By Peter Loftus Deliveries of Johnson & Johnson's Covid-19 vaccine doses throughout the U.S. are expected to plunge by more than 80% next week, according to state officials and federal data, as J&J grapples with manufacturing challenges. The federal government has allocated just 700,000 doses of J&J's vaccine to U.S. states, territories and certain cities and federal agencies next week, compared with 4.9 million doses that were allocated for this week, according to information posted online by the Centers for Disease Control and Prevention. The expected sharp decrease will complicate states officials' mass vaccination plans at a time when they're counting on a greater supply of doses to help immunize the growing number of people becoming eligible.