I always love spotlighting polio eradication. Along with Guinea worm, it is one of the few candidates to follow smallpox to the eternal (or so we all hope) halls of eradicated diseases. While the eradication effort has suffered its setbacks in recent years, public health workers have persisted, steadily marching onward. And frankly, there has been so much hand-wringing in global health in recent weeks that it is important to occasionally remember that there are still wins we can, and should, celebrate.
What makes this success possible in addition to trackable is the global network of polio surveillance systems, which was featured in CDC’s MMWR at the beginning of April:
The primary means of detecting poliovirus transmission is surveillance for acute flaccid paralysis (AFP) among children aged [less than] 15 years, combined with collection and testing of stool specimens from persons with AFP for detection of WPV and vaccine-derived polioviruses (VDPVs)…in WHO-accredited laboratories within the Global Polio Laboratory Network. AFP surveillance is supplemented by environmental surveillance for polioviruses in sewage from selected locations. Genomic sequencing of the VP1-coding region of isolated polioviruses enables mapping transmission by time and place, assessment of potential gaps in surveillance, and identification of the emergence of VDPVs. For public health nerds like me, all of MMWR’s polio reports can be found here.
Basically, a combination of syndromic and environmental surveillance allows public health systems to track polio where it pops up, and genetic sequencing helps to trace how the virus got to where it did to shed light on transmission patterns and find gaps in surveillance.
The WHO followed with two YouTube videos featuring the global polio surveillance system and polio vaccination, which is what will make eradication possible:
This is all pretty straightforward stuff – we all know generally that surveillance systems do, in fact, work when their infrastructure is properly supported and that children should be vaccinated against polio. But it’s important to not lose focus on our successes and global health progress, even when it is simple, straightforward, and sometimes slow.