Rabbi Doctor Menachem Haim Brayer, the deputy medical director of Me'ayanei HaYeshua Hospital in Bnei Brak, who is in charge of ethics in medicine and halacha and the sanctity of life at the hospital, has received agreement from leading authorities in halakha (Jewish law) that according to Jewish law, anyone who is not yet vaccinated against the measles virus must immediately do so.
The rabbis also ruled that someone who is not vaccinated is not only defined as a "blood spiller" because of the harm one may inflict on one's self, but because of the danger to others, since the disease spreads rapidly from one person to another. This applies not only to people who have not been vaccinated but also to those who have been vaccinated but have a weak immune system.