USA TODAY Concerned about new variants of the virus that causes COVID-19, the U.S. Food and Drug Administration announced late Thursday that it is developing guidance to help vaccine, drug and testing manufacturers adapt. Existing vaccines, treatments and tests still work well, emphasized the FDA's acting commissioner Janet Woodcock. But now is the time to get ready for a future when they may not. "We must prepare for all eventualities," she said in a call with reporters. Within the next few weeks, the FDA will provide draft guidance to manufacturers on how to adapt their products as needed, Woodcock said. Feedback from companies and others will help refine that guidance.