An international team of scientists is set to develop a wholly artificial vaccine that addresses some of the shortcomings in existing anti-polio vaccines.
Polio is very close to being eradicated worldwide, with only a few hundred cases, in a few specific regions, being reported annually. The World Health Organization and the Bill & Melinda Gates Foundation are providing a $674,000 grant to a group of researchers in the US and UK who will participate in the program.
While only a few hundred cases of polio were reported in 2014, mainly from Pakistan, the last mile towards eradicating the re hundreds of thousands of cases worldwide, just 350 were reported last year, and most of those were in Pakistan. But the last mile is proving to be frustrating.
One reason is because the existing oral vaccine uses a weakened version of the virus as its stimulus to provoke a response and protection in the patient. And in just a few particular individuals, this can set up an infection in the gut that then enables a reactivated virus to pass out of the body and spread to other, unvaccinated people.
The idea of the synthetic vaccine is that it contains no genetic material – it is virus free and so has no way of replicating and transmission from this route is blocked. The scientists stress that a synthetic approach is just part of the strategy required to totally eliminate polio, and they warn that vaccination would have to continue for some years beyond the last recorded case to make sure it had no chance of re-establishing itself.