Oxford, AstraZeneca Vaccine Data Show Effectiveness With Spread-Out Doses

University of Oxford researchers said spacing doses of its Covid-19 vaccine apart by as long as three months improved effectiveness, though some independent researchers said the trial had limits.University of Oxford researchers said spacing doses of its Covid-19 vaccine apart by as long as three months improved effectiveness, though some independent researchers said the trial had limits.Read MorePAIDWSJ.com: US Business