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Background: Crimean Congo hemorrhagic fever (CCHF) is endemic in Southern Mauritania where recurrent outbreaks have been constantly observed since the 1980's. The present study is the first to assess CCHFV antibodies and RNA in humans., Methods: A retrospective study was conducted using 263 humans and 1380 domestic animals serum samples, and 282 tick specimens of Hyalomma genus collected from 54 settings in 12 provinces across Mauritania. Antibodies targeting CCHF viral nucleoprotein were detected in animal and human sera using double-antigen ELISA. CCHFV specific RNA was detected in human and animal sera as well as tick supernatants using a CCHFV real time RT-PCR kit. Individual characteristics of sampled hosts were collected at the same time and data were geo-referenced. Satellite data of several environmental and climatic factors, were downloaded from publicly available datasets, and combined with data on livestock mobility, animal and human density, road accessibility and individual characteristics to identify possible risk factors for CCHFV spatial distribution. To this end, multivariate logistic models were developed for each host category (human, small and large ruminants)., Results: The overall CCHFV antibody prevalence was 11.8% [95% CI: 8.4-16.3] in humans (17.9% in 2020 and 5.4% in 2021; p = 0.0017) and 33.1% (95% CI: 30.1-36.3) in livestock. CCHFV-specific antibodies were detected in 91 (18.1%) out of 502 sheep, 43 (9.0%) out of 477 goats, 144 (90.5%) out of 161 dromedaries and 179 (74.6%) out of 240 cattle. CCHFV RNA was detected in only 2 (0.7%) sera out of 263 animals herders samples from Hodh El Gharbi province and in 32 (11.3%) out of 282 Hyalomma ticks. In humans as well as in animals, seropositivity was not associated with sex or age groups. The multivariate analysis determined the role of different environmental, climatic and anthropic factors in the spatial distribution of the disease with animal mobility and age being identified as risk factors., Conclusion: Results of the present study demonstrate the potential risk of CCHF for human population in Mauritania primarily those living in rural areas in close vicinity with animals. Future studies should prioritize an integrative human and veterinary approach for better understanding and managing Crimean-Congo hemorrhagic fever., (© 2023. The Author(s).)

Background: Increasing numbers of tick-borne pathogens are being discovered, including those that infect humans. However, reports on co-infections caused by two or more tick-borne pathogens are scarce., Case Presentation: A 38-year-old male farmer was bitten by a hard tick, presented with fever (37.7 °C), severe headache and ejection vomiting. Lumbar puncture was performed in the lateral decubitus. The cerebrospinal fluid (CSF) was clear, and analysis showed severe increased pressure (320 mm H 2 O), mild leukocytosis (126.0 × 10 6 /L, mononuclear cells accounting for 73%) and elevated total protein concentration (0.92 g/L). Bacterial cultures of CSF and blood were negative. The diagnosis of Rickettsia raoultii and Tacheng tick virus 1 (TcTV-1) co-infection was confirmed by amplifying four rickettsial genetic markers and the partial small (S) RNA segment of TcTV-1 from the patient's blood. The patient gradually recovered after treatment with levofloxacin and ribavirin., Conclusions: This is the first reported co-infection case with fever and meningitis caused by R. raoultii and TcTV-1. It is vital to screen for multiple pathogens in tick-bitten patients, especially in those with severe complex symptoms., (© 2021. The Author(s).)

Background: Primary care and frontline healthcare providers are often the first point of contact for patients experiencing tick-borne disease (TBD) but face challenges when recognizing and diagnosing these diseases. The specific aim of this study was to gain a qualitative understanding of frontline and primary care providers' knowledge and practices for identifying TBDs in patients., Methods: From fall 2018 to spring 2019, three focus groups were conducted with primary care providers practicing in a small-town community endemic to Lyme disease (LD) and with emerging incidence of additional TBDs. A follow up online survey was distributed to urgent and emergency care providers in the small-town community and an academic medical center within the referral network of the local clinical community in spring and summer 2019. Qualitative analysis of focus group data was performed following a grounded theory approach and survey responses were analyzed through the calculation of descriptive statistics., Results: Fourteen clinicians from three primary care practices participated in focus groups, and 24 urgent and emergency care clinicians completed the survey questionnaire. Four overarching themes emerged from focus group data which were corroborated by survey data. Themes highlighted a moderate level of awareness on diagnosis and treatment of LD among participants and limited knowledge of diagnosis and treatment for two other regionally relevant TBDs, anaplasmosis and babesiosis. Providers described challenges and frustrations in counseling patients with strong preconceptions of LD diagnosis and treatment in the context of chronic infection. Providers desired additional point-of-care resources to facilitate patient education and correct misinformation on the diagnosis and treatment of TBDs., Conclusions: Through this small study, it appears that clinicians in the small-town and academic medical center settings are experiencing uncertainties related to TBD recognition, diagnosis, and patient communication. These findings can inform the development of point-of-care resources to aid in patient-provider communication regarding TBDs and inform the development of continuing medical education programs for frontline and primary care providers., (© 2021. The Author(s).)

Background: Kyasanur forest disease (KFD), known as monkey fever, was for the first time reported in 1957 from the Shivamogga district of Karnataka. But since 2011, it has been spreading to the neighbouring state of Kerala, Goa, Maharashtra, and Tamil Nadu. The disease is transmitted to humans, monkeys and by the infected bite of ticks Haemaphysalis spinigera. It is known that deforestation and ecological changes are the main reasons for KFD emergence, but the bio-climatic understanding and emerging pathways remain unknown.Methods: The present study aims to understand the bio-climatic determinants of distribution of tick vector of KFD in southern India using the Maximum Entropy (MaxEnt) model. The analysis was done using 34 locations of Haemaphysalis spinigera occurrence and nineteen bio-climatic variables from WorldClim. Climatic variables contribution was assessed using the Jackknife test and mean AUC 0.859, indicating the model performs with very high accuracy.Results: Most influential variables affecting the spatial distribution of Haemaphysalis spinigera were the average temperature of the warmest quarter (bio10, contributed 32.5%), average diurnal temperature range (bio2, contributed 21%), precipitation of wettest period (bio13, contributed 17.6%), and annual precipitation (bio12, contributed 11.1%). The highest probability of Haemaphysalis spinigera presence was found when the mean warmest quarter temperature ranged between 25.4 and 30 °C. The risk of availability of the tick increased noticeably when the mean diurnal temperature ranged between 8 and 10 °C. The tick also preferred habitat having an annual mean temperature (bio1) between 23 and 26.2 °C, mean temperature of the driest quarter (bio9) between 20 and 28 °C, and mean temperature of the wettest quarter (bio8) between 22.5 and 25 °C.Conclusions: The results have established the relationship between bioclimatic variables and KFD tick distribution and mapped the potential areas for KFD in adjacent areas wherein surveillance for the disease is warranted for early preparedness before the occurrence of outbreaks etc. The modelling approach helps link bio-climatic variables with the present and predicted distribution of Haemaphysalis spinigera tick. [ABSTRACT FROM AUTHOR]

Background: In areas where Lyme disease is endemic, bites from ticks are common, but no vaccine is currently available against Lyme disease for humans. Therefore, the feasibility of using antibiotic prophylaxis to prevent Lyme disease after a tick bite is worth further exploration. Previous meta-analyses lack sufficient power to demonstrate the efficacy of about antibiotic prophylaxis for the prevention of Lyme disease following a tick bite. In this study, we explored more precise evidence and attempted to identify and update optimum treatment strategies.Methods: We searched PubMed, Embase, and the Cochrane Library for studies until March 23, 2021. We included studies if the enrolled patients were randomly allocated to a treatment or control group within 72 h following a tick bite and had no clinical evidence of Lyme disease at enrolment. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were followed for data abstraction. Two authors (GZZ and XX) independently reviewed the abstracts and identified articles for detailed assessment. We used a random-effects model to calculate the pooled results and reported the 95% confidence interval (CI). Study quality was assessed using a modified Jadad scale, and publication bias was assessed using Egger's test. We calculated the risk ratio (RR) for the rates of unfavorable events in patients who received intervention versus the control group. This study is registered with PROSPERO, number CRD42021245002.Results: Six studies (3,766 individuals) were included. The pooled rate of unfavorable events in persons receiving treatment and the control group were 0.4% (95%CI: 0.1-1.1%) and 2.2% (95%CI: 1.6-3.0%), respectively. The pooled RR was 0.38 (95%CI: 0.22-0.66). Subgroup analysis revealed that the pooled RR was 0.29 (95%CI: 0.14-0.60) in the single-use 200-mg doxycycline group; 0.28 (95%CI: 0.05-1.67) in a 10-day course group (Amoxicillin, Penicillin or tetracycline); and 0.73 (95%CI: 0.25-2.08) in a topical antibiotic treatment group (Azithromycin).Conclusions: The available evidence supports the use of antibiotics for the prevention of Lyme disease, and reveals advantages of using single-dose; however, further confirmation is needed. [ABSTRACT FROM AUTHOR]

Background: Ehrlichiosis is a potentially fatal tick-borne disease that can progress to involve the central nervous system (CNS) (i.e., neuro-ehrlichiosis), particularly in cases where diagnosis and treatment are delayed. Despite a six-fold national increase in the incidence of ehrlichiosis over the past 20 years, recent data on the prevalence and manifestations of neuro-ehrlichiosis are lacking. Methods: We conducted a retrospective chart review of all patients tested for ehrlichiosis at University of North Carolina Health facilities between 2018 and 2021 and identified patients who met epidemiological criteria for ehrlichiosis as established by the Council of State and Territorial Epidemiologists and employed by the Centers for Disease Control and Prevention. We estimated the prevalence of neurological symptoms and described the spectrum of neurological manifestations in acute ehrlichiosis, documenting select patient cases in more detail in a case series. Results: Out of 55 patients with confirmed or probable ehrlichiosis, five patients (9.1%) had neurologic symptoms, which is notably lower than previous estimates. Neurological presentations were highly variable and included confusion, amnesia, seizures, focal neurological deficits mimicking ischemic vascular events, and an isolated cranial nerve palsy, though all patients had unremarkable neuroimaging at time of presentation. All but one patient had risk factors for severe ehrlichiosis (i.e., older age, immunosuppression). Conclusions: Neuro-ehrlichiosis may lack unifying patterns in clinical presentation that would otherwise aid in diagnosis. Clinicians should maintain a high index of suspicion for neuro-ehrlichiosis in patients with acute febrile illness, diverse neurological symptoms, and negative neuroimaging in lone star tick endemic regions. Key points: Ehrlichiosis can progress to involve the central nervous system but may present without unifying patterns of neurological symptoms. Increased awareness of the broad spectrum of clinical presentations in neuro-ehrlichiosis is imperative to facilitate prompt diagnosis and treatment. [ABSTRACT FROM AUTHOR]