Nigeria, Democratic Republic of Congo, Central African Republic, and Angola have experienced nine new cases of polio caused by the live virus in oral polio vaccines that has mutated into an infectious form, according to statistics released [November 20] by the World Health Organization. That brings the global total of these types of infections to 157 for the year, and it means that more children are paralyzed as a result of such vaccine-derived infections than illnesses caused by the wildtype virus, which has affected 107 people this year.
Other countries in Africa and Asia have also reported such vaccine-derived infections, which have the potential to spark new outbreaks.
“It’s actually crazy because we’re vaccinating now against the vaccine in most parts of the world,” Vincent Racaniello, a virologist at Columbia University, tells NPR, “not against wild polio, which is confined to Pakistan and Afghanistan.”
Starting in April 2016, public health care workers around the world have made the transition from a trivalent vaccine with types 1, 2, and 3 to a bivalent version without type 2 to prevent such vaccine-derived cases.
Read full, original post: Polio Vaccination Causes More Infections than Wild Virus