The VMI is working together with the Global Polio Eradication Initiative. This work is focusing on mathematical and statistical analysis of surveillance data to address a number of questions and needs. We have been active producing risk maps for polio outbreaks in Africa that have been used in the large scale planning of supplementary immunization activities. These risk maps have been based on estimates of population immunity, population movement and the dynamics of poliovirus in endemic countries.
They identify countries newly at risk that may have been neglected based on the distribution of past outbreaks only. In 2005, monovalent oral vaccines containing serotype 1 or serotype 3 poliovirus were rapidly developed and licensed. More recently, monovalent oral vaccine against serotype 2 poliovirus and bivalent vaccine containing both serotypes 1 and 3 were developed and licensed. Bivalent vaccine was introduced in a number of countries in late 2009 and in 2010 use began on a massive scale. In work funded by the VMI, we plan to examine the effectiveness of these vaccines in producing various types of immunity against the different poliovirus serotypes in Nigeria. We will examine the impact of immunity on wild-type poliovirus transmission in this country and use our analyses to help identify the optimal mix of vaccines to achieve the strategic goals of the Global Polio Eradication Initiative.
A working group has been created to coordinate efforts on polio modeling and data access with the goal of maximizing the impact and efficiency of polio eradication endgame strategies.