Lyme Neuroborreliosis in Children: Etiology and Comparison of Clinical Findings of Lyme Neuroborreliosis Caused by Borrelia garinii and Borrelia afzelii.

BACKGROUND: Information on the etiology of Lyme neuroborreliosis (LNB) in children in Europe and the influence of Borrelia burgdorferi sensu lato species isolated from cerebrospinal fluid (CSF) on clinical presentation of LNB in children are limited. METHODS: The study was monocentric. During its 17-year period, children younger than 15 years with presentation suggestive of LNB or confirmed Lyme borreliosis that had B. burgdorferi sensu lato isolated from CSF and had species of B. burgdorferi sensu lato identified by pulsed-field gel electrophoresis were included. Demographic and medical data were compared for children infected with Borrelia garinii to those infected with Borrelia afzelii. RESULTS: One hundred and fifty-three children had B. burgdorferi sensu lato isolated from CSF. In 71/113 (62.8%) and 42/113 (37.2%) patients, B. garinii and B. afzelii, respectively, were identified. Patients infected with B. garinii did not report symptoms suggestive of central nervous system (CNS) involvement or any other symptoms more often than patients infected with B. afzelii. Compared with children infected with B. afzelii, children infected with B. garinii had erythema migrans less often (18.3% vs. 45.2%) but had positive meningeal signs (69.0% vs. 38.1%), CSF lymphocytic predominance (97.1% vs. 75.0%), and elevated albumin CSF/serum quotient (80.6% vs. 50.0%) more often. CONCLUSIONS: In Slovenia, LNB in children is more often caused by B. garinii, followed by B. afzelii. The clinical picture of LNB in children caused by B. garinii is not more often suggestive of CNS involvement, but CNS inflammation is more pronounced in children infected with B. garinii, compared with children infected with B. afzelii.

Susceptibility to infection with Borrelia afzelii and TLR2 polymorphism in a wild reservoir host.

The study of polymorphic immune genes in host populations is critical for understanding genetic variation in susceptibility to pathogens. Controlled infection experiments are necessary to separate variation in the probability of exposure from genetic variation in susceptibility to infection, but such experiments are rare for wild vertebrate reservoir hosts and their zoonotic pathogens. The bank vole (Myodes glareolus) is an important reservoir host of Borrelia afzelii, a tick-borne spirochete that causes Lyme disease. Bank vole populations are polymorphic for Toll-like receptor 2 (TLR2), an innate immune receptor that recognizes bacterial lipoproteins. To test whether the TLR2 polymorphism influences variation in the susceptibility to infection with B. afzelii, we challenged pathogen-free, lab-born individuals of known TLR2 genotype with B. afzelii-infected ticks. We measured the spirochete load in tissues of the bank voles. The susceptibility to infection with B. afzelii following an infected tick bite was very high (95%) and did not differ between TLR2 genotypes. The TLR2 polymorphism also had no effect on the spirochete abundance in the tissues of the bank voles. Under the laboratory conditions of our study, we did not find that the TLR2 polymorphism in bank voles influenced variation in the susceptibility to B. afzelii infection.

Colonization and pathology of Borrelia afzelii in its natural hosts.

Studies of Borrelia burgdorferi sensu lato in laboratory mice and humans have shown that spirochaetes disseminate from the site of infection (skin) to internal tissues, and cause various pathological effects. However, less is known about colonization and pathology of Lyme borreliosis spirochaetes in their natural hosts. In the present study, we assessed the colonization and manifestations during B. afzelii infection in reservoir hosts (yellow-necked mouse, Apodemus flavicollis; bank vole, Myodes glareolus; common shrew, Sorex araneus) infected in the wild. The infection prevalence and bacterial load was measured in skin (ear), joints and heart by quantitative PCR, and pathology in infected joints was evaluated by histology. The prevalence of B. afzelii was higher in skin than in joints and heart, but most animals that were positive in skin were also positive in internal tissues, and there was no difference between species in tissue-specific prevalence. Thus, spirochaetes disseminated from skin to other tissues in a similar way in all species. The bacterial load varied among host species and among different tissues within the same host species. In the case of skin and joints, bank voles and common shrews had higher bacterial loads than yellow-necked mice. In hearts, voles had higher bacterial loads than shrews and mice. Histological analyses showed no inflammation in joints of infected animals when compared to controls. We conclude that B. afzelii disseminates to internal tissues in natural hosts, but that levels of colonization vary between both species and tissues. There is as yet little evidence for pathological effects in natural hosts.

Borrelia afzelii alters reproductive success in a rodent host.

The impact of a pathogen on the fitness and behaviour of its natural host depends upon the host-parasite relationship in a given set of environmental conditions. Here, we experimentally investigated the effects of Borrelia afzelii, one of the aetiological agents of Lyme disease in humans, on the fitness of its natural rodent host, the bank vole (Myodes glareolus), in semi-natural conditions with two contrasting host population densities. Our results show that B. afzelii can modify the reproductive success and spacing behaviour of its rodent host, whereas host survival was not affected. Infection impaired the breeding probability of large bank voles. Reproduction was hastened in infected females without alteration of the offspring size at birth. At low density, infected males produced fewer offspring, fertilized fewer females and had lower mobility than uninfected individuals. Meanwhile, the infection did not affect the proportion of offspring produced or the proportion of mating partner in female bank voles. Our study is the first to show that B. afzelii infection alters the reproductive success of the natural host. The effects observed could reflect the sickness behaviour due to the infection or they could be a consequence of a manipulation of the host behaviour by the bacteria.

Serología de Borrelia burgdorferi y diagnóstico de la enfermedad de Lyme en el área sanitaria de Santiago de Compostela (Galicia): 2006-2016 / Borrelia burgdorferi serology and diagnosis of Lyme disease in the healthcare area of Santiago de Compostela (Galicia, Spain): 2006-2016

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Golden jackals (Canis aureus) as hosts for ticks and tick-borne pathogens in Serbia.

The golden jackal (Canis aureus) is a medium-sized canid species native to Europe. This species is characterized by rapid large-scale expansion. A similar trend is also observed in Serbia, where the species is now distributed in more than a half of the territory. Although jackals prefer habitats in human-dominated landscapes, these animals have not been studied well enough from an eco-epidemiological point of view, and little is known about their potential for carrying zoonotic pathogens. In a study conducted during a three-year period (01/2010-02/2013), a total of 216 hunted or road-killed golden jackals were collected from 10 localities in Serbia. Ticks, when present, were removed, and after necropsy, spleen samples were collected from each animal. All tick and spleen samples were tested for the DNA of bacterial and protozoan tick-borne pathogens (Borrelia species, Bartonella species, Rickettsia species, Anaplasma species, Coxiella burnetii, Francisella species and Babesia species) by multiplex real-time PCR, conventional PCR and sequencing analyses. The DNA of Babesia canis was detected in nine out of 216 (4.2%) spleen samples, and two samples (0.9%) tested positive for Anaplasma phagocytophilum. In 118 ticks collected from jackals, the DNA of two Babesia species (Ba. canis and Ba. microti), three Borrelia species (Bo. garinii, Bo. valaisiana, and Bo. lusitaniae) and A. marginale was detected. From the aspect of public health surveillance, the potential role of the golden jackal in the maintenance of vector-borne zoonotic pathogens in Serbia must be considered, and further eco-epidemiological studies should be performed to determine the precise role of this animal species in zoonotic disease transmission cycles.

Tick-borne encephalitis virus, Borrelia burgdorferi sensu lato, Borrelia miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis in Ixodes ricinus ticks collected from recreational islands in southern Norway.

The aim of this study was to determine the occurrence of tick-borne pathogens of medical importance in questing ticks collected from five recreationally used islands along the Norwegian coastline. Furthermore, since coinfection may affect the disease severity, this study aimed to determine the extent of coinfection in individual ticks or co-localization of tick-borne pathogens. In all, 4158 questing Ixodes ricinus ticks were analyzed. For detection of tick-borne encephalitis virus (TBEV), nymphs (3690) were analyzed in pools of ten. To detect Borrelia burgdorferi sensu lato, B. miyamotoi, Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis, 468 nymphs were analyzed individually. A total of five nymph pools was infected with TBEV, giving an overall prevalence of 0.14%. In the individually analyzed ticks, B. burgdorferi s. l. (15.6%), Candidatus N. mikurensis (11%), A. phagocytophilum (1.4%) and B. miyamotoi (0.9%) were detected. Coinfection was found in 3.3% of the ticks, and the only dual infection observed was with B. afzelii and Candidatus N. mikurensis. This association was significantly higher than what would occur by random chance.

Borrelia burgdorferi sensu lato prevalence and diversity in ticks and small mammals in a Lyme borreliosis endemic Nature Reserve in North-Western Spain. Incidence in surrounding human populations / Prevalencia y diversidad de Borrelia burgdorferi sensu lato en garrapatas y pequeños mamíferos de una Reserva Natural del noroeste de España donde la borreliosis de Lyme es endémica. Incidencia en las poblaciones humanas circundantes

To determine the prevalence and diversity of Borrelia burgdorferi sensu lato (s.l.) in an endemic Nature Reserve (Sierra del Sueve) in North-Western Spain, and the risk of human exposure to infected ticks in Asturias, 1013 questing ticks and 70 small mammals were collected between 2012 and 2014. A retrospective descriptive analysis was also carried out on human Lyme borreliosis (LB) cases reported to the local hospital (Cabueñes). Samples were screened for B. burgdorferi s.l. presence by a nested PCR assay, and genospecies were confirmed by sequencing. B. burgdorferi s.l. was detected in 1.4% (12/845) of I. ricinus questing nymphs, 9.1% (2/33) of questing adults, and 12.9% (9/70) of small mammals, as well as in the other tick species. PCR positive samples of 17 questing tick and 6 small mammals were sequenced. Four genospecies were identified: B. afzelii, B. garinii, B. lusitaniae, and B. valaisiana. Phylogenetic analyses based on the flaB gene showed the heterogeneity of B. afzelii in this area. The detection of B. burgdorferi s.l. among questing ticks and small mammals in the study area, as well as the abundance of ticks and of large wild and domestic mammals, indicate a high risk of infection by B. burgdorferi s.l. in the area. Reporting of LB cases to the local hospital support this, and shows the need of thorough monitoring of B. burgdorferi infection in ticks and hosts in the area. More investigations are needed to assess the role of different wildlife species and the risk of transmission to humans (AU)

Entre 2012 y 2014 se recogieron 1.013 garrapatas de la vegetación y 70 pequeños mamíferos en la Reserva Natural de la Sierra del Sueve (Asturias) y zonas colindantes, con el fin de determinar la prevalencia de Borrelia burgdorferi sensu lato (s.l.) y el riesgo de exposición humana a garrapatas infectadas en Asturias, área endémica de borreliosis de Lyme. También se incluye un estudio descriptivo y retrospectivo de pacientes diagnosticados de borreliosis en un hospital local (Hospital de Cabueñes, Gijón). B. burgdorferi s.l. se detectó, mediante una PCR anidada, en el 1,4% (12/845) de las ninfas y en el 9,1% (2/33) de los adultos de la garrapata I. ricinus, en porcentajes variables de las restantes especies y en el 12,9% (9/70) de los pequeños mamíferos. Se secuenciaron un total de 17 muestras de garrapatas de la vegetación y 6 de pequeños mamíferos detectándose 4 genoespecies causantes de la borreliosis de Lyme: B. afzelii, B. garinii, B. lusitaniae, y B. valaisiana. Los análisis filogenéticos basados en el gen flaB mostraron la heterogeneidad de B. afzelii en el área de estudio. La detección de B. burgdorferi s.l. en garrapatas de la vegetación y pequeños mamíferos de la zona de estudio, así como la gran abundancia de garrapatas y la presencia de grandes poblaciones de animales silvestres y domésticos, son indicativos de que el riesgo de infección en esta área es relevante. Este hecho está en consonancia con los casos de borreliosis de Lyme descritos en este estudio, mostrando la necesidad de establecer un seguimiento continuado de la enfermedad (AU)

Evolution of antigenic diversity in the tick-transmitted bacterium Borrelia afzelii: a role for host specialization?

Antigenic diversity in pathogenic microbes can be a result of at least three different processes: diversifying selection by acquired immunity, host-pathogen coevolution and/or host specialization. Here, we investigate whether host specialization drives diversity at ospC (which encodes an immunodominant surface protein) in the tick-transmitted bacterium Borrelia afzelii. We determined prevalence and infection intensity of ospC strains in naturally infected wild mammals (rodents and shrews) by 454 amplicon sequencing in combination with qPCR. Neither prevalence nor infection intensity of specific ospC strains varied in a species-specific manner (i.e. there were no significant ospC × host species interactions). Rankings of ospC prevalences were strongly positively correlated across host species. Rankings of ospC infection intensities were correlated more weakly, but only in one case significantly < 1. ospC prevalences in the studied mammals were similar to those in ticks sampled at the study site, indicating that we did not miss any mammal species that are important hosts for specific ospC strains. Based on this, we conclude that there is at best limited host specialization in B. afzelii and that other processes are likely the main drivers of ospC diversity.

Inefficient co-feeding transmission of Borrelia afzelii in two common European songbirds.

The spirochete bacterium Borrelia afzelii is the most common cause of Lyme borreliosis in Europe. This tick-borne pathogen can establish systemic infections in rodents but not in birds. However, several field studies have recovered larval Ixodes ricinus ticks infected with B. afzelii from songbirds suggesting successful transmission of B. afzelii. We reviewed the literature to determine which songbird species were the most frequent carriers of B. afzelii-infected I. ricinus larvae and nymphs. We tested experimentally whether B. afzelii is capable of co-feeding transmission on two common European bird species, the blackbird (Turdus merula) and the great tit (Parus major). For each bird species, four naïve individuals were infested with B. afzelii-infected I. ricinus nymphal ticks and pathogen-free larval ticks. None of the co-feeding larvae tested positive for B. afzelii in blackbirds, but a low percentage of infected larvae (3.33%) was observed in great tits. Transstadial transmission of B. afzelii DNA from the engorged nymphs to the adult ticks was observed in both bird species. However, BSK culture found that these spirochetes were not viable. Our study suggests that co-feeding transmission of B. afzelii is not efficient in these two songbird species.

Lyme borreliosis.

Lyme borreliosis is a tick-borne disease that predominantly occurs in temperate regions of the northern hemisphere and is primarily caused by the bacterium Borrelia burgdorferi in North America and Borrelia afzelii or Borrelia garinii in Europe and Asia. Infection usually begins with an expanding skin lesion, known as erythema migrans (referred to as stage 1), which, if untreated, can be followed by early disseminated infection, particularly neurological abnormalities (stage 2), and by late infection, especially arthritis in North America or acrodermatitis chronica atrophicans in Europe (stage 3). However, the disease can present with any of these manifestations. During infection, the bacteria migrate through the host tissues, adhere to certain cells and can evade immune clearance. Yet, these organisms are eventually killed by both innate and adaptive immune responses and most inflammatory manifestations of the infection resolve. Except for patients with erythema migrans, Lyme borreliosis is diagnosed based on a characteristic clinical constellation of signs and symptoms with serological confirmation of infection. All manifestations of the infection can usually be treated with appropriate antibiotic regimens, but the disease can be followed by post-infectious sequelae in some patients. Prevention of Lyme borreliosis primarily involves the avoidance of tick bites by personal protective measures.

Comparison of the lifetime host-to-tick transmission between two strains of the Lyme disease pathogen Borrelia afzelii.

BACKGROUND: Transmission from the vertebrate host to the arthropod vector is a critical step in the life-cycle of any vector-borne pathogen. How the probability of host-to-vector transmission changes over the duration of the infection is an important predictor of pathogen fitness. The Lyme disease pathogen Borrelia afzelii is transmitted by Ixodes ricinus ticks and establishes a chronic infection inside rodent reservoir hosts. The present study compares the temporal pattern of host-to-tick transmission between two strains of B. afzelii. METHODS: Laboratory mice were experimentally infected via tick bite with one of two strains of B. afzelii: A3 and A10. Mice were repeatedly infested with pathogen-free larval Ixodes ricinus ticks over a period of 4 months. Engorged larval ticks moulted into nymphal ticks that were tested for infection with B. afzelii using qPCR. The proportion of infected nymphs was used to characterize the pattern of host-to-tick transmission over time. RESULTS: Both strains of B. afzelii followed a similar pattern of host-to-tick transmission. Transmission decreased from the acute to the chronic phase of the infection by 16.1 and 29.3% for strains A3 and A10, respectively. Comparison between strains found no evidence of a trade-off in transmission between the acute and chronic phase of infection. Strain A10 had higher lifetime fitness and established a consistently higher spirochete load in nymphal ticks than strain A3. CONCLUSION: Quantifying the relationship between host-to-vector transmission and the age of infection in the host is critical for estimating the lifetime fitness of vector-borne pathogens.

Functional and Genomic Architecture of Borrelia burgdorferi-Induced Cytokine Responses in Humans.

Despite the importance of immune variation for the symptoms and outcome of Lyme disease, the factors influencing cytokine production during infection with the causal pathogen Borrelia burgdorferi remain poorly understood. Borrelia infection-induced monocyte- and T cell-derived cytokines were profiled in peripheral blood from two healthy human cohorts of Western Europeans from the Human Functional Genomics Project. Both non-genetic and genetic host factors were found to influence Borrelia-induced cytokine responses. Age strongly impaired IL-22 responses, and genetic studies identified several independent QTLs that impact Borrelia-induced cytokine production. Genetic, transcriptomic, and functional validation studies revealed an important role for HIF-1α-mediated glycolysis in the cytokine response to Borrelia. HIF-1α pathway activation and increase in glycolysis-derived lactate was confirmed in Lyme disease patients. In conclusion, functional genomics approaches reveal the architecture of cytokine production induced by Borrelia infection of human primary leukocytes and suggest a connection between cellular glucose metabolism and Borrelia-induced cytokine production.

Emerging tick-borne infections in mainland China: an increasing public health threat.

Since the beginning of the 1980s, 33 emerging tick-borne agents have been identified in mainland China, including eight species of spotted fever group rickettsiae, seven species in the family Anaplasmataceae, six genospecies in the complex Borrelia burgdorferi sensu lato, 11 species of Babesia, and the virus causing severe fever with thrombocytopenia syndrome. In this Review we have mapped the geographical distributions of human cases of infection. 15 of the 33 emerging tick-borne agents have been reported to cause human disease, and their clinical characteristics have been described. The non-specific clinical manifestations caused by tick-borne pathogens present a major diagnostic challenge and most physicians are unfamiliar with the many tick-borne diseases that present with non-specific symptoms in the early stages of the illness. Advances in and application of modern molecular techniques should help with identification of emerging tick-borne pathogens and improve laboratory diagnosis of human infections. We expect that more novel tick-borne infections in ticks and animals will be identified and additional emerging tick-borne diseases in human beings will be discovered.

Borrelia burgdorferi sensu stricto and Borrelia afzelii: Population structure and differential pathogenicity.

MultiLocus sequence typing (MLST) is considered a powerful method to unveil relationships within bacterial populations and it constitutes an economical and fast alternative to whole genome sequencing. We used this method to understand whether there are differences in human pathogenicity within and between different Borrelia burgdorferi sensu lato species. Therefore, 136 strains from human patients or ticks from Europe were included in MLST analyses. The scheme employed used eight chromosomally located housekeeping genes (i.e. clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA). We investigated Borrelia afzelii, one of the predominant species in Europe, and B. burgdorferi sensu stricto (s.s.), because it allowed comparative analysis to strains from the USA. We typed 113 patient isolates as well as 23 tick isolates. For further comparative purposes an additional 746 strains from Europe and the USA were included from the MLST website http://borrelia.mlst.net. We observed an overlap of the B. burgdorferi s.s. populations from Europe and the USA isolated from human patients while there was no overlap of the populations found in tick vectors. Further results indicate that B. afzelii was significantly less associated with disseminated infection than B. burgdorferi s.s. and that B. burgdorferi s.s. from Europe caused neuroborreliosis to a significantly greater extent than B. afzelii or B. burgdorferi s.s. in the USA. Our data suggest that there may be an evolutionary basis of differential interspecies pathogenicity in Borrelia. This was not evident within Borrelia species: we found the same sequence types in patients with disseminated or localized symptoms when the number of strains was sufficiently high. We hypothesize that the finding that B. burgdorferi s.s. in Europe is much more associated with neuroborreliosis than in the USA maybe linked to factor(s) related to the human host, the tick vector or the bacterium itself (e.g. plasmid content and structure).

Within-host competition between Borrelia afzelii ospC strains in wild hosts as revealed by massively parallel amplicon sequencing.

Infections frequently consist of more than one strain of a given pathogen. Experiments have shown that co-infecting strains often compete, so that the infection intensity of each strain in mixed infections is lower than in single strain infections. Such within-host competition can have important epidemiological and evolutionary consequences. However, the extent of competition has rarely been investigated in wild, naturally infected hosts, where there is noise in the form of varying inoculation doses, asynchronous infections and host heterogeneity, which can potentially alleviate or eliminate competition. Here, we investigated the extent of competition between Borrelia afzelii strains (as determined by ospC genotype) in three host species sampled in the wild. For this purpose, we developed a protocol for 454 amplicon sequencing of ospC, which allows both detection and quantification of each individual strain in an infection. Each host individual was infected with one to six ospC strains. The infection intensity of each strain was lower in mixed infections than in single ones, showing that there was competition. Rank-abundance plots revealed that there was typically one dominant strain, but that the evenness of the relative infection intensity of the different strains in an infection increased with the multiplicity of infection. We conclude that within-host competition can play an important role under natural conditions despite many potential sources of noise, and that quantification by next-generation amplicon sequencing offers new possibilities to dissect within-host interactions in naturally infected hosts.

Complete genome sequence of Borrelia afzelii K78 and comparative genome analysis.

The main Borrelia species causing Lyme borreliosis in Europe and Asia are Borrelia afzelii, B. garinii, B. burgdorferi and B. bavariensis. This is in contrast to the United States, where infections are exclusively caused by B. burgdorferi. Until to date the genome sequences of four B. afzelii strains, of which only two include the numerous plasmids, are available. In order to further assess the genetic diversity of B. afzelii, the most common species in Europe, responsible for the large variety of clinical manifestations of Lyme borreliosis, we have determined the full genome sequence of the B. afzelii strain K78, a clinical isolate from Austria. The K78 genome contains a linear chromosome (905,949 bp) and 13 plasmids (8 linear and 5 circular) together presenting 1,309 open reading frames of which 496 are located on plasmids. With the exception of lp28-8, all linear replicons in their full length including their telomeres have been sequenced. The comparison with the genomes of the four other B. afzelii strains, ACA-1, PKo, HLJ01 and Tom3107, as well as the one of B. burgdorferi strain B31, confirmed a high degree of conservation within the linear chromosome of B. afzelii, whereas plasmid encoded genes showed a much larger diversity. Since some plasmids present in B. burgdorferi are missing in the B. afzelii genomes, the corresponding virulence factors of B. burgdorferi are found in B. afzelii on other unrelated plasmids. In addition, we have identified a species specific region in the circular plasmid, cp26, which could be used for species determination. Different non-coding RNAs have been located on the B. afzelii K78 genome, which have not previously been annotated in any of the published Borrelia genomes.

Enfermedad de Lyme / Lyme disease

La enfermedad de Lyme (EL) es un proceso multisistémico, de distribución universal, provocado porBorrelia burgdorferi sensu lato (s.l.) y transmitido por garrapatas duras. De hecho, es la enfermedad transmitida por garrapatas más frecuente del hemisferio norte. En España la transmite la garrapataIxodes ricinus y la genoespecie de B. burgdorferi s.l. mayormente implicada es Borrelia garinii. A la EL se la conoce como "el último gran imitador", por el amplio espectro clínico que puede provocar. Salvo en el caso de eritema migratorio (patognomónico de la enfermedad), el resto de manifestaciones clínicas deben confirmarse mediante pruebas microbiológicas.Esta revisión pretende proporcionar a los lectores una visión actual sobre la etiología, epidemiología, manifestaciones clínicas, diagnóstico de laboratorio y tratamiento de la enfermedad en nuestro medio. Se resaltan aspectos polémicos originados por la utilización de pruebas microbiológicas no validadas que están siendo utilizadas sin rigor científico (AU)

Lyme disease (LD) is a worldwide-distributed multisystemic process caused by Borrelia burgdorferisensu lato (s.l.) and transmitted by hard ticks. In fact, it is the most common tick-borne infectious disease in the northern hemisphere. In Spain it is transmitted by Ixodes ricinus ticks and Borrelia garinii is the genoespecies of B. burgdorferi s.l. mostly involved in our area. LD is known as "the last great imitator" due to the broad clinical spectrum that may cause. Except in the case of erythema migrans (pathognomonic feature of the disease), the remaining clinical manifestations should be confirmed using microbiological tests.This review is intended to provide readers a current vision of the etiology, epidemiology, clinical manifestations, laboratory diagnosis and treatment of Lyme disease in our environment. Controversial aspects arising from the use of non-validated microbiological tests that are being used without scientific rigor are highlighted (AU)