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In July 2017, fever and sepsis developed in 3 recipients of solid organs (1 heart and 2 kidneys) from a common donor in the United States; 1 of the kidney recipients died. Tularemia was suspected only after blood cultures from the surviving kidney recipient grew Francisella species. The organ donor, a middle-aged man from the southwestern United States, had been hospitalized for acute alcohol withdrawal syndrome, pneumonia, and multiorgan failure. F. tularensis subsp. tularensis (clade A2) was cultured from archived spleen tissue from the donor and blood from both kidney recipients. Whole-genome multilocus sequence typing indicated that the isolated strains were indistinguishable. The heart recipient remained seronegative with negative blood cultures but had been receiving antimicrobial drugs for a medical device infection before transplant. Two lagomorph carcasses collected near the donor's residence were positive by PCR for F. tularensis subsp. tularensis (clade A2). This investigation documents F. tularensis transmission by solid organ transplantation. [ABSTRACT FROM AUTHOR]

We examined 5 tularemia cases in Arizona, USA, during 2015-2017. All were caused by Francisella tularensis group A.II. Genetically similar isolates were found across large spatial and temporal distances, suggesting that group A.II strains are dispersed across long distances by wind and exhibit low replication rates in the environment. [ABSTRACT FROM AUTHOR]

Background: The intentional release of Bacillus anthracis in the United States in 2001 has heightened concern about the use of pathogenic microorganisms in bioterrorism attacks. Many of the deadliest bacteria, including the Class A Select Agents Bacillus anthracis, Francisella tularensis, and Yersinia pestis, are highly infectious via the pulmonary route when released in aerosolized form. Hence, rapid, sensitive, and reliable methods for detection of these biothreats and characterization of their potential impact on the exposed population are of critical importance to initiate and support rapid military, public health, and clinical responses. Methodology/Principal Findings: We have developed microfluidic multiplexed PCR and sequencing assays based on the simultaneous interrogation of three pathogens per assay and ten loci per pathogen. Microfluidic separation of amplified fluorescently labeled fragments generated characteristic electrophoretic signatures for identification of each agent. The three sets of primers allowed significant strain typing and discrimination from non-pathogenic closely-related species and environmental background strains based on amplicon sizes alone. Furthermore, sequencing of the 10 amplicons per pathogen, termed “Rapid Focused Sequencing,” allowed an even greater degree of strain discrimination and, in some cases, can be used to determine virulence. Both amplification and sequencing assays were performed in microfluidic biochips developed for fast thermal cycling and requiring 7 µL per reaction. The 30-plex sequencing assay resulted in genotypic resolution of 84 representative strains belonging to each of the three biothreat species. Conclusions/Significance: The microfluidic multiplexed assays allowed identification and strain differentiation of the biothreat agents Bacillus anthracis, Francisella tularensis, and Yersinia pestis and clear discrimination from closely-related species and several environmental background strains. The assays may be extended to detect a large number of pathogens, are applicable to the evaluation of both environmental and clinical samples, and have the potential to be applied in military, public health, and clinical diagnostic settings. [ABSTRACT FROM AUTHOR]

Tularemia in the United States is caused by 2 subspecies of Francisella tularensis, subspecies tularensis (type A) and subspecies holarctica (type B). We compared clinical and demographic features of human tularemia cases from 1964 to 2004 from 39 states in which an isolate was recovered and subtyped. Our data indicate that type A and type B infections differ with respect to affected populations, anatomic site of isolation, and geographic distribution. Molecular subtyping with pulsed-field gel electrophoresis further defined 2 subpopulations of type A (type A-east and type A-west) that differ with respect to geographic distribution, disease outcome, and transmission. Our data suggest that type A-west infections are less severe than either type B or type A-east infections. Through a combined epidemiologic and molecular approach to human cases of tularemia, we provide new insights into the disease for future investigation. [ABSTRACT FROM AUTHOR]

The causative agent of tularemia, Francisella tularensis, is a formidable biologic agent that occurs naturally throughout North America. We examined genetic and spatial diversity patterns among 161 US F. tularensis isolates by using a 24-marker multiple-locus variable-number tandem repeat analysis (MLVA) system. MLVA identified 126 unique genotypes. Phylogenetic analyses showed patterns similar to recently reported global-scale analyses. We observed clustering by subspecies, low genetic diversity within F. tularensis subsp. holarctica, and division of F. tularensis subsp. tularensis into 2 distinct subpopulations: A.I. and A.II. The 2 F. tularensis subsp. tularensis subpopulations also represent geographically distinct groups; A.I. occurs primarily in the central United States, and A.II. occurs primarily in the western United States. These spatial distributions are correlated with geographic ranges of particular vectors, hosts of tularemia, and abiotic factors. These correlates provide testable hypotheses regarding ecologic factors associated with maintaining tularemia foci. [ABSTRACT FROM AUTHOR]

Summarizes clinical and epidemiologic information from the tularemia cases reported in Oklahoma in June 2000. Classifications of the cases; Median age of tularemia patients; Francisella tularensis virus isolated from patients; Potential Francisella tularensis exposures for nonfatal cases; Description on the tularemia cases reported; Transmission mechanism of the virus.

Examines the correlation between lawn mowing and primary pneumonic tularemia outbreak in Cape Cod, Massachusetts. Details on the study conducted by the Centers for Disease Control and Prevention; Prevalence of Francisella tularensis A in the blood stream of tularemia infected patients; Clinical manifestations of tularemia.