Clinics around the world are destroying an old, problematic polio vaccine in favor of a new oral one, in an unprecedented effort that has never before been attempted.
The problem with the old vaccine? It was causing polio. Oops.
The massive global eradication effort takes place within the next few weeks at thousands of sites in 155 different countries, and requires a complete destruction of every single vial of the vaccine for the worldwide plan to work.
“Health workers have been taught to destroy the old vaccine by boiling it, incinerating it, even burying it in the ground,” reports NPR.org.
The old vaccine, health experts claim, targeted a polio strain – type 2 – that has been all but wiped out since 1999. Since vaccines contain live, but weakened strains of the viruses they intend to fight, the strains often mutate and can cause polio.
“Last year,” for instance according to NPR, “the world recorded about 100 cases of polio. About 30 of them were caused by mutant strains from the old vaccine. The new vaccine also has a live virus in it, but it mutates much less often. So in the long run, it should cause about 90 percent fewer cases.”
The new vaccine only targets Type 1 and Type 3 polio strains, so it’s vital to destroy the older strain as there will no longer be a vaccine to protect against it.
“If some aren’t” completely destroyed, reports NPR, “some of that virus could leak out into the world, and we could have outbreaks of a type of polio we haven’t seen since 1999.”
UNICEF Chief of Immunization Robin Nandy says they’re preparing for that scenario to play out.
“We do expect this and we have put in place measures to detect this very quickly and respond to this,” Nandy told NPR.
One reason the old strain of polio may persist is due to confusing labels.
“Adding to the possibility of confusion, the old and new vials and boxes are almost identical. Warehouse managers are supposed to mark the old vaccine with an ‘X’ and bag it for disposal,” The New York Times writes.
One health expert told The Times he believed it would be difficult for the public to trust a new vaccine after the effort.
“This changeover is unprecedented,” former CDC associate director Dr. Walter A. Orenstein told The Times.
“This is going to be hard,” said Orenstein. “For a long time, we’ve driven people to think of vaccine as valuable. Now we’re asking them to destroy it.”
UNICEF’s Nandy says the new initiative is imperative to the overall polio eradication effort, “because if the world is ever going to wipe out polio,” NPR says, “we have to first make sure the vaccine isn’t causing it.”