Amanda Hempel

Background: Viral hemorrhagic fevers (VHFs) are severe, often high-consequence, life-threatening illnesses characterized by systemic disease, hemorrhage, and high mortality. The American Society of Tropical Medicine and Hygiene (ASTMH) Annual Meeting functions as a major international forum for the presentation of emerging data on infectious diseases, including novel pharmacologic and biologic interventions for VHF. However, while ASTMH presentations provide timely and high-impact insights, there is no efficient, consolidated synthesis of this rapidly evolving evidence base. Given the acute, outbreak-prone nature of VHF and the need for rapid translation of emerging data into clinical and public health practice, a structured synthesis of these data is warranted. Methods: This systematic review follows PRISMA guidelines and is limited to presentations delivered at the ASTMH Annual Meeting in Toronto (9–13 November 2025) in order to capture evolving evidence as it has emerged. Studies of all designs evaluating vaccines, chemoprophylactic agents, or targeted biological therapies for the prevention or treatment of VHF in adults and children were included. Data were extracted on incidence of VHF among exposed populations, safety, toxicity, and tolerability of preventive and therapeutic interventions, and morbidity and mortality outcomes among treated individuals. Secondary outcomes include hospitalization length-of-stay, economic outcomes, and measures of feasibility, acceptability, accessibility, and health equity. Results: Nine studies (four oral presentations, two poster presentations, and three hand-searched references) were included in the final synthesis. Seven studies evaluated pharmacologic preventive interventions and two evaluated experimental pharmacotherapeutics, with two studies contributing evidence to both categories. One observational study and one narrative review provided contextual evidence on vaccine readiness and outbreak preparedness. Discussion/Conclusions: This systematic review provides a rapid, structured synthesis of targeted medical interventions as emerging evidence at an expert scientific venue, while addressing the current lack of a consolidated, accessible summary of emerging VHF evidence. By rapidly organizing and evaluating these data, this work facilitates timely interpretation and application in clinical and public health settings where rapid decision-making is critical.

Manchineel dermatitis, caused by the sap of the manchineel tree native to the coastlands of the Caribbean, West Africa, and Central America, has received limited attention in the literature despite significant morbidity. The toxic sap causes a burning, blistering rash and conjunctivitis, while ingestion of the fruit may lead to oropharyngeal pain, hemodynamic instability, and gastrointestinal distress. Tourists unfamiliar with the manchineel tree may be exposed through exposure to the tree’s sap, contaminated rainwater, or ingestion of the apple-like fruit. We herein present a case of a patient who experienced prolonged symptoms of manchineel toxicity after ingestion of the manchineel fruit for several weeks. Antihistamines, corticosteroids, and a PPI were ineffective. The symptoms eventually resolved after discarding clothing and towels that had come in contact with the tree, raising the possibility that toxins may linger on fabrics. Travellers to regions in the Caribbean or Central America are at particular risk for toxicity from the Manchineel tree if unfamiliar with the associated dangers and should be counselled to avoid contact with the tree or ingesting any unfamiliar fruit on the ground. When exposures do occur, it may be reasonable to dispose of potentially contaminated fabrics to avoid recurrent exposures, particularly if recurrent symptoms are observed, as in our patient. We further contextualize manchineel toxicity within a comparative review of select tropical foodborne intoxications of plant origin (ackee, lychee, cassava, papain) and marine origin (ciguatera, scombroid, neurotoxic and diarrhetic shellfish poisonings, tetrodotoxin), distinguishing manchineel’s local irritant mechanism from the systemic toxidromes of these comparators and underscoring the absence of a specific antidote.

In 2025, tropical medicine was shaped by advances in diagnostic technology, expanding arboviral epidemics, rapid progress in filovirus vaccine development, evolving regulatory responses to newly licensed vaccines, and translational breakthroughs addressing neglected tropical diseases. This review discusses five select developments that significantly influenced clinical practice and global health policy over the past year, highlighting the implications of each for clinicians, researchers, and public health systems.

Introduction: There have been consistent reports of tension between the dual goals of assessment of learning and assessment for learning in competency‐based medical education. This is exemplified by assessments of Entrustable Professional Activities where trainees report a focus on assessment of learning and engaging in performance‐oriented behaviours that undermine meaningful assessment. It has been proposed that fostering a growth mindset amongst trainees may encourage use of EPA assessments for learning. This study aimed to explore how trainee mindset interacts with their perception of the role of EPAs in assessment of and for learning. Methods: We conducted 19 semi‐structured interviews of residents enrolled in 12 Canadian specialty post‐graduate programmes. Interviews explored residents' experiences with EPAs and their views on how tasks are learned. Transcripts were analysed using reflexive thematic analysis to generate themes. Results: Though most participants described attitudes of a growth mindset and a desire to learn from failure, a minority described attitudes associated with a fixed mindset contributing to avoidance of unsuccessful EPA assessments, suggesting mindset may impact the use of EPA assessments for learning. However, even amongst residents expressing views consistent with a growth mindset, the lack of meaningful feedback on EPA assessments prevented them from being a tool for learning. Participants described a variety of system factors that undermined provision of meaningful feedback and a view that programmes utilised EPA assessments only as a checkbox. Discussion: Even if a growth mindset may promote assessment for learning, a system that results in poor‐quality feedback turns EPA‐based assessments into an assessment of learning. An assessment system that supports both a culture of growth mindset and high quality of feedback is needed if EPA assessments are to be utilised for assessment for learning.

Given the overlap of epidemiological and clinical presentations of both rickettsioses and malaria infections, diagnostic testing where malaria is confirmed or excluded, without subsequent rickettsial testing, specifically in the case of Plasmodium vivax or P. ovale infection, may mask the possibility of relapse. A lack of clinical suspicion of co-infections, absence of knowledge on the geographic distribution of diseases, and lack of availability of point-of-care diagnostic testing for other tropical diseases can often lead to missed diagnosis or misdiagnosis of common tropical infections, including rickettsioses. We herein describe a case of confirmed intercurrent rickettsial and P. vivax infection, with the former potentially triggering a relapse of the latter in a febrile traveler returning to Canada from South America, and review the literature on tropical coinfections in returning travelers.

We conducted a retrospective cohort study to identify factors influencing intravenous (IV) versus oral antibiotic therapy in first-episode prosthetic joint infections. Of the 34/78 (44%) cases treated intravenously, negative cultures (26%), concomitant infections necessitating IV antibiotics (21%), and delays in susceptibility testing (15%) were the most common reasons for IV therapy.

Background: Bartonella henselae is a species of intracellular bacteria transmitted to humans through animal bites and scratches contaminated with the feces of arthropod vectors, and are most commonly associated with cat exposure although transmission from other mammals has been reported. Bartonella henselae infection has a spectrum of clinical manifestations and has rarely been reported as cause of hemophagocytic lymphohistiocytosis (HLH) in immunocompromised hosts. Case presentation: We present a report of Bartonella henselae infection progressing to HLH in an immunocompetent patient. The patient initially presented with regional lymphadenopathy but the diagnosis was not suspected as the patient reported no exposure to cats. On further history, he did report a scratch from a dog prior to development of symptoms. The patient was treated with methylprednisolone, intravenous immunoglobulin and anakinra for the HLH and three months of Doxycycline for Bartonella infection, with complete resolution of symptoms. Conclusions: Although commonly associated with cat exposure, Bartonella henselae transmission can occur after exposure to other animals and vectors including dogs and clinicians need to maintain an index of suspicion for timely diagnosis. Bartonella henselae is associated with a spectrum of clinical manifestations which can include disseminated infection with severe complications such as hemophagocytic lymphohistiocytosis. Prompt initiation of Bartonella treatment is essential when thought to be the trigger for hemophagocytic lymphohistiocytosis although the optimal treatment regimen is unclear.

BACKGROUND: Bartonella henselae are intracellular bacteria transmitted to humans through animal bites and scratches contaminated with the feces of arthropod vectors, and are most commonly associated with cat exposure although transmission from other mammals has been reported. Bartonella henselae infection has a spectrum of clinical manifestations and has rarely been reported as cause of hemophagocytic lymphohistiocytosis (HLH) in immunocompromised hosts. CASE PRESENTATION: We present a report of Bartonella henselae infection progressing to HLH in an immunocompetent host. The patient initially presented with regional lymphadenopathy but the diagnosis was not suspected as the patient reported no exposure to cats. On further history, he did report a scratch from a dog prior to development of symptoms. The patient was treated with methylprednisolone, intravenous immunoglobulin and anakinra for the HLH and three months of Doxycycline for Bartonella infection, with complete resolution of symptoms. CONCLUSIONS: Although commonly associated with cat exposure, Bartonella henselae transmission can occur after exposure to other animals including dogs and clinicians need to maintain an index of suspicion for timely diagnosis. Bartonella henselae is associated with a spectrum of clinical manifestations which can include disseminated infection with severe complications such as hemophagocytic lymphohistiocytosis. Prompt initiation of Bartonella treatment is essential when thought to be the trigger for hemophagocytic lymphohistiocytosis although the optimal treatment regimen is unclear.