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Case report…

Infection and Immunity, Ahead of Print. …

by Ariane Dumas, Catherine Bouchard, Antonia Dibernardo, Pierre Drapeau, L. Robbin Lindsay, Nicholas H. Ogden, Patrick A. Leighton

Ixodes scapularis ticks are expanding their range in parts of northeastern North America, bringing with them pathogens of public health concern. While rodents like the white-footed mouse, Peromyscus leucopus, are considered the primary reservoir of many emerging tick-borne pathogens, the contribution of birds, as alternative hosts and reservoirs, to local transmission cycles has not yet been firmly established. From 2016 to 2018, we collected host-seeking ticks and examined rodent and bird hosts for ticks at 48 sites in a park where blacklegged ticks are established in Quebec, Canada, in order to characterize the distribution of pathogens in ticks and mammalian and avian hosts. We found nearly one third of captured birds (n = 849) and 70% of small mammals (n = 694) were infested with I. scapularis. Five bird and three mammal species transmitted Borrelia burgdorferi to feeding larvae (n larvae tested = 2257) and we estimated that about one fifth of the B. burgdorferi-infected questing nymphs in the park acquired their infection from birds, the remaining being attributable to mice. Ground-foraging bird species were more parasitized than other birds, and species that inhabited open habitat were more frequently infested and were more likely to transmit B. burgdorferi to larval ticks feeding upon them. Female birds were more likely to transmit infection than males, without age differentiation, whereas in mice, adult males were more likely to transmit infection than juveniles and females. We also detected Borrelia miyamotoi in larvae collected from birds, and Anaplasma phagocytophilum from a larva collected from a white-footed mouse. This study highlights the importance of characterising the reservoir potential of alternative reservoir hosts and to quantify their contribution to transmission dynamics in different species assemblages. This information is key to identifying the most effective host-targeted risk mitigation actions.

Infection and Immunity, Ahead of Print. …

Infection and Immunity, <a href='https://journals.asm.org/toc/iai/0/ja'>Volume 0, Issue ja</a>, -Not available-. …

Journal Name: The American Journal of Tropical Medicine and HygieneVolume: 106Issue: 1Pages: 45-46

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AbstractBackgroundQuantiFERON enzyme-linked immunosorbent assay (ELISA; Qiagen) with Borrelia burgdorferi peptide antigens was previously shown to reliably detect interferon-γ (IFN-γ) in blood samples from adult patients with early Lyme disease and the response disappeared rapidly after treatment. We evaluated the response before and after appropriate antibiotic therapy in adolescent and adult subjects with more diverse stages of the illness.MethodsBlood was obtained from patients with clinician-identified Lyme disease with constitutional complaints, erythema migrans, nerve palsy, cardiac abnormality, or arthritis before (n = 68) and 6 weeks (n = 46) and 6 months (n = 45) after therapy. The sera were tested for Lyme disease by standard 2-tiered testing (STTT) and anti–C6 antibodies by ELISA and the levels of IFN-γ in the blood samples were detected by QuantiFERON ELISA.ResultsA positive STTT result supported the clinical diagnosis of 37 (54%) subjects and anti-C6 antibodies were detected in 45 (66%) subjects, including 36 (97%) STTT-positive subjects, and the responses often persisted or expanded after antibiotic therapy. IFN-γ was detected in 49 (72%) subjects prior to treatment and the response most often significantly decreased 6 weeks (P = .007) or 6 months (P = .001) after treatment.ConclusionsThe QuantiFERON ELISA reliably detected IFN-γ in blood samples from adult and adolescent patients with varying stages of Lyme disease and the response disappeared rapidly after treatment. Additional studies to more critically evaluate clinical utility as a laboratory test for diagnosis and confirmation of effective therapy are warranted.

Abstract

Background

Erythema migrans (EM) is the most common manifestation of Lyme borreliosis. Here, we examined EM patients in Norwegian general practice to find the proportion exposed to tick-transmitted microorganisms other than Borrelia, and the impact of co-infection on the clinical manifestations and disease duration.

Methods

Skin biopsies from 139/188 EM patients were analyzed using PCR for Neoehrlichia mikurensis, Rickettsia spp., Anaplasma phagocytophilum and Babesia spp. Follow-up sera from 135/188 patients were analyzed for spotted fever group (SFG) Rickettsia, A. phagocytophilum and Babesia microti antibodies, and tested with PCR if positive. Day 0 sera from patients with fever (8/188) or EM duration of ≥ 21 days (69/188) were analyzed, using PCR, for A. phagocytophilum, Rickettsia spp., Babesia spp. and N. mikurensis. Day 14 sera were tested for TBEV IgG.

Results

We detected no microorganisms in the skin biopsies nor in the sera of patients with fever or prolonged EM duration. Serological signs of exposure against SFG Rickettsia and A. phagocytophilum were detected in 11/135 and 8/135, respectively. Three patients exhibited both SFG Rickettsia and A. phagocytophilum antibodies, albeit negative PCR. No antibodies were detected against B. microti. 2/187 had TBEV antibodies without prior immunization. There was no significant increase in clinical symptoms or disease duration in patients with possible co-infection.

Conclusions

Co-infection with N. mikurensis, A. phagocytophilum, SFG Rickettsia, Babesia spp. and TBEV is uncommon in Norwegian EM patients. Despite detecting antibodies against SFG Rickettsia and A. phagocytophilum in some patients, no clinical implications could be demonstrated.

Abstract

Background

Erythema migrans (EM) is the most common manifestation of Lyme borreliosis. Here, we examined EM patients in Norwegian general practice to find the proportion exposed to tick-transmitted microorganisms other than Borrelia, and the impact of co-infection on the clinical manifestations and disease duration.

Methods

Skin biopsies from 139/188 EM patients were analyzed using PCR for Neoehrlichia mikurensis, Rickettsia spp., Anaplasma phagocytophilum and Babesia spp. Follow-up sera from 135/188 patients were analyzed for spotted fever group (SFG) Rickettsia, A. phagocytophilum and Babesia microti antibodies, and tested with PCR if positive. Day 0 sera from patients with fever (8/188) or EM duration of ≥ 21 days (69/188) were analyzed, using PCR, for A. phagocytophilum, Rickettsia spp., Babesia spp. and N. mikurensis. Day 14 sera were tested for TBEV IgG.

Results

We detected no microorganisms in the skin biopsies nor in the sera of patients with fever or prolonged EM duration. Serological signs of exposure against SFG Rickettsia and A. phagocytophilum were detected in 11/135 and 8/135, respectively. Three patients exhibited both SFG Rickettsia and A. phagocytophilum antibodies, albeit negative PCR. No antibodies were detected against B. microti. 2/187 had TBEV antibodies without prior immunization. There was no significant increase in clinical symptoms or disease duration in patients with possible co-infection.

Conclusions

Co-infection with N. mikurensis, A. phagocytophilum, SFG Rickettsia, Babesia spp. and TBEV is uncommon in Norwegian EM patients. Despite detecting antibodies against SFG Rickettsia and A. phagocytophilum in some patients, no clinical implications could be demonstrated.

AbstractBackgroundLyme neuroborreliosis peripheral facial palsy (LNB PFP) and idiopathic PFP, Bell’s palsy (BP), are the most common causes of facial palsy in borrelia-endemic areas and are clinically similar. Early treatment with corticosteroids has been shown to be effective in Bell’s palsy, and antibiotics improve the outcome in LNB. However, there is a lack of knowledge on how the addition of corticosteroids to standard antibiotic treatment affects the outcome in LNB PFP.MethodsThis prospective, open trial with historical controls was conducted at 2 large hospitals in western Sweden between 2011 and 2018. Adults who presented with LNB PFP were included in the study group and were treated with oral doxycycline 200 mg twice daily for 10 days and prednisolone 60 mg once daily for 5 days, then tapered over 5 days. The historical controls were adult patients with LNB PFP included in previous studies and treated with oral doxycycline. Both groups underwent a follow-up lumbar puncture and were followed until complete recovery or for 12 months.ResultsFifty-seven patients were included, 27 in the study group and 30 in the control group. Two patients (7%) in the study group and 6 patients (20%) in the control group suffered from sequelae at the end follow-up. There was no statistically significant difference between the groups, either in the proportion of patients with sequelae or in the decline in cerebrospinal fluid mononuclear cell count.ConclusionsAdjunctive corticosteroids neither improve nor impair the outcome for patients with LNB PFP treated with doxycycline.

by Richard Porwancher, Lisa Landsberg

Multiple different recombinant and peptide antigens are now available for serodiagnosis of Lyme disease (LD), but optimizing test utilization remains challenging. Since 1995 the Centers for Disease Control and Prevention (CDC) has recommended a 2-tiered serologic approach consisting of a first-tier whole-cell enzyme immunoassay (EIA) for polyvalent antibodies to Borrelia burgdorferi followed by confirmation of positive or equivocal results by IgG and IgM immunoblots [standard 2-tiered (STT) approach]. Newer modified 2-tiered (MTT) approaches employ a second-tier EIA to detect antibodies to B. burgdorferi rather than immunoblotting. We applied modern bioinformatic techniques to a large public database of recombinant and peptide antigen-based immunoassays to improve testing strategy. A retrospective CDC collection of 280 LD samples and 559 controls had been tested using the STT approach as well as kinetic-EIAs for VlsE1-IgG, C6-IgG, VlsE1-IgM, and pepC10-IgM antibodies. When used individually, the cutoff for each kinetic-EIA was set to generate 99% specificity. Utilizing logistic-likelihood regression analysis and receiver operating characteristic (ROC) techniques we determined that VlsE1-IgG, C6-IgG, and pepC10-IgM antibodies each contributed significant diagnostic information; a single-tier diagnostic score (DS) was generated for each sample using a weighted linear combination of antibody levels to these 3 antigens. DS performance was then compared to the STT and to MTT models employing different combinations of kinetic-EIAs. After setting the DS cutoff to match STT specificity (99%), the DS was 22.5% more sensitive than the STT for early-acute-phase disease (95% CI: 11.8% to 32.2%), 16.0% more sensitive for early-convalescent-phase disease (95% CI: 7.2% to 24.7%), and equivalent for detection of disseminated infection. The DS was also significantly more sensitive for early-acute-phase LD than MTT models whose specificity met or exceeded 99%. Prospective validation of this single-tier diagnostic score for Lyme disease will require larger studies using a broader range of potential cross-reacting conditions.

A previously healthy 42-year-old male from the upper Midwestern United States presented with a 1-day history of fever, fatigue, headache, myalgias, and arthralgias. He reported removing a “wood tick” the day of admission. His temperature was 38.4°C. No swollen joints, rash, or neurological abnormalities were noted on physical examination.

Infection and Immunity, <a href="https://journals.asm.org/toc/iai/0/ja">Volume 0, Issue ja</a>, -Not available-.