Change in polio vaccination strategy leads to unexpected outbreaks
In a significant health shift, the 2016 change to the oral polio vaccine, aimed at eradicating the disease, inadvertently contributed to new outbreaks. This modified vaccine strategy, called “the switch,” removed a strain of the poliovirus that was causing outbreaks, in an effort to make it easier to control the disease. Tracing the origins of the virus that led to the recent paralysis of a child in Gaza, the first such case in the region in more than two decades, is a complex process. Genetic tracing suggests the virus likely originated in Nigeria, then appeared in Chad in 2019. From…