Legionnaires' disease Legionnaires' disease Legionnaires' disease, also known as legionellosis, is a form of atypical pneumonia caused by any type of "Legionella" bacteria. Signs and symptoms include cough, shortness of breath, high fever, muscle pains, and headaches. Nausea, vomiting, and diarrhea may also occur. This often begins 2-10 days after exposure. The bacterium is found naturally in fresh water. It can contaminate hot water tanks, hot tubs, and cooling towers of large air conditioners. It is usually spread by breathing in mist that contains the bacteria. It can also occur when contaminated water is aspirated. It typically does not spread directly between
Disease in colonial America and is extremely contagious, for it is spread by physical contact and affects children and adults alike. Smallpox was contagious, disfiguring, and often deadly. The epidemics of the disease were recurrent, devastating, and frequent. A particularly virulent sequence of smallpox outbreaks took place in Boston, Massachusetts. From 1636 to 1698, Boston endured six epidemics. In 1721, the most severe epidemic occurred. The entire population fled the city, bringing the virus to the rest of the Thirteen Colonies. Colonists tried to prevent the spread of smallpox by isolation and inoculation. Inoculation caused a mild form of the disease; it was new