Israel Medical Association Journal

Abstract

During recent months, the Centers for Disease Control and Prevention (CDC) announced the occurrence of three major biosafety incidents, raising serious concern about biosafety and biosecurity guideline implementation in the most prestigious agencies in the United States: the CDC, the National Institutes of Health (NIH) and the Federal Drug Administration (FDA). These lapses included: a) the mishandling of Bacillus anthracis spores potentially exposing dozens of employees to anthrax; b) the shipment of low pathogenic influenza virus unknowingly cross-contaminated with a highly pathogenic strain; and c) an inventory lapse of hundreds of samples of biological agents, including six vials of variola virus kept in a cold storage room for decades, unnoticed. In this review we present the published data on these events, report the CDC inquiry’s main findings, and discuss the key lessons to be learnt to ensure safer scientific practice in biomedical and microbiological service and research laboratories.

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.