Clinical characteristics and functional outcomes of West Nile Fever.

BACKGROUND: West Nile fever, considered a nonsevere manifestation of West Nile virus infection, has not been clinically well described in the United States. In 2002, Illinois had 884 documented cases of West Nile virus infection with 66 associated deaths. OBJECTIVE: To describe the symptoms and functional outcomes of West Nile fever. DESIGN: Case series. SETTING: Illinois. PATIENTS: 98 community-dwelling patients with laboratory evidence of West Nile virus infection but no history of clinical evidence of meningitis, encephalitis, or acute flaccid paralysis. INTERVENTION: Outpatient interviews. MEASUREMENTS: Presence and duration of patient-reported symptoms of infection, symptom-associated absenteeism, health care use, and impact on daily activities. RESULTS: Of 98 patients, 96% had fatigue for a median of 36 days, 81% had fever for a median of 5 days, 71% had headache for a median of 10 days, 61% had muscle weakness for a median of 28 days, and 53% had difficulty concentrating for a median of 14 days. Thirty respondents reported hospitalization, with a median stay of 5 days. At 30 days after onset, 63% of respondents continued to have symptoms. Duration did not vary significantly with increased age. Among the 72 patients who normally attended work or school, 57 (79%) could not attend because of illness (median absence, 10 days). LIMITATIONS: Recall bias could have been introduced by the delay between illness onset and interview and by self-reporting of illness information. CONCLUSIONS: West Nile fever is a more severe illness than has previously been documented. Mandatory reporting of West Nile fever cases in addition to West Nile meningoencephalitis cases could allow more accurate and timely recognition of the geographic distribution of West Nile virus infections and could inform public health interventions.

Outbreak of leptospirosis among triathlon participants and community residents in Springfield, Illinois, 1998.

We investigated an outbreak of leptospirosis among athletes and community residents after a triathlon was held in Springfield, Illinois. A telephone survey was conducted to collect clinical information and data on possible risk factors, community surveillance was established, and animal specimens and lake water samples were collected to determine the source of the leptospiral contamination. A total of 834 of 876 triathletes were contacted; 98 (12%) reported being ill. Serum samples obtained from 474 athletes were tested; 52 of these samples (11%) tested positive for leptospirosis. Fourteen (6%) of 248 symptomatic community residents tested positive for leptospirosis. Heavy rains that preceded the triathlon are likely to have increased leptospiral contamination of Lake Springfield. Among athletes, ingestion of 1 or more swallows of lake water was a predominant risk factor for illness. This is the largest outbreak of leptospirosis that has been reported in the United States. Health care providers and occupational and recreational users of bodies of freshwater in the United States should be aware of the risk of contracting leptospirosis, particularly after heavy rains.