Transmission Dynamics Of Cholera Research Articles

Analysis of the effect of vaccination, efficient surveillance and treatment on the transmission dynamics of cholera

Analysis of the effect of vaccination, efficient surveillance and treatment on the transmission dynamics of cholera

Mathematical Modeling of Cholera Mitigation Incorporating Handwashing

Cholera is a bacterial infection caused by Vibrio cholerae. This bacterium produces a toxin that leads to severe diarrhea and dehydration. Cholera is often associated with areas with poor sanitation, limited access to clean water and overcrowded conditions. Cholera remains a significant global health concern, with outbreaks occurring frequently in areas with poor sanitation and hygiene practices. This study aims to investigate the role of handwashing in mitigating cholera. considering the key factors such as mode of transmission, incubation period, signs and symptoms, treatment measures, risk factors and the main causes of cholera. The study tends to assess the effectiveness of handwashing as a preventive measure against cholera transmission. The research addresses the critical gap in understanding the specific contribution of handwashing in preventing cholera, considering its complex transmission dynamics. The expected results of this study are an association between increased handwashing and a decrease in cholera occurrence. Results from this study will inform evidence-based strategies for disease prevention and contribute to the broader field of infectious disease prevention modeling. The study seeks to elucidate the dynamics of cholera transmission, considering the interplay between susceptible, infectious and recovered population. Analysis of the model shows that there exists a region where the model is mathematically and epidemiologically well posed because its solutions were positive and bounded. Computation of the basic reproduction number, was done using the next generation matrix approach. It was determined that when R0 < 1, cholera does not spread. Stability analysis of the cholera model showed that the disease free equilibrium is both locally and globally asymptotically stable. Ideally, this means that keeping R0 < 1 is a possible strategy for curbing the spread of the disease. Analysis of the endemic equilibrium shows its existence when R0 > 1. Furthermore, the endemic equilibrium is also locally asymptotically stable. This shows that when R0 > 1, the disease persists and spreads in the population. Numerical simulation was done using MATLAB software to show the effectiveness of handwashing on cholera mitigation.

A Metapopulation Model for Cholera with Variable Media Efficacy and Imperfect Vaccine

In this paper, a metapopulation model has been developed and analysed to describe the transmission dynamics of cholera between two communities linked by migration, in the presence of an imperfect vaccine and a varying media awareness impact. Stability analysis shows that the disease-free equilibrium is both locally and globally asymptotically stable when the vaccine reproduction number is less than unity. The endemic equilibria have also been shown to be locally asymptotically stable when the vaccine reproduction number is greater than unity. The simulation results show that with an imperfect vaccine and efficient media awareness, cholera transmission is reduced. The transmission rates have also been shown to be nonidentical in the two communities. It is therefore advisable, that health practitioners embrace the use of both vaccination and media awareness when designing and implementing community-specific cholera intervention strategies.

Mathematical modeling for the transmission dynamics of cholera with an optimal control strategy

Cholera is an acute diarrheal disease caused by Vibrio cholera, its prevalence occurs in almost all the continents of the world, annually there are about 1.3 to 4.0 million cases of cholera and 21,000 to 143,000 deaths worldwide. In this paper, we propose a deterministic model for the transmission dynamics of cholera to assess the impact of vaccines in decreasing the spread of cholera infection in Nigeria. Moreover, we develop an optimal control strategy, in which we consider personal hygiene a control strategy on infection class, with u(t) as the control function. The best values of the fitting parameters have been obtained using least square minimization to validate the model with the help of experimental data obtained from Nigeria. We perform sensitivity analysis to determine the key parameters that have impacts on the control of the spread of cholera infections in the population. In addition, the numerical simulation of the model reveals that the use of vaccines and personal hygiene will effectively control the spread of cholera infection.

Clinical surveillance systems obscure the true cholera infection burden in an endemic region

Our understanding of cholera transmission and burden largely relies on clinic-based surveillance, which can obscure trends, bias burden estimates and limit the impact of targeted cholera-prevention measures. Serological surveillance provides a complementary approach to monitoring infections, although the link between serologically derived infections and medically attended disease incidence—shaped by immunological, behavioral and clinical factors—remains poorly understood. We unravel this cascade in a cholera-endemic Bangladeshi community by integrating clinic-based surveillance, healthcare-seeking and longitudinal serological data through statistical modeling. Combining the serological trajectories with a reconstructed incidence timeline of symptomatic cholera, we estimated an annual Vibrio cholerae O1 infection incidence rate of 535 per 1,000 population (95% credible interval 514–556), with incidence increasing by age group. Clinic-based surveillance alone underestimated the number of infections and reported cases were not consistently correlated with infection timing. Of the infections, 4 in 3,280 resulted in symptoms, only 1 of which was reported through the surveillance system. These results impart insights into cholera transmission dynamics and burden in the epicenter of the seventh cholera pandemic, where >50% of our study population had an annual V. cholerae O1 infection, and emphasize the potential for a biased view of disease burden and infection risk when depending solely on clinical surveillance data.

On the existence and numerical simulation of Cholera epidemic model

Abstract A model describing the transmission dynamics of cholera is considered in this article. The concerned model is investigated under the Caputo-Fabrizio fractal fractional derivative. The objective of this article is to study theoretical and numerical results for the model under our consideration. Classical fixed point approach is used to obtain sufficient conditions for the existence of solution to the proposed model. Adam’s Bashforth numerical method is utilized for the numerical interpretation of the suggested model. The considered technique is a powerful mathematical tool, that provides a numerical solution for the concerned problem. To discuss the transmission dynamics of the considered model, several graphical presentations are given.

Notional Spread of Cholera in Haiti Following a Natural Disaster: Considerations for Military and Disaster Relief Personnel.

Cholera remains a significant public health threat for many countries, and the severity largely varies by the population and local conditions that drive disease spread, especially in endemic areas prone to natural disasters and flooding. Epidemiological models can provide useful information to military planners for understanding disease spread within populations and the effectiveness of response options for preventing the transmission among deployed and stationed personnel. This study demonstrates the use of epidemiological modeling to understand the dynamics of cholera transmission to inform emergency planning and military preparedness in areas with highly communicable diseases. Areas with higher probability for a potential cholera outbreak in Haiti followed by a natural disaster were identified. The hotspots were then used to seed an extended compartmental model, EpiGrid, to simulate notional spread scenarios of cholera originating in three distinct areas in Haiti. Disease parameters were derived from the 2010 cholera outbreak in Haiti, and disease spread was simulated over a 12-week period under uncontrolled and controlled spread. For each model location, scenarios of mitigated (intervention with 30% transmission reduction via international aid) and unmitigated (without intervention) are simulated. The results depict the geographical spread and estimate the cumulative cholera infection for each notional scenario over the course of 3 months. Disease transmission differs considerably across origin site with an outbreak originating in the department of Nippes spanning the largest geographic area and resulting in the largest number of cumulative cases after 12 weeks under unmitigated (79,518 cases) and mitigated (35,667 cases) spread scenarios. We modeled the notional re-emergence and spread of cholera following the August 2021 earthquake in Haiti while in the midst of the global COVID-19 pandemic. This information can help guide military and emergency response decision-making during an infectious disease outbreak and considerations for protecting military personnel in the midst of a humanitarian response. Military planners should consider the use of epidemiological models to assess the health risk posed to deployed and stationed personnel in high-risk areas.

Theoretical assessment of the impact of awareness programs on cholera transmission dynamic

Abstract In this paper, we propose and analyse a mathematical model of the transmission dynamics of cholera incorporating awareness programs to study the impact of socio-media and education on cholera outbreaks. These programs induce behavioural changes in the population, which divide the susceptible class into two subclasses, aware individuals and unaware individuals. We first provide a basic study of the model. We compute the Disease-Free Equilibrium (DFE) and derive the basic reproduction number R 0 0 ${\mathcal{R}}_{0}^{0}$ that determines the extinction and the persistence of the disease. We show that there exists a threshold parameter ξ such that when R 0 0 ≤ ξ < 1 ${\mathcal{R}}_{0}^{0}\le \xi < 1$ , the DFE is globally asymptotically stable, but when ξ ≤ R 0 0 < 1 $\xi \le {\mathcal{R}}_{0}^{0}< 1$ , the model exhibits the phenomenon of backward bifurcation on a feasible region. The model exhibits one endemic equilibrium locally stable when R 0 0 > 1 ${\mathcal{R}}_{0}^{0} > 1$ and in that condition the DFE is unstable. Various cases for awareness proportions are performed using the critical awareness rate in order to measure the effect of awareness programs on the infected individuals over time. The results we obtained show that the higher implementation of strategies combining awareness programs and therapeutic treatments increase the efficacy of control measures. The numerical simulations of the model are used to illustrate analytical results and give more precision on critical values on the controls actions.

Stability Analysis and Optimal Control of a Fractional Cholera Epidemic Model

In this paper, a fractional model for the transmission dynamics of cholera was developed. In invariant regions of the model, solutions were generated. Disease-free and endemic equilibrium points were obtained. The basic reproduction number was evaluated, and the sensitivity analysis was performed. Under the support of Pontryagin’s maximum principle, the fractional order optimal control was obtained. Furthermore, an optimal strategy was discussed, which minimized the total number of infected individuals and the costs associated with control. Treatment, vaccination, and awareness programs were regarded as three means to reduce the number of infected. Finally, numerical simulations and cost-effectiveness analysis were presented to show the result that the best strategy was the combination of treatment and awareness programs.

Application of a New Generalized Fractional Derivative and Rank of Control Measures on Cholera Transmission Dynamics

In this study, the mathematical model of the cholera epidemic is formulated and analyzed to show the impact of Vibrio cholerae in reserved freshwater. Moreover, the results obtained from applying the new fractional derivative method show that, as the order of the fractional derivative increases, cholera-preventing behaviors also increase. Also, the finding of our study shows that the dynamics of Vibrio cholerae can be controlled if continuous treatment is applied in reserved freshwater used for drinking purposes so that the intrinsic growth rate of Vibrio cholerae in water is less than the natural death of Vibrio cholerae. We have applied the stability theory of differential equations and proved that the disease-free equilibrium is asymptotically stable if R 0 < 1 , and the intrinsic growth rate of the Vibrio cholerae bacterium population is less than its natural death rate. The center manifold theory is applied to show the existence of forward bifurcation at the point R 0 = 1 and the local stability of endemic equilibrium if R 0 > 1 . Furthermore, the performed numerical simulation results show that, as the rank of control measures applied increases from no control, weak control, and strong control measures, the recovered individuals are 55.02, 67.47, and 674.7, respectively. Numerical simulations are plotted using MATLAB software package.

A partially diffusive cholera model based on a general second-order differential operator

We propose a new mathematical model for cholera transmission dynamics using a system of reaction-convection-diffusion equations. The model differs from previously published partial differential equations (PDEs) based cholera models in that the diffusion and convection processes are only incorporated into the bacterial dynamics, which are described by a general second-order differential operator. This feature allows us to perform a careful study on the movement and dispersal of the pathogenic bacteria in a heterogeneous aquatic environment and its impact on cholera transmission among human hosts. We rigorously analyze the well-posedness and stability of this partially diffusive system, and establish threshold results characterizing cholera transmission dynamics.

MODELING CHOLERA TRANSMISSION UNDER DISEASE CONTROL MEASURES

We present a new mathematical model to investigate the transmission dynamics of cholera under disease control measures that include education programs and water sanitation. The model incorporates the impact of education programs into the disease transmission rates and that of water sanitation into the environmental pathogen dynamics. We conduct a detailed analysis to the autonomous system of the model and establish the local and global stabilities of its equilibria that characterize the threshold dynamics of cholera. We then perform an optimal control study on the general model with time-dependent controls and explore effective approaches to implement the education programs and water sanitation while balancing their costs. Our analysis and simulation highlight the complex interaction among the direct and indirect transmission pathways of the disease, the intrinsic growth of the environmental pathogen and the impact of multiple control measures, and their roles in collectively shaping the transmission dynamics of cholera.

Analysis of Cholera Epidemic Controlling Using Mathematical Modeling

The purpose of this study is to see whether it is possible to eradicate the disease theoretically using mathematical modeling with the aid of numerical simulation when disease occurs in a population by implementing adequate preventive measures. For this, we consider a mathematical model for the transmission dynamics of cholera and its preventive measure as one cohort of individuals, namely, a protected cohort in addition to susceptible, infected, and recovered cohorts of individuals including the concentration ofVibrio choleraein the contaminated aquatic reservoir with small modifications. We calculate the basic reproduction number,ℛ0, and investigate the existence and stability of equilibria. The model possessed forward bifurcation. Moreover, we compute the sensitivity indices of each parameter in relating toℛ0of the model. Numerical simulations are carried out to validate our theoretical results. The result indicates that the disease dies out in areas with adequate preventive measures and widespread and kills more people in areas with the inadequate preventive measures.

Modeling and analyzing cholera transmission dynamics with vaccination age

A new mathematical model is formulated to investigate the transmission dynamics of cholera under vaccination, with a focus on the impact of vaccination age. The basic reproduction number is derived and proved to be a sharp control threshold determining whether or not the infection is persistent. We conduct a rigorous analysis on the local and global stability properties of the equilibria in system. Meanwhile, we compare the results to those of the simplified model based on ordinary differential equations where the effects of vaccination age are not incorporated. Numerical simulation results verify our analytical findings.

The Role of Control Measures and the Environment in the Transmission Dynamics of Cholera

Cholera is an infectious intestinal disease which occurs as a result of poor sanitation and lack of basic education in its transmission. It is characterized by profuse vomiting and severe diarrhea when an individual eats food or drinks water contaminated with the Vibrio cholerae. A dynamic mathematical model that explicitly simulates the transmission mechanism of cholera by taking into account the role of control measures and the environment in the transmission of the disease is developed. The model comprises two populations: the human population and bacteria population. The next-generation method is used to compute the basic reproduction number, R0. Both the disease-free and endemic equilibria are shown to be locally and globally stable for R0 values less than unity and unstable otherwise. Necessary conditions of the optimal control problem were analyzed using Pontryagin’s maximum principle with control measures such as educational campaign and treatment of water bodies used to optimize the objective function. Numerical values of model parameters were estimated using the nonlinear least square method. The model simulations confirm the significant role played by control measures (education and treatment of water bodies) and the bacteria in the environment in the transmission dynamics as well as reducing the spread of cholera.

Mathematical analysis and optimal control of a cholera epidemic in different human communities with individuals’ migration

We propound a deterministic, nonlinear model for the transmission dynamics of cholera in different human communities with individuals’ migration. The considered different human communities are crossed by a running water which is contaminated by the vibrio cholerae bacterium. The formulated model for each community which is an initial/boundary-value problem constituted of four parabolic partial differential equations, integrates antibiotic treatment, hydration therapy and contaminated water treatment as control mechanisms of the disease. Using semigroup theory, we prove that this model has a unique bounded positive solution. Also under a given condition, the existence of a trivial equilibrium and of a nontrivial equilibrium of each community is established and their local and global stabilities are studied. In analysis of Turing’s instability, we determine sufficient conditions allowing the formation of a spatially stationary and periodic heterogeneous pattern. Analytically the existence of a unique optimal control is established by the use of functional analysis techniques and an optimal control θ̄ is determined to eradicate the epidemic in each community. In order to confirm our theoretical results, we finish with a real-world application concerning the cholera epidemic that took place in Cameroon in 2011.

Impact of bacterial hyperinfectivity on cholera epidemics in a spatially heterogeneous environment

In this work, we develop a new modeling framework to study the impact of bacterial hyperinfectivity on cholera epidemics in a spatially heterogeneous environment. Our model is built on a reaction-advection-diffusion system to represent spatiotemporal dynamics of cholera transmission, and incorporates bacterial hyperinfectivity and spatial heterogeneity. Firstly, we define the basic reproduction number R0 and establish the global threshold dynamics based on R0. Secondly, the global attractivity of the unique endemics equilibrium is discussed when the spatial environment is homogeneous and waning cholera immunity, advection and intrinsic growth of bacteria are ignored. Thirdly, the dependence of R0 on model parameters are numerically investigated. The theoretical results are obtained for some specific cases. Our result highlights the importance of hyperinfectivity and its interplay with spatial heterogeneity. Particularly, our findings indicate ignoring hyperinfectivity may underestimate the risk of infection.

Transmission dynamics of cholera with hyperinfectious and hypoinfectious vibrios: mathematical modelling and control strategies.

Cholera is a common infectious disease caused by Vibrio cholerae, which has different infectivity. In this paper, we propose a cholera model with hyperinfectious and hypoinfectious vibrios, in which both human-to-human and environment-to-human transmissions are considered. By analyzing the characteristic equations, the local stability of disease-free and endemic equilibria is established. By using Lyapunov functionals and LaSalle's invariance principle, it is verified that the global threshold dynamics of the model can be completely determined by the basic reproduction number. Numerical simulations are carried out to illustrate the corresponding theoretical results and describe the cholera outbreak in Haiti. The study of optimal control helps us seek cost-effective solutions of time-dependent control strategies against cholera outbreaks, which shows that control strategies, such as vaccination and sanitation, should be taken at the very beginning of the outbreak and become less necessary after a certain period.

A cholera transmission model incorporating the impact of medical resources.

We propose a mathematical model for the transmission dynamics of cholera under the impact of available medical resources. The model describes the interaction between the human hosts and the pathogenic bacteria and incorporates both the environment-to-human and human-to-human transmission routes. We conduct a rigorous equilibrium analysis to the model and establish the global asymptotic stability of the disease-free equilibrium when R0 ≤ 1 and that of the endemic equilibrium when R0 > 1. As a realistic case study, we apply our model to the Yemen cholera outbreak during 2017-2018. By fitting our simulation results to the epidemic data published by the World Health Organization, we find that different levels of disease prevalence and severity are linked to different geographical regions in this country and that cholera prevention and intervention efforts should be implemented strategically with respect to these regions in Yemen.

A cholera epidemic model in a spatiotemporally heterogeneous environment

The transmission of cholera, a water- and food-borne intestinal infection, involves complex interactions among human hosts, pathogens, and the environment, and is impacted by the spatial variation and seasonal fluctuation. In this paper, we propose a new deterministic model to investigate the spatiotemporal dynamics of cholera transmission. The model employs a reaction–convection–diffusion system to represent the spatial movement of the hosts and pathogens, and incorporates time-periodic parameters to describe the seasonality of the disease transmission and bacterial growth rates. Using the theory of principle eigenvalues, we define and analyze the basic reproduction number of this model, based on which we establish the threshold type results for cholera transmission in a spatiotemporally heterogeneous environment.