MARK PRATT Associated Press Writer BOSTON (AP) — Many American businesses are unprepared to deal with widespread employee absenteeism in the event of an outbreak of swine flu, according to a Harvard School of Public Health study released Wednesday. The survey found that two-thirds of the more than 1,000 businesses questioned nationwide said they could not maintain normal operations if half their workers were out for two weeks. Four out of every five businesses expect severe problems if half their workers are out for a month. "What we found is that a minority of businesses have started some sort of emergency planning," said Robert Blendon, a professor of health policy and leader of the project sponsored by the U.S. Centers for Disease Control and Prevention. "Most, I don't think, have thought through the implications of something so widespread." Companies designated by the Department of Homeland Security as "critical" to the security and economic vitality of the nation, including those in the food supply chain, energy and finance, were no more likely to have a plan than non-essential businesses, Blendon said. Companies may have been fooled into complacency by the relative mild nature of the first wave of swine flu that swept the U.S. last spring, and are too concerned about the overall economic situation to worry about future problems, he said. The survey found that about three-quarters of businesses offer paid sick leave for some employees, but only 35 percent offer paid leave for workers who need to stay home to take care of sick family members or children forced to stay home if schools are closed. Those policies should be loosened during an outbreak, Blendon said. "If this hits, there is really need for some flexibility." The survey also found that nearly half of all companies required a doctor's note before granting someone sick leave, and about 70 percent required a note before someone can return to work, yet few had considered getting rid of that policy during a medical emergency. The CDC is suggesting that companies waive that rule during a flu pandemic to relieve strain on overworked doctor's offices, said agency spokesman Glen Nowak. Associated Industries of Massachusetts, which includes 6,500 companies in the state from the small to the Fortune 500, is urging its members to prepare. "Companies have to prepare now because the flu spreads so quickly there won't be enough time to make these business-critical decisions when it hits," said Karen Choi, the organization's senior vice president of management and human resources services. Companies need to train workers to handle the jobs of absent colleagues and need to determine which jobs can be handled remotely from home, she said. The telephone survey, conducted between July 16 and August 12, included interviews with human resources officers at 1,057 randomly selected businesses across the U.S. It included samples of small businesses with 20 to 99 employees; medium companies with 100 to 500 employees; and large businesses with more than 500 workers. It had a margin of error of plus or minus 4.2 percentage points. The information from the survey is already being used by the CDC to advise businesses, said agency spokesman Nowak. "This is another burden employers are going to have to face in an already difficult year," Choi said.