In the next six weeks, the administration will send vaccines to up to 700 more community health centers that typically serve lower-income patients, bringing the total number of those sites serving as vaccination centers to 950.More than 20,000 pharmacies will now administer the shots as part of the federal government’s pharmacy vaccine program, double the number that have so far participated.The administration is more than doubling the number of federally run mass vaccination sites, settings that the White House said would now be able to administer hundreds of thousands of shots a day under the aegis of the Federal Emergency Management Agency, the military and other agencies. At least 4,000 more active duty troops are to be deployed to help the effort.