Israeli health authorities have embarked on a country wide campaign to administer polio vaccine to all children nine years of age and younger. The rabbonim, including HaRav Chaim Kanievsky and HaRav Yitzchok Zilberstein, who has particular expertise in medical issues, have endorsed the campaign.
Every child born in Israel up to today receives a polio vaccine made of dead polio virus. Up until nine years ago, every child also received a vaccine with a live but very weak virus. At that time, in view of the guidelines of the World Health Organization, it was decided that there was no need to administer the weakened virus. The polio virus had not been seen in Israel for years.
Recently the polio virus has been detected, mainly in the sewage of Bedouin settlements in the south of Israel. A few carriers of the virus have been found, but no one has become sick with the virus. Health authorities decided that the prudent thing to do is to give all those children who never got the weakened virus a dose, since that would eradicate even the carriers.
Hundreds of thousands of children have received the virus so far, and the plan is to give it to virtually all of them.