By Peter Loftus A new analysis from Israel found that maximum protection from Pfizer Inc. and BioNTech SE's Covid-19 vaccine kicked in at least two weeks after people received the second dose, and it held up even against a more transmissible variant. The Israeli analysis of real-world use of the vaccine, released Thursday, also showed that the shot was highly effective at preventing infections that don't cause symptoms, a sign that it could be helping to limit spread of the virus. And the data indicated two doses were more protective than one. The shot's performance in Israel, which has vaccinated more of its population per capita than any other country, suggests the kind of impact that inoculations could have.