Leptospirosis is frequently misdiagnosed as a result of its protean and nonspecific presentation. Leptospirosis, a zoonosis with global distribution, commonly occurs in tropical and subtropical regions; most reported cases in the United States occur in Hawaii. All laboratory-confirmed leptospirosis cases in the State of Hawaii from 1974 through 1998 (n=353) were clinically evaluated. The most common presentation involved nonspecific signs or symptoms, including fever, myalgia, and headache. Jaundice occurred in 39% of cases; conjunctival suffusion was described in 28% of these cases. Initiation of antibiotics before the seventh day of symptoms was associated with a significantly shortened duration of illness. Because early recognition and initiation of antibiotic therapy are important, clinicians should familiarize themselves with the clinical presentation of leptospirosis, and when evaluating a patient with a febrile illness, they should obtain exposure and travel histories and entertain the possibility of leptospirosis in the differential diagnosis.

The authors and associates conducted a social norms-based intervention targeting high-risk sexual behaviors among undergraduate students at 4 college campuses. Social norms theory predicts that widely held misperceptions may encourage risky behavior in a misguided attempt to conform to perceived norms and that information correcting these misperceptions will lead to a decrease in such behaviors. Students overestimated their peers' levels of sexual activity, numbers of partners, incidence of sexually transmitted infections, and rates of unintended pregnancies, but underestimated rates of condom use. Rates of HIV test taking, however, were accurately estimated. Although some components of sexual risk behaviors lend themselves well to social norms-based interventions, others, specifically inconsistent condom use and avoiding HIV tests, do not. Although no changes in reported beliefs or practices were apparent at the end of a 9-month intervention period, longer or modified interventions may be needed to make a fair assessment of the efficacy of this approach.

Leptospirosis is a major public health problem throughout the world. Clinical recognition of leptospirosis is challenging, and the definitive serologic diagnostic assay, the microscopic agglutination test, is timeconsuming and difficult to conduct. Various serologic screening tests have been developed, but their performance among ill persons in the United States has not been established. Eight screening tests were compared using 379 serum samples obtained in 1998 and 1999 from a series of 236 patients (33 with confirmed infection). The median number of days between illness onset and specimen collection was 9. The overall sensitivity, by specimen, for each test was as follows: indirect hemagglutination assay (MRL Diagnostics, Cypress, Calif.), 29%; INDX Leptospira Dip-S-Tick (PanBio InDx, Inc., Baltimore, Md.), 52%; Biognost IgM IFA test (Bios GmbH Labordiagnostik, Gräfelfing, Germany), 40%; Biolisa IgM ELISA (Bios GmbH, Labordiagnostik), 48%; Leptospira IgM ELISA (PanBio Pty Ltd., Brisbane, Australia), 36%; SERION ELISA classic Leptospira (Institut Virion•Serion GmbH, Würzburg, Germany), 48%; LEPTO Dipstick(Organon-Teknika, Ltd., Amsterdam, The Netherlands), 34%; Biosave latex agglutination test (LATEX; Bios GmbH Labordiagnostik), 86%. Test specificity ranged from 85 to 100% among all tests except LATEX, for which the specificity was significantly lower, at 10%. Test sensitivity was particularly low (<25%) for all tests (except LATEX) on specimens collected during the first week of illness. This is the most comprehensive field trial of leptospirosis screening tests reported to date. The data indicate that immunoglobulin M detection tests have limited utility for diagnosing leptospirosis during the initial evaluation of patients seen in Hawaii, a time when important therapeutic decisions are made. Improved leptospirosis screening tests are needed.

On October 31, 2004, a stream overflowed, flooding the University of Hawaii (UH) campus. On November 19, 2004, a possible flood-related leptospirosis case (Patient 1) was reported to the Hawaii State Department of Health (HDOH). Surveillance for febrile illness was established through an Internet questionnaire. Active case finding was conducted among groups involved in the flood clean-up. Free leptospirosis testing was offered by HDOH. Patient 1's illness was confirmed as leptospirosis by microscopic agglutination testing. A total of 271 persons responded to the Internet survey, of whom 90 (33%) reported a febrile illness within 30 days of contact with flood water. Forty-eight respondents (18%) were tested for leptospirosis. One additional acute leptospirosis case was identified. Patient 2 was epidemiologically linked to Patient 1. Health care providers should maintain a high level of suspicion for leptospirosis after flooding events, and local public health officials should promote leptospirosis awareness among flood-affected populations.

The recent unexplained increase in severe streptococcal diseases in the United States and Great Britain is compared to the 1825-1885 pandemic of fatal scarlet fever. Although scarlet fever may not be representative of all severe streptococcal disease, it was the only one reliably identified in the 19th century. The epidemiology of scarlet fever during the 19th century pandemic suggests the following features of the disease; cocirculation of both virulent and less-virulent streptococcal strains eliciting cross-immunity; circulation of hyperendemic prevalent strains in urban centers of developed nations, with periodic spillovers to rural areas and developing nations; and protection of infants from infection (but not from fatal disease once infection occurred) by the transfer of maternal antibodies via the placenta, breast milk, or both. The 19th century data suggest that efforts to prevent severe streptococcal diseases should begin with better characterization of the epidemiology of streptococcal disease, a task entailing identification of streptococcal virulence factors and measurement of their distribution among isolates from individuals with streptococcal diseases and in open populations.