Effectiveness of Dengue leaky vaccine: a modelling approach

Dengue, an endemic disease transmitted by the Aedes aegypti mosquito, affects millions of people annually across various regions worldwide, as reported by the World Health Organization (WHO). The control of dengue transmission is challenging due to the complex dynamics of its vector. However, the advent of vaccines presents a significant opportunity to alter the epidemiological landscape. In this context, the use of mathematical models to assess the impact of interventions in epidemics becomes an essential tool for understanding how vaccine introduction can influence the current scenario. This study employs stochastic modeling to analyze different scenarios in a partially vaccinated population, considering the leaky nature of the vaccine and its association with a reduction in the transmission rate. We derive the master equation for a vector-borne disease model, as in (de Souza, 2013), including the presence of vaccinated individuals and calculate the basic reproduction number using one-site and pair-site mean-field approximations. By calculating vaccine effectiveness using the method presented in (Shim, 2012), we performed simulations of epidemic scenarios to evaluate various control measures. Our results highlight the role of transmission rate, vaccine efficacy, vector control, and the proportion of vaccinated individuals in the epidemic's dynamic process and the vaccine's effectiveness in population protection. Furthermore, we demonstrate non-linear behaviors that can be compared to vaccination programs implemented for recently adopted vaccines, such as Qdenga and Butantan-DV, in Brazil.

DE SOUZA, David R. et al. Stochastic dynamics of dengue epidemics. Physical Review E—Statistical, Nonlinear, and Soft Matter Physics, v. 87, n. 1, p. 012709, 2013.

SHIM, Eunha; GALVANI, Alison P. Distinguishing vaccine efficacy and effectiveness. Vaccine, v. 30, n. 47, p. 6700-6705, 2012.