Infectious Diseases - Research Publications
Now showing items 1-12 of 576
A framework for scabies control
(PUBLIC LIBRARY SCIENCE, 2021-09-01)
Scabies is a neglected tropical disease (NTD) that causes a significant health burden, particularly in disadvantaged communities and where there is overcrowding. There is emerging evidence that ivermectin-based mass drug administration (MDA) can reduce the prevalence of scabies in some settings, but evidence remains limited, and there are no formal guidelines to inform control efforts. An informal World Health Organization (WHO) consultation was organized to find agreement on strategies for global control. The consultation resulted in a framework for scabies control and recommendations for mapping of disease burden, delivery of interventions, and establishing monitoring and evaluation. Key operational research priorities were identified. This framework will allow countries to set control targets for scabies as part of national NTD strategic plans and develop control strategies using MDA for high-prevalence regions and outbreak situations. As further evidence and experience are collected and strategies are refined over time, formal guidelines can be developed. The control of scabies and the reduction of the health burden of scabies and associated conditions will be vital to achieving the targets set in WHO Roadmap for NTDs for 2021 to 2030 and the Sustainable Development Goals.
Water-Borne Nanocoating for Rapid Inactivation of SARS-CoV-2 and Other Viruses
(AMER CHEMICAL SOC, 2021-09-28)
The rise in coronavirus variants has resulted in surges of the disease across the globe. The mutations in the spike protein on the surface of the virion membrane not only allow for greater transmission but also raise concerns about vaccine effectiveness. Preventing the spread of SARS-CoV-2, its variants, and other viruses from person to person via airborne or surface transmission requires effective inactivation of the virus. Here, we report a water-borne spray-on coating for the complete inactivation of viral particles and degradation of their RNA. Our nanoworms efficiently bind and, through subsequent large nanoscale conformational changes, rupture the viral membrane and subsequently bind and degrade its RNA. Our coating completely inactivated SARS-CoV-2 (VIC01) and an evolved SARS-CoV-2 variant of concern (B.1.1.7 (alpha)), influenza A, and a surrogate capsid pseudovirus expressing the influenza A virus attachment glycoprotein, hemagglutinin. The polygalactose functionality on the nanoworms targets the conserved S2 subunit on the SARS-CoV-2 virion surface spike glycoprotein for stronger binding, and the additional attachment of guanidine groups catalyze the degradation of its RNA genome. Coating surgical masks with our nanoworms resulted in complete inactivation of VIC01 and B.1.1.7, providing a powerful control measure for SARS-CoV-2 and its variants. Inactivation was further observed for the influenza A and an AAV-HA capsid pseudovirus, providing broad viral inactivation when using the nanoworm system. The technology described here represents an environmentally friendly coating with a proposed nanomechanical mechanism for inactivation of both enveloped and capsid viruses. The functional nanoworms can be easily modified to target viruses in future pandemics, and is compatible with large scale manufacturing processes.
Myocarditis Caused by Human Parechovirus in Adult
(CENTERS DISEASE CONTROL, 2017-09-01)
The infectious etiology of myocarditis often remains unidentified. We report a case of myocarditis associated with human parechovirus (HPeV) infection in an adult. HPeV is an emerging pathogen that can cause serious illness, including myocarditis, in adults. Testing for HPeV should be considered in differential diagnosis of myocarditis.
SARS-CoV-2 seroprevalence in healthcare workers in a tertiary healthcare network in Victoria, Australia
(ELSEVIER INC, 2021-08-01)
BACKGROUND: Healthcare workers (HCW) are exposed to an increased risk of COVID-19 through direct contact with patients and patient environments. We calculated the; seroprevalence of SARS-CoV-2 in HCW at Eastern Health, a tertiary healthcare network in Victoria, and assessed associations with demographics, work location and role. METHODS: A cross-sectional cohort study of HCW at Eastern Health was conducted. Serum was analysed for the presence of antibodies to SARS-CoV-2, and all participants completed; an online survey collecting information on demographics, place of work, role, and exposures; to COVID-19. Seroprevalence was calculated as the proportion participants with SARS-CoV-2; antibodies out of all tested individuals. RESULTS: The crude seroprevalence of SARS-CoV-2 antibodies in this study was 2.17% (16/736). Thirteen of the 16 (81.2%) positive cases had previously been diagnosed with COVID-19 by PCR: the seroprevalence in the group not previously diagnosed with COVID by PCR was 0.42% (3/720). Having direct contact with COVID-19 patients did not increase the likelihood of having positive serology. A prior history of symptoms consistent with COVID-19 was associated with a higher likelihood of having positive serology (OR 17.2, p = 0.006, 95%CI: 2.25-131.55). CONCLUSION: Our calculated seroprevalence of 2.17% is higher than estimated in the general Australian population, but lower than that reported in HCW internationally. The; majority of those with positive serology in our study had previously been diagnosed with COVID-19 by PCR based testing. Seropositivity was not associated with interaction with COVID-19 positive patients, highlighting effective infection prevention and control practices within the workplace.
Quantifying the mental health burden of the most severe covid-19 restrictions: A natural experiment
BACKGROUND: The COVID-19 pandemic, and the restrictions required to halt spread of the infection, are associated with increased population burden of moderate to severe symptoms of depression and anxiety. The aim was to quantify the mental health burden of the most severe COVID-19 related restrictions. METHODS: A natural experiment in which differences between Australian states and territories in the severity of restrictions for pandemic control, divided the population. People in Victoria experienced the most severe, and people in all other states and territories less severe or negligible restrictions. Data were collected in national, anonymously completed, online surveys (in April and in July / August 2020) of adults in Australia. Outcomes were, in the previous fortnight, experiencing clinically significant depressive symptoms (Patient Health Questionnaire 9 score ≥10); or symptoms of generalised anxiety (Generalised Anxiety Disorder Scale 7 score ≥10). RESULTS: In total, 23,749 eligible respondents contributed complete data. There were no differences in the population burden of mental health problems between Victoria and the other states and territories at Survey One. By Survey Two prevalence rates of clinically significant depressive (Adjusted Odds Ratio (aOR) 1.96; 95% CI 1.62; 2.37) and anxiety (aOR 1.87; 95%CI 1.53; 2.29) symptoms were substantially and significantly higher in Victoria than in other states and territories. LIMITATIONS: Online surveys are less accessible to some groups of people. The data are self-report and not diagnostic. CONCLUSIONS: The most severe COVID-19 restrictions are associated with near double the population prevalence of moderate to severe depressive and generalised anxiety symptoms.
Lopinavir-ritonavir and hydroxychloroquine for critically ill patients with COVID-19: REMAP-CAP randomized controlled trial
PURPOSE: To study the efficacy of lopinavir-ritonavir and hydroxychloroquine in critically ill patients with coronavirus disease 2019 (COVID-19). METHODS: Critically ill adults with COVID-19 were randomized to receive lopinavir-ritonavir, hydroxychloroquine, combination therapy of lopinavir-ritonavir and hydroxychloroquine or no antiviral therapy (control). The primary endpoint was an ordinal scale of organ support-free days. Analyses used a Bayesian cumulative logistic model and expressed treatment effects as an adjusted odds ratio (OR) where an OR > 1 is favorable. RESULTS: We randomized 694 patients to receive lopinavir-ritonavir (n = 255), hydroxychloroquine (n = 50), combination therapy (n = 27) or control (n = 362). The median organ support-free days among patients in lopinavir-ritonavir, hydroxychloroquine, and combination therapy groups was 4 (- 1 to 15), 0 (- 1 to 9) and-1 (- 1 to 7), respectively, compared to 6 (- 1 to 16) in the control group with in-hospital mortality of 88/249 (35%), 17/49 (35%), 13/26 (50%), respectively, compared to 106/353 (30%) in the control group. The three interventions decreased organ support-free days compared to control (OR [95% credible interval]: 0.73 [0.55, 0.99], 0.57 [0.35, 0.83] 0.41 [0.24, 0.72]), yielding posterior probabilities that reached the threshold futility (≥ 99.0%), and high probabilities of harm (98.0%, 99.9% and > 99.9%, respectively). The three interventions reduced hospital survival compared with control (OR [95% CrI]: 0.65 [0.45, 0.95], 0.56 [0.30, 0.89], and 0.36 [0.17, 0.73]), yielding high probabilities of harm (98.5% and 99.4% and 99.8%, respectively). CONCLUSION: Among critically ill patients with COVID-19, lopinavir-ritonavir, hydroxychloroquine, or combination therapy worsened outcomes compared to no antiviral therapy.
Ethnically Disparate Disease Progression and Outcomes among Acute Rheumatic Fever Patients in New Zealand, 1989-2015
(CENTERS DISEASE CONTROL & PREVENTION, 2021-07-01)
We investigated outcomes for patients born after 1983 and hospitalized with initial acute rheumatic fever (ARF) in New Zealand during 1989-2012. We linked ARF progression outcome data (recurrent hospitalization for ARF, hospitalization for rheumatic heart disease [RHD], and death from circulatory causes) for 1989-2015. Retrospective analysis identified initial RHD patients <40 years of age who were hospitalized during 2010-2015 and previously hospitalized for ARF. Most (86.4%) of the 2,182 initial ARF patients did not experience disease progression by the end of 2015. Progression probability after 26.8 years of theoretical follow-up was 24.0%; probability of death, 1.0%. Progression was more rapid and ≈2 times more likely for indigenous Māori or Pacific Islander patients. Of 435 initial RHD patients, 82.2% had not been previously hospitalized for ARF. This young cohort demonstrated low mortality rates but considerable illness, especially among underserved populations. A national patient register could help monitor, prevent, and reduce ARF progression.
Metabolic regulation of hepatitis B immunopathology by myeloid-derived suppressor cells
(NATURE PUBLISHING GROUP, 2015-06-01)
Infection with hepatitis B virus (HBV) results in disparate degrees of tissue injury: the virus can either replicate without pathological consequences or trigger immune-mediated necroinflammatory liver damage. We investigated the potential for myeloid-derived suppressor cells (MDSCs) to suppress T cell-mediated immunopathology in this setting. Granulocytic MDSCs (gMDSCs) expanded transiently in acute resolving HBV, decreasing in frequency prior to peak hepatic injury. In persistent infection, arginase-expressing gMDSCs (and circulating arginase) increased most in disease phases characterized by HBV replication without immunopathology, whilst L-arginine decreased. gMDSCs expressed liver-homing chemokine receptors and accumulated in the liver, their expansion supported by hepatic stellate cells. We provide in vitro and ex vivo evidence that gMDSCs potently inhibited T cells in a partially arginase-dependent manner. L-arginine-deprived T cells upregulated system L amino acid transporters to increase uptake of essential nutrients and attempt metabolic reprogramming. These data demonstrate the capacity of expanded arginase-expressing gMDSCs to regulate liver immunopathology in HBV infection.
COVID-19 end-of-life care: symptoms and supportive therapy use in an Australian hospital
BACKGROUND: Descriptions of symptoms and medication use at end of life in COVID-19 are limited to small cross-sectional studies, with no Australian longitudinal data. AIMS: To describe end-of-life symptoms and care needs of people dying of COVID-19. METHODS: This retrospective cohort study included consecutive admitted patients who died at a Victorian tertiary referral hospital from 1 January to 30 September directly due to COVID-19. Clinical characteristics, symptoms and use of supportive therapies, including medications and non-pharmacological interventions in the last 3 days of life were extracted. RESULTS: The cohort comprised 58 patients (median age 87 years, interquartile range (IQR) 81-90) predominantly admitted from home (n = 30), who died after a median of 11 days (IQR 6-28) in the acute medical (n = 31) or aged care (n = 27) wards of the hospital. The median Charlson Comorbidity Score was 7 (IQR 5-8). Breathlessness (n = 42), agitation (n = 36) and pain (n = 33) were the most frequent clinician-reported symptoms in the final 3 days of life, with most requiring opioids (n = 52), midazolam (n = 40), with dose escalation commonly being required. While oxygen therapy was commonly used (n = 47), few (n = 13) required an anti-secretory agent. CONCLUSIONS: This study presents one of the first and largest Australian report of the end of life and symptom experience of people dying of COVID-19. This information should help clinicians to anticipate palliative care needs of these patients, for example, recognising that higher starting doses of opioids and sedatives may help reduce prevalence and severity of breathlessness and agitation near death.
Presenting symptoms of COVID-19 and clinical outcomes in hospitalised older adults
BACKGROUND: In July 2020, a COVID-19 outbreak was recognised in the geriatric wards at a subacute campus of the Royal Melbourne Hospital affecting patients and staff. Patients were also admitted to this site after diagnosis in residential care. AIMS: To describe the early symptoms and the outcomes of COVID-19 in older adults. METHODS: Patients diagnosed with COVID-19 at the facility in July or August 2020 were identified and their medical records were examined to identify symptoms present before and after their diagnosis and to determine their outcomes. RESULTS: Overall, 106 patients were identified as having COVID-19, with median age of 84.3 years (range 41-104 years); 64 were diagnosed as hospital inpatients after a median length of stay of 49 days, 31 were transferred from residential aged care facilities with a known diagnosis and 11 were diagnosed after discharge. There were 95 patients included in an analysis of symptom type and timing onset. Overall, 61 (64.2%) were asymptomatic at the time of diagnosis of COVID-19, having been diagnosed through screening initiated on site. Of these, 88.6% developed symptoms of COVID-19 within 14 days. The most common initial symptom type was respiratory, but there was wide variation in presentation, including fever, gastrointestinal and neurological symptoms, many initially not recognised as being due to COVID-19. Of 104 patients, 32 died within 30 days of diagnosis. CONCLUSIONS: COVID-19 diagnosis is challenging due to the variance in symptoms. In the context of an outbreak, asymptomatic screening can identify affected patients early in the disease course.
Reprogrammed CRISPR-Cas13b suppresses SARS-CoV-2 replication and circumvents its mutational escape through mismatch tolerance
<h4>ABSTRACT</h4> Mutation-driven evolution of SARS coronavirus-2 (SARS-CoV-2) highlights the need for innovative approaches that simultaneously suppress viral replication and circumvent viral escape routes from host immunity and antiviral therapeutics. Here, we employed genome-wide computational prediction and singlenucleotide resolution screening to reprogram CRISPR-Cas13b against SARS-CoV-2 genomic and subgenomic RNAs. Reprogrammed Cas13b effectors targeting accessible regions of Spike and Nucleocapsid transcripts achieved >98% silencing efficiency in virus free-models. Further, optimized and multiplexed gRNAs suppressed viral replication by up to 90% in mammalian cells infected with replication-competent SARS-CoV-2. Unexpectedly, the comprehensive mutagenesis of guide-target interaction demonstrated that single-nucleotide mismatches do not impair the capacity of a potent single gRNA to simultaneously suppress ancestral and mutated SARS-CoV-2 in infected mammalian cells, including the highly infectious and globally disseminated Spike D614G mutant. The specificity, efficiency and rapid deployment properties of reprogrammed Cas13b described here provide a molecular blueprint of antiviral therapeutics to simultaneously suppress a wide range of SARS-CoV-2 mutants, and is readily adaptable to other emerging pathogenic viruses.