Domestically Acquired Legionnaires’ Disease: Two Case Reports and a Review of the Pertinent Literature

Abstract

Background: Legionella species may colonize in home water systems and cause Legionnaires' disease (LD). We herein report two cases of sporadic LD associated with the solar energy-heated hot water systems of the patients' houses. Case Report: A 60-year-old woman with chronic bronchitis and diabetes mellitus presented with a high fever, abdominal pain, and diarrhea. Physical examination revealed rales, and her chest radiograph showed a homogeneous density in the left lung. The Legionella urinary antigen test was positive, and an indirect fluorescent antibody test revealed a serum antibody titer of 1/520 for L. pneumophila serogroup 1. In the second case, a 66-year-old man with diabetes mellitus was treated for pneumonia at another hospital. After the patient's general condition worsened and he required mechanical ventilation, he was referred to our hospital. The Legionella urinary antigen test was positive. Neither of the patients had been hospitalized or travelled within the previous month. Both patients used hot water storage tanks heated by solar energy; both also used an electrical device in the bathroom to heat the water when solar energy alone was insufficient. The hot water samples from the residences of both patients were positive for L. pneumophila serogroup 1. Conclusion: These cases show that domestic hot water systems heated by solar energy must be considered a possible source of community-acquired LD.

Evaluation of Legionella spp. Colonization in Residential Buildings Having Solar Thermal System for Hot Water Production

“…A difference between our previous study [ 8 ] and these data concerns the type of hot water production. In this study, an higher risk of Legionnaires disease has been observed in residential buildings with solar thermal systems.…”

“…In fact, we detected Legionella spp. in 26% of apartments in buildings provided with a centralized or independent warm water production [ 8 ]. Considering only the solar thermal systems for hot water production, the positivity percentage was higher (40%).…”

“…During the last three years, an increase of literature data on Legionella spp. presence in water networks of residential buildings has been observed [ 7 , 8 , 9 , 10 , 11 ]. Moreover, both an Italian guideline for Legionnaires’ disease control in hospital and community settings, and the Drinking Water Directive identify the responsibilities for water quality control in private residential buildings [ 12 , 13 ].…”

Colonization of<em> </em><em>Legionella </em><em>spp. </em>in Hot and Cold Water Networks of Residential Buildings in Pisa District (Tuscany, Italy): A Five-Years Survey

“…During the last three years an increase of literature data on Legionella spp. presence in water networks of residential buildings, has been observed [7,8,9,10,11]. Moreover, both an Italian guideline for Legionnaires' disease control in hospital and community settings, and the Drinking Water Directive identify the responsibilities for water quality control also in private residential buildings [12,13].…”

Legionnaires' Disease

“…Shortly after this epidemic, an outbreak of hospital-acquired Legionnaires' disease was reported [5] . This was followed by the discovery of Legionella bacterial colonization of water systems used in the homes of patients with community-acquired Legionnaires' disease, demonstrating what a widespread and significant health problem Legionella infections were [6,7] . In Turkey, Legionnaires' disease was added to the list of notifiable diseases in 1996 and special surveillance for travel-associated cases was initiated with the Legionnaires' Disease Control Program [8,9] .…”