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Malaysia continues to record high number of dengue cases despite efforts to reduce dengue transmission by vector control. Hence, safe and efficient vaccine is essential to effective dengue control. To vaccinate a significant proportion of the population, the vaccine must be affordable. This paper aims to develop a pricing model to establish an appropriate threshold price of vaccine for Malaysia, following World Health Organization (WHO) guidelines. This pricing model involves a dengue transmission model based on the SIR concept for estimating the economic burden of dengue. Dengue can reduce the effective life expectancy technically known as the disability-adjusted life-years (DALY). Conversely, effective vaccine can improve DALY and therefore can impart economic value. Simulations suggested that vaccine can reduce dengue cases by 79 %, decrease economic burden by 55 % and lower DALY by 54 %. This can be achieved if vaccine efficacy is eighty percent and if this vaccine is applied to everyone aged between 9 to 45 years before the onset of disease. Based on the price model analysis, we recommend a highly- cost-effective and affordable vaccine price threshold of USD 5 per dose for Malaysia. [ABSTRACT FROM AUTHOR]

Epidemiology modelling provides an understanding of the underlying mechanisms that influence the spread of dengue disease. The most common mathematical models used are the compartment models abbreviated by ASI-SIR, ASEI-SIR and ASEI-SEIR. This paper starts with a discussion of these common models, followed by the derivation of the basic reproduction number (Ro) of each model. The value of Ro in ASI-SIR model is higher than that in ASEI-SIR and ASEI-SEIR models due to the exclusion of exposed adult mosquito in ASI-SIR model. Further, sensitivity analysis on Ro indicates that natural mortality and biting rate of adult mosquito have significant effects on dengue transmission dynamics. Next, an in-house mathematical model named MOSSEIR is developed, based upon the ASEI-SEIR compartment model, in which both mosquito and human populations are considered. The mosquito population is divided into four compartments consisting of aquatic mosquito, susceptible, exposed and infected adult mosquito; while the human population is classified into four compartments comprising susceptible, exposed, infected and recovered human. MOSSEIR is then used to replicate the number of dengue cases in 2010 for Shah Alam, a capital city of Selangor with high incidence of dengue fever. Finally, effectiveness of control strategies, including mosquito breeding sites control, fogging and vaccination, are evaluated for Shah Alam. Simulation results indicate that these three control strategies can significantly reduce dengue transmission, in theory. In reality, the effectiveness of traditional control methods such as elimination of mosquito breeding sites and fogging is below expectation due to non-compliance. Therefore, the adoption of a safe, effective and affordable vaccine remains the best prospect for controlling dengue. [ABSTRACT FROM AUTHOR]