Outbreak of Francisella novicida bacteremia among inmates at a louisiana correctional facility.

BACKGROUND: Francisella novicida is a rare cause of human illness despite its close genetic relationship to Francisella tularensis, the agent of tularemia. During April-July 2011, 3 inmates at a Louisiana correctional facility developed F. novicida bacteremia; 1 inmate died acutely. METHODS: We interviewed surviving inmates; reviewed laboratory, medical, and housing records; and conducted an environmental investigation. Clinical and environmental samples were tested by culture, real-time polymerase chain reaction (PCR), and multigene sequencing. Isolates were typed by pulsed-field gel electrophoresis (PFGE). RESULTS: Clinical isolates were identified as F. novicida based on sequence analyses of the 16S ribosomal RNA, pgm, and pdpD genes. PmeI PFGE patterns for the clinical isolates were indistinguishable. Source patients were aged 40-56 years, male, and African American, and all were immunocompromised. Two patients presented with signs of bacterial peritonitis; the third had pyomyositis of the thigh. The 3 inmates had no contact with one another; their only shared exposures were consumption of municipal water and of ice that was mass-produced at the prison in an unenclosed building. Swabs from one set of ice machines and associated ice scoops yielded evidence of F. novicida by PCR and sequencing. All other environmental specimens tested negative. CONCLUSIONS: To our knowledge, this is the first reported common-source outbreak of F. novicida infections in humans. Epidemiological and laboratory evidence implicate contaminated ice as the likely vehicle of transmission; liver disease may be a predisposing factor. Clinicians, laboratorians, and public health officials should be aware of the potential for misidentification of F. novicida as F. tularensis.

U.S. healthcare providers' experience with Lyme and other tick-borne diseases.

Surveillance indicates that tick-borne diseases are a common problem in the United States. Nevertheless, little is known regarding the experience or management practices of healthcare providers who treat these conditions. The purpose of the present study was to characterize the frequency of tick-borne diseases in clinical practice and the knowledge of healthcare providers regarding their management. Four questions about tick-borne diseases were added to the 2009 Docstyles survey, a nationally representative survey of >2000 U.S. healthcare providers. Topics included diseases encountered, management of patients with early Lyme disease (LD), provision of tick-bite prophylaxis, and sources of information on tick-borne diseases. Overall, 51.3% of practitioners had treated at least one patient for a tick-borne illness in the previous year. Among these, 75.1% had treated one type of disease, 19.0% two types of disease, and 5.9% three or more diseases. LD was encountered by 936 (46.8%) providers; Rocky Mountain spotted fever was encountered by 184 (9.2%) providers. Given a scenario involving early LD, 89% of providers would prescribe antibiotics at the first visit, with or without ordering a blood test. Tick-bite prophylaxis was prescribed by 31.0% of all practitioners, including 41.1% in high-LD-incidence states and 26.0% in low-incidence states. Tick-borne diseases are encountered frequently in clinical practice. Most providers would treat early LD promptly, suggesting they are knowledgeable regarding the limitations of laboratory testing in this setting. Conversely, providers in low-LD-incidence states frequently prescribe tick-bite prophylaxis, suggesting a need for education to reduce potential misdiagnosis and overtreatment.