Thankyou for the clarification Gail.I was unaware of the 1976 incident.The case of encephalitis I was refering to happened around 1969 or so.I do know that it was prior to 1972 when I first visited Deep Creek.I dont mean to panic anyone as this disease is very rare.The young and Immunocomprimised are at greater risk.Legionella on the other hand,is much more common in our environment.It has been associated with airconditioning systems in large buildings and other moist environments.Potentialy fatal,it is treatable with antibiotics.