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Weather Forecasting Approach of Transfusion Services to New Pathogen ( Emerging Infectious Agents )

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Title: Weather Forecasting Approach of Transfusion Services to New Pathogen ( Emerging Infectious Agents )


1
Weather
Forecasting Approach
of Transfusion Services to
New Pathogen ( Emerging Infectious Agents )
  • Dr. R. N. Makroo
  • Director Sr.Consultant
  • Dept. of Transfusion Medicine,Molecular Biology
    Transplant Immunology
  • Indraprstha Apollo Hospitals

2
Introduction
  • Over the past 10 to 15 years the leading causes
    of allogeneic blood transfusion-related morbidity
    and mortality have shifted from being mainly due
    to transfusion-transmitted infections (TTIs) to
    the non-infectious events associated with blood
    transfusions

3
Introduction
  • Nonetheless, despite many advances in the
    prevention of TTIs, TTIs continue to be
    associated with on-going morbidity and mortality.
  • This is due to the emergence of new pathogens
    (or re-emergence of known pathogens) associated
    with TTIs.

4
Components of Blood Safety
  • National and local incidence/prevalence
  • Criteria/Standards/
  • Guide-lines
  • Selection of donor population
  • Donor questioning
  • Laboratory testing
  • Product handling
  • Record keeping
  • cGMP/Quality

5
Outline
  • Status of blood donors
  • Current status of testing risks
  • Emerging infections in Developed Vs Developing
    countries
  • Background
  • Approach
  • Examples
  • VIRUSES, BACTERIAS, PRIONS,PARASITES, TICK BORN
    etc.

6
Emerging Infections
Clinically distinct conditions whose frequency
in humans has increased over the past two
decades
7
Factors Contributing to Emergence of
Infectious Disease
  • Human demographics and behavior
  • Technology and industry
  • Economic development and land use
  • International travel and commerce
  • Concept of global village
  • Microbial adaptation and change
  • Breakdown of public health measures

8
Speed of Global Travel in Relation to World
Population Growth
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From Murphy and Nathanson. Semin. Virol. 5, 87,
1994
9
Emerging Infections in Western World
  • New Agent
  • Expanding Range
  • Imported
  • Re-emergent
  • Newly recognized
  • Patient changes
  • BSE/vCJD
  • Babesia/Ehrlichia
  • Chagas disease, WNV
  • Malaria
  • HHV-6, 8, TTV, SENV.
  • CMV, B19?

NAT is performed on essentially all blood and
plasma donations in the United States The
decrease in risk over time for HIV, HCV, and HBV
has been truly dramatic.
10
Concern High, Action Favored
HBV
vCJD
HCV
HIV
CJD
WNV
T.cruzi
Bacteria
Babesia
Ebola etc
HHV 8
Leishmania
B19
HAV
HHV 6
Malaria
Lyme
Ehrlichia
HGV, etc
RMSF
Chlamydia, Leptospira Bartonella, etc
Benefit High Action Favored
11
Blood is much safer, but is it safe enough?
All volunteer donors
HBsAg test
25
20
15
AIDS high-risk exclusions
Recipients Infected
Anti-HIV test
10
ALT/HBcAb tests
Anti-HCV test
Improved HCV tests
5
NAT Implementation
0
1965
1970
1975
1980
1985
1990
1995
2000
Tobler and Busch, Clin Chem 1997.
Year of Transfusion
12
(No Transcript)
13
Infections in India our problems
  • HIV, HCV, HBV AND MALARIA Major problem to
    Blood safety
  • NAT not Implemented to reduce the incidence


HIV, HCV AND HBV
Action Favored
New Viruses
14
IS REALLY INDIA AT THE TOP IN BLOOD SAFETY ???
  • NO
  • Very little concept of
    regular repeat V.B.D
  • Absence of Universal Hepatitis B core
    antibody Screening
  • WITH NO NAT
  • No Uniformity in the Blood Transfusion
    Services
  • ITS REALLY A LONG WAY TO GO
  • AND ITS A STEEP HILL TO CLIMB

15
Indian Scenario
  • BTS in India is mainly hospital based
  • Blood Banking is governed by Drugs Cosmetic Act
  • 2609 licensed blood banks under different??
    control
  • Gap in demand and supply of blood
  • Majority of blood donors are still replacement
    donors
  • Voluntary donors constitute only 65 (NACO 2011)
  • Majority of voluntary blood donors are first time
    donors
  • Little concept of regular repeat voluntary blood
    donation

16
Challenges of Blood Screening in India
  • Population 1.2 billion includes 2.5 million with
    HIV, 15million with HCV, and 43 million with HBV
  • High blood donor seroprevalence of 0.3,0.7,
    and 1.4 for anti- HIV-1, anti-HCV, and HBsAg,
    respectively increases transfusion transmission
    risk of these viruses
  • High percentage ( 35) of replacement donors
    compared to volunteer donors
  • 2609 ( 36) government , (28)private hospitals,
    (14) NGO (21)Stand alone private blood
    banks, many of which have poorly regulated
    practices, collect about 8 million donations
    annually.
  • Currently nucleic acid testing (NAT) for
    screening is not mandatory which would need to
    be adapted to our low volume setting

17
Threat to Safety of Blood Supply
  • Current immunoassay blood screening tests detect
    virus-induced antibodies or viral antigens, not
    the virus itself Window Period donations
  • Window period between initial infection and
    detectable seroconversion
  • Chronic carrier state in asymptomatic donor -
    test negative on antibody screen
  • Atypical genetic variants of viruses
  • Laboratory errors (very low zero-0.05, further
    reduction by gt1 assays)

18
Window Period
Infection
HIV Ab Negative
HBsAg Negative
Window Period
HCV Ab Negative
Detection by Serology markers
19
Closing the gap!-To enhance blood safety
  • Implementation of new tests to narrow down the
    window period
  • Combining gt1 assays - 2 assays complement each
    other and decrease FP and FN results
  • Increasing regular repeat voluntary donations
    (lower TTI incidence)

20
Why ID-NAT is preferred over Minipool?
  • High prevalence countries Greater number of
    reactives
  • Low Regular Repeat Voluntary Donors Higher
    percentage of reactives
  • Pooling results in a dilution of viremic samples
    proportionate to the pool size
  • MP-Reduces sensitivity. Release of infected
    units.
  • MP requires additional process time, equipment,
    manpower, lab space environment for pooling and
    resolution of positive pool.
  • High prevalence countries have higher number of
    pools reactive. Delayed release of negative blood
    units from a positive pool. 1-2 days delay.
  • Higher contamination and error chance.

21
In Asia Why ID NAT
  • Dr. J. P. Allain from Cambridge University-
    Global Expert on Hepatitis B in Blood
    Transfusions quotes
  • Study with 143 samples from South East Asia
    showed
  • 70.7 of these would be missed in pools of 6 and
    87.5 in pools of 10 assuming a sensitivity of 5
    IU per ml
  • 37 of the donors had less than 5 IU/ml, and
    over 40 had between 5 and 30 IU/mL
  • Additionally in India the predominant HBV is of
    genotype D which is characterized by low viral
    load with 10 having undetectable HBV DNA.

22
Why Nucleic Acid Testing? Reduction of Window
Period
Busch MP et al. Transfusion 200545254-264,
Assal A et al. Transfusion 200949289-300,
Weusten J et al, Transfusion 201151203-15
23
HIV-1 Minipool NAT Failures
Dwyre et al, Vox Sang 2011
24
HBV detection superiority with ID-NAT
Dwyre et al, Vox Sang 2011
25
TMA HCV superiority sensitivity
Sarrazin et al, Journal of Clinical Virology 2002
Comandor et al, Am J Gastroenterology 2001
26
HCV Reactivity (April, 2006 March 2012)
Profile of 7 HCV NAT Yields Total tested
117,622 Need for NAT and IDT NAT
  • 0.39 (458) Sero prevalence for anti-HCV.
  • 0.17 (191) concordant Sero and NAT positives
  • 7 HCV NAT only yields1 , 4 Co-infections HCV
    HBV (ELISA HBV only)
  • 267 Serology yields - High false positivity of
    HCV ab tests2 - Need for NAT

S/N Ultrio Discrim Assay Reactive Serology Viral Load IU/ml
1 HCV Non Reactive 56
2 HCV Non Reactive 52
3 HCV HBsAg 97
4 HCV Anti HBc, Total 58
5 HCV Anti HBc, total 62
6 HCV Anti HBc, Total 99
7 HCV Non Reactive 53
  • The low viral load of 52-99 IU/mL indicates the
    requirement of ID-NAT testing

1. Makroo RN,Chowdhry M,Minimole, Rosamma NL
Thakur U. Six years Experience on Impact of
Individual Donor Nucleic Acid Testing for
Hepatitis C Viral RNA at a Tertiary Care Hospital
of North India. 65th Annual AABB meeting Oct 6-9
Boston MA 2. Raghuraman et al. Occurrence of
False Positives during Testing for Antibodies to
Hepatitis C Virus among Volunteer Blood Donors in
India, J .Clin. Microbiol. 2003 411788-1790.
27
HBV Reactivity (April, 2006 March 2012)
Total tested 94,247 recalculate numbers Profile
of HBsAg, anti HBc and HBV DNA1
HBsAg ELISA Anti HBc ELISA Number Percentage HBV DNA- Percentage (Number)
Positive Non reactive 156 0.16
Positive Reactive 978 1.03
Negative Reactive 8660 9.19 0.15 (13)
Negative Reactive 0.007(9) Occult NAT yields
Negative Non Reactive 0.006 (8) WP NAT yields
Positive ?? 0.75 (887) Serology NAT concordants
Positive ?? 0.37 ( 442) Sero yields
  • Presence of HBV DNA is indicative of infectivity
  • 99.85 of anti HBc reactive are negative by
    Procleix Ultrio HBV assay
  • Very high attrition of donations if excluded for
    anti HBc at 9.19 positivity

28
ID-NAT YIELDS
RN Makroo et al. Indian J Med Res 127, February
2008, pp 140-147
Multicenter evaluation of individual donor
nucleic acid testing (NAT) for simultaneous
detection of human immunodeficiency virus -1
hepatitis B C viruses in Indian blood donors
29
ID NAT Yield 1 in 1500
67 in 100,000 donations
6700 infected donors per 10 million donations
Each donor infects 3 patients
6700 X 3
app. 20000 infections per 10 million donations
Annual cost of medical management 1.5-2.5 lacs/pt
app. INR 400 crores annual expenditure
Cost of liver transplant 20-25 lacs/pt
10,000/month
If 2000 patients undergo LT/ yr
app. INR 500 crores annual expenditure
app. Cost for doing 10 million ID-NAT 800 x
10 million INR 800 crores
30
Good quality costs
Poor quality costs more
31
NAT and Hepatitis
  • Most transfusion-transmitted infections are
    caused by blood donated during the early
    sero-negative window period, and for HBV also
    during Occult status.
  • Direct detection of viral nucleic acids by using
    the NAT technologies significantly improves the
    blood safety by shortening the window period and
    detecting occult cases.
  • Since 1999, all developed and increasing number
    of developing countries around the world have
    adopted routine NAT blood screening. Countries
    have moved to ID-NAT after including HBV.
  • NAT on individual donations (ID NAT) provide the
    highest level of safety to the blood supply.

32
HTLV-1 2
  • HTLV-I identified in 1978 in a Japanese patient.
  • Causes adult T-cell leukemia and lymphoma (ATL)
    and tropical spastic paraparesis (TSP) also known
    as HTLV-I-associated myelopathy or HAM.
  • Prevalent globally but is endemic in Japan, the
    Caribbean, South
  • America, and West and Central Africa, where
    infection rates are above 1.
  • HTLV-II identified in 1982 in a patient with
    hairy-cell leukemia
  • HTLV-II is found in American Indian populations
    and in some populations of intravenous drug users
  • The overall incidence in first-time donors in the
    United States is around 40 per 100,000. In repeat
    donors a rate of approximately 1.6 per 100,000
    person years was identified from 1991 to 1996
  • In India its prevalence was found to be 0.18 and
    was concluded that prevalence of HTLV-I/II
    carriers in India seems to be negligible and is
    not a major public health hazard. Hence, routine
    screening of Indian blood donors for antibody to
    HTLV-I/II is not warranted due to its low
    prevalence.

Rossis principle of Transfusion Medicine. 4th Ed
Kumar H, Gupta PK. Is seroprevalence of
HTLV-I/II among blood donors in India relevant?
Indian J Pathol Microbiol. 2006 Oct49(4)532-4.
33
Malaria
  • Caused by plasmodium species
  • P. Falciparum IP is 12 days, 40-60 malaria
    cases worldwide, gt95 of all malarial deaths
  • P. vivax 30-40 malaria cases, rarely fatal
  • P. ovale West Afica
  • Others P. malariae and P. knowlesi
  • Transmitted by female anopheles mousquito
  • Transmitted by cellular blood components whole
    blood or PRC or by components contaminated with
    red cells
  • At 2-8 o C P falciparum can survive for 2-3
    weeks
  • Post transfusion malaria (PTM) severe disease in
    pregnant women and immuno deficient individuals

34
Malaria
  • Detection
  • Microscopic blood films gold standard
  • Macroscopic
  • Tests for malaria Ab EIA, indirect
    immunofluoresence, western blot
  • Tests for malaria Ag RIA, EIA
  • Tests for metabolic products LDH ( all species)
    and HRP-2 ( falciparum)- method of choice for
    screening of blood donors
  • Other nucleic acid based tests and
    immunofluorscence for detection of plasmodia
    within the erythrocytes
  • Prevalence of Malaria at our centre in 2011
    0.019

35
Cytomegalovirus
  • It is a herpes virus sub-family
    betaherpesvirinae
  • Incubation period 4-8 weeks
  • Also known as HHV-5
  • CMV can manifest itself in many organs.
  • Therefore, CMV is a major problem in
    immuno-suppressed patients requiring transfusion
    therapy.
  • 95 of blood donors in India are sero positive
    for CMV

36
95 of blood donors in India are sero positive
for CMV
37
Cytomegalovirus
  • Patients who should receive components that are
    selected or processed to minimize the risk of CMV
    infectivity include the following
  • Transplant recipients ( CMV negative)
  • Patients with severe immunodeficiency
  • Fetus (intrauterine transfusion)
  • CMV-negative pregnant females
  • Low birth weight premature infants and neonates
  • It is essential for all blood banks to maintain a
    list of CMV negative donors
  • Leukoreduced blood (lt5 X 106 Leukocytes) CMV
    negative blood

38
Cytomegalovirus
  • Donor testing
  • ELISA ( IgM or IgG or IgM IgG )
  • Complement fixation test
  • Heamagglutination
  • Western blot
  • PCR based assays

Rossis principles of Transfusion Medicine, 4th ed
39
Trypanosomiasis (Chagas disease)
  • Causative Agent Trypanosoma cruzi
  • Transmitted by triatomines or reduviid bugs
    (kissing bugs)
  • Acute phase lasts 4 to 6 weeks, characterized by
    mild symptoms such as fever, malaise, and edema
    of the face, as well as lymphadenopathy and
    hepatosplenomegaly.
  • The fatality rate in the acute phase is usually
    less than 5.
  • Up to decades later, 15 to 30 of carriers will
    develop serious sequelae involving the heart and
    gastrointestinal tract (mega-colon and
    mega-esophagus).
  • Chagas disease kills an estimated 13,000 people
    annually, mostly from cardiac complications.
    Barrett MP, Burchmore RJS, Stich A, et al. The
    trypanosomiases. Lancet 20033621469-80
  • In India infections caused by T. evansi have been
    reported from Maharastra India. Joshi PP et al
    Am. J. Trop. Med. Hyg., 73(3), 2005, pp. 491495
  • Screening test ELISA
  • Confirmatory testing RIPA (not FDA approved)
  • Other methods donor exclusion and pathogen
    inactivation

40
T. Cruzi in blood units
  • Are platelets of greatest risk?
  • few platelet units in look-backs
  • transfusion cases almost all involved platelets
  • survival and localization studies

whole unit lt 7 days platelets lt 4 days red
cells lt 2 days plasma none
41
Transfusion Transmitted Leptospirosis
  • Causative agent Leptospira interrogans
  • Incubation period 2-21 days
  • Endemic in Maharashtra, West Bengal, Orissa,
    Gujarat, Tamil Nadu Andaman islands
  • Spreads by direct or indirect contact with urine
    of infected animals
  • Symptoms influenza like illness
  • 80 clear infection spontaneously, 10 suffer
    from complications while it is fatal in another
    10
  • Methods of detection
  • Dark field microscopy
  • culture
  • Detection of IgM antibody
  • PCR based assays

42
Transfusion Transmitted Leptospirosis
Results
Of 794 DFM positive samples, 155 were cultured on
liquid EMJH medium.
43
Brucellosis
  • Causative agent B. melitensis, B. suis and B.
    abortus
  • Zoonotic infection transmitted to humans
    primarily by consumption of unpasteurized milk
    and milk products
  • Common presenting symptom are fever, fatigue,
    malaise, chills, sweats, headaches, myalgia,
    arthralgia, and weight loss
  • Widespread in rural india
  • Transfusion transmitted brucellosis severe
    infection in immuno supressed, neonates and
    pregnant females
  • Diagnostic methods
  • Blood cultures
  • Antigen detection by ELISA
  • Antibody detection IgM and IgG
  • Agllutination Rose Bengal Plate agg. (RBPT )and
    standard tube agg test (SAT) for screening
    purposes

It is suggested that, in areas endemic for
brucellosis, blood donors should be questioned
about symptoms of brucellosis, and if suspected,
serological tests for brucellosis should be
indicated before blood transfusion. At the same
time, the prevalence of the disease among animals
should be reduced with effective animal disease
control programs. Akçakus M et al. Brucella
melitensis in blood cultures of two newborns due
to exchange transfusion.Turk J Pediatr. 2005
Jul-Sep47(3)272-4.
44
Creutzfeldt- Jakob disease (CJD)
  • It is transmissible spongiform encephalopathies
    (TSEs), comprise a spectrum of diseases in
    animals and humans.
  • In animals, these diseases include scrapie in
    sheep and goats, chronic wasting disease in deer
    and elk, and transmissible mink encephalopathy.
  • Bovine spongiform encephalopathy (BSE) was first
    described in cattle in the United Kingdom (UK)
  • In humans it causes fatal progressive dementia
    and motor disturbances
  • Iatrogenic transmission of sporadic CJD has
    occurred via neurosurgical instrumentation and
    electroencephalogram (EEG) electrodes, corneal
    and dura mater grafts, and cadaveric
    pituitary-derived growth and follicular
    stimulating hormones.
  • Blood transfusion results in Variant CJD (vCJD),
    first described in 1996.

National CJD Surveillance Unit. CJD statistics
Edinburgh, UK NCJDSU, 2008. Available at
http//www.cjd.ed.ac.uk/fi gures.htm (May 16,
2008).
45
Creutzfeldt- Jakob disease (CJD)
  • Pathogenesis
  • presence of abnormal prion protein (PrPTSE)
    within the central nervous system and also in the
    follicular dendritic cells of peripheral lymphoid
    tissues including tonsils, spleen, lymph nodes,
    and gut-associated lymphoid tissue
  • Donor screening methods
  • Permanent deferral of donors
  • family history of CJD
  • Recipients of growth hormone and FSH of human
    origin
  • Recipients of human dura matter and corneal
    grafts
  • Permanent residents of U.K.
  • Detection of PRPTSE peripheral blood
  • Immunoblotting with proteinase K digestion and
    gel electrophoresis has been enhanced using
    phosphotungstic acid precipitation and
    chemiluminescence
  • Capillary immunoelectrophoresis following
    proteinase K digestion and competitive antibody
    binding

46
Distribution of TSE Infectivity in Blood
Components
Plasma 25 - 30
Buffy Coat 35 - 45
RBC 20 - 25
47
Newer viruses Dengue
  • Dengue is one of the most serious mosquito borne
    viral disease of humans.
  • Transmitted by Aedes mosquito
  • Estimated number of Dengue cases per annum
    worldwide 50100 million
  • Estimated number of severe forms of the disease
    500.000 (0.5 a 1)
  • Dengue like illness date back to more than 200
    years ago
  • 1779-1780 in Asia, Africa and North America
  • Viral etiology established by the 1940s
  • Global pandemic in Southeast Asia after World War
    II

Historical background
48
Dengue the virus
  • There are 4 distinct serotypes DENV-1, DENV-2,
    DENV-3, DENV-4
  • Family Flaviviridae Genus Flavivirus
  • All serotypes produce a similar illness and
    induce a life-long immunity that is specific to
    the infecting serotype.
  • However, although the four serotypes are related,
    the humoral immune response does not provide
    cross protective immunity against each other.

Transmission by Blood Transfusion
  • In the 2001 one case of dengue transmission
    through bone marrow transplantation in Puerto
    Rico
  • In 2002 1 case transmitted by red blood cell
    transfusion were reported in Hong Kong.
  • In both cases, donors made their donation during
    the viremic period but 1 to 2 days before the
    onset of symptoms.
  • Later they developed classical dengue disease.

49
  • A 52-year-old, asymptomatic, repeat blood
    donor gave blood on July 15, 2007. An
    investigation of all recipients of his blood
    products was initiated after he informed the
    blood bank that he had had a fever the day after
    donation. The stored serum sample was positive
    for dengue virus type 2, as ascertained by means
    of a polymerase-chain-reaction (PCR) assay.
  • Tambyah et al. Dengue Hemorrhagic Fever
    Transmitted by Blood Transfusion N Engl J Med
    2008 3591526-1527
  • (National University of Singapore,
    Singapore 119074, Singapore)

Highly prevalent now
Prevalent from centuries
50
Is there any impact of Dengue Epidemic on
transfusion ?
  • Do not have a precise information on the
    percentage of individuals who is asymptomatic
    during a given epidemic.
  • Literature reports provide estimates from 30 to
    70 of asymptomatic individual at an epidemic.
  • Also largely unknown is the level and length of
    viremic period among asymptomatic individuals.
  • It is obvious that a short and low level viremia
    will have a moderate impact on the risk of dengue
    transmission by transfusion.
  • Therefore, The asymptomatic carriers may act as a
    source of platelets to the symptomatic patients !

51
West Nile Virus
  • Causative agent a flavivirus, first recognized
    in 1937
  • Wide distribution in Africa, Europe, Asia,
    Australia, and, in the past decade, in Northern
    America.
  • WNV mainly infects birds and is normally
    transmitted by mosquito (Aedes)
  • The incubation period is between 3 and 15 days in
    humans
  • 80 of infections being asymptomatic or with a
    mild flu-like illness. In rare cases (fewer than
    1 of those infected), a more severe disease
    results and fatal encephalitis can occur.
  • Asking donors about pre-donation headache and
    fever was found to have no effect on blood
    safety. (Orton SL et al. Self-reported symptoms
    associated with West Nile virus infection in
    RNA-positive blood donors.Transfusion
    200646272-7).
  • The risk of transfusion transmission is
    associated with a period of viremia occurring
    around 3 days after infection and lasting around
    a week.
  • Since July 2003, the US and Canadian blood
    supply has been screened using WNV NAT
  • Both minipool and ID-NAT assays are available.

52
TT virus, SEN V, GBV-C/HGV
  • TT Virus
  • DNA unenveloped , non hepatotropic virus
  • named for the patient from whom it was first
    isolated in Japan
  • Genus Circoviridae.
  • Transmitted by orofecal and transfusion route
  • Transfusion route is not significant in TTV
    epidemiology
  • SEN V
  • SENV is not 1 virus but rather 8 diverse strains
  • 2 of these strains (SENV-D and SENV-H) causes
    of transfusion-associated non-AE hepatitis
  • SENV is clearly transmitted by Transfusion
  • Although SENV is clearly transmitted by
    transfusion, these data are insufficient to
    establish a causal relationship between SEN V and
    TAH
  • GBV-C/HGV
  • Enveloped RNA virus
  • Virus genome similar to HCV
  • Transmitted through blood transfusion
  • High Risk groups
  • IV drug abusers

53
Bacterial contamination of blood products
Popular organisms
RBC
Platelets
  • Y Enterocolitica
  • Pseudomonas
  • E. coli
  • Klebsiella
  • Proteus
  • Propionibacterium
  • Serratia sp
  • Coag neg staphylococcus
  • Staph aureus
  • streptococcus
  • Staph Epidermidis
  • Bacillus sp
  • Staph aureus
  • Micrococcus
  • Diphtheroids

Bacterial contamination of platelets is specially
problematic as they are stored at RT
54
Sources of contamination
  • Donor bacteremia
  • Phlebotomy core
  • Skin surface contaminants
  • Containers and disposables
  • Environment

55
Comparison of Residual Risks
1100
Transmission risk, per unit
HIV
11000
Bacterial Contamination (platelets)
HBV
110 000
HCV
Clinical Sepsis (platelets)
1100 000
Septic Fatalities (platelets)
11 000 000
1996
1994
1992
1990
1988
1986
1984
1998
2000
2002
Updated from Goodnough LT e t al. NEJM
1999341126-7
56
(No Transcript)
57
  • Donor deferral
  • Skin decontamination before phlebotomy
  • Diversion of first 15 ml of blood
  • Closed system of component preparation
  • Apheresis products

58
  • Storage time
  • 24 hour hold
  • Storage temperature
  • Cool liquid stored platelets
  • Frozen platelets

59
  • Visual inspection
  • Discoloration
  • Clumping
  • Loss of swirling
  • Biochemical parameters
  • Platelet pH
  • Glucose consumption
  • Limulus amebocyte lysate assay (yersinia
    endotoxin)
  • Microscopy
  • Gram stain
  • Acridine orange

60
  • Culture (gold standard)
  • BacT/Alert CO2 production
  • Pall BDS O2 production
  • Rapid tests
  • Verax PGD
  • Others
  • PCR
  • Chemiluminesence based universal bacterial rRNA
    probe

61
  • Pathogen reduction technology
  • Room temperature hold
  • Filtration

62
STRATEGIES TO PREVENT INFECTION
Tracebility Hemovigilance
  • Indications for transfusion

Storage Pathogen inactivation Screening tests
Processing quality control
Donor eligibility
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Summary
  • Emerging infections may impact blood safety
  • Continuing, structured review of field needed
  • Risk assessment is performed as required
  • Selected agents are further evaluated in the
    field and the laboratory
  • Interventions testing, interview, call-back
  • Partnerships with industry, public health agencies

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The Road Ahead
  • Commitment of blood banking community to provide
    safe blood.
  • Active involvement of health economists keeping
    in mind that good quality costs.

65
BLOOD IS A PRICELESS GIFT.....
  • .....but the final product costs !!

66
THANK YOU
Lets keep these unexpected passengers out
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