Browsing by Author "Ainea, Neterindwa"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Modeling infectiology and optimal control of HCV disease in a community with inflow of infected immigrants
    (University of Dar es Salaam, 2016) Ainea, Neterindwa
    In this thesis, a model that describes the dynamics of the spread of Hepatitis C Virus (HCV) disease in the presence of infective immigration is developed and analysed. The epidemic threshold and existence of equilibrium are investigated. The model undergoes backward bifurcation so that the condition (basic reproduction number) is less than unity, is necessary but not sufficient for the eradication of HCV in a community with inflow of infective immigrants. Optimal control theory is applied to study the level of effort needed to control the spread of HCV disease using three controls namely; education, health care (i.e. hygiene), immunization (i.e. vaccination), screening and treatment. Results show that in the absence of control measures, infective immigrants have a decisive impact on the dynamics of the transmission of infection. It is further observed that the effectively use of optimal screening of immigrants together with other control strategies has a significant impact in reducing the spread of the disease in the community compared to the case with no control. Incremental Cost-Effectiveness Ratio (ICER) shows that use of optimal education, health care and immunization is the best cost effective control strategy although it requires 100% application throughout the intervention period. The major conclusion from the study is therefore that this study shows that the perspective of effectively use of optimal screening of immigrants together with education, health care, immunization and treatment should be enforced.
  • Thumbnail Image
    Item
    Modelling the effect of treatment and infected immigrants on the spread of hepatitis c virus disease with acute and chronic stages
    (University of Dar es Salaam, 2011) Ainea, Neterindwa
    A mathematical model on the effect of Treatment and Infected Immigrants on the spread of Hepatitis C Virus disease with Acute and Chronic stages has been studied. This study intends to improve the work by Cai and Li (2007), by including the aspect of infective immigrants and treatment in a homogeneous population. Effective Reproduction Number (Re) computed by using next generation operator approach. The stability of the system has been analyzed for the existence of the disease free and endemic equilibrium points, and it has been shown that the disease free equilibrium point is locally asymptotically stable when Re < 1 otherwise the disease is endemic. The model undergoes forward bifurcation, and consequently occurs at Re=1. If Re >1, the endemic solution exists and is a global attractor while the disease free solution is a saddle point. Numerical results show that disease become more endemic due to the presence of Infected immigrants in the community. It is also indicated that in the presence of treatment, the rate of infected immigrants (acute and chronic) decreases and consequently the treated infected individuals decreases continuously. From the analysis. it may be hypothesized that preventive measures, through reducing rates of transmission of HCV are therefore necessary to the conununity. The national health care to HCV should seek to ensure that all people at risk or that have been at risk in the past, have access to and are supported in the use of HCV education and prevention regardless of their social and economic status.