A study recently published in PLOS Pathogens shows scientists from the National Institute for Biological Standards and Control in the United Kingdom are working to create a new generation of vaccine strains that will be efficient and not result in illness if they are intentionally or accidentally released.
This development is in light of fears that creating and stockpiling vaccines that have live viruses could be harmful. Some are worried that the live virus may be accidentally or intentionally released, repopulating throughout the world. This is especially important because polio elimination is closer than it has ever been before.
There are many kinds of polio vaccines available for the public. Unfortunately, none of them are top in safety. Live attenuated vaccine strains are weakened. These strains are genetically mutated so they do not cause any illness. Sometimes these strains can result in virulent, or more dangerous, virus.
There are many ways that the strains continue to live inside people who have compromised immune systems. The strains are then released through the people’s feces. This could be an important health concern in the future, which is why creating safe strains is important.
"We have developed new strains for [inactivated poliovirus vaccine] production with negligible risk to the human population should they escape,” the researchers said.
When polio is eliminated, the World Health Organization (WHO) intends to stop using active weakened strains in the vaccines. The WHO has stated the new producers of vaccines need to use an attenuated strain of polio instead of a virulent strain. This is meant to prevent any polio outbreaks after it has been eliminated.