Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood...

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Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin, Memorial Blood Centers Duluth TAM

Transcript of Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood...

Page 1: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Black Bugs Blood:West Nile Virus & the Blood Supply

Infectious Transfusion Risks, Screening Blood donations for WNV

and other icky things

Jed Gorlin, Memorial Blood Centers Duluth TAM 11/04

Page 2: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Risks of Transmission

• Infectious Risks– Viral

– Bacterial

– Protozoa

– Ricketsia

– Other• ?Prion

• Non-infectious risks– Transfusion Reaction

– Metabolic

– Cardiac Overload

– Dilutional Coagulopathy

– TAGVHD

– Alloimmunization

Page 3: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Transfusion Safety

• Product Safety– Donor Recruitment

– Donor history screening

– Donor Testing

– Manufacturing cGMP

• Transfusion Safety– Patient blood sample

– Med indication for Tx.

– Special Tx needs

– Select right unit

– Issue to floor

– administration

– monitoring & evaluation of reaction

Page 4: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

101102103104 100105106107108

HIV

HCVHBV

Mis-Transfusion

TRALI

TA-GVHD

Under transfusion

Cardiac

Paling Risk Scale for Major Transfusion Hazards

Metabolic risk in neonates

Bacteria

General anesthesia

Sunny Dzik, MD

Page 5: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Window period risk

• Why is there any residual risk? There is potential for transfusion transmission, if donors is drawn after acquiring the disease but before they make an antibody response.

• Time from infectivity to test reactivity

• Chance of transmission is a function of both incidence and length of window period.

Page 6: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

NAT screening (HCV/HIV/HBV)

• Two major testing platforms for HIV/HCV

• Roche-Pools of 24, separate tests for HCV, HIV. Advantage: automated detection, disadvantage, very manual sample prep

• Chiron-Gen Probe (TMA) Multiplex test– Pools of 16, automated sample prep, manual

detection. Requires extra round to resolve positive samples. More false positives

Page 7: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

MBC Experience

• After testing almost 2,000,000 samples, MBC has detected 1 HIV NAT window period case and 5 HCV NAT+/EIA negative samples.

• Almost 1,000,000 samples were tested for both HCV and HIV before a single NAT+/EIA - sample was found.

Page 8: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

U.S. NAT Program Yields

Program # HCVRate

# HIVRate

UBS

ABC-Roche

AIBC

ARC

US Total

16

23

2

29

70

1:294,926

1:239,630

1:236,937

1:331,828

1:275,830

2

1

0

1

4

1:2,359,409

1:2,581,512

0:473,874

1:9,623,012

1:3,759,451

Page 9: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

What Has NAT Testing Cost the US??

• Assume 13 million blood donations annually

• Assume an average cost/donation of $16

• Cost of HCV/HIV- NAT =

• $208,000,000/yr or $104M each

Page 10: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Cost/HCV-NAT positive donation:

• Average HCV-NAT pos. rate in US = 1:276,000 donations

• 13 million donations/yr collected

• 47 window case donations expected @ $104,000,000 total

• Cost/HCV-NAT positive donation detected = $>2,200,000/donation

Page 11: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Cost/HIV-NAT positive donation:

• Average HIV-NAT pos. rate in US = 1:3,760,000 donations

• 13 million donations/yr collected

• 3.5 window case donations expected @ $104,000,000 total

• Cost/HIV-NAT positive donation detected = > $28,000,000/donation

Page 12: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

200,000

Cost-effectiveness ($/YLE)

600,000

400,000

2,000,000

4,000,000

6,000,000

8,000,000

ALTTesting

p24 AgTesting

Anti-HBcTestingfor HIV

MP NATHIV+HCV

SD FPHCVLook-back

RhIg/HDN Prophy-

laxis

CABG(one

vessel)

HTN

Therapy

AnnualMammo-

gram

CardiacTrans-

plantation

Transfusion Safety Interventions

Commonly Accepted Medical Practices

PAD- CABG

MP=>SDNAT

Cost-Effectiveness Comparisons

Page 13: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Other Transfusable Parasitic

• Chagas– Trypanosoma cruzi Endemic: Central & So. America

– Infected reduviid (kissing) bug falls from thatched roof, defecates and inoculates skin

– May be under-recognized cause of heart failure

– Only 7 cases Tx transmission in US/Canada

– Screened for in Brazil and other LA countries

– ARC proposes to implement screening

– MBC to participate in Chagas trial ~1/05

Page 14: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

West Nile Virus: Background and Ecology

• First isolated in West Nile district, Uganda, 1937

• Commonly found in humans and birds and other vertebrates in Africa, Eastern Europe, West Asia, and the Middle East, but has not previously been documented in the Western Hemisphere

• Basic transmission cycle involves mosquitoes feeding on birds infected with the West Nile virus

• Infected mosquitoes then transmit West Nile virus to humans and animals when taking a blood meal

West Nile Virus: Background and Ecology

Page 15: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

The Japanese Encephalitis Serocomplexof the Family Flaviviridae

Page 16: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

1999 - 2002 Verified WNV Surveillance Results Reported to ArboNet

731919733266/927 + DC2001

44 + DC

11 + DC

4

States

11,450

63

25

Horses

593814,7903949/262 2002

515430521/22000

16?62/61999

MosquitoPools

BirdsHumans/Fatalities

Year

Page 17: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Date of Symptom Onset, West Nile VirusUnited States, 1999-2001

0

5

10

15

20

25

30

7/7

8/4

9/1

9/29

10/2

711

/24

12/2

3

Week ending

Nu

mb

er

of

ca

se

s

2001

2000

1999

Page 18: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Clinical Epidemiology

• Incubation period 3 - 14 days• ~80% of infections are asymptomatic• 20% develop “West Nile fever”• 1 in 150 develop meningoencephalitis

– Advanced age primary risk factor for severe neurological disease and death

Page 19: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Outcome of West Nile Virus Infection among Hospitalized Patients

• At discharge (NY and NJ, 2000)– More than half did not return to functional level– Only one-third fully ambulatory

• At one year (NYC 1999 patients)– Fatigue 67%, memory loss 50%, difficulty

walking 49%, muscle weakness 44%, depression 38%

Page 20: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Summer 2003

• Implemented WNV NAT screening 7/1/03

• Automated DNA extraction

• Pool size 6-dedicated pooling machines

• TaqMan platform requires lots of room. Total NAT laboratory space doubled

• MBC detected ~36 WNV+ blood donors, mostly in Nebraska, South Dakota and Iowa

Page 21: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

More Automated System

COBAS AmpliPrep

COBAS TaqMan (96/48)

Hamilton Pipettor

Page 22: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,
Page 23: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

WNV Human cases and deaths

State Cases Deaths Colorado 2647 61 Nebraska 1942 29 South Dakota 1039 14 Texas 717 37 North Dakota 617 5 Wyoming 375 9 Pennsylvania 237 8 Total 9862 264

Page 24: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

+ WNV rate weekly (6/30-9/30)WNV Incidence

0.000%

0.100%

0.200%

0.300%

0.400%

0.500%

0.600%

0.700%

0.800%

1 2 3 4 5 6 7 8 9 10 11 12 13

Week

% P

osi

tive CBBLAN

MBC

Siouxland

SFSV+Avera

1 / 500

Page 25: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

2004 map as of 10/26/04

Page 26: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

2004 counties 10/26/04

Page 27: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

WNV+ blood donors - 10/26/04

Page 28: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

2004 WNV Transfusion transmission in Arizona

• MMWR Sept 17, 2004 p 842• In 2003 blood centers interdicted ~800 blood

components via pooled testing. Because of 6 cases of transfusion transmission, a policy for single donor (SD) testing was implemented for 2004.

• 3 days before switch to SD in Arizona (from TMA pool of 16), a 43 yo with severe diabetes was transfused following a knee amputation. He subsequently developed WNV and died. The units were traced and one donor was shown to be WNV+ by SD but not pooled testing.

Page 29: Black Bugs Blood: West Nile Virus & the Blood Supply Infectious Transfusion Risks, Screening Blood donations for WNV and other icky things Jed Gorlin,

Implications

• Despite reduced pool size and plans to implement single donor testing, window period cases of WNV continue to occur.

• There have been two HIV transmissions despite pooled NAT testing

• Both manufacturers are working to create more automated systems that facilitate single donor testing. These will be more expensive, but will allow greater throughput than current manual tests