• EPIDEMICS
• EPIDEMIOLOGY
• Molecular Epidemiology

There is nothing to be gained by saying that the Global Polio Eradication Initiative (GPEI) has made tremendous progress since its commitment, in 1988, to eradicate polio.1 There has been a reduction in the incidence of poliomyelitis by more than 99% and the number of countries that have never interrupted wild poliovirus (WPV) transmission has reduced from an estimated 125 countries to 3 countries (Afghanistan, Nigeria and Pakistan).1 In 1999, the GPEI announced the eradication of WPV type 2,2 and the most recent case due to WPV type 3 was reported after November 2012 in Nigeria. However, WPV type 1 and circulating vaccine-derived polioviruses (cVDPVs) continue to spread in endemic countries and be imported to previously polio-free countries.3 Although global polio eradication has been delayed by 15 years past the original target date set for the year 2000, the eradication is considered feasible by the GPEI based on the success achieved so far.4 However, the GPEI is faced with a chain of challenges to free the world from the last 1% of WPV and VDPV transmission. The main difficulties in stemming polio transmission in the three endemic countries are peculiar; successful eradication depends on an in-depth understanding of specific factors hindering polio vaccination campaigns in these countries. Lack of trust, political instability, violence and militancy are the main factors that threaten polio eradication efforts in all three countries.5 Some areas of these countries have yet to consider polio a priority amidst other health problems such as malnutrition, lack of potable water supply and poverty, as well as a host of childhood killer diseases (eg, malaria, pneumonia and diarrhoea). …