A ‘truly historic’ study could free the world of polio, the World Health Organization claims.
Researchers have discovered that using both types of polio vaccine boosts immunity.
Published in the journal Science, the research shows that in children who have already received multiple doses of the oral polio vaccine (OPV), a shot of inactivated polio vaccine (IPV) is better at boosting immunity than another OPV.
By using more of the IPV in mass vaccination campaigns, the researchers believe the world can “accelerate eradication of the virus”.
Polio is spread through contaminated faeces. The disease can cause paralysis and death.
In 1988 there were 350,000 cases of polio in more than 125 countries. Since then the number of global cases has fallen by more than 99%, however it still affects countries such as Nigeria, Pakistan and Afghanistan.
Dr Bruce Aylward, the World Health Organization assistant director general for polio, said: "The results of this study are truly historic in the context of global polio eradication.
"This study has revolutionised our understanding of inactivated polio vaccine and how to use it in the global eradication effort to ensure children receive the best and quickest protection possible from this disease."