The hard tick Ixodes ricinus serves as vector for life-threatening tick-borne diseases (TBDs) such as Lyme borreliosis, relapsing fever, and tick-borne encephalitis. Due to the ticks` ability to adjust to climate changes, their habitat is expanding quickly across Europe, and the incidences of TBD´s are increasing. Therefore, to better understand and control TBDs it is essential to expand the knowledge about the ticks´ microbiome, particularly the spatiotemporal and tissue-specific dynamics of I. ricinus bacterial community. This study was designed to investigate the differences in the detected bacterial communities according to the locations, where ticks had been collected, according to ticks´ tissue types and to seasonal impacts.

ATP1A3-related disorders comprise an expanding group of ultra-rare neurologic conditions, classically including rapid-onset dystonia-parkinsonism (RDP), alternating hemiplegia of childhood (AHC), and cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss (CAPOS) syndrome. However, accumulating reports suggest a broader and overlapping phenotypic spectrum. In this context, we established the ATP1A3 Study Group to comprehensively characterize the phenotypic and genotypic spectrum of ATP1A3-related disorders in a Brazilian cohort.

A 2-year-old, spayed female, mixed breed dog presented for evaluation of recurrent febrile episodes over 5 months, intermittently accompanied by the development of SC nodules. Histopathologic examination of the SC lesions was indicative of panniculitis. Bartonella vinsonii subsp. berkhoffii genotype III DNA was amplified and sequenced from an excised SC nodule. Indirect immunofluorescence antibody titer was 1:64, whereas Bartonella blood PCR was negative. Babesia odocoilei-like species DNA was amplified and sequenced from 2 blood samples obtained 77 days apart at the time of febrile episodes. Treatment with doxycycline, enrofloxacin, and azithromycin for 6 months resulted in a favorable clinical outcome. Fifteen months later, the dog remained healthy. This case indicates that relapsing fever and panniculitis are possible manifestations of B vinsonii subsp. berkhoffii genotype III infection in dogs. To the best of the authors' knowledge, infection with a B odocoilei-like species has not been reported previously in dogs from Greece.

Tick-borne relapsing fever (TBRF) spirochetes are maintained in nature through vector-associated transmission routes primarily in argasid ticks. However, the extent to which strain-level differences influence the maintenance of TBRF spirochetes remains unclear. We evaluated two Borrelia turicatae strains, Bt -SSK1 and Bt -FCB, in Ornithodoros turicata . Both strains were acquired by female ticks, and after mating we unexpectedly observed that they were hyperparasitized by uninfected and unfed male O. turicata. Bt - SSK1 was maintained in males while Bt- FCB was not. Transovarial transmission (TOT) of Bt -SSK1 and Bt -FCB was also evaluated and striking differences were observed between strains. Bt -SSK1 was vertically maintained in F1 progeny but we failed to detect TOT of Bt -FCB. TOT of Bt -SSK1 occurred inefficiently in early ovipositions but increasing in later or delayed reproductive events, indicating a timing-dependent barrier. Using a gfp -expressing Bt -FCB strain, we show that failure of vertical transmission is associated with a lack of persistent oocyte colonization despite dissemination to ovarian tissues. These findings demonstrate strain-dependent differences in oocyte colonization and represent a critical bottleneck governing vertical transmission and persistence of relapsing fever spirochetes in tick populations.

Intravenous calcium is the standard treatment for milk fever, although adjunctive therapies such as oral calcium or parenteral phosphorus are often used, with unclear additional benefits. This study evaluated whether adjunctive calcium or phosphorus therapies improve clinical and biochemical recovery following intravenous calcium treatment. This prospective study included 41 postpartum cows with milk fever randomly assigned to five treatment groups. All received intravenous calcium alone or combined with oral calcium pidolate or chloride boluses, liquid calcium or parenteral toldimfos. Plasma calcium, phosphorus, magnesium, parathyroid hormone, and calcitriol were measured before treatment and repeated up to 96 h post-infusion. Clinical outcomes, including time to standing, relapse, and alert downer status, were recorded. All cows stood following treatment. Nine relapsed and two of them were euthanized because of persistent recumbency. Adjunctive treatments did not improve clinical or biochemical recovery compared with intravenous calcium alone, which restored normocalcemia for approximately 8 h. Pretreatment calcitriol level was significantly lower in cows that relapsed than in those recovering within 96 h. Pre-treatment blood calcium was lower in cows with a single relapse but higher in alert downers. At 24 h, plasma calcium and phosphorus were lower in cows with a single relapse than in non-relapsing cows, whereas only plasma phosphorus was lower in cows with multiple relapses. These findings suggest that milk fever relapse may be linked to impaired calcium-vitamin D metabolism rather than phosphorus deficiency. Further research is warranted to confirm these results and optimize strategies for preventing relapses in dairy cows.

Accurate diagnosis of bacterial meningitis is critical, particularly in young febrile infants. Although commercially available multiplex PCR assays enable rapid pathogen detection, these typically do not include Salmonella spp. or other Enterobacteriaceae, which may result in missed diagnoses and/or inappropriate treatment duration. We report the case of a 2-month-old female infant with Salmonella enteritidis meningitis and concurrent bacteremia. The patient initially presented with fever, lethargy, and a bulging anterior fontanelle. Cerebrospinal fluid (CSF) analysis was highly suggestive of bacterial meningitis. However, both CSF culture and the FilmArray ME Panel were negative, likely due to prior empirical antibiotic therapy at another hospital. The causative organism was isolated on blood cultures. The infant was treated with intravenous ceftriaxone for 24 days and discharged in excellent clinical condition. Twelve days later, she was readmitted with a relapse of meningitis and bacteremia caused by the same pathogen. She received combination therapy with cefotaxime and cotrimoxazole for 37 days, followed by cefotaxime monotherapy for another 26 days. Immunological evaluation, including assessment of immunoglobulin levels, lymphocyte subsets, and interferon-γ receptor and Interleukin-12 receptor expression, was normal. The patient had a favorable outcome with complete clinical and laboratory recovery and a normal neurodevelopmental outcome at follow-up. Salmonella meningitis is a rare but life-threatening condition in infants, which may be overlooked when relying on molecular diagnostic panels that do not include this pathogen. Negative CSF PCR results should be interpreted with caution in the presence of typical cytological and biochemical findings of bacterial meningitis. Prolonged antimicrobial therapy of at least 4-6 weeks is essential to prevent relapse and ensure optimal microbiologic and clinical outcomes.

An early adolescent boy, born to a consanguineously married couple, with mild baseline developmental delay, presented with fever-triggered acute encephalopathy manifesting as ataxia, tremors and seizures. Neuroimaging revealed multifocal, symmetric involvement of the insular cortex, basal ganglia, temporo-occipital regions and cerebellum with diffusion restriction. Extensive infectious, autoimmune and metabolic evaluation during the first episode was inconclusive, and he was treated as immune-mediated encephalitis with partial recovery. Three months later, febrile illness precipitated a severe relapse with neurological regression, movement disorder and progressive cerebellar atrophy on follow-up imaging. Given the relapsing fever-triggered course, baseline developmental delay, incomplete recovery, negative autoimmune workup and progressive neuroimaging changes without new inflammatory lesions, a genetic aetiology was suspected. Genetic testing identified a homozygous variant in the NUP214 gene, supporting a diagnosis of acute infection-induced encephalopathy type 9. This case highlights the importance of considering genetic susceptibility in children with recurrent infection-triggered encephalopathy and atypical recovery.

Bacterial zoonoses constitute a significant proportion of emerging infectious diseases. Yet, the diversity and transmission cycles of many zoonotic bacteria remain poorly characterized, particularly in tropical, biodiverse regions where host and vector diversity are high, and the burden of zoonotic disease in human populations is substantial. In this study, we investigated the presence of five pathogenic bacterial genera-Rickettsia, Borrelia, Orientia, Leptospira, and Coxiella-in rodents from southern India. We detected low circulation of Rickettsia (7.26%), Borrelia (6.45%), and Leptospira (0.8%), with limited coinfections, whereas Orientia and Coxiella were not detected in the rodents sampled. Notably, we observed contrasting patterns of tissue association, with rickettsiae detected exclusively in pooled organ tissues and borreliae detected only in blood, suggesting the influence of pathogen biology in detection probabilities. Our phylogenetic analyses further confirmed that the detected Rickettsia and Borrelia belonged to the spotted fever group rickettsiae and relapsing fever group borreliae, respectively, in both synanthropic and forest-associated rats, highlighting a potential transmission risk to people and livestock in the region. By revealing the circulation of zoonotic bacteria in new host species, this study underscores the need for systematic surveillance of wildlife to better characterize bacterial diversity and its public health implications.

Adult-onset Still's disease (AOSD) is a rare systemic autoinflammatory condition that presents with symptoms such as episodic fevers, a transient rash, inflammatory arthritis, and significant systemic inflammation. Diseases that have a relapsing-remitting clinical course can be challenging to diagnose and treat. We present a case of an 18 year old female with multiple flares over several years requiring stepwise escalation from conventional disease-modifying antirheumatic drugs (DMARDs) to targeted biologic therapy, highlighting the challenges of achieving durable remission. Our patient presented with recurrent episodes of high-grade fever (up to 40°C), evanescent salmon-pink rash, bilateral symmetrical inflammatory polyarthritis involving the wrists, metacarpophalangeal (MCP), proximal interphalangeal (PIP) joints, and knees with mild splenomegaly. After ruling out infectious, malignant, and other autoimmune diseases via biochemical, serological, autoimmune testing and biopsy, she was diagnosed with AOSD on the basis of the Yamaguchi criteria. Despite receiving treatment with corticosteroids and conventional disease-modifying antirheumatic drugs (DMARDs), including methotrexate, she suffered from multiple relapses, indicating a polycyclic disease pattern. The introduction of biologic therapy with tocilizumab provided temporary remission. However, her flares returned during the tapering of steroids, necessitating an increase in the dosage and the use of pulse corticosteroid therapy during the current admission. This case report illustrates the relapsing-remitting nature of AOSD. Escalation to IL-6 receptor inhibition (tocilizumab) is required in DMARDs refractory relapsing AOSD, with dose optimization to achieve sustained remission of disease activity of our patient.