Israel Medical Association Journal

Background: Leptospirosis is a zoonotic disease that occurs worldwide, found predominantly in agricultural workers, port workers and dairy workers.

Objective: To investigate the risk of disease transmission to dairy workers following an outbreak in 1999 of Leptospirosis hardjo in the dairy herds of two kibbutzim in southern Israel.

Methods:  A seroepidemiologic survey of all the dairy workers from these two kibbutzim was conducted, including individual interview and examination. Data were collected on the presence of clinical symptoms of leptospirosis during the previous month. One month later the medical personnel on the two kibbutzim were contacted in order to determine if any worker had subsequently developed clinical signs or symptoms of leptospirosis. All dairy workers had blood drawn for serology. Those workers whose initial serology had been borderline for leptospirosis had a repeated serology test between 2 and 4 weeks later. Doxycycline was given prophylactically to all dairy workers on one kibbutz only.

Results:  Either with or without chemoprophylaxis, no dairy workers exposed to herds infected with Leptospira hardjo showed evidence of seroconversion or disease. This indicated a low risk of transmission of this serovar from cows to dairy workers.

Conclusion: Since human illness with leptospirae can cause illness associated with significant morbidity we recommend that dairy workers exposed to an infected herd receive doxycycline prophylaxis.

Background: We treated two patients diagnosed with legionellosis and simultaneous Rickettsia conorii co-infection.

Objectives: To report the clinical and laboratory characteristics of this unusual combination, and to describe the execution and results of our environmental and epidemiologic investigations.

Methods: Serial serologic testing was conducted 1, 4 and 7 weeks after initial presentation. Water samples from the patients’ residence were cultured for Legionella. Follow-up cultures were taken from identical points at 2 weeks and at 3 months after the initial survey.

Results: Both patients initially expressed a non-specific rise in anti-Legionella immunoglobulin M titers to multiple serotypes. By week 4 a definite pattern of specifically elevated IgG[1] titers became apparent, with patient 1 demonstrating a rise in specific anti-L. pneumophila 12 IgG titer, and patient 2 an identical response to L. jordanis. At 4 weeks both patients were positive for both IgM and IgG anti-R. conorii antibodies at a titer ³ 1:100. Heavy growth of Legionella was found in water sampled from the shower heads in the rooms of both patients. Indirect immunofluorescence of water cultures was positive for L. pneumophila 12 and for L. jordanis.

Conclusions: Although most cases of community-acquired Legionella pneumonia in our region appear simultaneously with at least one other causative agent, co-infection with R. conorii is unusual and has not been reported to date. This report illustrates the importance of cooperation between clinicians and public health practitioners.