141,434 research outputs found

    Efficiency of prompt quarantine measures on a susceptible-infected-removed model in networks

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    This study focuses on investigating the manner in which a prompt quarantine measure suppresses epidemics in networks. A simple and ideal quarantine measure is considered in which an individual is detected with a probability immediately after it becomes infected and the detected one and its neighbors are promptly isolated. The efficiency of this quarantine in suppressing a susceptible-infected-removed (SIR) model is tested in random graphs and uncorrelated scale-free networks. Monte Carlo simulations are used to show that the prompt quarantine measure outperforms random and acquaintance preventive vaccination schemes in terms of reducing the number of infected individuals. The epidemic threshold for the SIR model is analytically derived under the quarantine measure, and the theoretical findings indicate that prompt executions of quarantines are highly effective in containing epidemics. Even if infected individuals are detected with a very low probability, the SIR model under a prompt quarantine measure has finite epidemic thresholds in fat-tailed scale-free networks in which an infected individual can always cause an outbreak of a finite relative size without any measure. The numerical simulations also demonstrate that the present quarantine measure is effective in suppressing epidemics in real networks.Comment: 10 pages, 7 figure

    Quarantine Risk Analysis

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    Australia’s quarantine policy is based on the concept of manageable risk, which is underpinned by quarantine risk analysis, which this article examines with particular reference to recommendations of the 1996 Australian Quarantine Review. Quarantine risk assessment addresses disease concerns associated with any particular proposed import and may also require detailed examination of possible economic and environmental effects. The degree of quantification varies, and more quantitative approaches may be either deterministic or stochastic. Assessments consider both the probability of an event occurring and its consequences, including the direct economic effect of any introduction of an exotic disease.International Relations/Trade,

    Viking planetary quarantine procedures and implementation

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    Some of the techniques and methodology that were used on Viking to implement planetary quarantine requirements are reported. Special attention was given to techniques and approaches used to implement sterilization of the Viking probe. Quarantine procedures for unmanned planetary missions and procedures for microbiological contamination of space hardware are included. A probability of contamination of the biological instruments onboard by terrestrial organisms was examined

    Orbiting quarantine facility. The Antaeus report

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    A mission plan for the Orbiting Quarantine Facility (OQF) is presented. Coverage includes system overview, quarantine and protocol, the laboratory, support systems, cost analysis and possible additional uses of the OQF

    Analysis of CDC social control measures using an agent-based simulation of an influenza epidemic in a city

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    Background: the transmission of infectious disease amongst the human population is a complex process which requires advanced, often individual-based, models to capture the space-time details observed in reality.Methods: an Individual Space-Time Activity-based Model (ISTAM) was applied to simulate the effectiveness of non-pharmaceutical control measures including: (1) refraining from social activities, (2) school closure and (3) household quarantine, for a hypothetical influenza outbreak in an urban area.Results: amongst the set of control measures tested, refraining from social activities with various compliance levels was relatively ineffective. Household quarantine was very effective, especially for the peak number of cases and total number of cases, with large differences between compliance levels. Household quarantine resulted in a decrease in the peak number of cases from more than 300 to around 158 for a 100% compliance level, a decrease of about 48.7%. The delay in the outbreak peak was about 3 to 17 days. The total number of cases decreased to a range of 3635-5403, that is, 63.7%-94.7% of the baseline value.When coupling control measures, household quarantine together with school closure was the most effective strategy. The resulting space-time distribution of infection in different classes of activity bundles (AB) suggests that the epidemic outbreak is strengthened amongst children and then spread to adults. By sensitivity analysis, this study demonstrated that earlier implementation of control measures leads to greater efficacy. Also, for infectious diseases with larger basic reproduction number, the effectiveness of non-pharmaceutical measures was shown to be limited.Conclusions: simulated results showed that household quarantine was the most effective control measure, while school closure and household quarantine implemented together achieved the greatest benefit. Agent-based models should be applied in the future to evaluate the efficacy of control measures for a range of disease outbreaks in a range of settings given sufficient information about the given case and knowledge about the transmission processes at a fine scal

    The Trade and Welfare Impact of Australian Quarantine Policies: The Case of Pigmeat

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    Abstract: We analyze the trade and welfare impact of quarantine measures imposed by Australiaon imports of pigmeat. In particular, we account for changes to Australia’s pigmeat quarantinepolicy over time including those changes related to the recent resolution of a WTO disputebetween Australia and the European Union. Using a random utility model, and applying it tocorner solutions in import decisions, tariff equivalents (by major trading partner) are estimatedfor the different pigmeat quarantine regimes implemented by Australia during the period 1988-2009. The welfare impact on consumers, producers, and foreign exporters is computed using apartial equilibrium model calibrated on the econometric estimates. The quarantine regimes havea strong effect on trade and welfare with a tariff equivalent above 113% of average real worldprices over the period analyzed.pigmeat; pork; australia; non-tariff measure; NTM; quarantine; import ban; trade
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