hello there, The incubation period of Legionnaires disease is from two to ten days; this is the time it takes before symptoms of the illness appear after being exposed to the bacteria. The symptoms include tiredness and weakness with high fever often greater than 39.5°C (103°F). Cough can be the first sign of a lung infection. The cough may be sufficiently severe to cause sputum production (coughed up mucous). Gastrointestinal stomach symptoms are common with diarrhea being the most distinctive symptom. Many patients have nausea, vomiting, and stomach discomfort. Other common symptoms include headaches, muscle aches, chest pain, and shortness of breath. Legionnaires disease is not contagious. No special precautions are necessary. The disease is transmitted via drinking water, not by infected persons. Likewise, women who are pregnant and their fetuses have nothing to fear from patients with Legionnaires disease. So if your daughters had legionnaire s disease, you have nothing to worry from them if you directly didnot consume the infected water. Moreover you said it was 20days back, so if you had also acquired infection, you would have developed the above symptoms by now considering the incubation period to be 2-10days. But hteres no harm in taking a diagnostic test to confirm that you are not infected. Specialized laboratory tests are necessary and, unfortunately, may not be available in many hospitals. These include culture on specialized Legionella media. Culture media furnish nutrients for the bacterium. When sputum from the patients are placed onto the culture media, the bacterium grows on the medium and can be identified. Other tests include direct fluorescent antibody (DFA) in which the bacterium can be stained and becomes visible under a fluorescent microscope. Antibody testing is a blood test in which antibodies that are reactive against Legionella are present in the human body showing that the patient has come into contact with the bacterium previously. Urinary antigen is a test that detects Legionella in the urine. Many antibiotics are highly effective against Legionella bacteria. The two most potent classes of antibiotic are the macrolides (azithromycin), and the quinolones (ciprofloxacin, moxifloxacin etc) But quinolones are not safe in pregnancy. So i suggest you meet a physician personally, ask for blood test and if needed the antibiotic.