BACKGROUND: Tick-borne pathogens (TBPs) constitute an emerging threat to public and animal health especially in the African continent, where land-use change, and wildlife loss are creating new opportunities for disease transmission. A review of TBPs with a focus on ticks determined the epidemiology of Rhipicephalus ticks in heartwater and the affinity of each Rickettsia species for different tick genera. We conducted a systematic review and meta-analysis to collect, map and estimate the molecular prevalence of Anaplasmataceae, Rickettsiaceae and Coxiellaceae in African wildlife.
METHODS: Relevant scientific articles were retrieved from five databases: PubMed, ScienceDirect, Scopus, Ovid and OAIster. Publications were selected according to pre-determined exclusion criteria and evaluated for risk of bias using the appraisal tool for cross-sectional studies (AXIS). We conducted an initial descriptive analysis followed by a meta-analysis to estimate the molecular prevalence of each pathogen. Subgroup analysis and meta-regression models were employed to unravel associations with disease determinants. Finally, the quality of evidence of every estimate was finally assessed.
RESULTS: Out of 577 retrieved papers, a total of 41 papers were included in the qualitative analysis and 27 in the meta-analysis. We retrieved 21 Anaplasmataceae species, six Rickettsiaceae species and Coxiella burnetii. Meta-analysis was performed for a total of 11 target pathogens. Anaplasma marginale, Ehrlichia ruminantium and Anaplasma centrale were the most prevalent in African bovids (13.9 %, CI: 0-52.4 %; 20.9 %, CI: 4.1-46.2 %; 13.9 %, CI: 0-68.7 %, respectively). Estimated TBPs prevalences were further stratified per animal order, family, species and sampling country.
CONCLUSIONS: We discussed the presence of a sylvatic cycle for A. marginale and E. ruminantium in wild African bovids, the need to investigate A. phagocytophilum in African rodents and non-human primates as well as E. canis in the tissues of wild carnivores, and a lack of data and characterization of Rickettsia species and C. burnetii.
CONCLUSIONS: Given the lack of epidemiological data on wildlife diseases, the current work can serve as a starting point for future epidemiological and/or experimental studies.

Rickettsia africae is a tick-borne bacteria known to cause African tick bite fever (ATBF). While the disease was first described more than 100 years ago, knowledge of transmission risk factors and disease burden remain poorly described. To better understand the burden of R. africae, this article reviewed and summarized the published literature related to ATBF epidemiology and clinical management. Using a systematic approach, consistent with the PRISMA guidelines, we identified more than 100 eligible articles, including 65 epidemiological studies and 41 case reports. Most reports described R. africae in ticks and livestock, while human studies were less common. Human disease case reports were exclusively among returning travellers from non-endemic areas, which limits our disease knowledge among at-risk populations: people living in endemic regions. Substantial efforts to elucidate the ATBF risk factors and clinical manifestations among local populations are needed to develop effective preventative strategies and facilitate appropriate and timely diagnosis.

BACKGROUND: Severe Fever with Thrombocytopenia Syndrome (SFTS) is a tick-borne disease caused by the SFTS virus (SFTSV) which has the potential to become a pandemic and is currently a major public health concern.
METHODS: We present the case of a 74-year-old female from an urban area of Chongqing, with leukocytopenia, thrombocytopenia, organ function, inflammatory, blood coagulation, and immune abnormalities. SFTSV infection was confirmed through molecular detection and metagenomic next-generation sequencing (mNGS) analysis, indicating a diagnosis of SFTS due to the patient\'s history of tick bites. The patient received symptomatic and supportive therapy, including antibiotics, antiviral treatment, and antifungal therapy, and finally discharged from the hospital on day 18.
CONCLUSIONS: This study highlights the need for increased awareness, early diagnosis, and prompt treatment for tick-borne SFTS. It also provides a comprehensive understanding of the disease\'s characteristics, pathogenesis, detection methods, and available treatments.

Spotted fever group Rickettsia spp. (SFGR) are a large group of tick-borne bacteria causing important emerging and re-emerging diseases that affect animals and humans. While SFGR are found worldwide, a lack of surveillance and misdiagnosis particularly affect South American countries. Colombia is a high burdened country in South America, yet rickettsioses are not deemed a nationally reportable condition limiting disease-specific public health resources. As mortality rates are high for one Rickettsia pathogen species, there is a great need to better understand the epidemiological and ecological factors that increase SFGR transmission risk regionally. This literature review provides an overview of Colombia-based SFGR studies connecting knowledge about both vectors and hosts.

Hemophagocytic lymphohistiocytosis (HLH) secondary to tick-borne infections is a rare but potentially life-threatening syndrome. We performed a scoping review according to PRISMA guidelines to systematically analyze the existing literature on the topic. A total of 98 patients were included, with a mean age of 43.7 years, of which 64% were men. Most cases, 31%, were reported from the USA. Immunosuppression was present in 21.4%, with the most common cause being previous solid organ transplantation. Constitutional symptoms were the most common, observed in 83.7% of the patients, while fever was reported in 70.4% of cases. Sepsis was present in 27.6%. The most common laboratory abnormalities in this cohort were thrombocytopenia in 81.6% of patients, while anemia, leukopenia, and leukocytosis were observed in 75.5%, 55.1%, and 10.2%, respectively. Liver enzyme elevation was noted in 63.3% of cases. The H-score was analyzed in 64 patients, with the mean value being 209, and bone marrow analysis was performed in 61.2% of patients. Ehrlichia spp. was the main isolated agent associated with HLH in 45.9%, followed by Rickettsia spp. in 14.3% and Anaplasma phagocytophilum in 12.2%. Notably, no patient with Powassan virus infection or Lyme borreliosis developed HLH. The most common complications were acute kidney injury (AKI) in 35.7% of patients, shock with multiple organ dysfunction in 22.5%, encephalopathy/seizure in 20.4%, respiratory failure in 16.3%, and cardiac complications in 7.1% of patients. Treatment included antibiotic therapy alone in 43.9%, while 5.1% of patients were treated with immunosuppressants alone. Treatment with both antibiotics and immunosuppressants was used in 51% of patients. Appropriate empiric antibiotics were used in 62.2%. In 43.9% of cases of HLH due to tick-borne disease, patients received only antimicrobial therapy, and 88.4% of those recovered completely without the need for immunosuppressive therapy. The mortality rate in our review was 16.3%, and patients who received inappropriate or delayed empiric therapy had a worse outcome. Hence, we suggest empiric antibiotic treatment in patients who are suspected of having HLH due to tick-borne disease or in whom diagnostic uncertainty persists due to diagnostic delay in order to minimize mortality.

BACKGROUND: Antibiotic therapy for patients with early Lyme disease is necessary to prevent later-stage Lyme disease complications. This systematic review and meta-analysis compares shorter versus longer antibiotic regimens in treating early Lyme disease.
METHODS: A systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted up to November 2023. We examined treatment failure, complete response, and photosensitivity. Short vs. long therapy was defined as ≤10 days vs. >10 days. Subgroup analyses included antibiotic type and varying treatment durations. Analysis utilized RStudio 4.1.2. PROSPERO registration: CRD42023423876.
RESULTS: Seven studies, encompassing 1,462 patients, were analyzed. No significant differences in treatment failure, 12-month complete response, final visit complete response were found between short and long durations of antibiotic therapy. Subgroup and sensitivity analyses corroborated these findings.
CONCLUSIONS: Shorter and longer antibiotic regimens for early Lyme disease show similar efficacy, highlighting the potential of ≤10-day courses, as effective treatment options.

Three Asian longhorned ticks (Haemaphysalis longicornis) were collected on Staten Island, Richmond County, New York, in 2014-2015 as part of a tick-borne disease surveillance program conducted by the New York City Department of Health and Mental Hygiene and the Defense Centers of Public Health - Aberdeen Tick-Borne Disease Laboratory. These records mark the earliest known occurrence of H. longicornis in New York State outside of quarantine areas, predating previously reported detections by several years. Robust populations of H. longicornis were collected in subsequent years at the Staten Island site where these few ticks were found, demonstrating that small infestations have the potential to proliferate quickly. Haemaphysalis longicornis is a 3-host ixodid tick native to eastern Asia but now established in the United States, as well as Australasia and several Pacific islands. Although H. longicornis has not yet been associated with human disease transmission in the United States, it warrants attention as a potential vector, as it is demonstrated to harbor various pathogens of medical and veterinary interest across its native and introduced range.

Rocky Mountain spotted fever (RMSF) is a potentially lethal tick-borne disease caused by Rickettsia rickettsii, known for its tropism for vascular endothelial cells. Its classic symptoms include fever, headaches, and a rash, but atypical presentations can challenge diagnosis. We present the case of a 71-year-old male with fever, weakness, and hiccups, evolving into confusion. Laboratory findings showed severe hyponatremia, leukocytosis, and abnormal blood parameters. Initial management addressed sepsis and hyponatremia, leading to symptom improvement. Later, a fever of 106.5°F prompted ICU transfer, broad-spectrum antibiotics, and testing for tick-borne diseases. The patient reported tick exposure and received prophylactic doxycycline. Follow-up confirmed the RMSF diagnosis based on serological testing and clinical symptoms. This case highlights the diagnostic challenges posed by atypical RMSF presentations and underscores the importance of early detection and treatment to prevent complications.

Ticks are obligate, haematophagous arthropods that are distributed across the world, which may transmit more than 200 pathogens, including viruses, bacteria and parasites. A large number of tick species are widespread in China, and their transmitting tick-borne viral diseases pose a great threat to human health in endemic foci. This review describes the epidemiology of common, emerging and potentially pathogenic tick-borne viruses in China, and recommends the assessment of public health significance and pathogenicity of emerging tick-borne viruses using reverse microbial etiology, so as to provide insights into the management of emerging tick-borne diseases in China.
［摘要］ 蜱是一种呈全球性分布的体外吸血节肢动物, 可传播包 括病毒、细菌、寄生虫在内的200余种病原。我国蜱种类多、分布 广, 其传播的病毒性疾病给流行区广大人民群众身体健康造成了 严重威胁。本文概述了我国常见、新发及具有潜在致病性的蜱媒 病毒流行现状, 并建议利用反向病原学研究策略开展新发蜱媒病 毒公共卫生意义评估及致病性研究, 从而为我国新发蜱传疾病防 控提供参考。.

Tick-borne diseases (TBDs) have become a significant public health concern in the United States over the past few decades. The increasing incidence and geographical spread of these diseases have prompted the implementation of robust surveillance systems to monitor their prevalence, distribution, and impact on human health. This comprehensive review describes key disease features with the geographical distribution of all known tick-borne pathogens in the United States, along with examining disease surveillance efforts, focusing on strategies, challenges, and advancements. Surveillance methods include passive and active surveillance, laboratory-based surveillance, sentinel surveillance, and a One Health approach. Key surveillance systems, such as the National Notifiable Diseases Surveillance System (NNDSS), TickNET, and the Tick-Borne Disease Laboratory Network (TBDLN), are discussed. Data collection and reporting challenges, such as underreporting and misdiagnosis, are highlighted. The review addresses challenges, including lack of standardization, surveillance in non-human hosts, and data integration. Innovations encompass molecular techniques, syndromic surveillance, and tick surveillance programs. Implications for public health cover prevention strategies, early detection, treatment, and public education. Future directions emphasize enhanced surveillance networks, integrated vector management, research priorities, and policy implications. This review enhances understanding of TBD surveillance, aiding in informed decision-making for effective disease prevention and control. By understanding the current surveillance landscape, public health officials, researchers, and policymakers can make informed decisions to mitigate the burden of (TBDs).