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Branda J, Lemieux J, Blair L, et al.
AbstractBackgroundLaboratory confirmation of early Lyme borreliosis (LB) is challenging. Serology is insensitive during the first days to weeks of infection, and blood PCR offers similarly poor performance. Here, we demonstrate that detection of Borrelia burgdorferi (B.b.) cell-free DNA (cfDNA) in plasma can improve diagnosis of early LB.MethodsB.b. detection in plasma samples using unbiased metagenomic cfDNA sequencing performed by a commercial laboratory (Karius Inc.) was compared with serology and blood PCR in 40 patients with physician-diagnosed EM, 28 of whom were confirmed to have LB by skin biopsy culture (N=18), seroconversion (N=2) or both (N=8). B.b. sequence analysis was performed using investigational detection thresholds, different from Karius’ clinical test.ResultsB.b.cfDNA was detected in 18/28 patients (64%) with laboratory-confirmed EM. In comparison, sensitivity of acute-phase serology using modified two-tiered testing (MTTT) was 50% (P=0.45); sensitivity of blood PCR was 7% (P=0.0002). Combining B.b.cfDNA detection and MTTT increased diagnostic sensitivity to 86%, significantly higher than either approach alone (P≤0.04). B.b.cfDNA sequences matched precisely with strain-specific sequence generated from the same individual’s cultured B.b. isolate. B.b.cfDNA was not observed at any level in plasma from 684 asymptomatic ambulatory individuals. Among 3000 hospitalized patients tested as part of clinical care, B.b.cfDNA was detected in only two individuals, both of whom had clinical presentations consistent with LB.ConclusionsThis is the first report of B.b.cfDNA detection in early LB and a demonstration of potential diagnostic utility. The combination of B.b.cfDNA detection and acute-phase MTTT improves clinical sensitivity for diagnosis of early LB.
Yi-Pin Lin, Maria A. Diuk-Wasser, Brian Stevenson, Peter Kraiczy
Lyme disease is the most common vector-borne disease in the northern hemisphere and is caused by spirochetes of the Borrelia burgdorferi sensu lato complex. Lyme borreliae infect diverse vertebrate reservoirs without triggering apparent manifestations in these animals; however, Lyme borreliae strains differ in their reservoir hosts. The mechanisms that drive those differences are unknown. To survive in vertebrate hosts, Lyme borreliae require the ability to escape from host defense mechanisms, in particular complement.
The diagnosis of human anaplasmosis remains elusive and is probably often missed. This case report highlights the efficacy of molecular diagnostic techniques.
We would like to report the case of a 74-year-old man who was admitted to hospital because of a high fever, marked chills, transient diplopic images and vertigo, 6 weeks after multiple tick bites. The laboratory results showed mild anemia, marked thrombocytopenia and leukopenia and a moderately elevated C-reactive protein. The initial serology seemed to indicate an active infection with Borrelia spp., and Anaplasma phagocytophilum was detected in peripheral blood by polymerase chain reaction (PCR) and subsequent sequencing. The patient received intravenous ceftriaxone for 14 days and oral doxycycline for 4 weeks and made a fast and complete recovery.
While human anaplasmosis has been reported very rarely in Austria, it should be considered as a differential diagnosis in febrile patients with low leukocyte and platelet counts with elevated levels of C-reactive protein after exposure to tick bites. Molecular detection of A. phagocytophilum is the technique of choice allowing rapid and reliable diagnosis.
Eckman E, Clausen D, Herdt A, et al.
AbstractBackgroundDemonstration of intrathecal production of Borrelia-specific antibodies (ITAb) is considered the most specific diagnostic marker of Lyme neuroborreliosis (LNB). Limitations include delayed detectabilty in early infection and continued presence long after successful treatment. Markers of active inflammation – increased CSF leukocytes, protein and CXCL13 – provide nonspecific markers of active infection. To assess the utility of CSF CXCL13, we measured its concentration in 132 patients with a broad spectrum of neuroinflammatory disorders, including LNB.MethodsCSF CXCL13 was measured by immunoassay. Spearman’s rank correlation test was performed to explore its relationship to conventional markers of neuroinflammation and Borrelia-specific ITAb production.ResultsIn non-LNB neuroinflammatory disorders, CSF CXCL13 elevation correlated with CSF IgG synthesis and leukocyte count. In LNB, CXCL13 concentration was far greater than expected from overall CSF IgG synthesis, and correlated with Borrelia-specific ITAb synthesis. Median CSF CXCL13 concentration in ITAb-positive LNB patients was >500 times greater than in any other group.ConclusionsIntrathecal CXCL13 and IgG production are closely inter-related. CXCL13 is disproportionately increased in “definite LNB,” defined as having demonstrable Borrelia-specific ITAb, but not “probable LNB,” without ITAb. This disproportionate increase may help identify patients with very early infection, those with active vs. treated LNB, or help differentiate ITAb-defined active LNB from other neuroinflammatory disorders. However, its reported specificity is closely related to the diagnostic requirement for ITAb. It may add little specificity to the demonstration of a pleocytosis or increased overall or specific IgG production in the CSF.
Thompson, C., Mason, C., Parrilla, S., Ouyang, Z.
Borrelia burgdorferi encodes a functional homolog of canonical Lon protease termed Lon-2. In addition, B. burgdorferi encodes a second Lon homolog called Lon-1. Recent studies suggest that Lon-1 may function differently from the prototypical Lon protease. However, the function of Lon-1 in B. burgdorferi biology remains virtually unknown. Particularly, the contribution of Lon-1 to B. burgdorferi fitness and infection remains hitherto unexplored. Herein, we show that Lon-1 plays a critical role in the infection of B. burgdorferi in a mammalian host. We found that lon-1 was highly expressed during animal infection, implying an important function of this protein in bacterial infection. We further generated a lon-1 deletion mutant and an isogenic complemented strain. Relative to that of the wild-type strain, the infectivity of the mutant was severely attenuated in a murine infection model. Our data also showed that the mutant displayed growth defects in regular BSK-II medium. Furthermore, bacterial resistance to osmotic stress was markedly reduced when lon-1 was inactivated. When exposed to tert-butyl hydroperoxide, survival of the lon-1 mutant was impaired. In addition, production of several virulence factors such as BosR, RpoS, and OspC was elevated in the mutant. These phenotypes were restored when lon-1 mutation was complemented. Finally, we created a lon-1(S714A) mutant and found that this mutant failed to infect mice, suggesting that the proteolytic activity of Lon-1 is essential for bacterial infection. Taken together, these results demonstrate that Lon-1 is required by B. burgdorferi to infect animal hosts and to cope with environmental stresses.
V. Muigg et al.
Marcinkiewicz, A. L., Lieknina, I., Yang, X., Lederman, P. L., Hart, T. M., Yates, J., Chen, W.-H., Bottazzi, M. E., Mantis, N. J., Kraiczy, P., Pal, U., Tars, K., Lin, Y.-P.
The spirochete Borrelia burgdorferi sensu lato is the causative agent of Lyme disease (LD). The spirochetes produce the CspZ protein that binds to a complement regulator, factor H (FH). Such binding downregulates activation of host complement to facilitate spirochete evasion of complement killing. However, vaccination with CspZ does not protect LD infection. In this study, we demonstrated that immunization with CspZ-YA, a CspZ mutant protein with no FH-binding activity, protected mice from infection by several spirochete genotypes introduced via tick feeding. We found that the sera from CspZ-YA-vaccinated mice more efficiently eliminated spirochetes and blocked CspZ FH-binding activity than sera from CspZ-immunized mice. We also found vaccination with CspZ, but not CspZ-YA, triggered the production of anti-FH antibodies, justifying CspZ-YA as a LD vaccine candidate. The mechanistic and efficacy information derived from this study provides insights into the development of a CspZ-based LD vaccine.
Ruiyan Zhang, Ting Gong, Teng Chen, Ning Zhang, Faming Miao, Qi Chen, Ye Feng, Lu Ji, Jinghui Zhao
We read with interest the recently published article titled "Seroprevalence of Lyme borreliosis in Finland 50 years ago" .We applaud the authors for studyingthe Lyme borreliosis (LB) seroprevalence in Finland in the 1960s and 1970s through evaluation of IgG against Borrelia burgdorferiin historical serum samples. Despite its scientific and comprehensive, some technical issues should be discussed.
Strle K, Strle F.
Lyme borreliosisoutcomeposttreatment Lyme disease symptomsBorrelia burgdorferi sensu latobiomarkers
Quentin Bernard, Antoine Grillon, Cédric Lenormand, Laurence Ehret-Sabatier, Nathalie Boulanger
The skin plays a key role in vector-borne diseases because it is the site where the arthropod coinoculates pathogens and its saliva. Lyme borreliosis, particularly well investigated in this context, is a multisystemic infectious disease caused by Borrelia burgdorferi sensu lato and transmitted by the hard tick Ixodes. Numerous in vitro studies were conducted to better understand the role of specific skin cells and tick saliva in host defense, vector feeding, and pathogen transmission. The skin was also evidenced in various animal models as the site of bacterial multiplication and persistence.
Cuellar, J., Astrand, M., Elovaara, H., Pietikäinen, A., Siren, S., Liljeblad, A., Guedez, G., Salminen, T. A., Hytönen, J.
Borrelia burgdorferi sensu lato (sl), the causative agent of the tick-borne Lyme borreliosis (LB), has a limited metabolic capacity and needs to acquire nutrients, such as amino acids, fatty acids, and nucleic acids, from the host environment. Using X-ray crystallography, liquid chromatography-mass spectrometry, microscale thermophoresis, and cellular localization studies, we show that Basic membrane protein D (BmpD) is a periplasmic substrate-binding protein of an ABC transporter system binding to purine nucleosides. Nucleosides are essential for bacterial survival in the host organism and these studies suggest a key role for BmpD in the purine salvage pathway of B. burgdorferi sl. As B. burgdorferi sl lacks the enzymes required for de novo purine synthesis, BmpD may play a vital role in ensuring access to the purines needed for sustaining an infection in the host. Further, we show that although human LB patients develop anti-BmpD antibodies, immunization of mice with BmpD does not confer protection against B. burgdorferi sl infection.
Nayak, A., Schüler, W., Seidel, S., Gomez, I., Meinke, A., Comstedt, P., Lundberg, U.
The development of vaccines for prevention of diseases caused by pathogenic species can encounter major obstacles if high sequence diversity is observed between individual strains. Therefore, the development might be restricted either to conserved antigens, which often are rare, or to multivalent vaccines, which renders the production more costly and cumbersome. In light of this complexity, we applied a structure-based surface shaping approach for the development of a Lyme borreliosis (LB) vaccine suitable for the USA and Europe. The surface of the C-terminal fragment of outer surface protein A (OspA) was divided into distinct regions mainly based on binding sites of monoclonal antibodies. In order to target the six clinically most relevant OspA serotypes (ST) in a single protein, exposed amino acids of the individual regions were exchanged to corresponding amino acids of a chosen OspA serotype. Six chimeric proteins were constructed and based on their immunogenicity four of these chimeras were tested in mouse challenge models. Significant protection could be demonstrated for all four proteins following challenge with infected ticks (OspA ST1, OspA ST2, and OspA ST4), as well as with in vitro grown spirochetes (OspA ST1 and OspA ST5). Two of the chimeric proteins were linked to form a fusion protein, which provided significant protection against in vitro grown spirochetes (OspA ST1) and infected ticks (OspA ST2). This article presents the proof-of-concept study for a multivalent OspA vaccine targeting a wide range of pathogenic LB Borrelia species with a single recombinant antigen for prevention of Lyme borreliosis.
Célia Scherelle Boumbanda Koyo, Sandrine Lydie Oyegue-Liabagui, Oleg Mediannikov, Sébastien Cortaredona, Lady Charlene Kouna, Didier Raoult, Jean Bernard Lekana-Douki and Florence Fenollar
The epidemiology of febrile illness etiologies is under-explored in resource-poor settings. Establishing a local repertory of microorganisms circulating in blood of febrile and afebrile people is important for physicians. Blood was collected from 428 febrile and 88 afebrile children in Makokou (Gabon) and analyzed using polymerase chain reaction. Plasmodium spp. were the pathogens, which were most detected in febrile children (69.6%; 298/428) and in afebrile children (31.8%; 28/88) (P < 0.0001). Plasmodium falciparum was the most prevalent species in both febrile and afebrile children (66.8% and 27.3%, respectively). No differences were observed between febrile and afebrile children for Plasmodium malariae and Plasmodium ovale (8.2% versus 10.2% and 3.3% versus 3.4%, respectively). Triple infection with P. falciparum, P. malariae, and P. ovale was also detected in 1% of febrile children (4/428). Filariasis due to Mansonella perstans was detected in 10 febrile patients (2.3%), whereas Loa loa was detected in both febrile and afebrile children (1.4% and 2.3%, respectively). Bacterial DNA was detected in only 4.4% (19/428) of febrile children, including 13 (68.4%) who were coinfected with at least one Plasmodium species. These were Haemophilus influenzae (1.6%, 7/428), Streptococcus pneumoniae and Staphylococcus aureus (1.2%, 5/428), and Rickettsia felis (0.9%, 4/428). Coxiella burnetii, Bartonella spp., Borrelia spp., Tropheryma whipplei, Anaplasma spp., Leptospira spp., Streptococcus pyogenes, and Salmonella spp. were not detected. This study also highlights the over-prescription and the overuse of antibiotics and antimalarials. Overall, malaria remains a major health problem in Makokou. Malaria control measures must be reconsidered in this region.
Ndeye Safietou Fall, Nafissatou Diagne, Oleg Mediannikov, Florence Fenollar, Philippe Parola, Cheikh Sokhna, Didier Raoult, Jean-Christophe Lagier
Kristin Boardman, Kyle Rosenke, David Safronetz, Heinz Feldmann and Tom G. Schwan
African multimammate rats, Mastomys natalensis, are widely distributed in sub-Saharan Africa and live in close association with humans. In West Africa, numerous field studies have shown these animals may be naturally infected with the relapsing fever spirochete Borrelia crocidurae, the primary cause of tick-borne relapsing fever in this region of the continent. However, naturally infected individual rats have never been examined over time; therefore, the true host competency of these rats for this spirochete is unknown. Therefore, using animals from an established laboratory colony of M. natalensis, rats were experimentally infected with B. crocidurae and their blood examined to 28 days postinoculation. These animals were highly susceptible to infection and displayed prolonged and cyclic spirochetemias. Our results demonstrate these peridomestic rodents are likely competent hosts for infecting argasid tick vectors and play a primary role in the enzootic cycle for B. crocidurae in West Africa.
Bista S, Singh P, Bernard Q, et al.
AbstractBorrelia burgdorferi conserved gene-products BB0406 and BB0405, members of a common B. burgdorferi paralogous gene family, share 59% similarity. While both gene-products can function as potential porins, only BB0405 is essential for infection. Here we show that, despite sequence homology and co-expression from the same operon, both proteins differ in their membrane localization attributes, antibody accessibility, and immunogenicity in mice. BB0406 is required for spirochete survival in mammalian hosts, particularly for the disseminated infection in distant organs. We identified that BB0406 interacts with laminin, one of the major constituents of the vascular basement membrane, and facilitates spirochete transmigration across host endothelial cell barriers. A better understanding of how B. burgdorferi transmigrates through dermal and tissue vascular barriers and establishes disseminated infections will contribute to the development of novel therapeutics to combat early infection.
Gomes-Solecki M, Arnaboldi P, Backenson P, et al.
AbstractLyme disease, caused by some Borrelia burgdorferi sensu lato, is the most common tick-borne illness in the Northern Hemisphere and the number of cases, and geographic spread, continue to grow. Previously identified B. burgdorferi proteins, lipid immunogens, and live mutants lead the design of canonical vaccines aimed at disrupting infection in the host. Discovery of the mechanism of action of the first vaccine catalyzed the development of new strategies to control Lyme disease that bypassed direct vaccination of the human host. Thus, novel prevention concepts center on proteins produced by B. burgdorferi during tick transit and on tick proteins that mediate feeding and pathogen transmission. A burgeoning area of research is tick immunity as it can unlock mechanistic pathways that could be targeted for disruption. Studies that shed light on the mammalian immune pathways engaged during tick-transmitted B. burgdorferi infection would further development of vaccination strategies against Lyme disease.
The aim of the study is to assess anti-Coxiella burnetii antibodies presence in inhabitants of north-eastern Poland, to assess the risk of Q fever after tick bite and to assess the percentage of co-infection with other pathogens.
The serological study included 164 foresters and farmers with a history of tick bite. The molecular study included 540 patients, hospitalized because of various symptoms after tick bite. The control group consisted of 20 honorary blood donors. Anti-Coxiella burnetii antibodies titers were determined by Coxiella burnetii (Q fever) Phase 1 IgG ELISA (DRG International Inc. USA). PCR was performed to detect DNA of C. burnetii, Borrelia burgdorferi and Anaplasma phagocytophilum.
Anti-C. burnetii IgG was detected in six foresters (7.3%). All foresters with the anti-C. burnetii IgG presence were positive toward anti-B. burgdorferi IgG and anti-TBE (tick-borne encephalitis). Anti-C. burnetii IgG was detected in five farmers (6%). Four farmers with anti-C. burnetii IgG presence were positive toward anti-B. burgdorferi IgG and two with anti-TBE. Among them one was co-infected with B. burgdorferi and TBEV. Correlations between anti-C. burnetii IgG and anti-B. burgdorferi IgG presence and between anti-C. burnetii IgG presence and symptoms of Lyme disease were observed. C. burnetii DNA was not detected in any of the 540 (0%) patients.
C. burnetii is rarely transmitted by ticks, but we proved that it is present in the environment, so it may be a danger to humans. The most common co-occurrence after tick bite concerns C. burnetii and B. burgdorferi.
A. J. Henningsson et al.
Lyme borreliosis (LB) is a tick-borne disease caused by spirochetes belonging to the Borrelia burgdorferi sensu lato species. Due to a variety of clinical manifestations, diagnosing LB can be challenging, and laboratory work-up is usually required in case of disseminated LB. However, the current standard of diagnostics is serology, which comes with several shortcomings. Antibody formation may be absent in the early phase of the disease, and once IgG-seroconversion has occurred, it can be difficult to distinguish between a past (cured or self-cleared) LB and an active infection. It has been postulated that novel cellular tests for LB may have both higher sensitivity earlier in the course of the disease, and may be able to discriminate between a past and active infection.
VICTORY is a prospective two-gate case-control study. We strive to include 150 patients who meet the European case definitions for either localized or disseminated LB. In addition, we aim to include 225 healthy controls without current LB and 60 controls with potentially cross-reactive conditions. We will perform four different cellular tests in all of these participants, which will allow us to determine sensitivity and specificity. In LB patients, we will repeat cellular tests at 6 weeks and 12 weeks after start of antibiotic treatment to assess the usefulness as ‘test-of-cure’. Furthermore, we will investigate the performance of the different cellular tests in a cohort of patients with persistent symptoms attributed to LB.
This article describes the background and design of the VICTORY study protocol. The findings of our study will help to better appreciate the utility of cellular tests in the diagnosis of Lyme borreliosis.
NL7732 (Netherlands Trial Register, trialregister.nl).
Joris Koetsveld, Alexander E. Platonov, Konstantin Kuleshov, Alex Wagemakers, Dieuwertje Hoornstra, Wim Ang, Sandor Szekeres, Gilian L.A. van Duijvendijk, Erol Fikrig, Monica E. Embers, Hein Sprong, Joppe W. Hovius
Borrelia miyamotoi is a relapsing fever Borrelia, transmitted by hard (Ixodes) ticks, which are also the main vector for Borrelia burgdorferi. A widely used test for serodiagnosis of Lyme borreliosis is an EIA based on the C6 peptide of the B. burgdorferi sl VlsE protein. We set out to study C6 reactivity upon infection with B. miyamotoi in a large well-characterized set of Borrelia miyamotoi disease (BMD) patient sera and in experimental murine infection.
Hodzic, E., Imai, D. M., Escobar, E.
A basic feature of infection caused by Borrelia burgdorferi, the etiological agent of Lyme borreliosis, is that persistent infection is the rule in its many hosts. The ability to persist and evade host immune clearance poses a challenge to effective antimicrobial treatment. A link between therapy failure and the presence of persister cells has started to emerge. There is growing experimental evidence that viable, but non-cultivable spirochetes persist following treatment with several different antimicrobial agents. The current study utilized the mouse model to evaluate if persistence occurs following antimicrobial treatment in a disease-susceptible (C3H/HeJ) and disease-resistant (C57BL/6) mouse strain infected with B. burgdorferi strains N40 and B31, to confirm the generality of this phenomena as well as to assess the persisters' clinical relevance. The status of infection was evaluated at 12 and 18-months after treatment. The results demonstrated that persistent spirochetes remain viable for up to 18 months following treatment, as well as being non-cultivable. The phenomenon of persistence in disease-susceptible C3H mice is equally evident in disease-resistant B6 mice, and not unique to any particular B. burgdorferi strain. Results also demonstrate that following antimicrobial treatment, both strains of B. burgdorferi, N40 and B31, lose one or more plasmids. The study demonstrated that non-cultivable spirochetes can persist in a host following antimicrobial treatment for a long time but did not demonstrate their clinical relevance in a mouse model of chronic infection. The clinical relevance of persistent spirochetes beyond 18 months following antimicrobial treatment require further studies in other animal models.
Alice Raffetin, Aurélie Saunier, Kevin Bouiller, Pauline Caraux-Paz, Carole Eldin, Sébastien Gallien, Romain Jouenne, Anna Belkacem, Jérôme Salomon, Olivier Patey, Emilie Talagrand-Reboul, Benoît Jaulhac, Antoine Grillon
Lyme borreliosis (LB) diagnosis currently relies mainly on serological tests and sometimes polymerase chain reaction or culture. However, other biological assays are being developed to try to improve Borrelia-infection diagnosis and/or monitoring.
Basma El Hamzaoui, Maureen Laroche, Yassina Bechah, Jean Michel Bérenger and Philippe Parola
In recent years, bed bugs have reappeared in greater numbers, more frequently, and are biting humans in many new geographic areas. Infestations by these hematophagous insects are rapidly increasing worldwide. Borrelia recurrentis, a spirochete bacterium, is the etiologic agent of louse-borne relapsing fever. The known vectors are body lice, Pediculus humanus humanus. However, previous studies have suggested that bed bugs might also be able to transmit this bacterium. Adult Cimex lectularius were artificially infected with a blood meal mixed with bacterial suspension of B. recurrentis. They were subsequently fed with pathogen-free human blood until the end of the experiment. Bed bugs and feces were collected every 5 days to evaluate the capacity of bed bugs to acquire and excrete viable B. recurrentis using molecular biology, cultures, fluorescein diacetate and immunofluorescence assays. The feces collected on the day 5 and 10 postinfection contained viable bacteria. Immunofluorescence analysis of exposed bed bugs showed the presence of B. recurrentis in the digestive tract, even in bed bugs collected on day 20 after infection. Like human body lice, bed bugs can acquire, maintain, and excrete viable B. recurrentis that might infect humans through skin lesions. This preliminary work suggests that bed bugs might be competent vectors of B. recurrentis. Because bed bugs and body lice may share the same ecological niches, the role of bed bugs in transmitting recurrent fevers deserves further study.
Rogovskyy, A. S., Caoili, S. E. C., Ionov, Y., Piontkivska, H., Skums, P., Tsyvina, V., Zelikovsky, A., Waghela, S. D.
Lyme disease (LD), the most prevalent vector-borne illness in the United States and Europe, is caused by Borreliella burgdorferi (Bb). No vaccine is available for humans. Dogmatically, Bb can establish a persistent infection in the mammalian host (e.g., mice) due to a surface antigen, VlsE. This antigenically variable protein allows the spirochete to continually evade borreliacidal antibodies. However, our recent study has shown that the Bb spirochete is effectively cleared by anti-Bb antibodies of New Zealand White rabbits despite the surface expression of VlsE. Besides homologous protection, the rabbit antibodies also cross-protect against heterologous Bb and significantly reduced pathology of LD arthritis in persistently infected mice. Thus, this finding that NZW rabbits develop a unique repertoire of very potent antibodies targeting the protective surface epitopes, despite abundant VlsE, prompted us to identify specificities of the rabbit protective antibodies and their respective targets. By applying subtractive reverse vaccinology, which involved random peptide phage display libraries coupled with the next generation sequencing and our computational algorithms, repertoires of non-protective (early) and protective (late) rabbit antibodies were identified and directly compared. Consequently, putative surface epitopes that are unique to the rabbit protective sera have been mapped. Importantly, the relevance of newly identified protection-associated epitopes for their surface exposure has been strongly supported by prior empirical studies. This study is significant because it now allows us to systematically test the putative epitopes for their protective efficacy with an ultimate goal of selecting the most efficacious targets for development of a long-awaited LD vaccine.
Mosel, M. R., Carolan, H. E., Rebman, A. W., Castro, S., Massire, C., Ecker, D. J., Soloski, M. J., Aucott, J. N., Eshoo, M. W.
Borrelia burgdorferi is the etiological agent of Lyme disease. In the current study, we used direct detection PCR and electrospray ionization mass spectrometry to monitor and genotype B. burgdorferi from serially collected whole blood specimens from clinically diagnosed early Lyme disease patients before and during 21 days of antibiotic therapy. B. burgdorferi was detected up to three weeks after the initiation of antibiotic treatment with ratios of co-infecting B. burgdorferi genotypes changing over time.
Susan J. Best, Marlene I. Tschaepe, Kim M. Wilson
by Susan J. Best, Marlene I. Tschaepe, Kim M. Wilson
Spirochaetes of the Borrelia burgdorferi sensu lato complex, which includes those that cause Lyme disease, have not been identified in Australia. Nevertheless, Australian patients exist, some of whom have not left the country, who have symptoms consistent with so-called “chronic Lyme disease”. Blood specimens from these individuals may be tested in Australian laboratories and in specialist laboratories outside Australia and sometimes conflicting results are obtained. Such discrepancies cause the patients to question the results from the Australian laboratories and seek assistance from the Australian Government in clarifying why the discrepancies occur. The aim of this study was to determine the level of agreement in results between commonly used B. burgdorferi serology assays in specimens of known status, and between results reported by different laboratories when they use the same serology assay. Five immunoassays and five immunoblots used in Australia and elsewhere were examined for the detection of IgG antibodies to Borrelia burgdorferi sensu lato. Predominantly, archived specimens previously tested for Lyme disease were used for the study and included 639 contributed by seven clinical laboratories located either in Australia or in areas endemic for Lyme disease. Also included were 308 prospectively collected Australian blood donor specimens. All clinical specimens were tested in all 10 assays whereas blood donor specimens were tested in all immunoassays and a subset was tested on immunoblots. With the exception of one immunoblot, the results between the assays agreed with each other in a known positive specimen population ≥ 77% of the time and in a known negative population, 88% of the time or greater. The test results obtained during the study were different from the participating laboratory’s less than 2% of the time when the same assay was used. These findings suggest that discordance in results between laboratories is more likely due to variation in algorithms or in the use of assays with different sensitivities or specificities rather than conflicting results being reported from the same assay in different laboratories. In the known negative population, specificities of the immunoassays ranged between 87.7% and 99.7%. In Australia’s low prevalence population, this would translate to a positive predictive value of < 4%.
Batool, M., Hillhouse, A. E., Ionov, Y., Kochan, K. J., Mohebbi, F., Stoica, G., Threadgill, D. W., Zelikovsky, A., Waghela, S. D., Wiener, D. J., Rogovskyy, A. S.
Borrelia burgdorferi is a tick-borne bacterium responsible for approximately 300,000 annual cases of Lyme disease (LD) in the USA with increasing incidents in other parts of the world. The debilitating nature of LD is mainly attributed to the ability of B. burgdorferi to persist in patients for many years despite strong anti-Borrelia antibody responses. Antimicrobial treatment of persistent infection is challenging. Similar to humans, B. burgdorferi establishes long-term infection in various experimental animal models except in New Zealand White (NZW) rabbits, which clear the spirochete within 4-12 weeks. LD spirochetes have a highly evolved antigenic variation vls system, on the lp28-1 plasmid, where gene conversion results in surface expression of antigenically variable VlsE protein. VlsE is required for B. burgdorferi to establish persistent infection by continually evading otherwise potent antibody. Since the clearance of B. burgdorferi is mediated by humoral immunity in NZW rabbits, the previously published results that LD spirochetes lose lp28-1 during the rabbit infection could potentially explain the failure of B. burgdorferi to persist. However, the present study unequivocally disproves that prior finding by demonstrating that LD spirochetes retain the vls system. Yet, despite the vls system being fully functional, the spirochete fails to evade anti-Borrelia antibody of the NZW rabbit. In addition to being protective against homologous and heterologous challenge, the rabbit antibody significantly ameliorate LD-induced arthritis in persistently infected mice. Overall, the current data indicate that NZW rabbits develop a protective antibody repertoire, whose specificities once defined will identify potential candidates for a much-anticipated LD vaccine.
Ian Rose, Melissa Hardstone Yoshimizu, Denise L. Bonilla, Natalia Fedorova, Robert S. Lane, Kerry A. Padgett
by Ian Rose, Melissa Hardstone Yoshimizu, Denise L. Bonilla, Natalia Fedorova, Robert S. Lane, Kerry A. Padgett
The common human-biting tick, Ixodes pacificus, is the primary vector of the Lyme disease spirochete, Borrelia burgdorferi sensu stricto (ss) in western North America and has been found to harbor other closely-related spirochetes in the Borrelia burgdorferi sensu lato (sl) complex. Between 2008–2015, 11,066 adult and 3,815 nymphal I. pacificus and five adult and 144 nymphal Ixodes spinpalpis, a commonly collected wildlife tick, were collected from 42 California counties. Borrelia burgdorferi sl was detected in 1.2% and 3.8% I. pacificus adults and nymphs, respectively. Results from this study indicate genetic diversity and geographic structure of B. burgdorferi sl in California I. pacificus ticks, by sequence comparison of the16S rRNA gene, with B. burgdorferi ss, the agent of Lyme disease, found only in I. pacificus collected from the north and central coastal and Sierra Nevada foothill regions; B. burgdorferi ss was not detected in ticks tested from southern California. In contrast, Borrelia bissettiae, a member of the B. burgdorferi sl complex, was detected in both I. pacificus and I. spinipalpis, in the coastal region of both northern and southern California, but was absent from ticks in the Sierra Nevada foothills. In a similar pattern to B. bissettiae, Borrelia americana (a member of the B. burgdorferi sl complex) was detected in a single adult I. pacificus from the north coast and two I. spinipalpis nymphs from south-coastal California. This study highlights that the geographic area of Lyme disease acarological risk in California is the north-central and Sierra Nevada foothill regions of the state with little to no risk in the southern regions of the state.
Susannah B. Lerman, Vincent D’Amico
by Susannah B. Lerman, Vincent D’Amico
Forests have become increasingly fragmented throughout the US, with residential development serving as the primary driver of these changes. These altered landscapes have provided suitable conditions for a broad range of wildlife, including blacklegged ticks and their hosts. Lawns dominate residential landscapes, and thus their management has the potential to reduce the likelihood of contact with ticks in residential yards. We tested the hypothesis that lawn mowing frequency influences tick occurrence in 16 suburban yards in Springfield, MA. We conducted 144 tick drags in lawns of various lawn mowing frequencies (mowed every week, every 2-weeks and every 3-weeks) and did not collect any ticks of any species. Promoting frequent mowing (i.e., shorter lawns) and the removal of grass clippings could have minimal impacts on tick microhabitats, but is consequential for beneficial wildlife and other ecosystem services associated with urban biodiversity.
Pospisilova, T., Urbanova, V., Hes, O., Kopacek, P., Hajdusek, O., Sima, R.
Quantitative and microscopic tracking of Borrelia afzelii transmission from infected Ixodes ricinus nymphs has shown transmission cycle different from Borrelia burgdorferi and Ixodes scapularis. Borrelia afzelii are abundant in the guts of unfed I. ricinus nymphs and their numbers continuously decrease during feeding. Borrelia afzelii spirochetes are present in murine skin within 1 day of tick attachment. In contrast, spirochetes were not detectable in salivary glands at any stage of tick feeding. Further experiments demonstrated that tick saliva is not essential for B. afzelii infectivity, the most important requirement for successful host colonization being a change in expression of outer surface proteins that occurs in the tick gut during feeding. Spirochetes in vertebrate mode are then able to survive within the host even in the absence of tick saliva. Taken together, our data suggest that the tick gut is the decisive organ that determines the competence of I. ricinus to vector B. afzelii. We discuss possible transmission mechanisms of B. afzelii spirochetes that should be further tested in order to design effective preventive and therapeutic strategies against Lyme disease.
R. P. Smith et al.
International Liver Congress (ILC) 2020
27.08.2020 - 29.08.2020
World Sepsis Day
Det 8. videnskabelige nationale møde om infektiøs endokarditis
International Congress for Tropical Medicine and Malaria (ICTMM) 2020
20.09.2020 - 24.09.2020
Meeting of the European Society for Immunodeficiencies (ESID) 2020
14.10.2020 - 17.10.2020
COVID-19 retningslinje (2020)
National handlingsplan for antibiotika til mennesker (2017)
Retningslinjer til sundhedsprofessionelle vedr. håndtering af infektion med zikavirus (2019)
Infections in Patients Colonized with Extended-Spectrum Beta-Lactamase-Producing Enterobacterales – a Retrospective Cohort Study
30.07.2020Clinical Infectious Diseases Advance Access
Effectiveness of Cloth Masks for Protection Against Severe Acute Respiratory Syndrome Coronavirus 2
22.07.2020Emerging Infectious Diseases Journal
Coronavirus Disease among Persons with Sickle Cell Disease, United States, March 20–May 21, 2020
22.07.2020Emerging Infectious Diseases Journal
COVID-19: the worst may be yet to come
First step in a new era for treatment of patients with vitiligo
Hvad synes Professor Jens Lundgren om"Dolutegravir plus Two Different Prodrugs of Tenofovir to Treat HIV."?
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