Babesiosis in Fairfield County, Connecticut

progression and viral load in a community outbreak of coronavirus-associated SARS pneumonia: a prospective study. 5. WHO hospital discharge and follow-up policy for patients who have been diagnosed with severe acute respiratory syndrome (SARS) [monograph on the Internet]. To the Editor: Human babesiosis, caused by Babesia microti, was initially described in the eastern United States in 1970 in a woman vacation-ing on Nantucket Island, Massachusetts (1). With few exceptions , almost all subsequent cases were recorded from islands in the northeastern United States and Cape Cod, Massachusetts (2), until this illness was diagnosed in 13 patients living in New London County in southeastern Connecticut (3,4). B. microti was isolated from white-footed mice, Peromyscus leucopus, captured from 1988 to 1990 in the yards of patients. Babesiosis also was diagnosed in persons living in Wisconsin (5) and in New Jersey (6) who acquired the organism locally. The number of cases of babesiosis reported by health departments on their Web sites and by personal communication in Massa-chusetts, Rhode Island, and New York diagnosed in 230 persons residing in New London County and adjacent Middlesex County, Connecticut (7). Fifty-three additional cases were reported in five other counties in Connecticut, but epidemiologic data did not indicate that these infections likely were acquired within Connecticut. We now note a new and distinct geographic focus by reporting the isolation of B. microti from rodents captured in the yards of two patients in whom babesiosis was diagnosed at Greenwich Hospital in 2002. These patients lived in Greenwich, Connecticut, which is located in Fairfield County in the extreme southwestern part of the state. Neither patient had traveled outside of the immediate area of Greenwich, Connecticut, before onset of illness. We also trapped rodents in the yards of two additional patients in whom babesiosis was diagnosed. These two patients had traveled to Rhode Island shortly before becoming ill. Patients became ill from June 23 to July 7, 2002, and none reported a tick bite. Attempts to trap small mammals on the properties of the four patients were made on July 22, 23, and 29, 2002. Rodents were captured in Sherman box traps baited with peanut butter and apple. Approximately 0.3 mL of blood was drawn from the heart of each animal into a syringe coated with heparin or uncoated. Blood was kept on ice in the field and then returned to the laboratory. A 3-to 5-week-old male Syrian hamster was …