Africa’s emerging polio problem

At the end of 2019, Science connected the dots on a range of polio incidents across 12 countries last year that left 196 children paralyzed.

The culprit was not wild poliovirus — the long-time public health bogeyman — but polio type 2 that emerged from previous vaccinations. The vaccine uses weakened strains of the virus, which can change over time to behave more like the naturally occurring version of the virus. → Read the rest “Africa’s emerging polio problem”