In 2009, when the world was worried about the danger of the H1N1 influenza virus (swine flu), Representative Rosa DeLauro and Senator Edward Kennedy proposed the Healthy Families Act in Congress to guarantee paid sick days to all workers (Ellen Wu and Rajiv Bhatia, “A Case for Paid Sick Days,” San Francisco Chronicle, May 15, 2009). Although the Centers for Disease Control and Prevention urges ill people to stay home from work or school to keep from infecting others, many workers—especially those who do not receive paid sick days—ignore this advice. Evaluate the efficiency and welfare implications of the proposed law taking account of externalities.