Blood, Blood, Blood!

Mixed response this week to the news that the NHS Blood Donor Service is going to start accepting donations from Men who have have sex with Men (MSM), but only if they haven’t had sex with another man in the past 12 months. A good summary of some Conservative Christian reaction is this piece from the Christian Institute (CI).

Comment: blood donation rules changed for equality’s sake

Blood transfusions save lives. Sensible rules about who can and cannot donate blood are there to safeguard the national blood supply. Decisions about who may safely donate blood should be left to medical science, not political lobbying or equality laws.

But it was announced last week that, starting 7 November, the rules on blood donation are set to change. Under the current rules, a man who has ever had sex with another man is not permitted to donate blood. This is because men who have had sex with men (MSM) are at a far greater risk of carrying a blood-borne virus.

This is not a historical risk that has since disappeared. It is still very real. Earlier this year the Health Protection Agency announced that the number of new HIV diagnoses has nearly doubled over the past ten years. The HPA said that numbers are increasing “especially in men who have sex with men”.

Campaign

In fact there is a European law that legally requires blood services to permanently exclude anyone whose sexual behaviour puts them at high risk of acquiring severe infectious diseases that can be transmitted by blood – which is why a survey of blood services in 23 European nations found that MSM were permanently excluded from giving blood in 20 nations.

MSM are not the only people who have been prevented from donating blood. Anyone who has ever worked as a prostitute may never give blood, nor can anyone who has ever injected illegal drugs. Anyone who has an active cold sore may not give blood. Anyone who has had a tattoo or semi-permanent make-up in the last four months may not give blood. Anyone who has received a blood transfusion anywhere in the world since 1 January 1980 may not give blood. The list goes on.

But following lobbying from homosexual campaigners, the ban on active homosexual men giving blood has been overturned by the Government. In particular, campaigners have said the exclusion is unlawful under the sexual orientation regulations, which they themselves lobbied for. The regulations were introduced in 2007 and later incorporated into the Equality Act 2010.

So now homosexual men will be allowed to donate blood, as long as they haven’t had sex with a man in the last twelve months. Even this is not enough for some campaigners. Peter Tatchell wants no deferral period at all.

Risk

Until recently, the National Blood Service said allowing MSM to donate blood could “result in a fivefold increase in the risk of HIV-infected blood entering the blood supply”.

The 12-month deferral rule is a huge cave-in to the demands of the homosexual lobby. Earlier this year, it was reported in the media that the Government was considering relaxing the safeguard from a lifetime exclusion to a ten-year deferral period.

As recently as April, experts said that would increase the risk of HIV entering the national blood supply by about 2.5 per cent. The same experts said a five-year deferral period would increase the risk by almost five per cent. So, it is not unreasonable to ask how high is the increase in risk with a 12-month deferment period? The official report into the matter suggested the increased risk could be as high as ten per cent.

But the risks are not that high in the first place, says the committee that recommended the change. It said there have been improvements to the testing and handling of donated blood. However, it also said that changes to equality laws and social attitudes were “reasons to consider change”.

Now there are aspects of this piece that are correct. It is perfectly true that MSM are, on average, more likely to have HIV (including undetected HIV) then non-MSM people. Secondly, it’s also true that a number of other people are excluded from giving blood on the basis of their previous behaviour (prostitutes, having sex with prostitutes, having tattoos etc). It’s also worth pointing out that the current ban on all MSM is not explicitly homophobic in that not every MSM is “gay” in any sense.

But putting that aside, the main conjecture of the CI article is that the reason the rules are being changed are due to political pressure and lobbying from gay rights groups. Is this necessarily correct? Is the real reason the changes are being made because of good science, not bad legislation?

Just before we answer that question, it’s worth pointing out that these “macro-level” judgements on particular groups of people are made all the time by all kinds of agencies and companies. For example, walk into a Bank and ask for a loan and a macro-level assessment will be made of you building a risk profile based not only on your personal credit history (or lack of it) but also the average behaviour of people who share characteristics as you (such as age, job, time living at current address). No-one objects to these “shared factors” being used in the Banks’ judgements and indeed when they look at you to make a judgement on whether to give you insurance they are even allowed by EU Law to include our sex as one of the factors in their final decision.

So the use of average characteristics of shared groups is a standard practice and it was the basis for the original ban on all MSM donating blood. However, SaBTO (the Advisory Committee on the Safety of Blood, Tissue and Organs) has recently undertaken a review of the dangers of certain groups of people giving blood and this review was the basis of the proposed change in the rules. The review can be read here.

It’s an interesting read. Yes, there is a discussion of how equality legislation affects the decisions of who to exclude, but it is not cited as a major factor for the new decision. On page 42 of the Review SaBTO writes,

Issues of blood donation regulation are covered by a number of legal provisions in the UK. It has been clear for some time that blood components are ‘products’ for the purposes of the Consumer Protection Act 1987 and the European Directive behind it on products liability (85/347/EEC). The key legal judgment is that of Mr Justice Burton in A and Others v the National Blood Authority and Others. This successful case was brought on behalf of 114 persons infected with Hepatitis C following blood transfusions between 1988 and 1991. This judgment confirmed a ‘strict liability’ test based on the legitimate expectations of the public as to the safeness of the ‘product’.

The national and international legal requirements in relation to blood donation and its safety must, however, also be read in the light of the Equality Act 2010, which consolidates a number of pieces of pre-existing anti- discrimination legislation including the Equality Act (Sexual Orientation) Regulations 2007. The Equality Act 2010 prohibits discrimination on grounds of sexual orientation by a public service provider (s29), and then at Schedule 3 para 13 states:

“Blood services

13 (1) A person operating a blood service does not contravene section 29 only by refusing to accept a donation of an individual’s blood if—

(a) the refusal is because of an assessment of the risk to the public, or to the individual, based on clinical, epidemiological or other data obtained from a source on which it is reasonable to rely, and

(b) the refusal is reasonable.

(2) A blood service is a service for the collection and distribution of human blood for the purposes of medical services.

(3) “Blood” includes blood components.”

Paragraph 13 provides that it is not unlawful for a person operating a blood service to refuse to accept someone’s donation of blood provided they have reliable evidence that accepting it would put the public or the individual donor at risk and that such a refusal would not be unreasonable.

This is essentially a rebuttal of the position of some (eg Peter Tatchell) who advocate for the lifting of the ban on all MSM on grounds of “equality”. As the relevant Schedule in the 2010 Equality Act clearly points out, the Blood Donation Service can exclude particular groups of people  normally assured equality rights if it can be shown from “clinical, epidemiological or other data obtained from a source on which it is reasonable to rely” that there is a particular risk inherent in a particular group of people. This of course was the reasoning for the full ban on MSM giving blood originally.

The report then passes quickly over societal changes and moves to the actual clinical evidence as to whether the ban on MSM can be changed and in particular what the effects of that change would be. Here we get to the hard research and the findings are quite interesting.

A small number of studies have looked at the potential impact of changing blood donor selection criteria, however, the majority of these relate to changes to MSM deferrals and do not consider other potential ‘high-risk’ groups. A recent review by Vamvakas argued that there are other infection risks within the blood transfusion services such as exposure to numerous donors ie pooled platelets and donations from first time donors which have not be scrutinised in the same way as MSM deferrals. The author argued that a consistent approach to safety is required when considering donor deferral.

The published modelling studies have estimated the residual risk of an infected blood donation being issued both due to a window period donation being missed and to a false-positive result or a positive result being mistakenly issued following an administrative error. The literature relating to donor deferral mainly considers the risk of HIV infection although one study also looked at the impact of a change to deferral criteria and the risk of an increase in HIV and HBV transmission.

Modelling work carried out in Australia took a different approach looking at the impact of various sexual behaviours on the risk of a donation taking place during the HIV infectious window period. The study looked at a range of sexual behaviours: MSM, heterosexual sex, women who have sex with men from high risk countries, men who have sex with female sex workers and injecting drug users. The model used risk of transmission, frequency of sexual intercourse and prevalence of HIV to calculate the proportion of donors likely to be in the window period at time of donation. MSM were calculated to be at the higher risk but women having sex with men from high-risk countries were also at greater risk than the other populations.

Currently both of these sexual behaviours have a 12 month deferral period in Australia and the authors concluded that if donors comply with the 12 month deferral criteria then the risk of a window-period donation is minimal.

In the UK between 2003 and 2008, the probability of an infectious HIV blood donation not being detected by current testing methods was estimated as 1 in 4 million donations, however the true value could be as low as 1 in 8.3 million or up to 1 in 2.2 million donations. Both Germain et al in Canada and Soldan and Sinka in the UK calculated the residual risk of HIV infection using 1 and 5 year deferral criteria for MSM. The risk of a window-period infection was important in both these models. These two models used different estimates of test errors and false-negative results, the errors used in the UK model being higher due to no HIV NAT testing being used at the time. It should be remembered that these models also make assumptions about the number of MSM who would decide to give blood if donor deferral was changed.

Germain et al calculated that if a 12 month deferral was put in place then an additional 1 infected unit would be issued from every 136,000 new MSM donors; ie a change from 1:1 million to 1:925,000 infected donation with an estimated increase of 1.3% in donations. Soldan and Sinka looked at a number of different scenarios for the UK: the current permanent MSM deferral, a 12 month deferral and no deferral for MSM adjusting compliance to 100% and using the current compliance at that time. Using prevalence and incidence data from 1996-1998 the current HIV residual risk was calculated as 1 per 5.3 million donations for MSM (approximately one infection every two years), for a 12 month deferral this increased to 1 per 1.32 million donations (two per year, 66 % increase in risk) and with no MSM deferral to 1 in 0.95 million (between two and three per year, 458 % increase in risk). The model was also used to assess the residual risk of HIV infection in heterosexual donors who had had sex with someone who had been sexually active in a high risk area for HIV, this residual risk was calculated as 1 per 6.5 million.

This UK modelling work has recently been reanalysed by Davison et al (In press) to take into account changes in testing, most recently the introduction of HIV NAT and the change in estimated prevalence of undiagnosed HIV infection in MSM. This study looks at the residual risk of a HIV infectious donation being released into the blood supply between 2005 and 2007 for a 5 year deferral period. The new model requires an estimate of the number of MSM with and without undiagnosed HIV and has recently been repeated for a 12 month deferral period (Davison et al, in preparation). For fixed period deferrals of either 12 months or 5 years, any incident infections would be due to non-compliance as both are much greater than the current HIV window period whereas an increase in prevalence could have an impact on the number of false-negative reactions and donations erroneously released as negative.

Due to the multiple data sources used in this model the direction of change and relative size of risks are more robust measures than the point estimates. The data for 12 months, 5 years and no deferral are shown in Table 7. A 5 year deferral was estimated to result in a 0.4 – 7.4 % increase in HIV infectious donations being released for transfusion. For a 12 month deferral the increase was 0.5 – 9.9 depending upon the scenario. The modelling suggests that the length of the deferral period is less important than compliance with the rule, with 100 % compliance with either a 12 month or a 5 year deferral reducing the risk by 30 %. The difference in the increase in risk between a 12 month and 5 year deferral was very small unless incidence increased as a result of non-compliance of MSM to the criterion. In terms of the additional risk expected due to the newly eligible MSM, the minimum and maximum increases observed under the different scenarios (0.001 and 0.022 expected extra HIV infectious donations per million) would equate to one additional HIV infectious donation every 455 and 21 years, respectively.

It is of note that these data are based on past observations and since 2007, improvements have been made to HIV blood donation testing. These improvements reduce the length of the WP and if it is assumed that all donations were tested using NAT techniques in minipools (rather than the 56% that were tested this way during 2005 – 2007), the infectious WP would reduce from 10 days to 9 days. Under these circumstances, the estimated HIV risk with no change in incidence/non-compliance would have been reduced by approximately 14 % to 0.195 per million donations.

In a more recent model Anderson et al used a probabilistic simulation approach to assess the risk of an infectious donation being released for transfusion in the US. This study looked at failures in processing and issues considering the effect of a 12 month or a 5 year deferral for MSM. The risks of a failure in blood testing ie a falsely negative result and a contaminated component being falsely released were considered. The risks associated with a window period donation were not considered as it was considered that a 12 month deferral period (assuming compliance) would exclude the possibility of any donor having a window period donation. The model estimated that a 5 year MSM deferral could result in an additional 0.03 HIV infected and an additional 0.004 HBV infected units being released and a 12 month deferral in 0.18 additional HIV infected units and an additional 0.019 HBV infected units per year. In both scenarios, the increased risk arises through an increase in the number of prevalent infections whilst error rates remain unchanged. This would be expected to decrease after the first year of introduction of new donor deferral criteria as new donors with prevalent infections were detected and excluded from further donation.

What does that mean in ordinary words? Well, take careful note of the passages bolded, particularly the passage in red. SaBTO concluded from all the latest research on infection rates and the ability of the Blood Service to screen every donation given to it that by changing the rules to allow all MSM who hadn’t had sex with a man in the past 12 months to give blood, the blood supply could be increased while minimising the risk of passing on HIV to the patient receiving the transfusion. The actual likelihood of an HIV infection through such donated blood would as high as one every 21 years or as low as one every 455 years. Or put another way, by at the extreme margins infecting one person by accident every 21 years with HIV, tens of thousands (if not hundreds of thousands) of people could receive the right kind of blood over that period, possibly saving their lives.

The table below demonstrates what the findings showed. At present approximately 0.227 of every million blood donations results in an HIV infection entering the UK blood bank. The different criteria that could be applied to MSM would affect that figure in the following ways, also exploring whether truthful levels of compliance (i.e. that a man who had sex with a man in the past five years was honest about it) affected the outcome.

HIV Infections per Million Donations (Whole Blood Bank)
No MSM Giving Blood 0.227
MSM >5 Yrs Current Level of Compliance 0.228
Compliance Deteriorates 0.244
100% Compliance 0.161
MSM > 12 Mths Current Level of Compliance 0.228
Compliance Deteriorates 0.249
100% Compliance 0.161
Accept ALL MSM 0.287

Let’s make some sense of this. The current rate of HIV infection across the whole Blood Bank is 0.227 per million donations (or one per 4.41 millions donations). If the rules changed to allow all MSM to give blood, regardless of when they last had sexual contact with someone, the rate of infection across the whole Blood Bank would rise by 26.4%. In anybody’s book this is unacceptable and helps to explain why there was a blanket ban in the first place.

However, changing the absolute ban to MSM but not in the last 5 years has a negligible effect on the overall HIV infection rates. Basically, the new MSM donors would have no higher (or not a significantly higher) chance of accidentally passing HIV into the Blood Bank then the current donors. However, that lack of risk remains the same even when we move down the scale to MSM who haven’t had sex with a man in the past year.

Let’s be very clear about this – There is little added risk of having HIV in the National Blood Bank by changing the ban from all MSM to all MSM who haven’t had sex with a man in the past 12 months. At the same time by including such donors many more pints could be added to the National Blood Stock.

It’s easy to see from this that the SaBTO decision was not based on political pressure or societal mores but rather on hard facts. Indeed, it was the hard facts that prevented them from taking the line that Peter Tatchell and others wanted, namely to lift the ban altogether. Allegations that the ban was lifted simply for political purposes have no substance. What we actually have is a policy change that will provide more blood to be transfused when necessary at little or no extra risk.

If the issue of concern is, quite rightly, to minimise the risk of passing HIV into the national blood stock whilst increasing the level of that blood stock, this move cannot but be applauded as a great first step. Of course, with the barrier now lowered down to just MSM who have had sex in the past 12 months, we begin to enter the area where time periods after HIV infection become important. I can foresee that whilst some may wish to lower the new barrier even further (i.e. to not have an MSM criteria but simply to risk assess on the basis of individual sexual behaviour), this may prove to be harder to achieve as average infection rates (as we have seen above) being to rise rapidly in this sub-group (MSM who have had sex in the past 12 months). Whilst the “window period” for getting an accurate result from an HIV test is falling, the probabilities of achieving false negatives in the first 6 months after infection (i.e. you get a “no” on your test but you are actually infected) are still many times higher then the average HIV infection transfer in the national blood stock (I calculate almost 4000 times higher) and given that we know that the sub-group of MSM who have had sex in the past year have (sadly) a (much) higher HIV infection rate then the rest of the population, these last “12 months” might yet prove to be a group that remain outside of the permitted blood donor population for a long time, certainly until HIV testing makes even greater advancements.

But none of that last paragraph in any way detracts from the simple fact that the changes to the blood donor profiles suggested by SaBTO are a welcome move and may very likely save a number of lives for an insignificant increase in risk. That should be applauded by everybody.

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