title: Increasing health burden of human babesiosis in endemic sites.
abstract: Human infection due to Babesia microti has been regarded as infrequent and a condition primarily affecting the elderly or immunocompromised. To determine whether risk in endemic sites may be increasing relative to that of Borrelia burgdorferi and to define its age-related clinical spectrum, we carried out a 10-year community-based serosurvey and case finding study on Block Island, Rhode Island. Less intensive observations were conducted in nearby sites. Incidence of babesial infection on Block Island increased during the early 1990s, reaching a level about three-fourths that of borrelial infection. The sera of approximately one-tenth of Block Island residents reacted against babesial antigen, a seroprevalence similar to those on Prudence Island and in southeastern Connecticut. Although the number and duration of babesial symptoms in people older than 50 years of age approximated those in people 20 to 49 years of age, more older adults were admitted to hospital than younger adults. Few Babesia-infected children were hospitalized. Babesial incidence at endemic sites in southern New England appears to have risen during the 1990s to a level approaching that due to borreliosis.
authors.affiliation: Department of Pediatrics, University of Connecticut School of Medicine and Connecticut Children's Medical Center, Hartford, Connecticut 06106, USA. Pkrause@ccmckids.org
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Krause
authors.forename: Kathleen
authors.initials: K
authors.lastname: McKay
authors.forename: Joseph
authors.initials: J
authors.lastname: Gadbaw
authors.forename: Diane
authors.initials: D
authors.lastname: Christianson
authors.forename: Linda
authors.initials: L
authors.lastname: Closter
authors.forename: Timothy
authors.initials: T
authors.lastname: Lepore
authors.forename: Sam R
authors.initials: SR
authors.lastname: Telford
authors.forename: Vijay
authors.initials: V
authors.lastname: Sikand
authors.forename: Raymond
authors.initials: R
authors.lastname: Ryan
authors.forename: David
authors.initials: D
authors.lastname: Persing
authors.forename: Justin D
authors.initials: JD
authors.lastname: Radolf
authors.forename: Andrew
authors.initials: A
authors.lastname: Spielman
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D041001:Babesia microti / Q000276:immunology* / Q000302:isolation & purification; D001404:Babesiosis / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003237:Connecticut / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D011446:Prospective Studies; D012237:Rhode Island / Q000453:epidemiology; D016036:Seroepidemiologic Studies
chemical_list: D000913:Antibodies, Protozoan