Nontyphoidal salmonella bacteremia resulting in thoracic aortic dissection

An 84-year-old male retired boilermaker, residing in Australia, presented with the acute onset of anterior, left-sided, pleuritic chest pain. He had a history of ischemic heart disease, and had been on a long-haul flight, returning from Mauritius 9 days previously

NASA's Space Launch System: Systems Engineering Approach for Affordability and Mission Success

NASA is working toward the first launch of the Space Launch System, a new, unmatched capability for deep space exploration with launch readiness planned for 2019. Since program start in 2011, SLS has passed several major formal design milestones, and every major element of the vehicle has produced test and flight hardware. The SLS approach to systems engineering has been key to the program's success. Key aspects of the SLS SE&I approach include: 1) minimizing the number of requirements, 2) elimination of explicit verification requirements, 3) use of certified models of subsystem capability in lieu of requirements when appropriate and 4) certification of capability beyond minimum required capability

The Incidence, Aetiology and Clinical Course of Serious Infections Complicating Biological and Targeted Synthetic Disease-Modifying Antirheumatic Drug Therapy in Patients with Rheumatoid Arthritis in Tropical Australia

Introduction: Patients receiving biological and targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) for rheumatological conditions are at an increased risk of serious, potentially life-threatening, infection. However, the incidence, aetiology, and clinical course of serious infection in patients receiving b/tsDMARDs in tropical settings are incompletely defined. Methods: We retrospectively reviewed all patients with rheumatoid arthritis receiving b/tsDMARDs between October 2012 and October 2021, at Cairns Hospital in tropical Australia. The incidence, aetiology, and clinical course of serious infections (those requiring admission to hospital or parenteral antibiotics) were determined. Results: 310 patients had 1468 patient years of b/tsDMARD therapy during the study period; 74/310 (24%) had 147 serious infections translating to an overall risk of 10.0 episodes of serious infection per 100 patient years. The respiratory tract (50/147, 34%) and skin (37/147, 25%) were the most frequently affected sites. A pathogen was identified in 59/147 (40%) episodes and was most commonly Staphylococcus aureus (24/147, 16%). Only 2/147 (1%) were confirmed “tropical infections”: 1 case of Burkholderia pseudomallei and 1 case of mixed B. pseudomallei and community-acquired Acinetobacter baumannii infection. Overall, 13/147 (9%) episodes of serious infection required Intensive Care Unit admission (0.9 per 100-patient years of b/tsDMARD therapy) and 4/147 (3%) died from their infection (0.3 per 100-patient years of b/tsDMARD therapy). The burden of comorbidity and co-administration of prednisone were the strongest predictors of death or a requirement for ICU admission. Conclusions: The risk of serious infection in patients taking b/tsDMARDs in tropical Australia is higher than in temperate settings, but this is not explained by an increased incidence of traditional tropical pathogens

The epidemiology and clinical features of rickettsial diseases in North Queensland, Australia: implications for patient identification and management

Background: Rickettsial infections are a common cause of hospitalization in tropical settings, although early diagnosis is challenging in the rural locations where these infections are usually seen. Methods: This retrospective, clinical audit of microbiologically-confirmed cases of scrub typhus or spotted fever group (SFG) rickettsial infection between 1997 and 2016 was performed a tertiary referral hospital in tropical Australia. Clinical, laboratory and radiological findings at presentation were correlated with the patients’ subsequent clinical course. Results: There were 135 locally-acquired cases (95 scrub typhus, 37 SFG, 3 undifferentiated). There were nine hospitalizations during the first 5 years of the study period and 81 in the last 5 years (p for trend = 0.003). Eighteen (13%) of the 135 cases required ICU admission, all of whom were adults. A greater proportion of patients with SFG infection required ICU support (8/37 (22%) compared with 10/95 (11%) scrub typhus cases), although this difference did not reach statistical significance (p = 0.10). Three (8%) of the 37 patients with SFG infection had severe disease (1 died, 2 developed permanent disability) versus 0/95 scrub typhus patients (p = 0.02). Adults with a high admission qSOFA score (≥2) had an odds ratio (OR) of 19 (95% CI:4.8–74.5) for subsequent ICU admission (p<0.001); adults with a high NEWS2 score (≥7) had an OR of 14.3 (95% CI:4.5–45.32) for ICU admission (p<0.001). A patient’s respiratory rate at presentation had strong prognostic utility: if an adult had an admission respiratory rate <22 breaths/minute, the negative predictive value for subsequent ICU admission was 95% (95% CI 88–99). Conclusions: In the well-resourced Australian health system outcomes are excellent, but the local burden of rickettsial disease appears to be increasing and the clinical phenotype of SFG infections may be more severe than previously believed. Simple, clinical assessment on admission has prognostic utility and may be used to guide management

A decentralised, multidisciplinary model of care facilitates treatment of hepatitis C in regional Australia

Objectives: Direct-acting antiviral (DAA) therapy for hepatitis C virus (HCV) has excellent cure rates and minimal side effects. Despite the high burden of disease, strategies to ultimately eradicate HCV are being developed. However, the delivery of care in regional settings is challenging and the efficacy of decentralised models of care is incompletely defined. Methods: A prospective cohort study of patients whose treatment was initiated or supervised by Cairns Hospital, a tertiary hospital which provides services to a culturally diverse population across a 380,748 km2 area in regional Australia. Patients` demographics, clinical features, DAA regimens and outcomes were recorded and correlated with their ensuing clinical course. Results: Over 22 months, 734 patients were prescribed DAA therapy for HCV. No patients were prescribed interferon. Sofosbuvir/ledipasvir (n=371, 50.5%) and sofosbuvir/daclatasvir (n=287, 39.1%) were the most commonly prescribed regimens. No patients ceased treatment due to adverse effects. There were 612/734 (83.4%) patients with complete results, with 575 (94%) cured. At the end of the study period, there were 50 (6.8%) patients lost to follow-up and 72 (9.8%) awaiting SVR12 testing. The presence of cirrhosis (n=147/612, 24.1%) did not impact significantly on SVR12 rates, this being achieved in 136/147 (92.5%) cirrhotic patients versus 440/465 (94.6%) in non-cirrhotic patients (p=0.34). Treatment-experienced patients (95/612, 18.3%) were more likely to be non-responders than treatment-naive patients (10/95 (10.5%) versus 26/517 (5%), p=0.04). Strategies to facilitate treatment included a dedicated clinical nurse consultant, education to primary health care providers, specialist outreach clinics to regional communities and shared care with general practitioners. SVR12 rates were similar amongst gastroenterologists (283/306, 92.5%), general practitioners (152/161, 94.4%), sexual health physicians (104/106, 98.1%) and other prescribers (37/39, 94.9%). Conclusions: This study confirms that decentralised, multidisciplinary models of care can provide HCV treatment in regional and remote settings with excellent outcomes

The Incidence of Infection Complicating Snakebites in Tropical Australia: Implications for Clinical Management and Antimicrobial Prophylaxis

Objective. To define the incidence of infection following snakebite in tropical Australia and the resulting implications for the routine prescription of prophylactic antibiotics. Methods. A retrospective study of all individuals presenting to Cairns Hospital, a tertiary referral hospital in tropical Australia, after a snakebite between December 2013 and October 2020. Results. There were 732 hospitalisations, 720 (98.4%) patients presented within 8 hours of the snakebite, and 29/732 (4.0%) were envenomated. Envenomated patients were more likely to receive empirical antibiotics than nonenvenomated patients (8/29 (27.6%) versus 14/703 (2.0%), p &lt; 0.001 ), although this was frequently as a bundle of care for critically ill individuals. Superficial skin infection was diagnosed by clinicians in 6/732 (0.8%) patients during their hospitalisation; infection was diagnosed more commonly in envenomated than in nonenvenomated patients (3/29 (10.3%) versus 3/703 (0.4%), p = 0.001 ). All 3 envenomated individuals diagnosed with infection were believed to have taipan (genus Oxyuranus) bites. Five (83%) of the six patients diagnosed with infection had received empirical antibiotics at presentation; only 1/710 (0.1%) patients who received no antibiotics developed a (superficial) infection. Conclusion. Infection is a very uncommon complication of snakebite in tropical Australia. Individuals bitten by snakes in tropical Australia should not routinely receive antibiotic prophylaxis

Public health response to an outbreak of meningococcal B disease in a secondary school in Far North Queensland.

This article describes the public health response to an outbreak of meningococcal B disease, linked to a secondary school in Far North Queensland. Tropical Public Health Services in Cairns were notified of three cases of meningococcal disease in the same week in May 2022. The cases occurred in individuals who all attended, or worked in, the same secondary school. All cases were serogroup B and shared the same molecular genotype. The public health response included prompt provision of information, distribution of clearance antibiotics and two doses of MenB-4C vaccine to the entire staff and student population. Antibiotic coverage and vaccination coverage were achieved in 99% and 85% of the student population respectively. Following the intervention, no further cases were detected in the region during the subsequent nine months

A Compliant Robotic Leg Based on Fibre Jamming

Humans possess a remarkable ability to react to unpredictable perturbations through immediate mechanical responses, which harness the visco-elastic properties of muscles to maintain balance. Inspired by this behaviour, we propose a novel design of a robotic leg utilising fibre jammed structures as passive compliant mechanisms to achieve variable joint stiffness and damping. We developed multi-material fibre jammed tendons with tunable mechanical properties, which can be 3D printed in one-go without need for assembly. Through extensive numerical simulations and experimentation, we demonstrate the usefulness of these tendons for shock absorbance and maintaining joint stability. We investigate how they could be used effectively in a multi-joint robotic leg by evaluating the relative contribution of each tendon to the overall stiffness of the leg. Further, we showcase the potential of these jammed structures for legged locomotion, highlighting how morphological properties of the tendons can be used to enhance stability in robotic legs.Comment: 20 pages, 15 figures, IEEE Transactions on Robotic

Increased recognition of Q fever aortitis as a chronic manifestation of Q fever in tropical North Queensland, Australia

Aortitis is a life-threatening, manifestation of chronic Q fever. We report a series of 5 patients with Q fever aortitis who have presented to our hospital in tropical Australia since 2019. All diagnoses were confirmed with polymerase chain reaction (PCR) testing of aortic tissue. Only one had a previous diagnosis of acute Q fever, and none had classical high-risk exposures that might increase clinical suspicion for the infection. All patients underwent surgery: one died and 3 had significant complications. Q fever aortitis may be underdiagnosed; clinicians should consider testing for Coxiella burnetii in people with aortic pathology in endemic areas