Guidance

Chapter 12: interpreting donor test results

Updated 21 May 2024

Time course of an infection

Following exposure to, and infection by, a microbiological agent there is a period of time during which no microbe can be readily recovered from the host. This is classically called the eclipse period (see Figure 1). Donations taken during this period are unlikely to be infectious but in practice this would not be safe and should be avoided.

The time from infection to the onset of detectable infectivity depends upon the method used for detection of infection. This period of infectivity which cannot be detected is colloquially called a ‘window’ and represents the duration of undetectable infectivity. This ‘window’ is:

• shortest for genomic (nucleic acid testing (NAT)) and antigen tests
• longest for antibody tests

For practical purposes, the time from infection to first detection of a marker is referred to as the ‘window period’.

Figure 1: diagrammatical representation of the eclipse and window

Risk assessment

The risk of transmitting an infection where microbiological antibody tests are negative may be quantified and is termed the residual risk. The residual risk for transmitting an infection is not solely dependent on the characteristics of the specific test used (sensitivity and specificity) but is also dependent on the incidence of infection within a defined population and the length of the window period.

The calculated residual risk estimates for the transmission of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) in solid organ donors in the UK are included in Table 1. These figures have been calculated from results of microbiological testing in approximately 8,000 potential solid organ donors in the UK for the period 2010 to 2014. Calculated residual risk estimates are provided for screening protocols utilising antibody-based testing and those that would incorporate NAT testing.

Table 1: residual risk estimates for undetected blood borne virus infection in those testing negative at the time of solid organ donation using either standard serological tests or with the addition of NAT

	Antibody alone	Antibody plus antigen	Addition of NAT
HBV	Not relevant [note 1]	0.43 (0.03 to 3.99) [note 2]	0.30 (0.02 to 2.83) [note 3]
HCV	5.96 (0.82 to 37.89) [note 4]	0.71 (0.10 to 4.43) [note 5]	0.30 (0.04 to 1.93) [note 6]
HIV	Not relevant [note 1]	0.08 (0.02 to 0.21) [note 7]	0.04 (0.005 to 0.10) [note 8]

Figures are number of undetected cases per 100,000 donors (95% confidence intervals).^{[footnote 1]}

Table 1 notes:

• note 1: antibody alone test not performed for donor characterisation
• note 2: anti-HBc antibody plus HBsAg
• note 3: anti-HBc antibody plus HBsAg plus HBV DNA PCR
• note 4: anti-HCV antibody
• note 5: anti-HCV antibody plus HCV antigen
• note 6: anti-HCV antibody plus HCV NAT
• note 7: anti-HIV plus HIV antigen (combo test)
• note 8: HIV combo test + HIV RNA PCR

Positive screening tests and confirmatory tests

Standardised terminology must be adopted by all involved in the donation process regarding terminology used during donor testing.

Positive test results on microbiological screening tests require that further confirmatory testing be undertaken. The nature of that confirmatory testing is dependent on the pathogen being tested for. The time scale in which confirmatory testing will be carried out is dependent on the nature of the planned donation and the confirmatory tests required.

It is recognised that confirmatory testing of initial reactive tests may not be available at the time of transplantation following deceased organ donation. Similarly, results of other specialised microbiological tests may not be available at the time of donation and transplantation. In these circumstances, transplantation of organs may be undertaken if the benefits are deemed greater for the patient than the risk of remaining on the waiting list but only after due consideration of the available results including, where necessary, specialist advice and after informed patient consent.

Centres receiving solid organs for transplantation are not required to repeat the donor microbiological screening tests. When microbiological testing is repeated by recipient centres or tissue establishments, any and all discordant results obtained following repeat testing must be made available to other centres that have accepted material from that donor. Results must also be communicated to the Organ Donation and Transplant duty office, NHS Blood and Transplant, so that all interested parties are informed in a timely manner.

The donor testing laboratory has responsibility for ensuring that confirmatory testing of positive screening tests is completed.

The organ, donor or tissue procurement organisation has responsibility for the communication of the confirmatory testing results to relevant individuals and organisations.

Centres or organisations accepting material from donors for whom confirmatory testing is required also have a responsibility and must ensure that the results of confirmatory testing are known and that patient management is modified as appropriate.

Where organs, tissues or cells from a donor have been sent to other tissue establishments or centres, they must be told about repeat reactive and positive test results. This is to prevent unsuitable tissues or cells being transplanted as it often takes a considerable time to get definitive results from confirmatory testing. For tissues with a long shelf life, no material should be released until all confirmatory testing for a mandatory marker is complete and shown to be negative.

In the case of a deceased donor, there must be an operating policy detailing measures that ensure that close contacts of the deceased donor are appropriately informed of results that may have implications for close contacts of the donor. The responsibility for ensuring that close contacts are informed rests with the organisation that obtains consent or authorisation for donation. There is a need to ensure at a local level that appropriate counselling of affected persons can and will take place if desired by close contacts of the donor. This is considered a duty of care to the donor and/or donor’s family. The need to inform close contacts of relevant results also highlights the importance of completion of all testing for all potential donors tested regardless of whether or not donation and/or transplantation occurred.

Decisions based on specific test results

The sections below provide guidance on donation decisions where test results show the presence of specific viruses or infections.

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Cytomegalovirus (CMV)

Table 2: positive serological result in an allograft donor: CMV

Test result suggesting possible donor CMV infection	Organs	Tissues	Hematopoietic stem and progenitor cells (HSPC), TC and human embryonic stem cells [note 9]	Gametes and embryos
Anti-CMV immunoglobulin G (IgG) positive	Donation permitted Informs need for post-transplant CMV monitoring and management	Donation permitted	Donation permitted Informs need for post-transplant CMV monitoring (CMV NAT positive donor is unsuitable for use [note 10])	Donation permitted Match serology status to donor if possible

Note 9: all umbilical cord donations are tested prior to issue by CMV NAT. In exceptional circumstances, a life-preserving donation containing CMV DNA might be used for a recipient whose serum contains anti-CMV antibody in accordance with Chapter 15. Routine CMV prophylaxis should be administered post-transplant and/or routine CMV viral load surveillance instituted.

Note 10: defer donor until NAT negative.

Epstein-Barr virus (EBV)

Organs, HSPC and TC from an EBV seropositive donor may transmit infection to a seronegative recipient. EBV may also reactivate in sero-positive recipients.

Table 3: positive serological result in an allograft donor: EBV

Test result suggesting possible EBV infection of donor	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
Anti-EBV IgG	Donation permitted Informs need for post-transplant EBV monitoring	Donation permitted	Donation permitted Informs need for post-transplant EBV monitoring	EBV testing not required

Hepatitis B virus (HBV)

Screening for HBV infection must include testing for HBsAg and anti- HBc (total antibodies).

Samples giving repeat reactivity for HBsAg should undergo a confirmatory test and additional markers performed.

HBV DNA PCR and anti-HBs should be undertaken where screening tests suggest current or past HBV infection in order to inform management of the recipient. The results should be available within 72 hours of initial testing.

The detection of confirmed HBsAg and/or HBV DNA indicates current infection.

Detection of anti-HBc in the absence of HBsAg indicates past hepatitis B virus infection. However, donations from a proportion of individuals whose sera contain anti-HBc in the absence of anti-HBs may still be infectious. Although this is unlikely, the EU Tissue Directives require testing tissue donors for anti-HBc.

Detection of anti-HBs and the absence of anti-HBc suggests previous immunisation.

Proven acute or chronic HBV infection is a contra-indication to tissue donation.

Organ transplantation and cell transplantation may be undertaken after consideration of the following and with the informed consent of the potential recipient (relevant specialist advice must be sought):

• status of HBV infection in potential donor - acute or chronic infection, previous infection
• nature of proposed transplant - liver transplant, non-liver transplant
• HBV anti-viral therapy use in recipient
• HBV immunisation status of recipient

HBV has been contracted from contaminated liquid nitrogen tanks. If cells, gametes or tissues requiring long term cryopreservation from an unscreened donor or an HBV-infected donor are to be stored, see Chapter 11.

Table 4: positive serological and/or positive NAT result in an allograft donor - HBV

Test results suggesting possible donor HBV infection	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos (non-partner donation) [Note 11]
HBsAg positive	Relative contraindication to donation [note 12]	Contraindication to donation	Contraindication to donation	Contraindication to donation
HBV DNA NAT positive	Relative contraindication to donation [note 12]	Contraindication to donation	Contraindication to donation [note 12]	Contraindication to donation
Anti-HBc positive HBsAg Negative and/or NAT negative	Donation permitted [note 12]	Donation permitted [note 13]	Donation permitted [note 13]	Contraindication to donation

Note 11: partner donation with direct use (donation and use without any banking) does not require microbiological testing (see Chapter 6, Table 1).

Note 12: see box above table on organ transplantation and cell transplantation.

Note 13: if HBV NAT is not performed, then donation is permitted if anti HBs are over 100 IU/l

Hepatitis C virus (HCV)

Screening for HCV infection employs either an antibody-only assay or a combined HCV antigen or antibody assay and molecular tests for HCV RNA.

Positive samples should undergo confirmatory testing. The detection of confirmed anti-HCV antibody indicates past or current infection. Confirmed HCV antigen or and/or RNA detection indicates current infection.

Effective anti-viral therapy resulting in sustained virological response for HCV is now available.

Effective treatment for HCV infection in the recipient may be undertaken either before or after transplantation.

Re-infection with HCV can occur in patients with a previous sustained virological response following HCV treatment.

HCV infection in the potential donor does not amount to an absolute contra-indication to donation of material for life-preserving transplantation. However, the net benefit of transplantation must be considered against the risk of not receiving that specific transplant. This risk-benefit analysis allows for the potential use of a transplant from a HCV infected donor to a non-infected recipient.

Table 5: positive serological and/or positive NAT result in an allograft donor - HCV

Test results suggesting possible donor HCV infection	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
HCV IgG antibody	Relative contraindication to donation	Absolute contraindication to donation [note 14]	Relative contraindication to donation [note 14]	Absolute contraindication to donation [note 15]
HCV RNA NAT or HCV combination Ab/Ag (‘combo’) test	Relative contraindication to donation	Absolute contraindication to donation [note 14]	Relative contraindication to donation [note 14]	Absolute contraindication to donation [note 15]

Note 14: The European Union Tissues and Cells Directive (EUTCD) prohibits donation from individuals with a “history, clinical evidence, or laboratory evidence of HIV, acute or chronic hepatitis B (except in the case of persons with a proven immune status), hepatitis C and HTLV I/II, transmission risk or evidence of risk factors for these infections”, unless justified on the basis of a documented risk assessment approved by the responsible person as defined in Article 17 of Directive 2004/23/EC.

The categorisation of a relative contraindication for HCV is indicative of the current knowledge of treatments for this virus.

Note 15: EUTCD states that for “donation other than by partner” of gametes and embryos the donor “must be negative” for HCV.

Human immunodeficiency virus (HIV)

Screening for HIV infection must include a combined HIV antigen or antibody assay.

Samples giving repeat reactivity in antibody or combined antigen or antibody assays must undergo additional testing to confirm HIV infection including NATs for HIV RNA.

Confirmed detection of specific anti-HIV 1 and 2 antibodies and/or HIV RNA and/or HIV antigen indicates current infection.

HIV infection is an absolute contraindication for tissue transplantation.

The use of organ and cells from HIV-infected individuals may be considered in the setting of HIV-infected recipients. Assessment of the potential donor must include details of previous HIV assessment and management in that individual. Specialist advice in the management of HIV must be sought to inform the decision-making process.

The intentional use of organs and cells from an HIV-infected individual in a non-infected patient is considered to be contraindicated. However, it is recognised that effective treatment for HIV exists in the form of Highly Active Anti-Retroviral Therapy (HAART), with life expectancy of successfully treated individuals being comparable to those without HIV infection. Therefore, the possibility may arise where transplantation of organs or cells from an HIV-infected donor is considered for a non-HIV infected recipient following an opinion from a clinician with expertise in the management of HIV infection allowing for HIV management after transplantation and with the full informed consent of the potential recipient.

Table 6: positive serological and/or positive NAT result in an allograft donor - HIV

Test results suggesting possible donor HIV infection	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
HIV 1/2 antibody/ antigen	Relative contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation
HIV RNA NAT	Relative contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation

Human T cell lymphotropic virus (HTLV)

Screening for HTLV infection employs an antibody-only assay.

Positive samples should undergo confirmatory testing. Confirmation of specific anti-HTLV antibodies indicates current infection. Reference NAT testing may be used to confirm HTLV infection.

Material from donors with repeat positive anti-HTLV antibody testing can be released for clinical use providing the antibody reactivity is shown to be non-specific in confirmatory testing.

Although confirmation of HTLV status can be completed prior to use of tissues and cells, in the setting of deceased organ donation confirmatory results are unlikely to be available. In this situation, specialised advice should be sought to help provide an assessment as to the likelihood that an initial reactive result represents a true infection, the probability of which will depend on the details obtained in the donor assessment. The decision to proceed with solid organ transplantation following an initial reactive HTLV antibody test is dependent on an assessment of the net benefit of receiving that transplant when compared to the risk of not receiving that specific transplant.

Table 7: repeat reactive result in an allograft donor: HTLV

Test result suggesting possible HTLV 1/2 infection	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
Anti-HTLV 1/2 IgG	Relative contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation	Absolute contraindication to donation

Toxoplasma gondii

Although the results of serological tests demonstrating past or current Toxoplasma gondii infection will be available in the setting of live donation, serological evidence of infection may only be available after deceased-donor solid organ transplantation and can therefore only inform post-surgical management.

Toxoplasma gondii is inactivated by low temperatures. Freezing for 24 hours at minus 20 degrees Celsius or lower inactivates toxoplasma in blood and plasma. Freezing and subsequent storage of tissues at minus 20 degrees Celsius or lower will inactivate tissue cysts. However, cryopreservation of tissues preserves Toxoplasma cysts, so the risk of transmission is not eliminated from cryopreserved as distinct from directly frozen tissues.

Table 8: repeat reactive serological result in an allograft donor: Toxoplasma gondii

Test result suggesting possible Toxoplasma gondii infection of donor	Organs [note 16]	Tissues	HSPC, TC and human embryonic stem cells [note 17]	Gametes and embryos
Anti-Toxoplasma gondii IgG positive (IgM should also be tested for in the setting of HSPC and TC donation)	Donation permitted Informs need for prophylaxis in heart recipients	Donation permitted	Inform need for prophylaxis and donor deferral if recent acute infection	Not required

Note 16: the risk of acquiring Toxoplasma gondii infection from the transplant, rather than developing Toxoplasma gondii disease from endogenous reactivation in the recipient under immunosuppression, results from a serological mismatch between an infected donor (antibody positive) and a naive seronegative recipient in the absence of prophylaxis.

Note 17: avoid donors with evidence of recent or acute infection (for example, IgM positive).

Hepatitis E virus (HEV)

SaBTO has recently published guidance recommending HEV NAT testing for donors of organs, tissues and cells.

Results of donor HEV testing may not be available prior to the use the transplantation of organs but will usually be available before the use of tissues and cells.

Table 9: HEV nucleic acid testing in an allograft donor

Test result suggesting possible donor HEV infection	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
HEV NAT	Donation permitted Informs post-transplant management	Donation permitted	Donation permitted Informs post-transplant management	Donation permitted

Treponema pallidum (syphilis)

The interpretation of syphilis serology can be difficult, and may require help from an experienced clinician.

Serological tests for are not specific for Treponema pallidum subspecies pallidum (syphilis) and may detect any of the trypanomatoses (syphilis, yaws, pinta and bejel), and therefore when positive, correlation of test results with the history, epidemiological exposure and clinical features is required.

Table 10: positive syphilis serology in an allograft donor

Test result	Organs	Tissues	HSPC, TC and human embryonic stem cells	Gametes and embryos
Syphilis EIA positive (initial screen)	Donation permitted	Relative contraindication to donation [note 18]	Donation permitted	Relative contraindication to donation [note 18]
Non treponemal test positive [note 19] (that is, VDRL or RPR)	Donation permitted [note 20]	Relative contraindication to donation	Donation permitted [note 20]	Relative contraindication to donation
Treponemal test positive [note 21] ( that is, TPPA or THPA)	Donation permitted [note 20]	Relative contraindication to donation [note 18]	Donation permitted [note 20]	Relative contraindication to donation

Note 18: a donation from a positive donor may be considered following careful consideration of the risk-benefit ratio of the transplant, taking into account which tests are reactive and the donor’s treatment history if applicable, and the informed consent of the intended recipient.

Note 19: a high non-treponemal test titre (greater than 1:16) is suggestive of a recent or active infection, in the absence of a clear history of treatment. However, a low titre does not out-rule active infection.

Note 20: where a recipient has been exposed to a potentially infectious donation a risk assessment must be undertaken, and expert advice sought from an infectious diseases or genitourinary medicine physician to ensure administration of timely and adequate antimicrobial therapy, and to guide serological follow-up.

Note 21: treponemal specific tests can remain positive indefinitely despite adequate treatment.

Human herpes virus (HHV-8), also known as Kaposi sarcoma-associated herpes virus (KSHV)

SaBTO has separate guidance on the recommendation for serological HHV-8 screening in deceased organ donation.

Results of donor HHV-8 antibody screening are not currently available prior to the transplantation of organs from deceased donors. Results are meant to inform recipient monitoring and early diagnosis, in order to prevent severe outcomes in primary graft-related infection.

Seropositivity in an asymptomatic deceased donor, if known pre-transplantation, is not an absolute contra-indication for organ donation, but must be carefully assessed with the support of a local transplant unit consultant microbiologist or virologist.

Where there is confirmed HHV-8 associated disease, the donation of organs, tissues and cells is contraindicated. Apart from the sporadic form of Kaposi’s sarcoma, all other forms of disease present clinically in the setting of profound immunosuppression and certain risk factors, hence the caution required as regards to donation.

Transmissible spongiform encephalopathies (TSEs)

TSEs (otherwise known as prion diseases) are a group of fatal transmissible neurodegenerative disorders that in humans occur in sporadic, genetic and acquired forms. The commonest human TSE, Creutzfeldt-Jakob disease (CJD), occurs in all 3 forms:

• genetic (gCJD)
• sporadic (sCJD)
• acquired:
  • variant CJD (vCJD)
  • iatrogenic CJD (iCJD)

The transmissible agent (or prion) is presently not fully characterised but is generally considered to be composed principally of a misfolded form (designated PrP^Sc) of the normal prion protein (designated PrP^C).

sCJD has been transmitted from one patient to another through medical or surgical procedures involving neurosurgical instruments, brain electrodes, tissue (human cornea and dura mater grafts) and tissue extracts (human pituitary hormones). There have been no known transmissions of vCJD via surgery or use of tissues or organs to date. However there has been transmission of vCJD infection via transfusion of blood (non-leucodepleted red cells) and, in one instance, probably by a blood product (factor VIII).

Donor deferral issues centre around the potential for transmitting TSEs during organ and tissue transplantation and the administration of blood or blood products. Deferral of donors is complex. An effective practical screening test for the detection of misfolded prions in donor blood, or other tissues, is not available at present. The prevalence of asymptomatic infected persons in the UK is uncertain (although, for public health purposes, it is presently considered to be around 1 in 2,000^{[footnote 2]}) and there is additional uncertainty as to the infectivity potential of those presumed to be asymptomatically infected.

There are a number of risk factors for human TSEs that have been identified, aside from age, geographical residence and genetic factors, including:

• prior exposure to human blood
• dura mater grafts
• pituitary-derived hormones
• contaminated surgical instruments

In addition, a number of individuals have been notified that they are at increased risk of CJD or vCJD for public health purposes, due to their exposure to one or more risk factors. Guidance from the Advisory Committee on Dangerous Pathogens (ACDP) TSE Working Group is available from Minimise transmission risk of CJD and vCJD in healthcare settings. Concerns have also been raised of a theoretical transmission risk from human urine-derived gonadotrophins (Metrodin HP). There is no evidence that donated human eggs can transmit CJD.

Individuals with a confirmed or suspected TSE, a neurological disease of unknown aetiology or those who are blood relatives of persons with genetic CJD cannot be accepted as donors of organs or tissues. However, if a donor has had 2 or more blood relatives develop a prion-associated disease and, following genetic counselling and/or testing they have been informed they are not at risk, they may be accepted for donation.

Tables 11 and 12 summarise the exclusions from organ and/or tissue donation, based on possible TSE exposure.

Level of risk or exposure should be clarified and weighed, on an individual basis, against the expected benefit of the transplant and the availability of alternative donors. The recipient (and/or relatives) should be informed of the nature of the estimated risk of vCJD transmission.

Definite transfusion is defined as at least one of the following:

• recorded in medical notes available to clinical staff at time of donation
• documented during interview
• reported by GP

For tissue and organ donors, probable transfusion is defined as one or both of the following:

• previous major surgery
• previous major accident

Ocular tissue donors should not be excluded if they have a history of definite or probable transfusions, in view of supply issues. However, it is essential that donors excluded on the basis of public health measures are not accepted as ocular tissue donors.

Table 11: exclusions from organ and/or tissue donation based on possible TSE exposure - live tissue donors

	Solid organ	Live tissue: bone	Live tissue: HSPC	Live tissue: gametes and embryos
Definite, probable or possible case of human TSE, including CJD and vCJD	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual with a neurological disease of unknown aetiology	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual whose blood relatives have had familial CJD [note 22]	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual ‘presumed infected’ with vCJD [note 23]	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual ‘at increased risk of CJD or vCJD’ (for public health purposes) [note 24]	Individual assessment required [note 25]	Absolute contra-indication	Individual assessment required [note 25]	Absolute contra-indication
History of definite [note 26] or probable [note 27] blood transfusion since 1980	Individual assessment required [note 25]	Absolute contra-indication	Individual assessment required [note 25]	Individual assessment required [note 25]
History of receipt of dura mater graft	Individual assessment required [note 25]	Absolute contra-indication	Individual assessment required [note 25]	Individual assessment required [note 25]
History of definite receipt of tissue since 1980	Individual assessment required [note 25]	Absolute contra-indication	Individual assessment required [note 25]	Individual assessment required [note 25]
History of receipt of pituitary derived growth hormone and/or gonadotrophin	Individual assessment required [note 25]	Absolute contra-indication	Individual assessment required [note 25]	Individual assessment required [note 25]
History of receipt of organ	Individual assessment required [note 25]	Absolute contra-indication	Absolute contra-indication	Individual assessment required [note 25]

Note 22: however, if a donor has had 2 or more blood relatives develop a prion-associated disease and, following genetic counselling, they have been informed they are not at risk, they may be accepted for donation.

Note 23: donors who have received blood components, tissues and/or organs from donors who have gone on to develop vCJD.

Note 24: donors who have been notified that they are at increased risk of vCJD or CJD (for public health purposes) due to possible exposure.

Note 25: level of risk or exposure should be clarified and weighed, on an individual basis, against the expected benefit of the transplant and the availability of alternative donors. The recipient (and/or relatives) should be informed of the nature of the estimated risk of vCJD transmission.

Note 26: definite transfusion is defined as at least one of the following:

• recorded in medical notes available to clinical staff at time of donation
• documented during interview
• reported by GP

Note 27: for tissue and organ donors, probable transfusion is defined as either or both of the following:

• previous major surgery
• previous major accident

Table 12: exclusions from organ and/or tissue donation based on possible TSE exposure - deceased tissue donors

	Musculo-skeletal (ligaments, tendons and cartilage)	Bone and processed bone	Ocular	Skin, heart, valve, pancreatic islets or hepatocytes
Definite, probable or possible case of human TSE, including CJD and vCJD	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual with a neurological disease of unknown aetiology	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual whose blood relatives have had familial CJD [note 22]	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual ‘presumed infected’ with vCJD [note 23]	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
Individual ‘at increased risk of CJD or vCJD’ (for public health purposes) [note 24]	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
History of definite [note 26] or probable [note 27] blood transfusion since 1980	Absolute contra-indication [note 28]	Absolute contra-indication	Accept [note 29]	Accept
History of receipt of dura mater graft	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
History of definite receipt of tissue since 1980	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Accept
History of receipt of pituitary derived growth hormone and/or gonadotrophin	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication
History of receipt of organ	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication	Absolute contra-indication

Note 28: do not exclude if transfusion is within one week prior to death.

Note 29: ocular donors should not be excluded if they have a history of definite or probable transfusions, in view of supply issues. However, it is essential that donors excluded on the basis of public health measures are not accepted as ocular donors.

See a list of all chapters in this guidance

1. See the full publication for data from potential deceased organ donors who inject drugs: Katy L Davison, Ines Ushiro-Lumb, Marcus Lawrance, Patrick Trotter, James J Powell and Susan R Brailsford, Infections and associated behaviours among deceased organ donors: Informing the assessment of risk. Transplant Infectious Disease (2019) 21:e13055, doi: 10.111/tid.13055. ↩

2. Gill and others, Prevalent abnormal prion protein in human appendixes after bovine spongiform encephalopathy epizootic: large scale survey. British Medical Journal, 15 October 2013. 347:f5675. doi: 10.1136/bmj.f5675. ↩