I'm not sure how we got from cancer to legionellosis, but you are making my point, so we must be in at least partial agreement. And that point is that misdiagnosis happens too often, as we all read on these boards, and in your husband's case with the flu that was actually legionellosis. If that first year intern suspected legeionella, I guarantee you he didn't diagnosis it from recognizing the symptoms. There is a very specific test for it as symptoms vary wildly from patient to patient. Patients with Legionnaires' disease usually have fever, chills, and a cough, which may be dry or may produce sputum. Some patients also have muscle aches, headache, tiredness, loss of appetite, and, occasionally, diarrhea. Laboratory tests may show that these patients' kidneys are not functioning properly. Chest X-rays often show pneumonia. It is difficult to distinguish Legionnaires' disease from other types of pneumonia by symptoms alone; other tests are required for diagnosis. Which is my point. Unless a specific test is done for Legionella pneumophila, and that bacterium was specifically identified, the doctors would not know what antibiotic, in this case erythromycin, or in severe cases rifampin, to prescribe. Guessing what antibiotic, based on symptoms and not on a definitive test related pathological finding, is Russian roulette. In your husband