Babesia spp. Emerging Transfusion Dilemmas David A. Leiby, PhD Transmissible Diseases Department American Red Cross Holland Laboratory Department of Microbiology and Tropical Medicine George Washington University Holland Laboratory
Historical Origins of Babesia Behold the hand of the Lord is upon thy cattle which is in the field, upon the horses, upon the asses, upon the camels, upon the oxen and upon the sheep: there shall be a very grievous murrain. Exodus 9:3 murrain = medieval term for diseases of high morbidity all animals mentioned above susceptible to Babesia Irish countryside, cattle babesiosis still called murrain Earle, DP. Trans Am Clin Climatol Assoc 1989;100:132-141.
Babesia First Identified Dr. Victor Babes Romanian scientist Professor of Pathology and Bacteriology at the Faculty of Medicine in Bucharest in 1888, Babes described a gram-staining intraerythrocytic bacterium infecting ~ 50,000 cattle that died each year in Romania during the late 19 th century initially designated parasite as Heamatococcus bovis unable to decipher transmission of the agent
Establishing Tick-Borne Transmission Theobold Smith, MD joined U.S. Bureau of Animal Industries in 1884 assigned to investigate Texas cattle fever destroyed 90% of herds in affected areas 1889 described infected cattle erythrocytes 1893 - published seminal paper with F.L. Kilbourne demonstrating ticks (Boophilus microplus) as carriers of Texas cattle fever first description of pathogens transmitted by insects
Smith & Kilbourne, 1893 Earle, DP. Trans Am Clin Climatol Assoc 1989;100:132-141.
Babesia spp. agents of human babesiosis: B. microti, B. divergens & B. duncani CA-1, MO-1, EU-1, KO-1,TW-1, etc. infect red blood cells, but occasionally found extracellular transmitted by Ixodes ticks often same species that locally transmits Lyme borreliosis causes flu/malaria-like illness, but can be fatal in: infants elderly immunocompromised asplenic
Life-Cycle: Babesia spp.
First Human Cases of Babesiosis 33-year-old tailor from Strmec, ~ 10 km from Zagreb admitted with chocolate-brown colored skin, fever, anemia, and hemoglobinuria urinated pure blood splenectomy ~ 11 years earlier intraerythrocytic elements noted on blood smear identified as B. bovis, but likely B. divergens local cattle infected with B. divergens
Once Upon a Time... B. microti B. divergens
Babesia in Europe historically focused on B. divergens ~ 30 cases in humans; all asplenic current picture much more complicated EU1 first described in 2003 distinct from, but related to B. divergens, linked to first cases in Italy and Austria subsequently reported in Germany midwestern Germany (2002) B. divergens: 17 of 467 (3.6%) B. microti: 25 of 467 (5.4%) Eastern Switzerland (2002) B. microti: 5 0f 396 (1.5%) blood donors likely overlooked and underreported B. microti B. divergens EU1 multiple babesial agents
Babesia in the U.S. 1993 B. duncani on West Coast 1996 MO1 in Missouri 1999 B. microti reported in New Jersey 2002 B. divergens in Kentucky other miscellaneous Babesia B. microti B. divergens B. duncani MO-1
Parasitemia in CT Blood Donors 1999-2007 Year # Tested Antibody + (%) PCR + (%) 1999 3,490 30 (0.9) 10/19 (53) 2000 2,681 28 (1.0) 10/18 (56) 2001 2,162 30 (1.4) 2/25 (8) 2002 2,230 18 (0.8) 2/14 (14) 2003 1,989 34 (1.7) 2/20 (10) 2004 2,864 43 (1.5) 1/33 (3) 2005 1,841 25 (1.4) 0/10 (0) 2006 3,251 39 (0.9) 3/19 (16) 2007 5,267 42 (0.8) 1/22 (5)
County Results 2000-2008 County # IFA Positive/# IFA Test (% Seropositive) Fairfield 17/3737 (0.5) Hartford 26/4690 (0.6) Litchfield 6/1616 (0.4) Middlesex 43/3167 (1.4) New Haven 15/2907 (0.5) New London 161/9634 (1.7) Tolland 7/787 (0.9) Windham 7/1040 (0.7)
Seroprevalence/10,000 donations with spatial clusters Spatial cluster 1 Spatial cluster 2 Johnson et al., Transfusion 2009;49:2574-2582
Babesia Natural History Study long-term, ongoing study in CT and MA enrolling B. microti seropositive donors tested every 30-60 days serology blood smear PCR hamster inoculation risk-factor questionnaires initial risk potential re-exposure investigate infection/resolution patterns over time
Resolution of Babesia Infection Date IFA PCR Hamster 07/21/00 1:512 ND ND 08/15/00 1:256 Pos. Pos. 09/18/00 1:128 Pos. Neg. 12/01/00 1:128 Neg. Neg. 04/06/01 <1:64 Neg. Neg. 07/13/01 <1:64 Neg. Neg. 10/12/01 <1:64 Neg. Neg. Released from study
Persistent High Ab Titer = Chronic Carrier Date IFA PCR Hamster 08/24/00 1:512 ND ND 10/02/00 1:512 Pos. Pos. 11/28/00 1:512 Neg. Pos. 11/30/00 initiated 10 day treatment for babesiosis 03/30/01 1:512 Neg. Neg. 05/31/01 1:512 Neg. Neg. 09/10/01 1:256 Neg. Neg. 12/01/01 1:512 Neg. Neg. 02/25/02 1:512 Neg. Neg. 07/18/03 1:512 Neg. Neg. Released from study
Subject # 03-0367* Date IFA PCR RT-PCR Hamster 07/31/03 1:1024 ND ND ND 08/26/03** 1:1024 Pos. Pos. Pos. 08/29/03 initiated 10 day treatment for babesiosis 09/22/03 1:1024 Neg. Neg. Neg. 10/23/03 1:256 Neg. Pos. Neg. 01/02/04 1:1024 Neg. Pos. Neg. 03/16/04 1:1024 Pos. Pos. Neg. 04/27/04 1:1024 Neg. Pos. Neg. 06/26/04 1:1024 Neg. Pos. Neg. 09/23/04 1:1024 Neg. Pos. Neg. 11/29/04 1:128 Neg. Neg. Neg. 01/21/05 1:1024 Neg. Neg. Neg. 03/28/05 1:512 Neg. Neg. Neg. 05/17/05 1:512 Neg. Pos. Neg. 07/12/05 1:256 Neg. Pos. Neg. 09/19/05 1:256 Neg. Neg. Neg. 12/02/05 1:512 Neg. Neg. Neg. 03/07/06 1:512 Neg. Pos. Neg. 06/28/06 1:512 Neg. Neg. Neg. * 79 year-old male ** positive on blood smear
Babesia Transmission to Blood Recipients Year Donors Tested IFA Positive (%) PCR Tested PCR Positive (%) Lookbacks Positive 1999 3669 30 (0.8%) 19 10 (52.6%) 2000 2681 28 (1.0%) 18 9 (50.0%) 2001 2162 30 (1.4%) 25 1 (4.0%) 2002 2230 18 (0.8%) 14 2 (14.3%) 2003 1989 34 (1.7%) 20 2 (10.0%) 2004 2864 43 (1.5%) 33 1 (3.0%) 5/17 3/13 0/21 2005 851 17 (2.0%) 6 0 0/8 990 (new cutoff control) 8 (0.8%) 4 0 0/4 Total 17436 208 (1.2%) 139 25 (18.0%) 8/63
Factors Driving Mitigation Efforts FDA Workshop AABB Association Bulletin publications education past failures to act 80 to 100 transmission cases with rising fatalities (n>12)
B. microti: Survival In Blood Products survives in red cells maintained at 4 o C 21 days experimentally 35 days in association with transfusion case survives indefinitely in cryopreserved red cells parasite killed in frozen plasma extracellular parasites reported pose potential issues for platelet apheresis & fresh plasma products
Transfusion-Transmitted Babesia > 80 cases associated with B. microti 3 cases associated with B. duncani 0 cases associated with other species, types, strains, etc.
First Case of TTB?
B. microti: Transfusion Cases > 80 known cases worldwide (1979 - present) 1 in Japan (autochthonous) 1 in Canada (U.S. derived) rest in U.S. ~ 10 per year one possible case in Europe Hildebrandt et al., Eur J Clin Microbiol Infect Dis 2007;26:595-601 recipients - neonates to 79 years fatalities increasingly reported red cells and whole blood platelets implicated no licensed tests gaining traction as critical blood safety issue
ARC Hemovigilance: 2005-2007 suspected transfusion-transmitted B. microti infections reported by transfusion services additional cases through recipient tracing donor follow-up samples tested by IFA and PCR 19 cases transfusion-transmitted B. microti 5 fatalities 18 RBC units (1 split unit) Tonnetti et al., Transfusion 2009;49:2557-2563
Recipient Data 13 (68%) were 61-84 years old 2 (11%) < 2 years old 4 asplenic 2 had sickle cell disease (1 asplenic) incubation period: 23 384 days 5 of 19 (26%) died within days to weeks of diagnosis Tonnetti et al., Transfusion 2009;49:2557-2563
Donor Data 18 donors implicated all IFA positive; only 1 PCR positive 12 residents of endemic areas (8 CT, 3 NJ & 1 MA) 4 traveled to endemic areas - OH to CT, OH to NJ, IN to WI, VA to CT - 2 implicated in fatal cases 1 lost to follow-up & 1 unclear travel history none recalled symptoms, only 3 reported tick bite Tonnetti et al., Transfusion 2009;49:2557-2563
Mitigation Strategies UDHQ history of babesiosis * geographic exclusion* risk-factor questions leukoreduction pathogen reduction serologic screening NAT testing * currently in use
History of Babesiosis single question on UDHQ Have you ever had babesiosis? limited data on effectiveness Tonnetti et al., Transfusion 2009;49:2557-2563 2005-2007: only 123 ARC donors deferred data confounded by same deferral code used for Chagas 32 (26%) and 19 (15%) of these deferrals occurred in the Connecticut and New England regions only captures donors diagnosed with infection misses donors with asymptomatic, mild or misdiagnosed infections
Geographic Exclusion defer based on endemic states or regions unacceptable donor loss B. microti B. duncani defer only in highly endemic areas New London and Middlesex Counties, CT endemic areas difficult to define deferral based on seasonal geographic exclusion NYBC avoids areas east of the Shinecock Canal during the summer infected, parasitemic donors present year-round
Tick Bites as a Risk Factor not very useful up to 9% of donors regionally report tick bites infected patients often do not recall tick bite no significant difference: tick-bites (1.3/0.4 %) vs. controls (1.3/0.3 %) donors reporting tick bite: less likely to be infected more vigilant remove ticks promptly Leiby et al., Transfusion 2002;42:1585-1591
Leukoreduction intraerythrocytic parasite negligible impact transmission cases associated with leukoreduced products
Pathogen Reduction efficacy demonstrated amotosalen + UV light Grellier et al., Transfusion 2008;48:1676-1684. riboflavin + UV light Tonnetti et al., Transfusion 2010;50:1019-1027 studies limited to apheresis plasma and platelets presently, not a viable option in the absence of a whole blood methodology untreated riboflavin + UV
Blood Screening Approaches universal screening regional testing statewide testing highly endemic area testing CMV model... if we only had a test!
Piloting NAT Testing pilot study of 1,000 CT donations collected August/October 2009 from Middlesex and New London Counties 1,002 tested to date: 25 (2.5%) IFA positive 3 (0.3%) PCR positive (2 IFA +, 1 IFA -) all identified by first week of September 1 apparent window period infection detected number likely low acutely infected donors too sick to donate? role for NAT testing during tick season?
Babesia NAT Approach seasonally triggered May through September targets acute or window period infections technologic hurdles remain: PCR sensitivity sufficient, but... parasitemia low compared to viral infections requires whole blood limited volume for testing considerations of concentration techniques
Summary Babesia spp. pose a significant blood safety risk phylogeny and epidemiology increasingly complex frequent transmission to recipients and associated deaths suggests a need to act limited options available to mitigate risk cost/benefit issues relevant ultimately need licensed automated testing