babesia spp. - emerging transfusion dilemmas dr leiby - ipfa
TRANSCRIPT
Holland Laboratory
David A. Leiby, PhD
Transmissible Diseases Department American Red Cross Holland Laboratory Department of Microbiology and Tropical Medicine George Washington University
Babesia spp. – Emerging Transfusion Dilemmas
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 19th century
initially designated parasite as Heamatococcus bovis
unable to decipher transmission of the agent
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
Establishing Tick-Borne Transmission
Earle, DP. Trans Am Clin Climatol Assoc 1989;100:132-141.
Smith & Kilbourne, 1893
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
B. microti B. divergens B. duncani MO-1
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
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)
Spatial cluster 1 Spatial cluster 2
Seroprevalence/10,000 donations with spatial clusters
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
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
Persistent High Ab Titer = Chronic Carrier
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
Subject #03-0367*
Year Donors Tested
IFA Positive
(%)
PCR Tested
PCR Positive (%)
Lookbacks Positive
1999 3669 30 (0.8%) 19 10 (52.6%) 5/17
2000 2681 28 (1.0%) 18 9 (50.0%)
2001 2162 30 (1.4%) 25 1 (4.0%) 3/13
2002 2230 18 (0.8%) 14 2 (14.3%)
2003 1989 34 (1.7%) 20 2 (10.0%) 0/21
2004 2864 43 (1.5%) 33 1 (3.0%)
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
Babesia Transmission to Blood Recipients
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 4oC 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
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
Recipient Data
Tonnetti et al., Transfusion 2009;49:2557-2563
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
Donor Data
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
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
B. microti B. duncani
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