Mpox in the Emergency Department: A Case Series.

Introduction: We sought to describe the demographic characteristics, clinical features, and outcomes of a cohort of patients who presented to our emergency departments with mpox (formerly known as monkeypox) infection between May 1-August 1, 2022. Case Series: We identified 145 patients tested for mpox, of whom 79 were positive. All positive cases were among cisgender men, and the majority (92%) were among men who have sex with men. A large number of patients (39%) were human immunodeficiency virus (HIV) positive. There was wide variation in emergency department (ED) length of stay (range 2-16 hours, median 4 hours) and test turnaround time (range 1-11 days, median 4 days). Most patients (95%) were discharged, although a substantial proportion (22%) had a return visit within 30 days, and 28% ultimately received tecrovirimat. Conclusion: Patients who presented to our ED with mpox had similar demographic characteristics and clinical features as those described in other clinical settings during the 2022 outbreak. While there were operational challenges to the evaluation and management of these patients, demonstrated by variable lengths of stay and frequent return visits, most were able to be discharged.

Optimization of lag phase shapes the evolution of a bacterial enzyme.

Mutations provide the variation that drives evolution, yet their effects on fitness remain poorly understood. Here we explore how mutations in the essential enzyme adenylate kinase (Adk) of Escherichia coli affect multiple phases of population growth. We introduce a biophysical fitness landscape for these phases, showing how they depend on molecular and cellular properties of Adk. We find that Adk catalytic capacity in the cell (the product of activity and abundance) is the major determinant of mutational fitness effects. We show that bacterial lag times are at a well-defined optimum with respect to Adk's catalytic capacity, while exponential growth rates are only weakly affected by variation in Adk. Direct pairwise competitions between strains show how environmental conditions modulate the outcome of a competition where growth rates and lag times have a tradeoff, shedding light on the multidimensional nature of fitness and its importance in the evolutionary optimization of enzymes.