WHO Declares End of Polio Outbreaks in Five African Countries

# WHO Declares End of Polio Outbreaks in Five African Countries ### Why in News? **WHO** confirmed that circulating vaccine-derived poliovirus type 2 outbreaks had ended in Burundi, Ghana, Guinea-Bissau, the Republic of Congo and Uganda. ### What does “vaccine-derived poliovirus” mean? - In under-immunised populations, the weakened virus used in oral polio vaccine can circulate for a long period and rarely mutate into a form capable of causing disease; this is called circulating vaccine-derived poliovirus. - **WHO** declared the outbreaks closed after assessments found transmission had been interrupted and population immunity had improved. - The result shows why high vaccination coverage and strong surveillance remain essential even after wild poliovirus transmission falls. ### Exam Connect - **Polio** → viral disease mainly affecting children - **cVDPV2** → circulating vaccine-derived poliovirus type 2 - **WHO** → headquarters Geneva