The Vermont Department of Health has confirmed five cases of Legionnaires' disease in Franklin County clustered in the St. Albans area.Officials said the cases were reported to the Health Department between Aug. 12 and Aug. 29. The source of the infection is currently unknown.One person in their 70s has died as a result of the disease. However, officials said the general risk to area residents is very low, as most healthy people do not get sick after being exposed to the bacteria that causes Legionnaires' disease.Legionnaires' disease is a form of pneumonia caused by Legionella bacteria. It is not contagious and does not spread from person to person, the Health Department said. Symptoms include cough, muscle aches and fever.Those most at risk of infection include people ages 50 and over who smoke or have smoked or have other respiratory conditions. The condition can be treated in most cases with antibiotics and is typically not deadly. Health officials said Legionnaires' disease is commonly found in stagnant freshwater, where bacteria is able to thrive. This includes water systems of buildings, including air conditioning units for large buildings, also known as cooling towers, as well as decorative fountains and plumbing systems.