Lyme disease can result in severe neuropsychiatric symptoms that may be resistant to treatment. The pathogenesis of neuropsychiatric Lyme disease is associated with autoimmune induced neuroinflammation. This case report describes an immunocompetent male with serologically positive neuropsychiatric Lyme disease who did not tolerate antimicrobial or psychotropic medications and whose symptoms remitted when he began psilocybin in microdosed (sub-hallucinogenic) amounts. A literature review of its therapeutic benefits reveals that psilocybin is both serotonergic and anti-inflammatory and therefore may offer significant therapeutic benefits to patients with mental illness secondary to autoimmune inflammation. The role of microdosed psilocybin in the treatment of neuropsychiatric Lyme disease and autoimmune encephalopathies warrants further study.

Long-term cognitive problems after neuroborreliosis treatment remain a subject of debate. We have previously shown that cognitive problems are not present in the acute phase of neuroborreliosis, although fatigue is common. The aim of this study was to re-assess the same patient cohort and evaluate long-term outcomes.
In this follow-up, we re-assessed 58 patients with well-characterized neuroborreliosis 12 months after completing treatment. The same protocol with eight subtests measuring attention and processing speed and the Fatigue Severity Scale (FSS) were used to compare the results from the acute phase to 12 months post treatment.
We found no changes in attention or processing speed but a reduction in the level of fatigue (median score on FSS: 4.9 vs. 3.9, p < .001) from the acute phase to 12 months post treatment.
The patient group did not develop problems with attention or processing speed post treatment, while the level of fatigue decreased.

The density of Borrelia burgdorferi-infected Ixodes ricinus nymphs (DIN) was investigated during 2013-2017 across a Lyme disease-endemic landscape in southern England. The density of nymphs (DON), nymph infection prevalence (NIP), and DIN varied across five different natural habitats, with the highest DIN in woodland edge and high biodiversity woodlands. DIN was significantly lower in scrub grassland compared to the woodland edge, with low DON and no evidence of infection in ticks in non-scrub grassland. Over the 5 years, DON, NIP and DIN were comparable within habitats, except in 2014, with NIP varying three-fold and DIN significantly lower compared to 2015-2017. Borrelia garinii was most common, with bird-associated Borrelia (B. garinii/valaisiana) accounting for ~70% of all typed sequences. Borrelia burgdorferi sensu stricto was more common than B. afzelii. Borrelia afzelii was more common in scrub grassland than woodland and absent in some years. The possible impact of scrub on grazed grassland, management of ecotonal woodland margins with public access, and the possible role of birds/gamebirds impacting NIP are discussed. Mean NIP was 7.6%, highlighting the potential risk posed by B. burgdorferi in this endemic area. There is a need for continued research to understand its complex ecology and identify strategies for minimizing risk to public health, through habitat/game management and public awareness.

BACKGROUND: The neurological effects of Lyme borreliosis in children are varied and their clinical progression is not widely reported in the French literature. We carried out a retrospective study to describe the clinical characteristics of Lyme neuroborreliosis in children in southwest France and their clinical progression at 6 months.
METHODS: This study was carried out at Toulouse University Hospital during the period 2006-2017 using patient records. Case definition was based on the combined French clinical and laboratory diagnostic criteria.
RESULTS: In total, 26 children were included. The median age was 8 years (4-14 years). The different neurological symptoms reported were: meningoradiculitis (62%), which was usually associated with facial palsy (54%); isolated facial palsy (15%); isolated meningitis (8%); polyradiculoneuritis (4%); benign intracranial hypertension (4%) and myelomeningoradiculitis (4%). The most common functional symptoms were headaches (54%), the perception of asthenia (42%), neck pain (27%), and a loss of appetite (19%). Patients with laboratory meningitis (84%) often had no signs of meningism or headaches (38%).
CONCLUSIONS: The majority of the cases involved meningoradiculitis but other, less common, neurological conditions have been described. The clinical signs suggestive of meningitis are not very marked and might delay the diagnosis.

The complex etiology of neurodegenerative disease has prompted studies on multiple mechanisms including genetic predisposition, brain biochemistry, immunological responses, and microbial insult. In particular, Lyme disease is often associated with neurocognitive impairment with variable manifestations between patients. We sought to develop methods to reliably detect Borrelia burgdorferi, the spirochete bacteria responsible for Lyme disease, in autopsy specimens of patients with a history of neurocognitive disease. In this report, we describe the use of multiple molecular detection techniques for this pathogen and its application to a case study of a Lyme disease patient. The patient had a history of Lyme disease, was treated with antibiotics, and years later developed chronic symptoms including dementia. The patient\'s pathology and clinical case description was consistent with Lewy body dementia. B. burgdorferi was identified by PCR in several CNS tissues and by immunofluorescent staining in the spinal cord. These studies offer proof of the principle that persistent infection with the Lyme disease spirochete may have lingering consequences on the CNS.

Understanding the variation in Borrelia burgdorferi s.l. infection rates in Ixodes ricinus ticks is important for assessing the potential for Lyme borreliosis transmission. This study aimed to investigate infection rates of B. burgdorferi s.l. bacteria in I. ricinus across 24 field sites in England and Wales, focussing on protected recreational areas in National Parks (NPs) and Areas of Outstanding Natural Beauty (AONBs), to provide comparable data across multiple years to assess spatio-temporal changes in B. burgdorferi s.l. infection. Working with park rangers, questing ticks were collected each spring from 2014 to 2019. A subset of ticks, 4104 nymphs, were analysed using a pan-Borrelia qPCR assay, as well as a Borrelia miyamotoi-specific qPCR, and sequenced to determine Borrelia burgdorferi s.l. genospecies. Site-specific B. burgdorferi s.l. infection rates in I. ricinus nymphs varied from 0% to 24%, with overall infection rates ranging from 2.5% to 5.1% across the years. Genospecies composition of sequenced samples was 62.5% B. garinii, 20.3% B. valaisiana and 17.2% B. afzelii. Borrelia miyamotoi was detected in 0.2% of ticks. This study increases our knowledge on B. burgdorferi s.l.. infection in areas used by the public for outdoor activity across England and Wales, highlighting the spatial and temporal variability which can impact the changing risk to humans from infected tick bites.

BACKGROUND: Serological screening tests for Lyme borreliosis have poor specificity, with potential for misdiagnosis and unnecessary antimicrobial treatment.
OBJECTIVE: To evaluate the impact of Lyme borreliosis seroprevalence and serologic test characteristics on the probability of obtaining a false-positive result and impact on antimicrobial use.
METHODS: Cross-sectional serological survey and modelling.
METHODS: Sera from 303 horses in southern Belgium were analysed by enzyme-linked immunosorbent assay (ELISA). Apparent seroprevalence was derived from serological data and a Bayesian estimate of true seroprevalence was computed. These were a starting point to model the impact of test and population characteristics on the probability of obtaining false-positive results and consequently unnecessary treatments and complications.
RESULTS: Apparent and true seroprevalence were 22% (95% CI 18%-27%) and 11% (credible interval with 95% probability 0.6%-21%) respectively. We estimate that two-thirds of positive samples are false positive in southern Belgium, with one in five of tested horses potentially misdiagnosed as infected. Around 5% of antimicrobial use in equine veterinary practice in Belgium may be attributable to treatment of a false-positive result.
UNASSIGNED: There was uncertainty regarding the ELISA\'s sensitivity and specificity.
CONCLUSIONS: This study highlights the importance of appreciating the poor diagnostic value of ELISA screening for Lyme borreliosis as demonstrated by this case study of seroprevalence in southern Belgium where we demonstrate that a nontrivial number of horses is estimated to receive unwarranted treatment due to poor appreciation of screening test characteristics by practitioners, contributing substantially to unnecessary use of antimicrobials.

BACKGROUND: Vector-borne pathogens are emerging concerns in multiple regions of Canada. Determining regional prevalence of canine vector-borne pathogens and documenting change will improve clinician awareness, enable targeted prevention, enhance diagnosis and ideally reduce the risk of disease. Study objectives were to: (i) estimate the prevalence of positive canine vector-borne test results from samples submitted in Canada; (ii) assess change in prevalence over time, from baseline (2008) to 2015; and (iii) estimate the prevalence of pathogen co-infections.
METHODS: This repeat cross-sectional study evaluated 753,468 test results for D. immitis antigen and B. burgdorferi, Ehrlichia canis/ewingii/muris serology, and 753,208 test results for Anaplasma phagocytophilum/platys serology using the SNAP® 4Dx®Test and SNAP 4Dx® Plus Test.
RESULTS: Based on all submitted samples from Canada (2008-2015), the period seroprevalence of B. burgdorferi, Ehrlichia spp., Anaplasma spp. and D. immitis antigen were 2.0%, 0.5%, 0.4% and 0.2%, respectively. Over the 7 years (2008 compared to 2015) we observed a significant increase in seroprevalence for B. burgdorferi (144.4%) and Ehrlichia spp. (150%). Co-infections (positive for two or more pathogens on a single 4 pathogen test kit) were estimated at 5.4% (1162/21,612) of total positive tests.
CONCLUSIONS: The temporal rise and geographical differences in prevalence detected for these pathogens (notably B. burgdorferi) are consistent with anecdotal information on canine illness related to tick-borne pathogen exposure in multiple regions of Canada, particularly canine Lyme disease.

Previous studies, mostly case reports and uncontrolled studies, provide a low level of evidence for the hypothesized link between Lyme disease and amyotrophic lateral sclerosis (ALS). In order to make evidence-based recommendations regarding testing for Borrelia burgdorferi antibodies in the diagnostic work-up for ALS, the objective of this study was to explore the evidence for an association between these antibodies and ALS in a case-control design including age-, gender- and residency-matched controls.
A total of 491 patients with ALS were matched to 982 controls. IgG titers against B. burgdorferi were determined by an enzyme-linked immunosorbent assay and, in the case of positivity or borderline results, a western blot was performed. Conditional logistic regression and Fisher\'s exact tests were used to compare the antibody titers or positivity between patients and controls.
No difference in seroprevalence of Borrelia was found between patients (4.1%) and controls (5.9%). Clinical characteristics and survival were similar between seropositive and seronegative patients. Moreover, patients with a spinal onset were not more frequently seropositive compared with patients with a bulbar onset (P = 0.47), and neither were patients with a short diagnostic delay of <6 months compared with controls (P = 0.69). None of the 20 patients with a diagnostic delay of <3 months tested positive for IgM antibodies, suggestive of a recent infection.
This large case-control study provides evidence for a lack of association between B. burgdorferi antibodies and ALS, and therefore does not support the inclusion of routine testing for these antibodies in the diagnostic work-up in patients with classical ALS.