How long would it take for symptoms of Legionnaires’ disease to appear?

I have previously corresponded with you last year about a case against our hot tub company. If you do not mind, I have a few more questions for you.

Are there any symptoms of Legionella infection before 48 hours? All nine of the patients were ill between 8-24 hours of the alleged exposure and it is my understanding that there would be no symptoms that soon. None of the patients have tested positive for Legionella in blood or urine samples. One of the patients even had three antigen tests done in the following months.

 

There is no objective evidence of Legionnaires’ disease – pneumonia which can be life threatening – in the above question. Most patients will show evidence of Legionnaires’ disease by blood or urine tests.

Follow-Up:

The water sample from our hot tub showed the presence of the Legionella bacteria, but it had been in transport for 144 hours until it arrived at the testing center. Could this transport time affect the results?

Reply:

Legionella grows readily in water at room temperature. The time of transport will have little effect on the presence of Legionella – either in increasing or decreasing the number.

Follow-Up:

Public health was called onsite, they saw the hot tub, and immediately declared that it was the source of the infection. They did not investigate any other possible sources. Are there food-borne bacteria that cause symptoms similar to what these patients experienced?

Public health stated that the hot tub was the source of Legionnaires’ to all the parties before any testing had been done. I believe that Legionella may be in a high percentage of hot tubs but the rate of incidence is very low because it is overstated as a source.

Reply:

You did not list the symptoms that the patients had. Typical symptoms of Legionnaires’ are high fever, cough, and presence of pneumonia on a chest x-ray. Unless the drinking water was also tested, it is inappropriate and unscientific for Public Health to conclude that the Legionnaires’ disease was contracted from the hot tub.