A Simulation Study on Spread of Disease and Control Measures in Closed Population Using ABM

An infectious disease can cause a detrimental effect on national security. A group such as the military called a “closed population”, which is a subset of the general population but has many distinct characteristics, must survive even in the event of a pandemic. Hence, it requires its own distinct solution during a pandemic. In this study, we investigate a simulation analysis for implementing an agent-based model that reflects the characteristics of agents and the environment in a closed population and finds effective control measures for making the closed population functional in the course of disease spreading.

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Survey and control of small mammal populations on two hardwood plantations in southern Ontario

The Forestry Chronicle ◽

10.5558/tfc50181-5 ◽

1974 ◽

Vol 50 (5) ◽

pp. 181-185 ◽

Cited By ~ 3

Author(s):

Andrew Radvanyi

Keyword(s):

Small Mammal ◽

Late Summer ◽

Control Measures ◽

Effective Control ◽

Southern Ontario ◽

Live Trapping ◽

Surrounding Areas ◽

And Control ◽

Rodent Populations ◽

Ingredient Cost

Live trapping and tagging methods were employed to assess small mammal populations within two hardwood plantations in southern Ontario. Excessive girdling damage in past years to young planted trees necessitated an evaluation of rodent populations and development of effective control measures. The application of an anticoagulant rodenticide to oat groats bait broadcast over the study area at an ingredient cost of approximately three dollars per acre virtually wiped out the small mammals. Reinvasion from surrounding areas was, however, fairly rapid, particularly during late summer. Further research on longer term control measures using poisoned bait feeder stations is recommended.

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Effective control measures limited measles outbreak after extensive nosocomial exposures in January-February 2008 in Gothenburg, Sweden

Eurosurveillance ◽

10.2807/ese.13.30.18937-en ◽

2008 ◽

Vol 13 (30) ◽

Author(s):

P Follin ◽

L Dotevall ◽

M Jertborn ◽

Y Khalid ◽

J Å Liljeqvist ◽

...

Keyword(s):

Vaccination Coverage ◽

Control Measures ◽

Effective Control ◽

Imported Case ◽

Measles Outbreak ◽

Measles Outbreaks ◽

Rubella Vaccination ◽

And Control

In January-February 2008, one imported case of measles initiated a series of exposures with around 380 nosocomial secondary contacts. Susceptible individuals were traced early and control measures were initiated that managed to limit the consequences considerably. Only four secondary cases were identified by the end of March. This minor outbreak illustrates the importance and efficiency of early control measures as well as the fact that the risk of measles outbreaks still exists in a country that has high measles, mumps, rubella vaccination coverage among children.

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Yellow Nutsedge (Cyperus esculentus) Competition and Control in Corn (Zea mays)

Weed Science ◽

10.1017/s0043174500043435 ◽

1979 ◽

Vol 27 (1) ◽

pp. 32-37 ◽

Cited By ~ 38

Author(s):

E. W. Stoller ◽

L. M. Wax ◽

F. W. Slife

Keyword(s):

Zea Mays ◽

Control Measures ◽

Effective Control ◽

Yield Reduction ◽

Cyperus Esculentus ◽

Yellow Nutsedge ◽

Effective Combination ◽

Percentage Yield ◽

Hand Weeding ◽

And Control

Competition of yellow nutsedge (Cyperus esculentusL.) with corn (Zea maysL.) was evaluated in the field at various yellow nutsedge densities over a 3-yr period. A relationship between yellow nutsedge density (shoots/m2) and percentage yield reduction revealed an 8% yield reduction for every 100 shoots/m2. Two 3-yr studies were conducted to determine the most effective combination of preplant-incorporated, postemergence, or postemergence-directed treatments for yellow nutsedge control in corn. The preplant incorporated treatments were alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide], EPTC (S-ethyl dipropylthiocarbamate), or nothing; postemergence treatments were bentazon [3-isopropyl-1H-2,1,3-benzothiadiazin-(4) 3H-one 2,2-dioxide], two cultivations, or nothing; and the postemergence-directed treatments were ametryn [2-(ethylamino)-4-(isopropylamino)-6-(methylthio)-s-triazine] or nothing. One preplant-incorporated treatment of EPTC or alachlor prevented yield reductions from yellow nutsedge competition. When no control was practiced, yields were reduced 17% in a moderate yellow nutsedge infestation (initially infested with 300 tubers/m2) and 41% in a heavy infestation (initially infested with 1200 tubers/m2). Yields were reduced 7 to 8% in the moderate infestation when no preplant-incorporated treatments were used regardless of whether postemergence or postemergence-directed treatments were also used. After 1 yr, all control measures resulted in less tuber density than no control measures, but all control treatments had essentially similar tuber densities. After the second year, several herbicide treatments were as effective as hand weeding in reducing tuber density. At least 2 yr of effective control treatments were required to reduce tubers to 20% of the original density, and 3 yr of treatment to reduce the density to 15% of the original density. No combination of treatments, including hand weeding, eliminated tubers after 3 yr.

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UN peacekeeping operations: when can unlawful acts committed by peacekeeping forces be attributed to the UN?

Legal Studies ◽

10.1111/j.1748-121x.2011.00225.x ◽

2012 ◽

Vol 32 (2) ◽

pp. 282-301 ◽

Cited By ~ 3

Author(s):

Russell Buchan

Keyword(s):

Legal Framework ◽

Effective Control ◽

Un Peacekeeping ◽

The Icj ◽

Peacekeeping Forces ◽

Peacekeeping Missions ◽

Unlawful Conduct ◽

International Law Commission ◽

And Control ◽

The Military

UN peacekeeping missions operate under the authority of the UN. However, the military personnel that constitute a UN peacekeeping mission remain organs of the states from which they are contributed. Thus, whether unlawful acts committed by peacekeepers can be attributed to the UN is dependent upon whether the peacekeeping force can be regarded as being under the direction and control of the UN. This is a question of fact. According to the ICJ and the International Law Commission, unlawful acts committed by peacekeeping forces will be attributed to the UN only where the UN exercised ‘effective control’ over the commission of the unlawful act. In contrast, the ECtHR has consistently propounded a very different test, asserting that unlawful acts will be attributed to the UN only where the UN retained ‘ultimate authority and control’ over the peacekeeping mission. I argue, however, that neither of these tests provides a suitable legal framework for determining attribution of unlawful conduct in the context of UN peacekeeping missions. After outlining the deficiencies of these tests, I submit that a more suitable approach to determining attribution would be based upon the overall control test as outlined by the ICTY in Tadić.

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Modelling, Simulations and Analysis of the First and Second COVID-19 Epidemics in Beijing

10.1101/2021.04.02.21254821 ◽

2021 ◽

Author(s):

Lequan Min

Keyword(s):

Numerical Simulations ◽

Prevention And Control ◽

Control Strategies ◽

Equation Model ◽

Control Measures ◽

Disease Spreading ◽

Prevention And Control Measures ◽

Asymptomatic Individuals ◽

Reported Data ◽

And Control

AbstractTo date, over 130 million people on infected with COVID-19. It causes more 2.8 millions deaths. This paper introduces a symptomatic-asymptomatic-recoverer-dead differential equation model (SARDDE). It gives the conditions of the asymptotical stability on the disease-free equilibrium of SARDDE. It proposes the necessary conditions of disease spreading for the SARDDE. Based on the reported data of the first and the second COVID-19 epidemics in Beijing and simulations, it determines the parameters of SARDDE, respectively. Numerical simulations of SARDDE describe well the outcomes of current symptomatic and asymptomatic individuals, recovered symptomatic and asymptomatic individuals, and died individuals, respectively. The numerical simulations suggest that both symptomatic and asymptomatic individuals cause lesser asymptomatic spread than symptomatic spread; blocking rate of about 90% cannot prevent the spread of the COVID19 epidemic in Beijing; the strict prevention and control strategies implemented by Beijing government is not only very effective but also completely necessary. The numerical simulations suggest also that using the data from the beginning to the day after about two weeks at the turning point can estimate well or approximately the following outcomes of the two COVID-19 academics, respectively. It is expected that the research can provide better understanding, explaining, and dominating for epidemic spreads, prevention and control measures.

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Mathematical modeling and comparative analysis of the Ebola epidemic reveal effective control measures

10.21203/rs.2.14493/v1 ◽

2019 ◽

Author(s):

Junlong Li ◽

Caiping Song ◽

Jingya Yang ◽

Jingmin Zheng ◽

Lina Zhou ◽

...

Keyword(s):

Mathematical Modeling ◽

Comparative Analysis ◽

Sierra Leone ◽

Development Process ◽

Ebola Virus ◽

Virus Disease ◽

Control Measures ◽

Effective Control ◽

Epidemic Outbreak ◽

And Control

Abstract The Ebola virus disease (EVD) is a highly contagious disease which is caused by the Ebola virus . Various measures were used to prevent and control the spread of EVD. The aim of this study was to find out the most critical measures to prevent and control the spread of EVD. Both mathematical modeling and comparative analysis were used to explore the development process of EVD outbreak in Guinea, Liberia and Sierra Leone. The results of comparative analysis showed quarantined individuals before infection (R 2 = 0.848, ε = 1.012), safe burial teams (R 2 = 0.772, ε = 0.385), and the Ebola treatment units (ETU) bed (R 2 = 0.690, ε = 0.432) could significantly influence the incidence of EVD which were consistent with the results of mathematical modeling. These findings indicted that a timely and effective quarantine played a significant role in preventing and controlling the spread of EVD, and the findings would help us prevent and control the epidemic outbreak of new infectious disease in the future.

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A REVIEW OF DAMPING-OFF OF DOUGLAS FIR SEEDLINGS IN BRITISH COLUMBIA

The Forestry Chronicle ◽

10.5558/tfc30407-4 ◽

1954 ◽

Vol 30 (4) ◽

pp. 407-410 ◽

Cited By ~ 1

Author(s):

P. J. Salisbury

Keyword(s):

British Columbia ◽

Control Measures ◽

Effective Control ◽

Damping Off ◽

Natural Control ◽

Cover Soil ◽

Low Degree ◽

Nursery Practices ◽

Forest Nurseries ◽

And Control

Except in new nurseries, damping-off in British Columbia forest nurseries has remained below serious levels. Modification of nursery practices has served to reduce losses. The use of a suitable, sandy cover soil has been effective. Lowered fertility of the soil, though a problem in itself, appears to decrease incidence of damping-off. The acidity of the soil in coast nurseries may have afforded some natural control of the disease. From investigations on the control of damping-off, there appears to be promise in the use of peat as a planting medium for stratified seed, and, based on experiments with unstratified seed, in the application of fungicides to cover soil. In view of the present low degree of the disease, there would appear to be an opportunity for research directed to the biology and control of fungi known to be capable of causing sudden outbreaks, without the urgent need of finding immediately effective control measures.

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MYCOPLASMA INFECTIONS IN CHILDHOOD

PEDIATRICS ◽

10.1542/peds.40.4.669 ◽

1967 ◽

Vol 40 (4) ◽

pp. 669-684

Author(s):

Wallace A. Clyde ◽

Floyd W. Denny

Keyword(s):

Wide Spectrum ◽

Carrier State ◽

Control Measures ◽

Effective Control ◽

Clinical Aspects ◽

Relative Role ◽

Course Of Disease ◽

Tract Disease ◽

Epidemiologic Features

Mycoplasmas compose a ubiquitous group of minute microorganisms which include saprophytes, commensals, and pathogens. Of the seven species which have been isolated from man, only Mycoplasma pneumoniae has clearly established pathogenicity. Research continues to seek other possible disease relationships, since there are various animal diseases caused by mycoplasmas which have counterparts among human illnesses of unknown cause. M. pneumoniae can be associated with a wide spectrum of respiratory tract disease, including bullous myringitis, pharyngitis, tracheobronchitis, pneumonia, and subclinical infections. These illnesses are generally mild and occur most frequently between ages 5 and 19 years in slowly progressive epidemics. The clinical aspects of the disease are indistinguishable from virus-associated syndromes, and epidemiologic features are often more suggestive of the diagnosis. Techniques for M. pneumoniae cultivation and serodiagnosis are now adaptable for use in clinical laboratories. Non-specific diagnostic tests, especially cold hemagglutination, have distinctly limited usefulness in pediatrics. M. pneumoniae is sensitive to the tetracycline drugs and erythromycin; administration of these antibiotics shortens the clinical course of disease but may not be effective for prophylaxis or elimination of the carrier state. For these reasons, vaccines could provide more effective control and are being developed; however, greater experience concerning the relative role of M. pneumoniae among other respiratory disease agents is required before the need for control measures in the general population can be assessed.

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Epidemiological investigation of the Central Scotland outbreak of Escherichia coli O157 infection, November to December 1996

Epidemiology and Infection ◽

10.1017/s0950268801005520 ◽

2001 ◽

Vol 126 (3) ◽

pp. 335-341 ◽

Cited By ~ 49

Author(s):

J. M. COWDEN ◽

S. AHMED ◽

M. DONAGHY ◽

A. RILEY

Keyword(s):

Escherichia Coli ◽

Bloody Diarrhoea ◽

Control Measures ◽

Effective Control ◽

Escherichia Coli O157 ◽

Epidemiological Investigation ◽

Outbreak Strain ◽

Source Of Infection ◽

And Control

On Friday, 22 November 1996, the microbiologist at a hospital in Lanarkshire, Scotland, identified presumptive Escherichia coli O157 in faecal specimens submitted by three patients with bloody diarrhoea, and confirmed its presence in one. Over the next 6 h, 12 more potential cases were identified. Investigations first indicated then confirmed a single food premises as the source of infection. Effective control measures were applied promptly. The outbreak was declared over on 20 January 1997, by which time 512 cases had been identified, and infection with the outbreak strain confirmed in 279. Twenty deaths occurred in cases during the outbreak and there were two more in cases during 1997. Seventeen of these deaths resulted from the outbreak. This paper describes the outbreak's epidemiological investigation, referring to other investigations, and control measures, where appropriate.

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Effects of medical resource capacities and intensities of public mitigation measures on outcomes of COVID-19 outbreaks

BMC Public Health ◽

10.1186/s12889-021-10657-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Xia Wang ◽

Qian Li ◽

Xiaodan Sun ◽

Sha He ◽

Fan Xia ◽

...

Keyword(s):

Prevention And Control ◽

Control Strategies ◽

Control Measures ◽

Mitigation Measures ◽

Effective Control ◽

Medical Resource ◽

Key Factors ◽

Medical Resources ◽

Detection Rates ◽

And Control

Abstract Background The COVID-19 pandemic is complex and is developing in different ways according to the country involved. Methods To identify the key parameters or processes that have the greatest effects on the pandemic and reveal the different progressions of epidemics in different countries, we quantified enhanced control measures and the dynamics of the production and provision of medical resources. We then nested these within a COVID-19 epidemic transmission model, which is parameterized by multi-source data. We obtained rate functions related to the intensity of mitigation measures, the effective reproduction numbers and the timings and durations of runs on medical resources, given differing control measures implemented in various countries. Results Increased detection rates may induce runs on medical resources and prolong their durations, depending on resource availability. Nevertheless, improving the detection rate can effectively and rapidly reduce the mortality rate, even after runs on medical resources. Combinations of multiple prevention and control strategies and timely improvement of abilities to supplement medical resources are key to effective control of the COVID-19 epidemic. A 50% reduction in comprehensive control measures would have led to the cumulative numbers of confirmed cases and deaths exceeding 590,000 and 60,000, respectively, by 27 March 2020 in mainland China. Conclusions Multiple data sources and cross validation of a COVID-19 epidemic model, coupled with a medical resource logistic model, revealed the key factors that affect epidemic progressions and their outbreak patterns in different countries. These key factors are the type of emergency medical response to avoid runs on medical resources, especially improved detection rates, the ability to promote public health measures, and the synergistic effects of combinations of multiple prevention and control strategies. The proposed model can assist health authorities to predict when they will be most in need of hospital beds and equipment such as ventilators, personal protection equipment, drugs, and staff.

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