Nearly 300 Schools Closed

Washington

Nearly 300 schools scattered around the country closed as the nation's swine flu caseload passed 100 Thursday, and U.S. authorities said they eventually could produce enough vaccine for everyone if necessary — but that shots couldn't begin until fall at the earliest.

The outbreak penetrated over a dozen states and even touched the White House, which disclosed that an aide to Energy Secretary Steven Chu apparently got sick helping arrange President Barack Obama's recent trip to Mexico but that the aide did not fly on Air Force One and never posed a risk to the president.

An estimated 12,000 people logged onto a Webcast where the government's top emergency officials sought to cut confusion by answering questions straight from the public: Can a factory worker handling parts from Mexico catch the virus? No. Can...