Transfusion and risk of infection in Canada: Update 2012

Question 1

What are the steps to prevent infections from blood transfusions?

Answer 1

1. Restrictive transfusion policies and effective blood conservation programs
2. Evidence based effective policies for donor selection, screening, product collection, testing, and infusion

Question 2

What steps are taken in Canada to minimize infection risks of transfusion?

Answer 2

1. Blood collection from volunteer, unpaid donors
2. Donor interview and selection protocols
3. Careful aseptic technique procedures for collection and infusion
4. Diversion of the first 40mL of blood collected into a diversion pouch
5. Donor screening by serological and other tests including bacterial detection in platelets
6. Viral inactivation procedures used in manufacturing plasma-derived products
7. Leukocyte reduction techniques to reduce the transmission risk of white-cell associated viruses i.e. CMV

Question 3

What are blood donors tested for?

Answer 3

1. HIV type 1-2 and subtype O (Antibody/NAT)
2. HBV (HbsAg, Anti-HBc, NAT)
3. HTLV type I/II (Antibody)
4. Syphilis (Treponemal test/PK-TP)
5. HCV (Antibody/NAT)
6. WNV (NAT all units year round at CBS, all units tested during the summer plus testing donors with travel risk of WNV in the winter at HQ)
7. Other: CMV antibody on selected units only, Trypanosoma cruzi (Chagas) antibody on at risk fonors)
8. Bacteria: bacterial culture on platelets

Question 4

What specific manufacturing procedures are available for virus inactivation or removal?

Answer 4

1. Inactivation by heat: CMV, HAV, HBV, HCV, HIV, WNV, Parvovirus B19
2. Inactivation by solvent/detergent: CMV, HBV, HCV, HIV, WNV. Not inactivated: HAV, Parvovirus B19, enteroviruses
3. Ultrafiltration using 35nm and 15nm filters: removes even small viruses but also macromolecules (i.e. FVIII)
4. Leukocyte depletion: CMV, HTLV type I/II, not inactivated: non-WBC associated viruses

Question 5

Which blood product has the highest risk of bacterial contamination and why?

Answer 5

Platelets as they are stored at room temperature

Question 6

What are the manufacturing steps to decrease infectious risks for cryoprecipitate?

Answer 6

1. Virus risk pre-inactivation process

2. Pools screened for HIV, HCV, HBV, HTLV type I/II

Question 7

What are the manufacturing steps to decrease infectious risks for Factor VII?

Answer 7

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. AI(OH)3 +/- nanofiltration +/-vapour heat treatment

Question 8

What are the manufacturing steps to decrease infectious risks for Factor VIII?

Answer 8

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Pasteurization process
4. Solvent/detergent +/- dry heat treatment

Question 9

What are the manufacturing steps to decrease infectious risks for Factor IX?

Answer 9

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Vapour heating

Question 10

What are the manufacturing steps to decrease infectious risks for antithrombin concentrates?

Answer 10

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Sephadex A-50
4. Solvent/detergent +/- DEAE
5. Sepharose FF chromatography +/- nanofiltration

Question 11

What are the manufacturing steps to decrease infectious risks for albumin?

Answer 11

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Isolation of filtrate +/- isolation of filtrate IV +/- isolation of filtrate d +/- pasteurization +/- cold ethanol fractionation +/- heat treated

Question 12

What are the manufacturing steps to decrease infectious risks for IVIG products?

Answer 12

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Cold ethanol fractionation
4. Solvent/detergent +/- caprylate +/- column chromatography +/- low pH treatment +/- nanofiltration +/- heat treatment +/- octanoic acid fractionation +/- depth filtration +/- virus filtration

Question 13

What are the manufacturing steps to decrease infectious risks for IMIG?

Answer 13

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Cold/ethanol fractionation
4. Solvent/detergent +/- heat inactivation +/- precipitation filtration +/- ultra filtration +/- dia filtration

Question 14

What are the manufacturing steps to decrease infectious risks for specific antibody products?

Answer 14

1. Virus risk pre-inactivation process
2. Pools screened for HIV, HCV, HBV, HTLV type I/II
3. Cold ethanol fractionation or ion exchange column chromatography
4. solvent/detergent
5. virus filtration ± heat inactivation
6. Anion-exchange column chromatography ± Planova 20N Virus Filter ± solvent/detergent ± cold ethanol fractionation ± heat inactivation ± precipitation filtration ± ultra filtration ± diafiltration

Question 15

What bacterial agents are associated with acute infection during pRBC transfusion?

Answer 15

Storage: 1-6 degrees Celsius x 35-42d

Agents: Yersinia enterocolitica gram-negative, including Pseudomonas species

Question 16

What bacterial agents are associated with acute infection during whole blood transfusion?

Answer 16

Storage: 1-6 degrees Celsius x 35-42d

Agents: Gram-negative, including Pseudomonas species

Question 17

What bacterial agents are associated with acute infection during platelet transfusion?

Answer 17

Storage: 20-24 degrees Celsius x 5d

Agents: Skin flora (Staph epidermidis, Strep species, diphtheroids), Salmonella species, E coli, Enterococci species, Clostridium species, Serratia marcescens

Question 18

What bacterial agents are associated with acute infection during plasma transfusion?

Answer 18

Storage: Frozen, once thawed can be held
at 1°C to 6°C for 24 h

Agents: S. aureus, Pseudomonas aeruginosa

Question 19

What are adverse reactions to transfusions in Canada?

Answer 19

1. Severe allergic/anaphylactic reaction
2. Acute hemolytic transfusion reaction
3. Delayed hemolytic transfusion reaction
4. Transfusion-associated circulatory overload
5. Transfusion-related acute lung injury
6. Possible transfusion-related acute lung injury
7. Transfusion associated dyspnea
8. Bacterial contamination
9. Hypotensive transfusion reaction
10. Post-transfusion purpura

Question 20

What are the estimated risk of infectious agents for which all blood donors are tested in blood or blood products?

Answer 20

1. HIV 1 in 8-12 million
2. HCV 1 in 5-7 million
3. HBV 1 in 1.1-1.7 million
4. HTLV I or II in 1 in 1.3million
5. WNV no reported cases
6. Bacteria: apheresis platelets 1 in 105 000, platelet pools 1 in 47 000
7. Syphilis <1 in 100 million

Question 21

What are the estimated risk of infectious agents which are tested on occasion in blood or blood products?

Answer 21

1. CMV rare

2. Chagas no new cases in 5 years

Question 22

What are the estimated risk of infectious agents which are not tested in blood or blood products?

Answer 22

1. Parvovirus B19 1 in 5000 to 1 in 20 000
2. GBV-C 1-2 in 100
3. TTV 1 in 100
4. SEN-V 1 in 100
5. HHV-8 unknown
6. Malaria no new cases in 10y
7. Babesiosis 1 case in 2001
8. vCJD risk unknown (<1 in 10 million)

Question 23

What are the estimated risks of viruses for which all blood donors are tested in manufactured plasma-derived products?

Answer 23

1. HIV <1 in 10 million
2. HCV <1 in 10 million
3. HBV <1 in 10 million
4. HTLV I and II theoretical

Question 24

What are the estimated risks of other viruses in manufactured plasma-derived products?

Answer 24

1. CMV theoretical
2. Parvovirus B19: theoretical if heat inactivation, 1 in 100 000 to 1 in 1 million otherwise
3. WNV theoretical

Question 25

What are the estimated risks of parasites in manufactured plasma-derived products?

Answer 25

Only a theoretical risk for malaria, chagas, and babesiosis

Question 26

What are the estimated risks of prions in manufactured plasma-derived products?

Answer 26

vCJD theoretical risk of <1 in 100 million