A Taxonomically-informed Mass Spectrometry Search Tool for Microbial Metabolomics Data

MicrobeMASST, a taxonomically-informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbial-derived metabolites and relative producers, without a priori knowledge, will vastly enhance the understanding of microorganisms’ role in ecology and human health

Population-level Characterization of Nocardiosis in the United States

Nocardiosis is caused by opportunistic, soil-borne bacteria in the genus Nocardia. The disease is characterized by severe pulmonary and systemic infections, and mild to severe skin infections. People thought to be at risk are older adults and those with underlying comorbidities, particularly immunosuppressive conditions. Treatment duration can be long and may require antimicrobial and surgical interventions. Considered a rare disease, the existing literature and knowledge base regarding the clinical presentation, persons at risk, incidence, and mortality estimates are primarily from case series or limited hospital-based retrospective analyses. Evaluating the disease characteristics from more generalizable data can aid in our understanding of the disease and may aid in identifying persons who may be at greater risk of death. The purpose of this dissertation is to use population-level administrative data to develop generalizable estimates of the incidence and mortality, and to evaluate risk factors, including identifying a predictive comorbidity measure. The 100% Medicare Fee-For-Service data, and the Healthcare Utilization Project’s State Inpatient Databases and State Ambulatory and Surgery and Services Databases were used to evaluate nocardiosis among Medicare beneficiaries as well as all payer hospitalization and visit discharges. The demographics, costs, visits, and risk factors are described from each data source, and incidence and hospitalization rates are calculated. Comorbidity measures are evaluated for prediction of mortality. Time to death and covariates associated with mortality are calculated from the person-based longitudinal Medicare data and the HCUP hospital visit-based data, respectively. The findings of this dissertation describe nocardiosis that can be generalized to all Fee-for-Service Medicare beneficiaries and almost half the US population. Nocardiosis cases and nocardiosis-associated visits were more often male, older, and sicker than the general Medicare and US populations. Mortality was associated with disseminated nocardiosis, cerebrovascular disease, and the presence of additional comorbid conditions, when controlling for other factors. Additional findings will be discussed. These findings can provide additional insight into persons who may be at greater risk of developing nocardiosis and can provide clinicians with factors that are associated with mortality. These findings provide a baseline from which future population-level analyses can be compared

Leptospirosis-Associated Hospitalizations, United States, 1998–2009

A small percentage of persons with leptospirosis, a reemerging zoonosis, experience severe complications that require hospitalization. The number of leptospirosis cases in the United States is unknown. Thus, to estimate the hospitalization rate for this disease, we analyzed US hospital discharge records for 1998–2009 for the total US population by using the Nationwide Inpatient Sample. During that time, the average annual rate of leptospirosis-associated hospitalizations was 0.6 hospitalizations/1,000,000 population. Leptospirosis-associated hospitalization rates were higher for persons >20 years of age and for male patients. For leptospirosis-associated hospitalizations, the average age of patients at admission was lower, the average length of stay for patients was longer, and hospital charges were higher than those for nonleptospirosis infectious disease–associated hospitalizations. Educating clinicians on the signs and symptoms of leptospirosis may result in earlier diagnosis and treatment and, thereby, reduced disease severity and hospitalization costs

What Is Anthrax?

Anthrax has been feared for its high mortality in animals and humans for centuries. The etiologic agent is considered a potentially devastating bioweapon, and since 1876―when Robert Koch demonstrated that Bacillus anthracis caused anthrax―it has been considered the sole cause of the disease. Anthrax is, however, a toxin-mediated disease. The toxins edema toxin and lethal toxin are formed from protein components encoded for by the pXO1 virulence plasmid present in pathogenic B. anthracis strains. However, other members of the Bacillus cereus group, to which B. anthracis belongs, have recently been shown to harbor the pXO1 plasmid and produce anthrax toxins. Infection with these Bacillus cereus group organisms produces a disease clinically similar to anthrax. This suggests that anthrax should be defined by the exotoxins encoded for by the pXO1 plasmid rather than the bacterial species it has historically been associated with, and that the definition of anthrax should be expanded to include disease caused by any member of the B. cereus group containing the toxin-producing pXO1 plasmid or anthrax toxin genes specifically

A Case-Study of Implementation of Improved Strategies for Prevention of Laboratory-acquired Brucellosis

Background: In 2012, the Alaska Section of Epidemiology investigated personnel potentially exposed to a Brucella suis isolate as it transited through three laboratories. Methods: We summarize the first implementation of the United States Centers for Disease Control and Prevention 2013 revised recommendations for monitoring such exposures: (1) risk classification; (2) antimicrobial postexposure prophylaxis; (3) serologic monitoring; and (4) symptom surveillance. Results: Over 30 people were assessed for exposure and subsequently monitored for development of illness. No cases of laboratory-associated brucellosis occurred. Changes were made to gaps in laboratory biosafety practices that had been identified in the investigation. Conclusion: Achieving full compliance for the precise schedule of serologic monitoring was challenging and resource intensive for the laboratory performing testing. More refined exposure assessments could inform decision making for follow-up to maximize likelihood of detecting persons at risk while not overtaxing resources

Development of the Global Mycetoma Working Group

The Global Mycetoma Working Group (GMWG) was formed in January 2018 in response to the declaration of mycetoma as a neglected tropical disease (NTD) by the World Health Assembly. The aim of the working group is to connect experts and public health practitioners around the world to accelerate mycetoma prevention activities and reduce the impact of mycetoma on patients, healthcare providers and society in the endemic regions. The working group has made tangible contributions to mycetoma programming, awareness and coordination among scientists, clinicians and public health professionals. The group's connectivity has enabled rapid response and review of NTD documents in development, has created a network of public health professionals to provide regional mycetoma expertise and has enabled mycetoma to be represented within broader NTD organizations. The GMWG will continue to serve as a hub for networking and building collaborations for the advancement of mycetoma clinical management and treatment, research and public health programming

Knowledge, attitudes, and practices related to anthrax and animal care: A case-control study in Georgia.

INTRODUCTION:Anthrax is endemic in Georgia and recent outbreaks prompted a livestock-handler case-control study with a component to evaluate anthrax knowledge, attitudes, and practices (KAP) among livestock handlers or owners. METHODS:Cases were handlers of livestock with confirmed animal anthrax from June 2013-May 2015. Handlers of four matched unaffected animals were selected as controls, two from the same village as the case animal ("village control") and two from 3-10 km away ("area control"). Descriptive statistics were reported and conditional logistic regression was performed to estimate the magnitude of the association of cases with specific study KAP factors. RESULTS:Cases were more likely male, had lower level college education, less animal care experience, and provided more animal care to their cattle. Cases had lower odds of burying a suddenly dead animal compared to all controls (Odds Ratio [OR]: 0.32, 95% Confidence interval [CI]:0.12, 0.88) and area controls (OR: 0.32, 95% CI: 0.11, 0.91). On an 8-point knowledge scale, cases having an animal with anthrax had a 1.31 times greater knowledge score compared to all controls (95% CI: 1.03, 1.67). Cases had higher odds of ever having human anthrax or knowing another person who had anthrax compared to all controls (OR: 4.56, 95% CI: 1.45, 14.30) and area controls (OR: 7.16, 95% CI: 1.52, 33.80). DISCUSSION:Cases were more knowledgeable of anthrax and had better anthrax prevention practices, but these are likely a result of the case investigation and ring vaccination following the death of their animal. CONCLUSIONS:The findings reveal a low level of knowledge and practices related to anthrax control and prevention, and will guide educational material development to fill these gaps

Case Series of Fatal Leptospira spp./Dengue Virus Co-Infections—Puerto Rico, 2010–2012

Co-infection with pathogens that cause acute febrile illness creates a diagnostic challenge as a result of overlapping clinical manifestations. Here, we describe four fatal cases of Leptospira species/dengue virus co-infection in Puerto Rico. Although all patients sought care early, antibiotic administration was delayed for most. Steroids were administered to all patients, in most cases before antibiotics. These cases show the need for clinicians evaluating patients in or recently returned from the tropics with acute febrile illness to consider both dengue and leptospirosis. Furthermore, they illustrate the need for nucleic acid- or antigen-based rapid diagnostic tests to enable timely patient diagnosis and management. In particular, antibiotic therapy should be initiated early for patients with suspected leptospirosis, and steroids should not be administered to patients with suspected dengue