April 8 (Reuters) - Variants of the virus that causes COVID-19 post the biggest threat to the U.S. economic recovery, Minneapolis Federal Reserve Bank President Neel Kashkari said on Thursday. “The biggest risks that I see to the recovery are these variants,” Kashkari told the Economic Club of New York, noting the ability of one variant now thought to be dominant in parts of the United States to easily infect younger people. If daycare centers and schools need to be closed in response to the spread, he said, that could strain families and “set us back. That’s not my basecase scenario but that’s what the healthcare experts that I consult with are warning me about.” (Reporting by Ann Saphir Editing by Chizu Nomiyama)