SAN FRANCISCO — A San Francisco Bay Area man in his 30s is recuperating after developing a rare blood clot in his leg within two weeks of receiving the Johnson & Johnson vaccine, As of Friday, the U.S. Centers for Disease Control and Prevention had reported the condition in 15 people, all women, after 8 million doses were administered nationally. It involves unusual clots that occur together with low levels of blood-clotting platelets. “To the best of our knowledge, this is the first male patient with VITT syndrome in the U.S. following the Johnson & Johnson vaccine on Feb. 27, 2021," UCSF said in a statement.