Anaplasma phagocytophilum transmitted through blood transfusion--Minnesota, 2007

Anaplasma phagocytophilum, a gram-negative, obligate intracellular bacterium of neutrophils, causes human anaplasmosis, a tickborne rickettsial disease formerly known as human granulocytic ehrlichiosis. In November 2007, the Minnesota Department of Health was contacted about A. phagocytophilum infection in a hospitalized Minnesota resident who had recently undergone multiple blood transfusions. Subsequent investigation indicated the infection likely was acquired through a transfusion of red blood cells. This report describes the patient's clinical history and the epidemiologic and laboratory investigations. Although a previous case of transfusion-transmitted anaplasmosis was reported, this is the first published report in which transfusion transmission of A. phagocytophilum was confirmed by testing of the recipient and a donor. Although polymerase chain reaction (PCR) assays provided reliable evidence of transmission in this case, no cost-effective method for screening blood donors for A. phagocytophilum exists. Screening donors for a recent history of tick bite is not likely to be sensitive or specific because such exposures are common and often not recalled by persons with anaplasmosis. Physicians should consider the possibility of anaplasmosis in patients who develop posttransfusion acute thrombocytopenia, especially if accompanied by fever, and should report suspected transfusion-associated cases to health authorities.     

Babesia microti and Anaplasma phagocytophilum: two emerging zoonotic pathogens in Europe and Hungary

Babesia microti and Anaplasma phagocytophilum was recently reported with a minimum prevalence of 0.9 and 1.3% in Hungary based on the PCR-sequencing analysis of 452 European sheep ticks (Ixodes ricinus). These results and the epidemiological data of the neighbouring countries indicate that human cases caused by these pathogens may occur in the country. The aim of the present paper is to summarise the current knowledge on the morphology, life cycle and distribution of B. microti and A. phagocytophilum, and the epidemiology, clinical features, diagnosis, treatment and control of babesiosis and granulocytic anaplasmosis.     

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.     

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。     

Genetic diversity of Anaplasma bacteria: Twenty years later

The genus Anaplasma (family Anaplasmataceae, order Rickettsiales) includes obligate intracellular alphaproteobacteria that multiply within membrane-bound vacuoles and are transmitted by Ixodidae ticks to vertebrate hosts. Since the last reclassification of Anaplasmataceae twenty years ago, two new Anaplasma species have been identified. To date, the genus includes eight Anaplasma species (A. phagocytophilum, A. marginale, A. centrale, A. ovis, A. bovis, A. platys, A. odocoilei, and A. capra) and a large number of unclassified genovariants that cannot be assigned to known species. Members of the genus can cause infection in humans and a wide range of domestic animals with different degrees of severity. Long-term persistence which, in some cases, is manifested as cyclic bacteremia has been demonstrated for several Anaplasma species. Zoonotic potential has been shown for A. phagocytophilum, the agent of human granulocytic anaplasmosis, and for some other Anaplasma spp. that suggests a broader medical relevance of this genus. Genetic diversity of Anaplasma spp. has been intensively studied in recent years, and it has been shown that some Anaplasma spp. can be considered as a complex of genetically distinct lineages differing by geography, vectors, and host tropism. The aim of this review was to summarize the current knowledge concerning the natural history, pathogenic properties, and genetic diversity of Anaplasma spp. and some unclassified genovariants with particular attention to their genetic characteristics. The high genetic variability of Anaplasma spp. prompted us to conduct a detailed phylogenetic analysis for different Anaplasma species and unclassified genovariants, which were included in this review. The genotyping of unclassified genovariants has led to the identification of at least four distinct clades that might be considered in future as new candidate species.     

黑龙江林区出入境人员嗜吞噬细胞无形体血清抗体检测

〔目的〕了解东北林区出入境人员嗜吞噬细胞无形体抗体水平。评估我国东北林区出入境人员嗜吞噬细胞无形体感染的潜在公共卫生危害,为人粒细胞无形体病的防控提供流行病学资料。〔方法〕采用间接免疫荧光检测方法对东北林区出入境体检人群血清嗜吞噬细胞无形体抗体进行检测,并对检测结果进行统计分析。〔结果〕共检测243份血清,其中阳性8份,阳性率为3.29%,1份抗体滴度达到1:320。〔结论〕我国东北林区人群中可能存在嗜吞噬细胞无形体既往感染。     

Rickettsia sp. and Anaplasma spp. in Haemaphysalis longicornis from Shandong province of China,with evidence of a novel species “Candidatus Anaplasma Shandongensis”

Haemaphysalis longicornis is one of the most dominant and widespread tick species in China. This species mainly infests wild animals and occasionally attacks humans, and has been associated with the transmission of a variety of zoonotic pathogens including spotted fever group Rickettsia (SFGR), severe fever with thrombocytopenia syndrome virus (SFTSV), Anaplasma phagocytophilum, Babesia spp. and Theileria spp.. Although there are increasing reports of various pathogens associated with H. longicornis, some neglected pathogens in certain areas still need to be studied. In this study, a total of 171 H. longicornis ticks were collected from goats in three locations of Shandong Province, Eastern China (Zibo, Linyi, and Qingdao cities), and subsequently screened for the presence of Rickettsia, Anaplasma, and Ehrlichia bacteria. A total of four bacterial species were identified and characterized. “Candidatus Rickettsia jingxinensis” was detected in one tick specimen from Zibo city. Of 98 ticks from Linyi city, 63.27% (62/98) were tested positive for Anaplasma capra and 5.10% (5/98) were positive for Anaplasma bovis. Interestingly, a novel Anaplasma species was detected and characterized in one tick specimen from Zibo and one other from Linyi, respectively. Genetic and phylogenetic analysis based on the 16S, gltA, groEL, and msp4 genes indicated that it was divergent from all known Anaplasma species but mostly related to A. phagocytophilum and “Cadidatus Anaplasma boleense”. Based on where it was first detected, we named it “Candidatus Anaplasma shandongensis”.     

浙江首例人粒细胞无形体病患者病原学分析

目的 对浙江首例疑似人粒细胞无形体病(HGA)患者进行病原学诊断与分子生物学分析.方法 运用分子生物学方法检测吞噬细胞无形体16S rRNA,间接免疫荧光法(IFA)检测患者临床症状期和恢复健康3个月后血清吞噬细胞无形体IgG抗体.结果 患者发热期血液PCR获得的16S rRNA基因片段:282 bp和389 bp,符...     

First molecular detection and genetic analysis of Anaplasma phagocytophilum in shelter cats in Seoul,Korea

Here, we report the molecular detection of Anaplasma phagocytophilum in shelter cats in Korea and the relationships between A. phagocytophilum gene sequences and the pathogenicity, region, and host specificity of this bacterium. Two (0.9%) out of 222 shelter cats from Seoul, Korea, yielded positive results for the A. phagocytophilum 16S rRNA, groEL, and msp2 genes. Phylogenetic analysis divided groEL gene sequences into two groups (alanine and serine), based on their nucleotide and amino acid sequences. A. phagocytophilum msp2 gene sequences were grouped per the region of isolation (Europe vs. USA, including Korea). Some nucleotide and amino acid sequences of groEL and msp2 showed distinctive patterns according to the region of isolation, which helped in distinguishing A. phagocytophilum gene sequences detected in Korea from those detected in the USA and Europe. Although the limited number of clinical anaplasmosis cases caused by A. phagocytophilum belonging to the alanine group prevents any firm conclusions, the results of the present study tend to refute the previous view that the pathogenicity of A. phagocytophilum is associated with the serine group. Moreover, our results suggest that genetic analyses of groEL and msp2 can be used to obtain a regional fingerprint of A. phagocytophilum.     

Prevalence and molecular characterization of Anaplasma phagocytophilum in roe deer (Capreolus capreolus) from Spain

Anaplasma phagocytophilum can infect a wide range of vertebrates; nevertheless, some genetic variants are associated with particular species of tick vectors and animal hosts. It has been suggested that roe deer (Capreolus capreolus) mainly acts as a reservoir of several A. phagocytophilum non-pathogenic variants for other animal species. The aim of this study was to determine the prevalence and identify the genetic variants of A. phagocytophilum in roe deer from Spain in order to assess host-pathogen associations and their pathogenic potential.The spleens of 212 roe deer hunted in Spain were individually collected and analysed by a commercial qPCR kit in order to detect the presence of A. phagocytophilum DNA. Positive samples were further characterized at groESL, 16S rRNA and msp2 partial genes. The possible influence of several intrinsic (age and sex) and extrinsic factors (ecological area) on A. phagocytophilum prevalence was analysed using a logistic regression.Overall, 41.5 % of the samples resulted positive to A. phagocytophilum. The percentage of infected roe deer was significantly higher in the Mediterranean and Oceanic areas than in the Continental and Mountain regions; nevertheless, prevalence was not related to age or sex. Sequence analysis at groESL and 16S rRNA genes allowed the identification of three ecotypes (I to III) and four variants (“Y”, “X”, “W”, “I”), respectively. A high percentage of roe deer from Spain is infected with different variants of A. phagocytophilum; these results have implications for public and animal health since some of these ecotypes and variants have been previously identified in both human and animal clinical cases.     

Anaplasma phagocytophilum-infected ticks, Japan

We report Anaplasma phagocytophilum infection of Ixodes persulcatus and I. ovatus ticks in Japan. Unique p44/msp2 paralogs (and/or 16S rRNA genes) were detected in tick tissues, salivary glands, and spleens of experimentally infected mice. These findings indicate the public health threat of anaplasmosis in Japan.     

Serological and molecular detection of Anaplasma phagocytophilum in Thoroughbred horses from Chilean racecourses

Anaplasma phagocytophilum is the causative agent of equine granulocytic anaplasmosis (EGA). This study aimed to perform serological and molecular surveys of A. phagocytophilum in thoroughbred horses from racecourses in Chile. Additionally, hematological findings related to A. phagocytophilum molecular positivity were addressed, and phylogenetic analysis of selected positive samples was performed. Complete blood count and msp2 gene real-time PCR were performed in 457 thoroughbred horses from three racecourses located in three different cities of Chile (Santiago, Viña del Mar and Concepción). Sera from horses in two racecourses (Santiago and Vina del Mar) were tested by Indirect fluorescent antibody test (IFAT) to detect IgG antibodies against A. phagocytophilum. The occurrence of A. phagocytophilum by real-time PCR was 13.6 % (62/457, 95 % CI: 10.8–16.3 %), with the highest occurrence observed in Santiago (26.5 %), followed by Concepción (9%), and the lowest in Viña del Mar (5%). The overall frequency of IgG antibodies to A. phagocytophilum was 7.9 % (23/290, 95 % CI: 4.8–12.7 %), with 9.9 % in Santiago and 6.5 % in Viña del Mar. Only three animals from Santiago Racecourse were positive in both real-time PCR and serology. PCR-positive horses from Santiago racecourse presented significantly lower hemoglobin, mean corpuscular value (MCV), and mean corpuscular hemoglobin concentration (CHCM), and higher eosinophil counts. Phylogenetic analysis based on the msp2 gene showed that A. phagocytophilum sequences found in the present study were closely related with A. phagocytophilum sequences from the USA and Europe. Anaplasma phagocytophilum DNA is detected for the first time in Chile.     

Epidemiology and genetic diversity of Anaplasma marginale in Zamora-Chinchipe,Ecuador

Bovine anaplasmosis, caused by the tick-borne pathogen Anaplasma marginale, is a hemolytic disease that constitutes a major constraint to cattle production in tropical and subtropical regions including Ecuador. However, the epidemiological situation of this hemoparasitosis in Ecuador is poorly characterized. The present study was aimed to determine the prevalence and genetic diversity of A. marginale in cattle of Ecuador. A cross-sectional study was carried out covering several farms from six out nine cantons of the Zamora-Chinchipe province. A total of 185 cattle were randomly selected and blood samples were collected from the animals. The studied group of animals included six breeds, three age groups, and both sexes. The molecular diagnostic was performed based on a nPCR assay targeting the A. marginale msp5 gene. Anaplasma marginale prevalence was 63.8 % and the bacteria were detected in all the cantons studied. Thirteen representative strains were selected and genetically characterized based on the msp1α gene. Genetic diversity analysis revealed that different strains circulate in the bovine herds studied. The results suggest that cattle movement may contribute to the circulation of common strains in the area. The results demonstrate a high prevalence of A. marginale in the region which should be considered by the sanitary authorities. The epidemiological surveillance for this disease should increase to anticipate acute disease outbreaks with high mortality. Bovine anaplasmosis outbreaks can cause economic losses and the death of several animals; therefore, measures for the prevention and control of this disease are required.     

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.     

Real-time PCR assay with an endogenous internal amplification control for detection and quantification of Anaplasma marginale in bovine blood

Bovine anaplasmosis is a tick-borne rickettsial disease, causing significant economic losses in many countries. The main causative agent of bovine anaplasmosis is Anaplasma marginale (Rickettsiales, Anaplasmataceae). To date, several PCR assays for A. marginale DNA detection were proposed, but most of them do not provide an internal amplification control, which allows to prevent false-negative results and is required for reliability of the results of pathogen DNA detection by PCR assay. In the present study, a real-time PCR assay based on the species-specific and highly conserved fragment of msp1α gene was developed for detection and quantification of A. marginale in bovine blood. The real-time PCR assay is able to detect as few as one copу of msp1α gene per reaction. To prevent false-negative results, simultaneous amplification and detection of the bovine genomic DNA fragment as an endogenous internal amplification control (IAC) was provided. The assay can be used as a highly specific and sensitive method for detection and quantification of A. marginale in infected cattle, and for the evaluation of the efficacy of anti-rickettsial drugs and anaplasmosis vaccines.     

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。     

An epidemiological survey of equine anaplasmosis (Anaplasma phagocytophilum) in southern France

Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum and transmitted by Ixodes spp. ticks. According to some reports the disease can be introduced into disease-free zones by migrating birds. The purpose of this study was to evaluate the seroprevalence of A. phagocytophilum in horses in the Camargue. Data concerning 424 horses were gathered and the sera were tested for A. phagocytophilum and for piroplasmoses using an enzyme-linked immunosorbent assay and a complement fixation test, respectively. The seroprevalence rates were 11.3 % for A. phagocytophilum, 64.4 % for Theileria equi and 19.7% for Babesia caballi. Stallions were less likely to produce antibodies against A. phagocytophilumthan were females or geldings (odds ratio [OR] = 0.3; p = 0.021). The presence of swallows increased the risk of infections in stables (OR = 5.18; p = 0.011). Spatial analysis showed the existence of groups of infected stables along canals and rivers (p = 0.008). These results suggest an emergence of A. phagocytophilum in the Camargue.     

Seroprevalence of Anaplasma spp. and Ehrlichia spp. and molecular detection of Anaplasma phagocytophilum and Anaplasma platys in stray dogs in Bosnia and Herzegovina

Stray dogs may be highly exposed to vector-borne pathogens (VBPs), including zoonotic agents, and therefore may pose a high risk of spreading infections to other animals and humans. Among the Anaplasmataceae, Anaplasma phagocytophilum, A. platys and Ehrlichia canis are commonly identified species in dogs in Europe; however, information on the occurrence of these pathogens in canine populations from Bosnia and Herzegovina (B&H) is still lacking. Thus, the aim of this study was to determine the seroprevalence of Anaplasma spp. and Ehrlichia spp. in stray dogs in the Sarajevo region of B&H and to identify A. phagocytophilum, A. platys, E. canis and E. ewingii by molecular techniques. A total of 903 blood samples of stray dogs were screened by SNAP 4Dx Plus Test for the presence of antibodies against A. phagocytophilum/A. platys and E. canis/E. ewingii. Real-time PCR assays were performed for the detection of Anaplasmataceae, A. phagocytophilum, A. platys, E. canis and E. ewingii in seropositive dogs. Antibodies to A. phagocytophilum/A. platys and/or E. canis/E. ewingii were detected in 187 (20.7%) samples. Seroprevalence was highest for A. phagocytophilum/A. platys (184/903, 20.4%). Two dogs had antibodies to E. canis/E. ewingii, while one dog was found to have antibodies to A. phagocytophilum/A. platys and to E. canis/E. ewingii. Forty-eight (25.7%) of the 187 seropositive dogs examined by Real-time PCR were positive for Anaplasmataceae. A. phagocytophilum was detected in 45 (24%) samples, while one sample was positive for A. phagocytophilum and A. platys. Two samples positive for Anaplasmataceae tested negative in the species-specific PCRs. E. canis or E. ewingii could not be detected in any of the Ehrlichia-seropositive dogs. These findings highlight the need for dog health monitoring, improving the health and welfare of stray dog population, and establishment of effective surveillance systems to combat VBDs.     

Seroepidemiology of Borrelia burgdorferi sensu lato and Anaplasma phagocytophilum in wild mice captured in northern Turkey

An expedition across the Asian part of the Black Sea coast and national parks of Northern Turkey was organized in the summer of 2001 to investigate the presence of Borrelia burgdorferi sensu lato (s.l.), Lyme borreliosis agent, and Anaplasma phagocytophilum, human granulocytic ehrlichiosis, agent, in wild mice. A total of 65 Apodemus flavicollis, Apodemus sylvaticus, Microtus epiroticus, Crocidura suaveolens and Mus macedonicus, were captured. Two out of 22 Apodemus sylvaticus specimens were seropositive for B. afzelii by enzyme-linked immunosorbent assay as confirmed by Western blotting, however cultures of skin and bladder samples from all small mammals in Barbour-Stoenner-Kelly's medium-II remained negative for B. burgdorferi s.l. All sera tested were negative for Anaplasma phagocytophilum by indirect immunofluorescent assay. The prevalence of B. burgdorferi s.l. and Anaplasma phagocytophilum is low in wild mice of the Asian part of Northern Turkey.