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Planning for the Future What’s coming for CBS? Resident Seminar May 29, 2009. Dr. Margaret Fearon Executive Medical Director, Medical Microbiology, Canadian Blood Services. Risk Assessment – What Can Blood Supplier Do?. Can high risk donors be excluded? Is there a screening test? - PowerPoint PPT Presentation
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Planning for the FutureWhat’s coming for CBS?
Resident SeminarMay 29, 2009
Dr. Margaret FearonExecutive Medical Director, Medical Microbiology,
Canadian Blood Services
2
Risk Assessment – What Can Blood Supplier Do?
• Can high risk donors be excluded?
• Is there a screening test?
• Effect of leukoreduction (removal of white cells).
• Assess impact of measures on blood supply.
3
Current Pathogens of Concern for Blood Operators
• Chagas Disease - protozoan• Babesiosis - protozoan • vCJD (variant Creutzfeld Jacob Disease) – prion• Influenza - virus• Malaria - protozoan • Ehrlichiosis – bacteria• HHV8 - virus• Dengue - virus
4
Chagas DiseaseTrypanosoma cruzi
Protozoan flagellate Trypomastigotes (blood) Extracellular (not removed by
leucoreduction) Amastigotes multiply in smooth
muscle tissue – heart, gut
Amastigote in heart muscle
Trypomastigotes in blood
5
Where is Chagas Disease Found?
Most of South America Central America Parts of Mexico
18 million people infected 1-2 million in large, non-endemic areas (Sao Paulo, Rio, Buenos Aires)
100,000 in the U.S. (?)
6From CDC
7
WHO/TDR
Reduvid Bug – aka ‘Kissing Bug’
8WHO/TDR
926
10
Stages of Chagas Disease• Acute stage: Immediate reaction to infection
– Only occurs in about 1% of people infected – Swelling of the eye, tiredness, fever, rash, loss of appetite– Can be fatal for infants and very young children– Severe in immunocompromised recipients (HIV/AIDS,
transplants)– Responds to Nifurtimox or Benzonidazole
• Chronic: 10 to 20 years after infection– Enlarged heart, arrythmias, cardiac failure (20-30%) or
digestive tract – megacolon, megaesophagus (9-14%) – Chronic encephalitis– 40-50% parasitemic with no symptomatic disease
11
WHO/TDR
Cardiomegaly in Chronic Chagas Disease
12
Reported cases of T. cruzitransmission via transfusion in the
U.S. and Canada
• 19871987 California via Mexican donor• 19891989 New York City via Bolivian donor• 19891989 Manitoba via Paraguayan donor• 19931993 Houston via unknown donor• 19991999 Miami via Chilean donor• 20002000 Manitoba via German/Paraguayan donor• 20022002 Rhode Island via Bolivian donor
– *5 cases – platelet transfusion, others unknown
Reference Source: Dr. D. Leiby, ARC
13
Continental U.S. Map: Cumulative RIPA Positives (January 2007 to present) (updated 5/21/09)
14
CBS Response To Chagas Disease Phase 1 - Risk Questions added to the Record of
Donation Feb.9, 2009
Questions:• 1. Were you born in Mexico, Central America, or South America?
• 2. Was your mother or grandmother born in Mexico, Central America, or South America? (If the answer is yes, the nurse would determine if it was the mother or maternal grandmother, leading to Chagas' risk, or the paternal grandmother, with no Chagas' risk)
• 3. Have you spent 6 months or more at any one time in Mexico, Central America, or South America?
Outcome for Donors • Platelets and transfusible plasma will not be made from donors who answer
‘yes’ to any of the risk questions.
15
CBS Response to Chagas DiseasePhase 2 - Donor Testing - Spring 2010
• Implement donor testing as a mandatory screening test for those donors answering yes to risk questions.
• Testing performed in Toronto Donor Testing Lab – batched.• Repeat reactives (RR) will be tested by immunoblot (confirmatory assay)
at National Testing Lab in Ottawa.
• Donors permanently deferred based on a RR test.• All manufactured components destroyed based on RR result.• Lookback performed on all confirmed positive donors.• Risk questions retained on RD – platelets will not be made from donors
who answer yes to risk questions even if they test negative (issue with timing).
16
Variant CJD (vCJD)
• Prion – transmissible protein – With aberrant folding– Transmitted by consumption of
BSE (bovine spongiform encephalopathy) contaminated beef
• Neurologic damage due to accumulation of abnormal protein
• Clinical – progressive, fatal neurodegenerative disease
17
VARIANT CREUTZFELDT-JAKOB DISEASE CURRENT DATA (FEBRUARY 2009) European and Allied Countries Study Group of CJD (EUROCJD/NEUROCJD)
COUNTRY
TOTAL NUMBER OF PRIMARY CASES (NUMBER ALIVE)
TOTAL NUMBER OF SECONDARY CASES: BLOOD TRANSFUSION (NUMBER ALIVE)
CUMULATIVE RESIDENCE IN UK > 6 MONTHS DURING PERIOD 1980-
1996
UK 165 (4) 3 (0) 168
France 23 (0) - 1
Republic of Ireland
4 (0) - 2
Italy 1 (0) - 0
USA 3† (0) - 2
Canada 1 (0) - 1
Saudi Arabia 1 (1) - 0
Japan 1* (0) - 0
Netherlands 3 (0) - 0
Portugal 2 (0) - 0
Spain 5 (0) - 0
† the third US patient with vCJD was born and raised in Saudi Arabia and has lived permanently in the United States since late 2005. According to the US case-report, the patient was most likely infected as a child when living in Saudi Arabia.*the case from Japan had resided in the UK for 24 days in the period 1980-1996.
*the case from Japan had resided in the UK for 24 days in the period 1980-1996.
18
vCJD
• Four cases of probable transfusion transmission in U.K. All transfused non-leukoreduced RBCs 1996-1999 – Case 1 received blood in 1997, died 2003, vCJD (6 yrs post
transfusion). Donor symptomatic with vCJD 3 yrs after donation.– Case 2 received blood in 1999, died 2004, unrelated causes. Donor
developed symptoms 18 mo. post donation.– Case 3 developed vCJD 6 yrs post transfusion. Transfused 1998. Donor
symptomatic 20 mo. post donation. Reported 2006– Case 4 received blood 8 yrs prior to becoming symptomatic. Same
donor as case #3. Reported Jan.07.
19
Case of vCJD in Plasma Product Recipient (UK)
• 70 yr. old male haemophiliac• Died early 2009 of unrelated condition, no symptoms of
vCJD• vCJD prion protein identified in spleen at autopsy• Treated with UK sourced clotting factors prior to 1999,
including one batch of Factor VIII manufactured using plasma from a donor who went on to
develop vCJD 6 months after donating.• Patient had other risk factors, including receipt of RBCs
and beef consumption.
20
Current vCJD Donor Deferral Policy at CBS
• > 3 mo. (cumulatively) in UK (England, N. Ireland, Scotland, Wales, Isle of Man or Channel Is.) or France from Jan. 1, 1980-Dec.31, 1996.
• >5 yrs. (cumulatively) in Western Europe (Germany, Italy, Netherlands, Switzerland, Austria, Belgium, Spain, Republic of Ireland, Portugal, Denmark, Luxembourg, Liechtenstein) since Jan. 1, 1980.
• Received a blood transfusion or blood product in the UK, France or Western Europe since Jan. 1, 1980.
21
Donor Testing
Donor Base of 3 M
True Positive300
False Negatives3
True Negatives2.97 M
False Positive30,000
Assuming that a donor screening test would have sensitivity and specificity characteristics of a typical donor screening test (99% specificity).
Several assays, including one from a Canadian company, Amorfix are urently under evaluation in the UK.
22
Prion Removal from Blood• Two companies have prion reduction filters in the
marketplace.• Pall: Prion filter with CE mark
– underwent testing at NBS using a hamster-adapted scrapie strain inoculated into human blood and transfused to hamsters
– Of 418 animals receiving filtered prion infected blood, 3 developed symptoms – therefore filter failed this evaluation.
• MacoPharma and PRDT, Inc. – filter that has just received a CE mark. – Currently in safety trials Ireland
• At the present time, there are no data outside of company development work to indicate that a rigorous prion reduction filter is available.
23
BabesiosisProtozoan parasites
Babesia microti, duncani,
http://www.ent.iastate.edu/imagegallery/ticks/deertick.html
24
Epidemiology
• Sporadic cases in Europe and Asia• U.S. Cases reported in:
– Connecticut– Rhode Is.– New York State– California– Washington State– Mississippi– Kentucky– Minnesota– Wisconsin
25
Clinical• Most infections asymptomatic or unrecognized• Incubation1-6wks.(9 post transfusion)
– Flu like symptoms– Severe: hemolytic anemia, thrombocytopenia, renal
failure, ARDS
• Overall mortality~5% (higher if at-risk)– i.e. immunocompromised, asplenics, v. young and
old, co-infection with other tick-borne diseases
• Treatment– Clindamycin + quinine x 7 d– Atovoquone + azithromycin
• Asymptomatic carrier state for months – years– up to 50% of seropositive cases may be parasitemic
26
Transfusion Transmitted Babesiosis
• >70 cases reported since 1979, most US
• 1 Canadian report, 1999– 53 yr old female– intestinal tumour resected– Received 5 units RBC Nov 1998-Feb
1999– April 1999: fever, anemia, hepatitis– Smear initially interpreted as P.
falciparum– 1 donor reported camping in Cape Cod
prior summer• Smear and PCR positive for B. microti
Extracellular and intra-
erythrocytic forms,
one of which is vacuolated.
27
Next Steps
• Better characterize donor risk of Babesiosis– Seroprevalence surveys– tick surveys (Ixodes species and Babesia prevalence)
• Assess donor risk of exposure– Specificity difficult because:
• Exposure common in endemic areas• Endemic areas are changing with climate and ecology change• Donors and blood move around
• Develop sensitive, specific laboratory donor screening assays – Selective vs universal donor screening?– Routine vs periodic or seasonal screening?– Serologic vs nucleic acid testing(NAT)?
28
INFLUENZA A(H1N1) SWINE
29
Source: Nature Medicine 1998; 4:1122-3.
30
H1
H2
H3
H4
H5
H6
H7
H8
H9H10
H11
H12
H13
H14
H15
H16
N1
N2
N3
N4
N5
N6
N7
N8
N9
30
Influenza A HA and NA Subtypes
Other Animals
Other Animals
Other Animals
Other Animals
Other Animals
Other Animals
31
Seasonal Influenza Transmission Routes
• Transmission of influenza viruses– Direct contact with infected person (hand-
shake)– Droplets from coughing or sneezing– Transmission from objects (fomites)
possible– Infectious 1 day before and up to 7 days
after becoming sick
31
U.S. Centers for Disease Control and Prevention
32
Pandemic Influenza Phases
33
The World Health Organization
34
35
FluWatch April 26 – May 2
36
FluWatch May 3 - 9
37
Influenza strain characterization, Canada, cumulative, 2008-2009 influenza season by the Respiratory Viruses Section at the National Microbiology Laboratory
[N=1044]
38
The Public Health Agency of CanadaInfluenza A(H1N1) Epidemic Curve May 25, 2009
39
Pandemic PhasesCBS has identified 4 levels of alert escalation in line with the World Health Organization phases. The following chart shows the alignment.
CANADIAN BLOOD SERVICES WORLD HEALTH ORGANIZATION (WHO)
Pandemic Plan Activity Phases
Pandemic Escalation
Levels
Pandemic Escalation Categories
Colour Code
ActionWHO
Pandemic Alert Phase
Meaning
Interpandemic 1 Routine Green Business as usual 1 Low risk of human cases
Interpandemic 1 Routine Green Business as usual 2 Higher risk of human cases
Interpandemic 1 Routine Green Business as usual 3No or very limited human-
to-human transmission
Pandemic Alert 2 Stand by Amber
Risk of potential impact on CBS
increases. Escalate readiness.
4
Evidence of increased human-to-human
transmission in small, localized clusters
Pandemic Alert 2 Stand by Amber
Risk of potential impact on CBS
increases. Escalate readiness.
5
Evidence of significant human-to-human
transmission in larger but localized clusters
Pandemic 3 Active Red
National response to pandemic influenza is
required
6Efficient and sustained
human-to-human transmission
Post-Pandemic 4Transition to
Routine Operations
Black
CBS disengages from pandemic
state of emergency and resumes
business as usual
40
CBS Influenza Pandemic Plan
Key Strategic Responses – department level (in order of preferred implementation):
1. Suspend non-critical business activities.
2. Re-assign departmental staff from performing non-critical business activities to more critical business activities, as required.
3. Where possible, offer surplus staff to other managers who might be experiencing more significant staffing difficulties.
4. Where possible, transfer work to another location that is not as
significantly impacted.
41
Maximizing Blood Inventories
It will be necessary and critical to implement temporary
changes to established policies and practices so as to:
1. Ensure most effective use of reduced staffing;
2. Maximize donor availability to fill collection capacity;
3. Maximize immediate access to and use of blood inventories.
Risk of the changes will need to be balanced against the
risk of depleted blood inventories.
42
Modelled Pandemic Impacts on RBC Inventory Levels
Modelled RBC Inventory Levels Assuming 17,000 Jump-off
0
5,000
10,000
15,000
20,000
25,000
30,000
Wee
k -8
Wee
k -6
Wee
k -4
Wee
k -2
Wee
k 1
Wee
k 3
Wee
k 5
Wee
k 7
Wee
k 9
Wee
k 11
Wee
k 13
Wee
k 15
Wee
k 17
Wee
k 19
Wee
k 21
Wee
k 23
Wee
k 25
Wee
k 27
Wee
k 29
35% Model with 40% Offset 35% Model with no Offset
35% Model with 20% Deterioration Original 35% Model with 40% Offset
Ramp Up Outbreak Recovery
43
CBS Response to A(H1N1)• Convened regular meetings of the IBEPAG (International Blood
Emergency Planning Action Group) to discuss blood operators’ responses.• Developed key messages and Question & Answer material for:
– Internal staff communication; and– External messaging(Focus on hand hygiene, ‘cover your cough’, good infection control as well
as provision of up to date information on outbreak)• Provided EMT with status updates and convened National
Emergency Response Team (NERT) and Local teams (LERTs) to manage the CBS response.
• Assessed current donor screening criteria to conclude that sufficient criteria are in place to appropriately screen-out potentially infected donors
• Continue to monitor global outbreak information to guide CBS decision making.
• Will be reviewing and revising pandemic flu plans based on ‘lessons learned’.