Transfusion-transmitted babesiosis in Rhode Island.
BACKGROUND
Babesiosis is caused by an intraerythrocytic protozoan transmitted by ticks. Blood transfusion is another mode of transmission.


METHODS
This was a retrospective study based on babesiosis cases reported to the Rhode Island Department of Health between 1999 and 2007. Additional cases were also identified.


RESULTS
Twenty-one cases of transfusion-transmitted babesiosis (TTB) were identified from 1999 through 2007. From 2005 through 2007, the incidence approached one case per 9000 units of blood transfused. One of 21 (5%) TTB cases was diagnosed in July, in sharp contrast to 65 of 152 (43%) of the total babesiosis cases diagnosed during July in Rhode Island. Many cases were identified when a complete blood count with a differential was routinely requested and parasites were noted by laboratory technologists. Most patients with TTB had underlying conditions known to predispose to symptomatic infection.


CONCLUSIONS
Blood transfusion is an important mode of Babesia transmission. The current screening method of omitting donors with a history of babesiosis may be effective in preventing some, but not all, cases of TTB and current processing of blood products does not eradicate this parasite. Thus, a better screening test is needed. Alternatively, pathogen reduction technology could be utilized to prevent this mode of transmission.
Asad
Shadaba
S
Division of Infectious Diseases, Department of Medicine, and Transfusion Medicine, Rhode Island Hospital, Providence, RI 02903, USA.
Sweeney
Joseph
J
Mermel
Leonard A
LA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000962:Antimalarials / Q000627:therapeutic use; D001404:Babesiosis / Q000188:drug therapy / Q000453:epidemiology* / Q000635:transmission*; D001782:Blood Donors / Q000706:statistics & numerical data; D002675:Child, Preschool; D018562:Disease Transmission, Infectious / Q000706:statistics & numerical data; D017707:Erythrocyte Transfusion / Q000009:adverse effects* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D055256:Infectious Disease Incubation Period; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D012237:Rhode Island / Q000453:epidemiology; D012621:Seasons; D017282:Tick-Borne Diseases / Q000453:epidemiology; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D000962:Antimalarials