In the United States in 2021, an outbreak of 4 cases of Burkholderia pseudomallei, the etiologic agent of melioidosis and a Tier One Select Agent (potential for deliberate misuse and subsequent harm), resulted in 2 deaths. The causative strain, B. pseudomallei ATS2021, was unintentionally imported into the United States in an aromatherapy spray manufactured in India.
View Article and Find Full Text PDFYersinia pestis, the causative agent of plague and a biological threat agent, presents an urgent need for novel medical countermeasures due to documented cases of naturally acquired antibiotic resistance and potential person-to-person spread during a pneumonic infection. Immunotherapy has been proposed as a way to circumvent current and future antibiotic resistance. Here, we describe the development and characterization of two affinity matured human antibodies (αF1Ig AM2 and αF1Ig AM8) that promote survival of mice after exposure to aerosolized Y.
View Article and Find Full Text PDFis one of the several biothreat agents for which a licensed vaccine is needed. To ensure vaccine protection is achieved across a range of virulent strains, we assembled and characterized a panel of isolates to be utilized as challenge strains. A promising tularemia vaccine candidate is rLVS Δ/ (rLVS), in which the vector is the LVS strain with a deletion in the gene and which additionally expresses a fusion protein comprising immunodominant epitopes of proteins IglA, IglB, and IglC.
View Article and Find Full Text PDFis a gram-negative bacterium that causes plague in animals and humans. Depending on the route of disease transmission, the bacterium can cause an acute, often fatal disease that has a narrow window for treatment with antibiotics. Additionally, antibiotic resistant strains have been identified, emphasizing the need for novel treatments.
View Article and Find Full Text PDFPlague is an ancient disease that continues to be of concern to both the public health and biodefense research communities. Pneumonic plague is caused by hematogenous spread of bacteria from a ruptured bubo to the lungs or by directly inhaling aerosolized bacteria. The fatality rate associated with pneumonic plague is significant unless effective antibiotic therapy is initiated soon after an early and accurate diagnosis is made.
View Article and Find Full Text PDFObjectives: To evaluate the in vitro activity and in vivo efficacy of delafloxacin against Bacillus anthracis, the causative agent of anthrax.
Methods: MICs were obtained according to CLSI guidelines for 30 virulent isolates and 14 attenuated antibiotic-resistant strains. For the in vivo efficacy study, mice were administered delafloxacin (30-62.
The microbial pathogens and are unrelated bacteria, yet both are the etiologic agents of naturally occurring diseases in animals and humans and are classified as Tier 1 potential biothreat agents. is the gram-negative bacterial agent of melioidosis, a major cause of sepsis and mortality globally in endemic tropical and subtropical regions. is the gram-positive spore-forming bacterium that causes anthrax.
View Article and Find Full Text PDF, the gram-negative bacterium that causes melioidosis, is notoriously difficult to treat with antibiotics. A significant effort has focused on identifying protective vaccine strategies to prevent melioidosis. However, when used as individual medical countermeasures both antibiotic treatments (therapeutics or post-exposure prophylaxes) and experimental vaccine strategies remain partially protective.
View Article and Find Full Text PDFand the closely related species, , produce similar multifaceted diseases which range from rapidly fatal to protracted and chronic, and are a major cause of mortality in endemic regions. Besides causing natural infections, both microbes are Tier 1 potential biothreat agents. Antibiotic treatment is prolonged with variable results, hence effective vaccines are urgently needed.
View Article and Find Full Text PDFThe purpose of this case report is to describe spasticity and encephalopathy that developed in a multiple sclerosis patient following carbapenem administration. A 55-year-old female with multiple sclerosis developed spasticity and encephalopathy within 24 hours of meropenem and ertapenem administration. This was the second time that she had developed encephalopathy following carbapenem administration.
View Article and Find Full Text PDFis an infectious bacterium of clinical and biodefense concern, and is the causative agent of melioidosis. The mortality rate can reach up to 50% and affects 165,000 people per year; however, there is currently no vaccine available. In this study, we examine the antigen-specific immune response to a vaccine formulated with antigens derived from an outer membrane protein in , Bucl8.
View Article and Find Full Text PDFRelatively recent advances in plague vaccinology have produced the recombinant fusion protein F1-V plague vaccine. This vaccine has been shown to readily protect mice from both bubonic and pneumonic plague. The protection afforded by this vaccine is solely based upon the immune response elicited by the F1 or V epitopes expressed on the F1-V fusion protein.
View Article and Find Full Text PDFis one of several biothreat agents for which a licensed vaccine is needed to protect against this pathogen. To aid in the development of a vaccine protective against pneumonic tularemia, we generated and characterized a panel of isolates that can be used as challenge strains to assess vaccine efficacy. Our panel consists of both historical and contemporary isolates derived from clinical and environmental sources, including human, tick, and rabbit isolates.
View Article and Find Full Text PDFObjectives: The primary endpoint was to determine the sensitivity and specificity of the bronchoalveolar lavage Gram stain in predicting culture results. Secondary endpoints included determining the proportion of Gram stains from bronchoalveolar lavages that accurately identify culture isolates and the duration of antibiotic treatment before bronchoalveolar lavage collection.
Design: Retrospective, observational study.
The etiologic agent of plague, , is a globally distributed pathogen which poses both a natural and adversarial threat. Due largely to the rapid course and high mortality of pneumonic plague, vaccines are greatly needed. Two-component protein vaccines have been unreliable and potentially vulnerable to vaccine resistance.
View Article and Find Full Text PDFFailure of an existing effluent decontamination system (EDS) prompted the consideration of commercial off-the-shelf solutions for decontamination of containment laboratory waste. A bleach-based chemical EDS was purchased to serve as an interim solution. Studies were conducted in the laboratory to validate inactivation of spores with bleach in complex matrices containing organic simulants including fetal bovine serum, humic acid, and animal room sanitation effluent.
View Article and Find Full Text PDFMelioidosis, caused by the Gram-negative bacterium Burkholderia pseudomallei, is a major cause of sepsis and mortality in endemic regions of Southeast Asia and Northern Australia. B. pseudomallei is a potential bioterrorism agent due to its high infectivity, especially via inhalation, and its inherent resistance to antimicrobials.
View Article and Find Full Text PDFAnthrax is a major zoonotic disease of wildlife, and in places like West Africa, it can be caused by Bacillus anthracis in arid nonsylvatic savannahs, and by B. cereus biovar anthracis (Bcbva) in sylvatic rainforests. Bcbva-caused anthrax has been implicated in as much as 38% of mortality in rainforest ecosystems, where insects can enhance the transmission of anthrax-causing bacteria.
View Article and Find Full Text PDFBackground: Inhalational anthrax is rare and clinical experience limited. Expert guidelines recommend treatment with combination antibiotics including protein synthesis-inhibitors to decrease toxin production and increase survival, although evidence is lacking.
Methods: Rhesus macaques exposed to an aerosol of Bacillus anthracis spores were treated with ciprofloxacin, clindamycin, or ciprofloxacin + clindamycin after becoming bacteremic.
Mouse models have been used to generate critical data for many infectious diseases. In the case of , mouse models have been invaluable for bacterial pathogenesis studies as well as for testing novel medical countermeasures including both vaccines and therapeutics. Mouse models of melioidosis have also provided a possible way forward to better understand the chronicity associated with this infection, as it appears that BALB/c mice develop an acute infection with , whereas the C57BL/6 model is potentially more suggestive of a chronic infection.
View Article and Find Full Text PDFThe misuse of infectious disease pathogens as agents of deliberate attack on civilians and military personnel is a serious national security concern, which is exacerbated by the emergence of natural or genetically engineered multidrug resistant strains. In this study, the therapeutic potential of combinations of an antibiotic and a broad-spectrum antimicrobial peptide (AMP) was evaluated against five bacterial biothreats, the etiologic agents of glanders (Burkholderia mallei), melioidosis (Burkholderia pseudomallei), plague (Yersinia pestis), tularemia (Francisella tularensis), and anthrax (Bacillus anthracis). The therapeutics included licensed early generation antibiotics which are now rarely used.
View Article and Find Full Text PDFThe administration of antipyretic analgesics prior to, in conjunction with, or due to sequelae associated with vaccination is a common yet somewhat controversial practice. In the context of human vaccination, it is unclear if even short-term analgesic regimens can significantly alter the resulting immune response, as literature exists to support several scenarios including substantial immune interference. In this report, we used a live attenuated vaccine to examine the impact of analgesic administration on the immune response elicited by a single dose of a live bacterial vaccine in mice.
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