In July 1976, members of the American Legion veterans association who were gathered at a Philadelphia hotel began falling ill with a mysterious respiratory ailment that sickened 221 and killed 34. Months later, the US Centers for Disease Control announced that a new bacterium—Legionella pneumophila—had been identified as the culprit. It had spread through the hotel’s air conditioning system. In 2010, it was reported that 20% of Legionella infections may come from what surprising source? Discuss
Source: The Free Dictionary