ABSTRACT: Leptospirosis is the most widespread zoonotic illness globally. It has been classified by the World Health Organization and the U.S. Centers for Disease Control and Prevention (CDC) as emerging or re-emerging. Leptospirosis is most frequently recognized in the developing world. It was removed from the U.S. list of nationally reportable infectious diseases in 1995, except in the state of Hawaii, which has always recorded the highest rates in the U.S. The last population-based surveillance report from Hawaii covered the years 1974-1998. This article updates the situation during 1999-2008.
CONCLUSIONS: The incidence of leptospirosis is more than 100 times greater in the state of Hawaii than in the mainland U.S. The epidemiology has changed over the past 30 years, but rates have remained steady. Travel has become the most important source of leptospirosis in developed countries, mainly through participation in fresh water sports in Southeast Asia. Although not a common cause of fever in the returning traveler, leptospirosis may carry serious complications. Prevention and prompt diagnosis are important.