粒细胞无形体的核酸检测及核酸序列分析

目的了解蜱类自然感染粒细胞无形体(anaplasma phagocytophilum)的状况,为人粒细胞无形体病的预防、控制提供技术支持。方法利用分子生物学技术,通过对野外采集的蜱类样品的核酸(DNA)提取、聚合酶链反应(套式PCR)、凝胶电泳分析以及核酸序列分析等,对蜱类携带的粒细胞无形体进行确认。结果在大连地区采集的长角血蜱(Haemaphysalis longicornis)中检测到粒细胞无形体。序列分析结果表明,与GenBank数据库中已注册的粒细胞无形体核酸序列有高度的相似性(97%～99%)。结论我国大连地区存在蜱粒细胞无形体感染。应加强对该地区蜱类的监测和控制,防止因蜱类叮咬导致人粒细胞无形体病的暴发流行。     

Diversity of Anaplasma phagocytophilum Strains, USA

We analyzed the structure of the expression site encoding the immunoprotective protein MSP2/P44 from multiple Anaplasma phagocytophilum strains in the United States. The sequence of p44ESup1 had diverged in Ap-variant 1 strains infecting ruminants. In contrast, no differences were detected between A. phagocytophilum strains infecting humans and domestic dogs.     

Wild boars as hosts of human-pathogenic Anaplasma phagocytophilum variants

To investigate the potential of wild boars to host Anaplasma phagocytophilum, we analyzed bacterial 16S rRNA and ank genes. DNA sequencing identified several A. phagocytophilum variants, including a predominance of strains known to cause human disease. Boars are thus hosts for A. phagocytophilum, notably, strains associated with human granulocytic anaplasmosis.     

山西省宁武县森林革蜱无形体分子流行病学调查

人粒细胞无形体病是由嗜吞噬无形体引起的新发蜱传人兽共患病,在我国一些地区广泛存在[1,2].该病传播媒介主要为硬蜱.宁武县是山西省重点林业县,生态环境适宜蜱的生长和繁殖,农林作业及家畜养殖人员多数有蜱暴露史或叮咬史.为此,山西省疾病预防控制中心与中国疾病预防控制中心无形体研究室合作对该地区进行无形体病原体分子流行病学调查.     

Associations of Anaplasma phagocytophilum Bacteria Variants in Ixodes scapularis Ticks and Humans,New York,USA

Anaplasmosis, caused by the tickborne bacterium Anaplasma phagocytophilum, is an emerging public health threat in the United States. In the northeastern United States, the blacklegged tick (Ixodes scapularis) transmits the human pathogenic genetic variant of A. phagocytophilum (Ap-ha) and a nonpathogenic variant (Ap-V1). New York has recently experienced a rapid and geographically focused increase in cases of anaplasmosis. We analyzed A. phagocytophilum–infected I. scapularis ticks collected across New York during 2008–2020 to differentiate between variants and calculate an entomological risk index (ERI) for each. Ap-ha ERI varied between regions and increased in all regions during the final years of the study. Space-time scan analyses detected expanding clusters of Ap-ha located within documented anaplasmosis hotspots. Ap-ha ERI was more positively correlated with anaplasmosis incidence than non-genotyped A. phagocytophilum ERI. Our findings help elucidate the relationship between the spatial ecology of A. phagocytophilum variants and anaplasmosis.     

Two Anaplasma phagocytophilum Strains in Ixodes scapularis Ticks,Canada

We developed PCR-based assays to distinguish a human pathogenic strain of Anaplasma phagocytophilum, Ap-ha, from Ap-variant 1, a strain not associated with human infection. The assays were validated on A. phagocytophilum-infected blacklegged ticks (Ixodes scapularis) collected in Canada. The relative prevalence of these 2 strains in I. scapularis ticks differed among geographic regions.