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Lyme disease is a tick-transmitted illness caused by Borrelia burgdorferi sensu lato (s.l.), a group of spirochetes with at least three human pathogenic species, B. burgdorferi sensu stricto, B. afzelii and B. garinii. These spirochetes cycle between vertebrate reservoirs, mainly rodents, and ixodid ticks. Both terrestrial birds and seabirds can be infected with B. burgdorferi s.l. but the function of birds as reservoirs is largely unknown, even though they are potentially important epidemiologically due to their ability to carry ectoparasites and microorganisms over long distances. This thesis describes the role of birds in Lyme disease Borrelia biology in general and Borrelia ecology and epidemiology in particular. B. burgdorferi s.l. has previously been detected in the seabird tick Ixodes uriae and an enzootic Borrelia cycle distinct from terrestrial Borrelia cycles has been described. In this study B. garinii was isolated from the proposed seabird reservoirs and the tick I. uriae infesting them. The strains isolated did not show evident differences from human pathogenic B. garinii strains, indeed 7/8 strains had an ospC allele associated with Borrelia causing disseminated Lyme disease. Antibodies against B. burgdorferi s.l. were detected in people frequently bitten by I. uriae. Thus the marine enzootic Borrelia cycle may be a risk for humans, either by direct transfer of the spirochete from /. uriae or via introduction of Borrelia into a terrestrial enzootic Borrelia cycle. In order to investigate the role of passerine (Passeriformes) birds as amplification hosts in the terrestrial Borrelia cycle, experimental infections of canary finches (Serinus canaria) and redwing thrushes (Turdus iliacus) were carried out. The result showed that B. burgdorferi s.l. can persist for several months in passerine birds and the infection in redwing thrushes can be reactivated in response to migration. Thus, birds may be more infectious to ticks during their migration and therefore important long-range disseminators of B. burgdorferi s.l. Migration in birds is associated with elevated stress hormones that in turn can cause reactivation of latent infections. Lyme disease in humans could perhaps be activated when the immune response is modulated by stress. Herein I describe a patient with a stress activated latent Borrelia infection, which supports this hypothesis. The seabird tick I. uriae has a circumpolar distribution in both the northern and southern hemispheres and in this study identical B. garinii flagellin gene (flaB) sequences were detected in I. uriae from these hemispheres, indicating a transequatorial transport of B. garinii. Parsimony analysis of I. uriae ITS2 and 16S rDNA sequences suggested that northern and southern I. uriae might be reproductively separated. Therefore passive transport of infected ticks between the polar regions is unlikely and instead seabirds probably carry an active Borrelia infection during their migration. In conclusion, this work shows that migrating seabirds and passerine birds probably are important for the long-range dispersal of B. burgdorferi s.l., and that this mechanism of dispersal could be important for the distribution of human Lyme disease. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 2001, härtill 6 uppsatser</p> / digitalisering@umu

Many zoonotic pathogens of concern to human and veterinary health are maintained in the environment within small mammal reservoirs and vectored to new hosts by ectoparasitic arthropods. While the ecological relationships among small mammals, ectoparasites, and disease-causing symbiotic microorganisms are important to these dynamics, little is known about them across much of North America. The sylvatic cycle of Borrelia burgdorferi, the etiologic agent of Lyme disease, is of particular interest because Lyme disease is the most common vector-borne disease of humans in the United States. However, cases of Lyme disease are primarily confined to the northeastern and Midwestern United States, with only sporadic cases extending into the southeast. As a result, much of what is known of the ecology of Lyme disease comes from studies conducted in those regions. The goal of this study was to examine the ecological dynamics of the B. burgdorferi/vector/reservoir system in south-central Kentucky and gain insight into the relative paucity of Lyme disease in Kentucky. Small mammals were captured using live traps in three 200x50 m trapping grids within Western Kentucky University’s Green River Preserve from November 2014-October 2015. Captured small mammals were identified to species and standard measurements were recorded. Ectoparasites were removed and retained for identification. Collected blood and tissue were examined for B. burgdorferi DNA by polymerase chain reaction with primers specific to the OspA gene. The Bray-Curtis dissimilarity index, Schnabel population estimates, and the Shannon-Wiener diversity index were used to assess the structure of the small mammal communities. Parasite infestation was low but was affected by age and sex of the host, site, and season in different parasite taxa. Infestation by Ixodes scapularis, the primary vector for B. burgdorferi, was uncommon and prevalence of B. burgdorferi in blood was similar to the lowest prevalence previously observed in the Lyme disease endemic regions. We found that life history characteristics of hosts and ectoparasites drive their associations. We also suggest that the lack of an efficient vector for B. burgdorferi is the likely explanation for the few reported cases of Lyme disease in Kentucky.

<p>In Europe, Lyme disease<em> </em>is caused by the species <em>Borrelia (B.) burgdorferi</em> sensu stricto,<em> B. garinii </em>and <em>B. afzelii.</em> The disease is the most common vector-borne infection in Europe and the United States,<em> </em>and the resulting manifestation can involve the skin, nervous system, heart and joints. The symptoms that arise are associated with the <em>Borrelia </em>species causing the infection. The species most associated with neuroborreliosis is <em>B. garinii</em> whilst <em>B. burgdorferi </em>sensu stricto is associated with arthritis and <em>B. afzelii </em>is associated with dermatological symptoms. Lyme disease normally has three phases in untreated patients. The first phase is characterised by erythema migrans, a reddening of the skin around the area of the tick bite. If the disease develops to the second phase the patient will suffer from neuroborreliosis which is characterised by neurological symptoms such as headache and peripheral facial paralysis. Cerebrospinal fluid (CSF) analysis is used to diagnose neuroborreliosis. The diagnosis is complicated by variations between the different <em>Borrelia</em> species and that many healthy individuals have antibodies directed against <em>Borrelia</em>. Antibodies in CSF can be found in different diseases. The antibodies can be produced in the central nervous system or come across the blood-brain barrier and thus derive originally from the blood. By measuring the concentration of total albumin in serum and in CSF it can be determined if the antibodies present in the CSF have been produced in the central nervous system or if they originate from the blood. The typical manifestation in the last phase of Lyme disease is severe arthritis. The aim of this examination project was to compare two ELISAs for detection of antibodies directed to <em>Borrelia</em>. Indirect ELISAs from DAKO and Euroimmun were compared for the diagnosis of neuroborreliosis in 100 individuals. <em>Borrelia </em>specific antibodies of class IgM or IgG were found in 16 of 100 patients by DAKO’s ELISA and in 20 of the same 100 patients by Euroimmun’s ELISA. The reason that Euroimmun’s method detected more cases of neuroborreliosis is probably that this method detects antibodies directed to all three pathological species of <em>Borrelia </em>while DAKO’s method only detects antibodies directed to <em>B. burgdorferi</em>. In conclusion, this study indicates that Euroimmun’s method to detect antibodies of class IgM and IgG directed to <em>Borrelia </em>is superior to DAKO’s method. The obtained results were confirmed by Western blot analysis which gave results in accordance with those of Euroimmun’s ELISA.</p>

The Lyme disease spirochete, B. burgdorferi is atypical in that a large portion of its genome is in the form of plasmids. Many of the plasmid-carried genes form extensive paralogous gene families and encode outer-surface proteins. In this report we have assessed the humoral immune response to proteins belonging to the paralogous protein family, family 163. We have cloned and expressed BBP39, BBO40, BBQ47 and BBN39 and used these recombinant proteins to monitor the temporal nature of the antibody response to these antigens during experimental infection of mice. The immunodominant regions of each protein have also been assessed through immunoblot analyses of a series of truncations of each protein. These analyses have led to the delineation of the targets of the antibody response during infection and of the specificity of the antibody response to family 163 proteins. In addition, we quantified the expression of each gene using real time RT-PCR.

Lyme disease (LD) is the leading arthropod-borne disease in North America with 300-600,000 cases each year. There are currently no approved human LD vaccines. Outer surface protein C (OspC) has emerged as a leading vaccine candidate and an attractive diagnostic marker due to its antigenicity and expression early in infection. Several chimeric, epitope based OspC derived proteins were generated. The constructs were found to be highly immunogenic in mice and vaccination induced complement-dependent bactericidal antibodies. These results suggest that a broadly protective polyvalent OspC epitope based vaccine can be produced. Currently, LD diagnostic approaches are unreliable and unable to differentiate between early and late stage disease. An Ab response to OspE family proteins occurs later in infection. The two-Ag diagnostic assay using chimeric OspC proteins and a site-directed mutant of an OspE paralog, accurately differentiated between early and late infection in experimentally infected canines and humans.

Introduction: Lyme disease is caused by the tick-borne spirochete Borrelia burgdorferi. Research has shown that dogs can be used as sentinels for human infection of Lyme disease. The purpose of this 5-year, retrospective study was to determine if there was any evidence that the incidence of canine Lyme disease has increased between 2000 and 2005 in Accomack and Northampton counties. An increased incidence in Lyme disease in dogs may indicate an increased present or future risk of Lyme disease in humans.Methods: Cases of canine Lyme disease were identified via practice invoicing systems and dogs that received doxycycline were entered into the database. Demographic information and the absence or presence of clinical signs such as fever, lameness, articular swelling, lymphadenomegaly, anorexia, general malaise and improvement after antibiotic use were collected. Testing history also was recorded.Results: Cases of canine Lyme disease that met any definition were identified (n=1048). Over the 5-year period the number of positive ELISA test results increased and the frequency of clinical signs decreased. The incidence of disease meeting the practitioner's definition increased until 2004 when the incidence dropped from 105.33 cases per 1,000 dogs to 56.93 cases per 1,000. The incidence of disease based on the study probable definition remained fairly constant with a high in 2002 of 2.94 cases per 1,000 dogs.Discussion: Trends of canine Lyme disease coincided with the introduction and use of the in-house ELISA test. Practitioners could identify more dogs exposed to Borrelia burgdorferi. The areas with the highest frequency of canine cases of Lyme disease also had the highest frequency of human cases reported to the Virginia Department of Health. Further study could identify animals that tested positive and later developed clinical signs. Using dogs as sentinels for human infection allows public health workers to identify endemic areas regardless of human case reports.

The aim of the study was to obtain and elaborate information focused on metamorphoses of Borrelia burgdorferi sensu lato (s.l.) spirochetes. The research included detection of various stress conditions for production of dormant forms of Borrelia burgdorferi s.l. spirochetes in vitro. Subsequently, metamorphoses from dormant to motile stages was observed under favourable conditions. Proper PCR method for primers aimed to detect dormant forms of Borrelia was delevoped. The infectious potential of dormant spirochetes of Borrelia burgdorferi sensu stricto (s.s.) complex was observed in vivo. Transformations of spirochetes have also been observed in real time and individual stages have been recorded.

O estudo objetivou realizar um levantamento de doenças transmitidas por carrapatos em amostras de humanos e animais domésticos oriundos do Estado do Espírito Santo. Foram estudadas as Riquétsioses, Erliquiose, Babesiose, Borreliose, e especificamente em cães a Hepatozoonose canina. Três expedições científicas foram realizadas, onde foram coletadas amostras de sangue de humanos (n=201), cães (n=92) e eqüídeos (n=27). As amostras foram testadas utilizando-se os ensaios de Imunofluorescência Indireta (RIFI) e ELISA Indireto, dependendo do antígeno de eleição. A Reação em Cadeia de Polimerase (PCR) foi realizada utilizando primers específicos para os gêneros dos agentes pesquisados. Foi possível concluir que os municípios estudados podem ser considerados endêmicos para as zoonoses pesquisadas / This study aimed to perform a survey on tick-borne diseases in blood samples from humans and domestic animals from the State of Espírito Santo. The following diseases were studied: Rickettsiosis, Ehrlichiosis, Babesiosis, Borreliosis, and specifically in dogs, Canine Hepatozoonosis. Three scientific expeditions were performed, where blood samples from humans (n=201), dogs (n=92) and equids (n=27) were collected. Samples were tested using Indirect Immunofluorescence Assays (IFA) and Indirect ELISA, depending on the antigen. Polymerase Chain Reactions (PCR) were performed using specific primers to the genera of the surveyed agents. We concluded that the studied municipalities can be considered endemic areas to the surveyed zoonosis

O estudo objetivou realizar um levantamento de doenças transmitidas por carrapatos em amostras de humanos e animais domésticos oriundos do Estado do Espírito Santo. Foram estudadas as Riquétsioses, Erliquiose, Babesiose, Borreliose, e especificamente em cães a Hepatozoonose canina. Três expedições científicas foram realizadas, onde foram coletadas amostras de sangue de humanos (n=201), cães (n=92) e eqüídeos (n=27). As amostras foram testadas utilizando-se os ensaios de Imunofluorescência Indireta (RIFI) e ELISA Indireto, dependendo do antígeno de eleição. A Reação em Cadeia de Polimerase (PCR) foi realizada utilizando primers específicos para os gêneros dos agentes pesquisados. Foi possível concluir que os municípios estudados podem ser considerados endêmicos para as zoonoses pesquisadas / This study aimed to perform a survey on tick-borne diseases in blood samples from humans and domestic animals from the State of Espírito Santo. The following diseases were studied: Rickettsiosis, Ehrlichiosis, Babesiosis, Borreliosis, and specifically in dogs, Canine Hepatozoonosis. Three scientific expeditions were performed, where blood samples from humans (n=201), dogs (n=92) and equids (n=27) were collected. Samples were tested using Indirect Immunofluorescence Assays (IFA) and Indirect ELISA, depending on the antigen. Polymerase Chain Reactions (PCR) were performed using specific primers to the genera of the surveyed agents. We concluded that the studied municipalities can be considered endemic areas to the surveyed zoonosis