Domestic vaccine for polio licensed

China's top drug authority has licensed a new domestically grown vaccine to protect children from polio, and it will be introduced into the country's vaccination schedule this year, according to the China Food and Drug Administration.

Under the national vaccination program, newborns - an estimated 16 million each year - are required to get oral polio vaccine, or OPV, which, in extremely rare cases, can cause paralytic polio in a recipient because it contains a weakened but still live virus.

About one in every 1 million children who take the vaccine develop that side effect, experts said.