A model of cholera transmission with hyperinfectivity and its optimal vaccination control

2017 ◽  
Vol 10 (06) ◽  
pp. 1750084 ◽  
Author(s):  
Chairat Modnak
Keyword(s):  
Optimal Control Theory ◽  
Control Measure ◽  
Cost Effective ◽  
Control Measures ◽  
Equilibrium Analysis ◽  
Time Dependent ◽  
Effective Control ◽  
Health Control ◽  
Vaccination Strategies ◽  
Constant Control

The use of cholera vaccines has been increasingly recognized as an effective control measure in cholera endemic countries. Also, the disease transmissions are getting more complicated and thus comprehensive strategies to implement public health control measures are worthwhile to be investigated. In this paper, we aim to better understand the effects of HI states of vibrios from the environment and from human contacts that cause cholera outbreaks. We also present and analyze our cholera mathematical model with vaccine incorporated. Equilibrium analysis is conducted in the case with constant control for both epidemic and endemic dynamics. Optimal control theory is applied to seek cost-effective solutions of time-dependent vaccination strategies against cholera outbreaks. Our results show that using vaccination during cholera outbreaks at the very beginning of the onset can reduce the number of infections significantly.

Enterprise Digital Twin

2020 ◽  
pp. 68-89
Author(s):  
Souvik Barat
Keyword(s):  
Control Measure ◽  
Dynamic Environment ◽  
Cost Effective ◽  
Control Measures ◽  
Effective Control ◽  
Digital Twin ◽  
The Core ◽  
Specific Objective ◽  
Effective Manner ◽  
Predictive Analyses

Enterprises constantly aim to maximise their objectives while operating in a competitive and dynamic environment. This necessitates an enterprise to be efficient, adaptive, and amenable for transformation. However, understanding a complex enterprise and identifying effective control measure, adaptation choice, or transformation option to realise specific objective is not a trivial task. The digital twin that imitates the real enterprise provides an environment to conduct the necessary interrogative and predictive analyses to evaluate various control measures, adaptation choices, and transformation options in a safe and cost-effective manner without compromising the analysis precision. This chapter reflects on the core concept of the digital twin, evaluates the state-of-the-art modelling and analysis technologies, and presents a pragmatic approach to develop high-fidelity digital twin for large complex enterprises.

scholarly journals Community Knowledge and Attitudes about the Transmission of Dengue Haemorrhagic Fever and Its Relationship to Prevention Behaviour in Palembang, South Sumatra, Indonesia

2021 ◽  
Vol 9 (E) ◽  
pp. 1534-1543
Author(s):  
Minarti Minarti ◽  
Chairil Anwar ◽  
Irfannuddin Irfannuddin ◽  
Chandra Irsan
Keyword(s):  
Vector Control ◽  
Control Measure ◽  
Public Awareness ◽  
Cost Effective ◽  
Hemorrhagic Fever ◽  
Control Measures ◽  
Good Knowledge ◽  
Effective Control ◽  
Control Practice ◽  
Prevention Behavior

BACKGROUND: PSN 3 M Plus is a long-running program in Indonesia for the prevention and control of dengue hemorrhagic fever (DHF). AIM: This study aimed to determine the knowledge, behavior, attitudes, and beliefs of the community toward PSN 3 M Plus in preventing and controlling the spread of DHF. METHODS: A cluster random sampling method was used to recruit 200 respondents in endemic areas and 100 respondents in sporadic locations of Indonesia from August 2020 to February 2021. The respondents were interviewed directly by interviewers and the relationships between demographics and characteristics with the practice of PSN 3M Plus prevention behavior on the incidence of DHF were analyzed. RESULTS: Most respondents had good knowledge regarding the cause of DHF. Although respondents recognized and understood the dangers of and how to control DHF, most did not follow PSN 3 M Plus and believed that fogging was the most effective control measure. There was a significant relationship between the characteristics of the respondents in terms of education, occupation, and attitude on vector control practice. CONCLUSION: Although community environmental modifications can be a cost-effective approach to reduce the incidence of DHF, there is a need to raise public awareness regarding preventive vector control measures as good knowledge does not guarantee good compliance with PSN 3M Plus recommendations.

Characterizing the effectiveness of COVID-19 mitigation measures: A data-centric approach (Preprint)

2020 ◽  
Author(s):  
Lukman Olagoke ◽  
Ahmet E. Topcu
Keyword(s):  
Control Measure ◽  
Control Measures ◽  
World Health ◽  
Mitigation Measures ◽  
Effective Control ◽  
The World ◽  
Decision Making Processes ◽  
And Performance ◽  
Health Organization ◽  
The Impact

BACKGROUND COVID-19 represents a serious threat to both national health and economic systems. To curb this pandemic, the World Health Organization (WHO) issued a series of COVID-19 public safety guidelines. Different countries around the world initiated different measures in line with the WHO guidelines to mitigate and investigate the spread of COVID-19 in their territories. OBJECTIVE The aim of this paper is to quantitatively evaluate the effectiveness of these control measures using a data-centric approach. METHODS We begin with a simple text analysis of coronavirus-related articles and show that reports on similar outbreaks in the past strongly proposed similar control measures. This reaffirms the fact that these control measures are in order. Subsequently, we propose a simple performance statistic that quantifies general performance and performance under the different measures that were initiated. A density based clustering of based on performance statistic was carried out to group countries based on performance. RESULTS The performance statistic helps evaluate quantitatively the impact of COVID-19 control measures. Countries tend show variability in performance under different control measures. The performance statistic has negative correlation with cases of death which is a useful characteristics for COVID-19 control measure performance analysis. A web-based time-line visualization that enables comparison of performances and cases across continents and subregions is presented. CONCLUSIONS The performance metric is relevant for the analysis of the impact of COVID-19 control measures. This can help caregivers and policymakers identify effective control measures and reduce cases of death due to COVID-19. The interactive web visualizer provides easily digested and quick feedback to augment decision-making processes in the COVID-19 response measures evaluation. CLINICALTRIAL Not Applicable

Water safety plans for small systems: a model for applying HACCP concepts for cost-effective monitoring in developing countries

2003 ◽  
Vol 47 (3) ◽  
pp. 215-220 ◽  
Author(s):  
G. Howard
Keyword(s):  
Risk Factors ◽  
Water Quality ◽  
Cost Effective ◽  
Control Measures ◽  
Effective Control ◽  
Performance Limits ◽  
Water Safety ◽  
Small Systems ◽  
Water Safety Plans ◽  
Contamination Events

The development of water safety plans (WSPs) for small systems should be based on a thorough understanding of the relationships between risk factors and contamination events. This can be achieved through the use of well-designed assessments of water quality that provide better evidence to support the identification of control measures, performance limits, monitoring parameters and verification procedures. Training of community operators is critical to the success of the WSP and the understanding gained from the assessments provides a sound basis for addressing these needs. The WSP approach provides for more effective control of water quality and the use of targeted assessments is cost-effective in improving the design of WSPs.

scholarly journals Development of a Sanitation Safety Plan for improving the sanitation system in peri-urban areas of Iringa, Tanzania

2017 ◽  
Vol 7 (2) ◽  
pp. 340-348 ◽  
Author(s):  
M. Domini ◽  
G. Langergraber ◽  
L. Rondi ◽  
S. Sorlini ◽  
S. Maswaga
Keyword(s):  
Urban Areas ◽  
Cost Effective ◽  
Control Measures ◽  
Effective Control ◽  
Safety Plan ◽  
First Results ◽  
Assessment Matrix ◽  
Planning Methodology ◽  
The Given

The Sanitation Safety Planning methodology is implemented within a cooperation project in Iringa, Tanzania. The study presents the methodology and its adaptation and use for the given context, in order to assess risks and to support stakeholders in improving the current sanitation system and validate the design of an improved one. First results of the application of the methodology, obtained in one of the four peri-urban wards of Iringa, demonstrated its efficacy and utility in prioritising risks and identifying cost-effective control measures. Risks were assessed by the use of a semi-quantitative approach, and a simplified risk assessment matrix was developed for the case study. A sensitivity analysis was carried out in order to evaluate criteria for prioritising control measures to be selected for the development of an achievable improvement plan.

scholarly journals China’s effective control and other countries’ uncharted challenge against COVID-19: an epidemiological and modelling study

2020 ◽  
Author(s):  
Lingling Zheng ◽  
Qin Kang ◽  
Weiyao Liao ◽  
Xiujuan Chen ◽  
Shuai Huang ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Reproduction Number ◽  
Case Reports ◽  
Epidemiological Data ◽  
Control Measures ◽  
Time Dependent ◽  
Effective Control ◽  
List Type ◽  
Global Epidemic ◽  
Serial Interval

AbstractBackgroundOn the present trajectory, COVID is inevitably becoming a global epidemic, leading to concerns regarding the pandemic potential in China and other countries.ObjectiveIn this study, we use the time-dependent reproduction number (Rt) to comprise the COVID transmissibility across different countries.MethodsWe used data from Jan 20, 2019, to Feb 29, 2020, on the number of newly confirmed cases, obtained from the reports published by the CDC, to infer the incidence of infectious over time. A two-step procedure was used to estimate the Rt. The first step used data on known index-secondary cases pairs, from publicly available case reports, to estimate the serial interval distribution. The second step estimated the Rt jointly from the incidence data and the information data in the first step. Rt was then used to simulate the epidemics across all major cities in China and typical countries worldwide.ResultsBased on a total of 126 index-secondary cases pairs from 4 international regions, we estimated that the serial interval for SARS-2-CoV was 4.18 (IQR 1.92 – 6.65) days. Domestically, Rt of China, Hubei province, Wuhan had fallen below 1.0 on 9 Feb, 10 Feb and 13 Feb (Rt were 0.99±0.02, 0.99±0.02 and 0.96±0.02), respectively. Internationally, as of 26 Feb, statistically significant periods of COVID spread (Rt >1) were identified for most regions, except for Singapore (Rt was 0.92±0.17).ConclusionsThe epidemic in China has been well controlled, but the worldwide pandemic has not been well controlled. Worldwide preparedness and vulnerability against COVID-19 should be regarded with more care.What is already known on this subject?The basic reproduction number (R0) and the-time-dependent reproduction number (Rt) are two important indicators of infectious disease transmission. In addition, Rt as a derivative of R0 could be used to assess the epidemiological development of the disease and effectiveness of control measures. Most current researches used data from earlier periods in Wuhan and refer to the epidemiological features of SARS, which are possibly biased. Meanwhile, there are fewer studies discussed the Rt of COVID-19. Current clinical and epidemiological data are insufficient to help us understand the full view of the potential transmission of this disease.What this study adds?We use up-to-data observation of the serial interval and cases arising from local transmission to calculate the Rt in different outbreak level area and every province in China as well as five-top sever outbreak countries and other overseas. By comparing the Rt, we discussed the situation of outbreak around the world.

scholarly journals Global stability analysis and control of leptospirosis

2016 ◽  
Vol 14 (1) ◽  
pp. 567-585 ◽  
Author(s):  
Kazeem Oare Okosun ◽  
M. Mukamuri ◽  
Daniel Oluwole Makinde
Keyword(s):  
Cost Effectiveness ◽  
Basic Reproduction Number ◽  
Reproduction Number ◽  
Cost Effective ◽  
Control Measures ◽  
Basic Reproductive Number ◽  
Control Parameters ◽  
Constant Control ◽  
Preventive Vaccination ◽  
The Basic Reproduction Number

AbstractThe aim of this paper is to investigate the effectiveness and cost-effectiveness of leptospirosis control measures, preventive vaccination and treatment of infective humans that may curtail the disease transmission. For this, a mathematical model for the transmission dynamics of the disease that includes preventive, vaccination, treatment of infective vectors and humans control measures are considered. Firstly, the constant control parameters’ case is analyzed, also calculate the basic reproduction number and investigate the existence and stability of equilibria. The threshold condition for disease-free equilibrium is found to be locally asymptotically stable and can only be achieved when the basic reproduction number is less than unity. The model is found to exhibit the existence of multiple endemic equilibria. Furthermore, to assess the relative impact of each of the constant control parameters measures the sensitivity index of the basic reproductive number to the model’s parameters are calculated. In the time-dependent constant control case, Pontryagin’s Maximum Principle is used to derive necessary conditions for the optimal control of the disease. The cost-effectiveness analysis is carried out by first of all using ANOVA to check on the mean costs. Then followed by Incremental Cost-Effectiveness Ratio (ICER) for all the possible combinations of the disease control measures. Our results revealed that the most cost-effective strategy for the control of leptospirosis is the combination of the vaccination and treatment of infective livestocks. Though the combinations of all control measures is also effective, however, this strategy is not cost-effective and so too costly. Therefore, more efforts from policy makers on vaccination and treatment of infectives livestocks regime would go a long way to combat the disease epidemic.

Ecology of the maize stalk borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae)

1987 ◽  
Vol 77 (2) ◽  
pp. 255-269 ◽  
Author(s):  
J. B. J. Van Rensburg ◽  
M. C. Walters ◽  
J. H. Giliomee
Keyword(s):  
Plant Development ◽  
Busseola Fusca ◽  
Cost Effective ◽  
Control Measures ◽  
Effective Control ◽  
Planting Dates ◽  
Plant Parts ◽  
New Information ◽  
Repeated Sampling ◽  
Definite Pattern

AbstractNew information on the intraseasonal progression of larval infestations of Busseola fusca (Fuller) in South Africa was obtained through repeated sampling in maize plantings of different planting dates over various seasons. Due to the occurrence of distinct periods of moth flight, variation in planting date had a marked influence on levels of larval infestation. Also, plants were found to be most attractive as sites for oviposition between three and five weeks after emergence, resulting in a definite pattern in the time distribution of different larval instars in different plant parts. In the pre-tassel stage of plant development, most larvae occurred in localized groups within the whorls, reaching maximum numbers eight weeks after plant emergence. The emergence of the tassel forced some larvae to migrate to adjacent plants, resulting in an increase of internally damaged plants without an increase in larval numbers. It is shown that scouting for eggs over a limited period of plant development can lead to better timing of spray applications and thus to more cost-effective control measures.

scholarly journals Predicting spread and effective control measures for African swine fever– should we blame the boars?

2019 ◽  
Author(s):  
Rachel A. Taylor ◽  
Tomasz Podgórski ◽  
Robin R. L. Simons ◽  
Sophie Ip ◽  
Paul Gale ◽  
...  
Keyword(s):  
At Risk ◽  
Wild Boar ◽  
Control Strategies ◽  
Control Measure ◽  
African Swine Fever ◽  
Control Measures ◽  
Effective Control ◽  
Risk Of Infection ◽  
Long Distance ◽  
Baltic Countries

SummaryAfrican swine fever (ASF) has been causing multiple outbreaks in Russia, Poland and the Baltic countries in recent years and is currently spreading westwards throughout Europe and eastwards into China, with cases occurring in wild boar and domestic pigs. Curtailing further spread of ASF requires full understanding of the transmission pathways of the disease. Wild boars have been implicated as a potential reservoir for the disease and one of the main modes of transmission within Europe. We developed a spatially explicit model to estimate the risk of infection with ASF in boar and pigs due to the natural movement of wild boar that is applicable across the whole of Europe. We demonstrate the model by using it to predict the probability that early cases of ASF in Poland were caused by wild boar dispersion. The risk of infection in 2015 is computed due to wild boar cases in Poland in 2014, compared against the reported cases in 2015 and then the procedure is repeated for 2015-2016. We find that long- and medium-distance spread of ASF (i.e. >30km) is very unlikely to have occurred due to boar dispersal, due in part to the generally short distances boar will travel (<20km on average). We also predict what the relative success of different control strategies would have been in 2015, if they were implemented in 2014. Results suggest that hunting of boar reduces the number of new cases, but a larger region is at risk of ASF compared to no control measure. Alternatively, introducing boar-proof fencing reduces the size of the region at risk in 2015, but not the total number of cases. Overall, our model suggests wild boar movement is only responsible for local transmission of disease, thus other pathways are more dominant in medium and long distance spread of the disease.

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