Bellevue Stratford Hotel (FIRST CASE)
On July 21-24, 1976, the Bellevue-Stratford Hotel in Philadelphia
hosted the 58th Pennsylvania State Convention of the American
Legion. More than 4,000 World War II Legionnaires took part in
the event. Approximately 600 of them stayed at the Bellevue-Stratford.
The day after the convention opened, a number of the participants
became ill. The symptoms were flu-like and consisted of fever,
coughing, breathing difficulties, chest pains, lung congestion
and pneumonia. In the days that followed the convention, the still
unidentified disease killed 34 participants and infected 221,
all of whom had spent time at the hotel. The ages of those who
died ranged from 39 to 82 years.
On January 18, 1977, scientists discovered the cause of the Philadelphia
deaths, a bacterium that had not yet been named. On November 18,1978,
the bacterium was given a scientific name: Legionella (to honor
the victims of the Legionnaires' convention) pneumophila (pneumonia
symptoms that occurred in Philadelphia). The disease became commonly
known as Legionnaires' disease.
Researchers still had to determine how the disease was transmitted.
Legionella pneumophila resembled bacteria that one researcher
had found in the thermal regions of Yellowstone National Park,
where it tended to live as biofilm (scum) associated with certain
species of algae. Subsequently, scientists began investigating
aquatic habitats and found the bacteria residing in thermal waters
discharged from a nuclear reactor at Savannah River Laboratory,
in natural hot springs all over the United States and in air conditioning
Of the 221 people who became sick in Philadelphia, 72 were people
not involved in the American Legion convention. These people had
either been inside the Bellevue-Stratford Hotel or had walked
past it. The Legionnaires' disease bacillus was actually spread
by the air conditioning system in aerosolized water droplets.
People who inhaled the aerosols also inhaled the microorganisms,
which were brought into the respiratory tract. There they multiplied
without interference from the immune system, causing flu-like
symptoms and, when left untreated, pneumonia that resulted in
death. Other outbreaks and epidemics occurring throughout the
world since then have revealed that the occurrence of Legionella
in manmade environments was not restricted to cooling towers alone;
that wherever on earth there was a machine that could produce
mist, there was Legionella and Legionnaires' disease. It was later
found that the bacteria could also colonize and amplify (the exponential
growth of the organism) in domestic water systems, such as the
hot water system.