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QueerNews版 - 英国将解除对男同性恋者献血的终生禁令
相关主题
UK to Lift Lifetime Ban on Gay Blood Donors1 in 5 Gay Men in Big Cities Have HIV
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China's NGOs spread HIV/AIDS prevention and awarenessAnna Paquin: "I'm Bisexual"
为gay献血问题科普: 黑人献血史:HHS投票决定保留禁止同性恋献血的政策
UK Gay Blood Ban Over?Gay man sues over blood donation in China
Good News, Bad News on AIDS加拿大安省高法决定继续禁止同性恋献血
Warning over HIV tests sold onlinered cross 归来 挺伤感的
再看献血Campaign Windfall for 4 Republicans Who Voted for Same-Sex Marriage
相关话题的讨论汇总
话题: hiv话题: msm话题: blood话题: donors话题: risk
进入QueerNews版参与讨论
1 (共1页)
m******8
发帖数: 2153
1
英国政府即将宣布一项允许男同性恋者献血的新政策,但新规定也要求参加献血的男同
性恋者符合在最近10年里未曾发生过同性性行为的前提条件。
据英国《星期日泰晤士报》4月10日报道,有关新政策将很快由公共卫生部长安妮-
米尔顿(Anne Milton)宣布。政府方面认为,终生禁止男同性恋者献血的原有政策可
能违反英国《平等法》中的禁止歧视条款。
相当于终生禁止男同性恋者献血的原规定是出于防止艾滋病毒感染等方面的血液安
全考虑而作出。有数据显示,英国的HIV感染者总数约有86500人,其中男同性恋者占42
%,异性恋者则占54%。
尽管存在现有规定,但据估计仍有约7%的性活跃男同性恋者参加过献血,有关规定
的执行主要凭献血者自我约束。英国的血液机构会对捐献来的血液进行HIV等项目的检
测,但由于HIV病毒感染后在一定的“窗口期”内无法被有效检测,因而仍可能会有极
少量的被感染血液进入血库。
英国的血液安全、组织与器官事务咨询委员会(SaBTO)经过研究和评估后认为,
如果将男同性恋者献血的前提定为最近五年之内未曾有过同性性行为,被感染血液进入
血库的风险将增加5%,如果将这一前提的时间跨度定为十年,则有关风险将只增加2.5%。
近年来,一些团体和人士一直呼吁取消对男同性恋者献血的终生禁令,认为许多男
同性恋者并没有不安全的性行为,献血禁令不应针对性倾向,有关规定是对同性恋者的
歧视。
据报道,对于新政策,英国政府表示,完全的禁止是不公平和歧视性的,但也需要
保护公共健康,因此放宽了有关规定,在“十年前提”下允许男同性恋献血。新的政策
将与其它一些国家有条件的准许男同性恋者献血的规定相似。(爱白网)
m******8
发帖数: 2153
2
HIV+ population ratio straight:gay~=1:1, risk ratio~=1:1, so this ten year
rule, which is not applied to straight, is still too strict for gay
population
m******1
发帖数: 19713
3
不能这么说,gay只占人口的6%,感染HIV的绝对人数就已经和直人接近1:1了,这个数
字还是挺惊人的。

【在 m******8 的大作中提到】
: HIV+ population ratio straight:gay~=1:1, risk ratio~=1:1, so this ten year
: rule, which is not applied to straight, is still too strict for gay
: population

m******8
发帖数: 2153
4
技术上讲,HIV检测不用十年.统计上讲,让gay献血增加的风险也很小.这样的政策仅是向
征性, 没多大实际意义.
g********d
发帖数: 4174
5
关于献血,本版以前有很多讨论。不过没有讨论10年限制的具体意义,这个政策应该是
有数据支持的,不会只是象征性的。

【在 m******8 的大作中提到】
: 技术上讲,HIV检测不用十年.统计上讲,让gay献血增加的风险也很小.这样的政策仅是向
: 征性, 没多大实际意义.

m******8
发帖数: 2153
6
http://en.wikipedia.org/wiki/MSM_blood_donor_controversy
The reference 22 is just a news article... not sure how this risk was
calculation and how such policy was made... practically still banned for
gays...
========================
10 year gay blood ban is unjustified
Posted by Peter Tatchell - 12 April 2011 17:00
A change of policy to include the HIV virus test alongside the antibody test
would be safer, smarter and free up more much-needed blood.
A nurse performs a simple HIV antibody test (Getty Images)
According to the Sunday Times (£), the government is planning to lift
the blanket, lifetime ban on blood donations from men who have had oral or
anal sex with men. This ban was introduced at the height of AIDS panic in
the 1980s, on the grounds that gay and bisexual men are at greater risk of
HIV. The public health minister Anne Milton is reportedly planning to modify
the ban. Men who have had sex with men will be no longer be barred for life
, but only for 10 years after the last time they had oral or anal sex. This
ban will apply even if they always use a condom and even if they test HIV-
negative.
A 10 year ban is too long. So is five years or even one year. These are
needlessly cautious exclusion periods. Protecting the blood supply is the
number one priority but ensuring blood safety does not require such lengthy
time-spans during which gay and bisexual men should not donate blood.
The blood service could replace the blanket lifetime ban on blood donations
from gay and bisexual men with a much shorter exclusion period. It should
focus on excluding donors who have engaged in risky behaviour and those
whose HIV status cannot be accurately determined because of the delay
between the date of infection and the date when the HIV virus and HIV
antibodies manifest and become detectable in an infected person's blood.
HIV antibodies normally take a maximum of one to three months to become
identifiable in lab tests. The HIV virus can take two weeks to be detected.
The blood service currently tests all donated blood for HIV antibodies but
not for the HIV virus. To be safe, perhaps it should do both tests on
potentially risky blood donations?
Reducing the exclusion period for blood donations from gay and bisexual men
should go hand-in-hand with a "Safe Blood" education campaign targeted at
the gay community, to ensure that no one donates blood if they are at risk
of HIV and other blood-borne infections due to unsafe sexual behaviour.
Moreover, the questionnaire that would-be blood donors have to answer should
be made more detailed for men who have had sex with men, in order to more
accurately identify the degree of risk - if any - that their blood may pose.
There is, in addition, a strong case for only excluding men who have had
risky sex without a condom. At the moment the blood service makes no
distinction between sex with a condom and sex without one. All oral or anal
sex between men - even with a rubber - is grounds for refusing a donor under
the current rules. This strikes me as odd. If a condom is used correctly,
it is absolute protection against the transmission and contraction of HIV.
Those who use condoms every time and without breakages should not be barred
from donating blood.
In contrast to the suggested 10 year ban for gay and bisexual blood donors,
a six month exclusion period would be sufficient. This would exclude male
donors who have had oral or anal sex with a man without a condom in the
previous six months. All men who last had unprotected sex with men more than
six months ago would have their blood tested for HIV antibodies, as is the
current practice. Although the six month exclusion period is more than twice
as long as it takes HIV antibodies to appear in the blood of an infected
person, this is may be justified to err on the side of caution and to
reassure the public.
The exclusion period could, however, be much shorter than six months, with
certain provisos. The blood service could decide to ban only donations from
men who have had unsafe, condomless oral or anal sex with a man in the last
month. For men who have had unprotected oral or anal sex with a man in the
preceding one to six months, the blood service could be extra safe and do
both a HIV antibody test and a HIV virus test on their blood. Since the HIV
virus shows up in blood tests within two weeks of the date of infection, the
one month total exclusion period offers a double-length margin of safety.
This would guarantee that the donated blood posed no risk to its recipients.
A change of policy along either of the afore-mentioned lines would not
endanger the blood supply. With the specified safeguards, the blood donated
would be safe.
The call for change is growing worldwide. The American Red Cross, the
American Association of Blood Banks and America's Blood Centres favour
ending the lifetime ban on gay and bisexual men donating blood.
According to Dr Arthur Caplan, former Chair of the US Government Advisory
Panel on Blood Donation: "Letting gay men give blood could help bolster the
supply. At one time, long ago, the gay-blood ban may have made sense. But it
no longer does."
The truth is that most gay and bisexual men do not have HIV and will never
have HIV. Both the lifetime and 10 year bans are driven by homophobic,
stereotypical assumptions, not by scientific facts and medical evidence. For
the vast majority of men who have sex with men, their blood is safe to
donate. Far from threatening patient's lives, they can and should help save
lives by becoming donors.
...http://www.newstatesman.com/blogs/the-staggers/2011/04/blood-ban-gay-sex-hiv-test
g********d
发帖数: 4174
7
James
13 April 2011 at 00:47
"Research shows that completely removing the current exclusion on blood
donation from men who have sex with men would result in a fivefold increase
in the risk of HIV-infected blood entering the blood supply. While changing
deferral to one year from the last sexual contact would have a lesser effect
, it would still increase this risk by 60%.
Soldan K & Sinka K – Vox Sanguinis (2003) 84, p265-273"
This isn't a discrimination issue. Health policy shouldn't be made into
a political issue, and neither should it pander to rights groups, it should
be led by the best scientific evidence available.
Diagnostic tests for HIV are prohibitively expensive in terms of testing
all blood donations. As such, the most safe and affordable way is to
eliminate certain groups which are statistically higher risk. This includes,
but is not limited to, homosexual males.
g********d
发帖数: 4174
8
我们要看的支持和反对10 yr ban的计算。外行的车轱辘转的话没有什么说服力。
m******8
发帖数: 2153
9
Donated blood should be required to follow WHO's recommended screening tests
including HIV-1/2 antibody test, since majority blood is eventually sold to
patients. What's the point of donating things to be sold by others? Where
are the patients' rights to receive disease-free blood? What do those policy
makers think?
S***e
发帖数: 4426
10
i think the ten-year rule has nothing to do with discrimination.
我觉得歧视是指根据人的属性(比如年龄、性别、国籍、宗教、性取向等等)来区别对
待。
而根据人的行为区别对待并不算歧视。
这个十年的规定就是根据行为的。异性恋也可以有同性的性行为,一样会被禁止献血。
至于十年是不是科学,就是另一个问题了。

【在 m******8 的大作中提到】
: HIV+ population ratio straight:gay~=1:1, risk ratio~=1:1, so this ten year
: rule, which is not applied to straight, is still too strict for gay
: population

g********d
发帖数: 4174
11
Evaluation of the de-selection of men who have had sex with men from blood
donation in England
K. Soldan1,2, K. Sinka1,*
Keywords:blood donors;donor selection;HIV;transfusion-transmitted infection
Abstract
Background and Objectives The Blood Services of the UK permanently de-select
men who have had sex with men (MSM) from donating blood. The rationale for
this has been questioned. This article attempts to evaluate whether this
selection criterion does contribute to blood safety.
Materials and Methods Data about transfusion-transmissible infections, in
particular about human immunodeficiency virus (HIV) infection, were used to
evaluate whether de-selection of MSM meets the aims of donor selection.
Models were constructed to estimate the risk of HIV-infectious donations
entering the blood supply should this criterion be changed.
Results Many assumptions were required to generate estimates of the risk of
HIV infection entering the blood supply. The accuracy of the estimates is
therefore uncertain and the probable ranges around the estimates were wide.
However, by using the most probable assumptions, our models suggested that
de-selection of MSM for 12 months since the last sexual contact, or complete
removal of this selection criterion, would be expected to increase the risk
of HIV-infectious donations entering the blood supply in England by
approximately 60% (from the current risk of 0·45 per year to 0·75 per year
) and 500% (to 2·5 per year), respectively. The increase in numbers of non-
infected donations would be relatively small – less than 2% of donations.
The probability of a relatively high frequency of other sexually
transmissible blood-borne infections also currently favours maintaining
permanent de-selection of MSM, irrespective of the risk of HIV-infectious
donations. Current compliance with this selection criteria was estimated to
be 95%.
Conclusions Based on current knowledge, accepting blood donations from MSM
would probably increase the risk of transfusion–transmission of HIV and of
other blood-borne infections. Good compliance with this criterion has
contributed greatly to the safety of blood transfusions in England. Better
communication about donor selection, to maintain and improve compliance with
this and other selection criteria, is recommended. Other risk groups are
gaining in relative importance for the risk of transfusion-transmitted HIV
infection, and ongoing evaluation of all donor-selection criteria is also
recommended.
g********d
发帖数: 4174
12
Jump to…Top of pageAbstractIntroductionMaterials and
methodsResultsDiscussionConclusionAcknowledgementsReferences
Introduction
Top of page
Abstract
Introduction
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References
The National Blood Services of the UK have, since the early 1980s, asked men
who have ever had sex with men (MSM) to not donate blood. At first, this
action was motivated by the aim of preventing transmission by transfusion of
the infectious agent associated with acquired immune-deficiency syndrome (
AIDS) [subsequently identified as human immunodeficiency virus (HIV)]. This
donor-selection criterion is now worded:
You must NEVER give blood if you are a man who has had (anal or oral) sex
with another man (even safer sex using a protective).
The present article is a review of the current purpose and probable
performance of this criterion. Epidemiological data have been reviewed and
used to estimate how much the permanent de-selection of MSM reduces the risk
of donations that are infectious for HIV entering the blood supply. The
estimated reduction is compared to that expected for alternative criteria
with respect to MSM, and to that expected for another criterion relating to
donors with an increased risk of heterosexually acquired HIV.
Jump to…Top of pageAbstractIntroductionMaterials and
methodsResultsDiscussionConclusionAcknowledgementsReferences
Materials and methods
Top of page
Abstract
Introduction
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References
Review of epidemiological data from donors and other sources
Data about the frequency of transfusion-transmissible infections (TTIs) in
donors – as identified by donation testing – and about probable routes of
infection for these donors was obtained from surveillance systems of the
National Blood Service and of the Public Health Laboratory Service
Communicable Disease Surveillance Centre (PHLS CDSC) (which conducts follow-
up for missing information). The contribution that sex between men has made
to the total prevalence and incidence of infections in collected blood
donations over the years was determined.
Other data about blood-borne infections were reviewed to determine whether
MSM have been shown to be associated with an increased risk of acquiring
other sexually transmitted blood-borne infections.
Recent reviews of the current understanding of the risks of oral sex and of
sex using a protective were consulted.
Estimation of the risk of HIV-infectious donations entering the blood supply
Estimates of the frequency of HIV-infectious donations entering the blood
supply in England have previously been described in full [1]. In brief,
these estimates include: calculation of the risk of collecting a donation
from someone who has recently been infected and has not yet developed
detectable HIV antibodies (anti-HIV), i.e. a window-period donation; and
calculation of the risk of an anti-HIV-positive donation not being removed
by donation testing owing to the fallibility of laboratory tests (as no test
is 100% sensitive) and the probability of an error in the sampling and
testing process allowing mistaken release of a positive donation. The risk
of the former was calculated from the incidence of infection and the length
of the window period (15, i.e. 22 days of a serology-negative window [2]
minus 7 days of non-infectivity immediately after infection). The risk of
the latter was calculated from the prevalence of infection, the sensitivity
of tests in use (99·9%) [3] and the error rate in the testing process (0·5
%, based on published estimates of error reported for the USA) [4–6]. The
incidence in repeat donors was estimated from observed seroconversions. The
incidence in new donors was estimated as that in repeat donors multiplied by
2·29 – an adjustment factor to correct for the increased infection rates
in new donors [1]. The probability of infectious donations entering the
blood supply was calculated for donations from new donors and for donations
from repeat donors separately, and finally combined in the ratio of all
donations collected (89% repeat, 11% new).
These calculations of the risk of HIV-infectious donations entering the
blood supply from all donors were run for three scenarios:
A. With permanent de-selection of MSM (i.e. current).B. With a change to
accept MSM 12 months after last MSM sexual contact (i.e. 12-months).C. With
a change to accept all MSM (i.e. no de-selection).Because compliance with
the current criterion of permanent de-selection is not complete, and it has
been suggested that compliance with a 12-month criterion might be better
than it is with permanent de-selection, scenarios A and B were run once with
an assumption of currently observed compliance rates and once with an
assumption of complete compliance.
Since 1995, all blood centres in England have participated in a system for
the surveillance of TTIs run by the PHLS CDSC and the National Blood Service
. The prevalence and incidence of HIV in blood donors attending during 1996
–98 were calculated from these surveillance data for use in scenario A. The
expected prevalence and incidence of HIV, assuming compliance with the MSM
criterion was complete, was estimated by excluding anti-HIV positives, with
sex between men reported as their probable route of infection from the
numbers used for these calculations. For scenarios B and C, estimates of the
prevalence and incidence of HIV infection in MSMs and in the whole
population of accepted blood donors if MSMs were accepted – only after 12
months, or unconditionally – were made as described below.
Estimation of prevalence of HIV in MSM
The prevalence of undiagnosed HIV infection in MSM who have had sex within
the past 12 months (active-MSM) was taken to be that observed in those
attending the Unlinked Anonymous testing of Genitourinary Medicine clinic (
UA-GUM) [7]. The total number of these active-MSM in the population was
estimated by combining estimates of the mid-1999 16–64-year-old male
population [8] with the proportion of males reported by the National Survey
of Sexual Attitudes and Lifestyles (NATSAL) (in the early 1990s) to have had
some homosexual experience involving genital contact during the past year [
9]. The number of undiagnosed HIV infections amongst active-MSM was then
calculated by applying the prevalence of undiagnosed infections (from UA-GUM
data) to the estimated total number of currently active-MSMs.
The number of individuals with prevalent undiagnosed HIV infections (alive
at the end of 1998), probably acquired by sex between men, was obtained from
published work [10] that used data about subjects with diagnosed infections
receiving care, from behavioural surveys and from the unlinked anonymous (
UA) programme, and this number was estimated to be 4500 [7].
The number of undiagnosed HIV infections in MSM who had not had sex with men
within the past 12 months was then calculated by subtracting the active-
MSMs from the total estimate of undiagnosed infections in MSM. Prevalence in
this group was calculated using this number and the total number of
individuals in this group, which was derived from the proportion of males
reported by NATSAL as having had sex with men (but not in the past year) and
the mid-1999 population estimate.
The frequency of blood donors amongst males aged 16–64 years was derived
from population estimates and the number of registered male donors in this
age group (A. Oliver, National Blood Service; personal communication). It
was assumed that MSM would become donors (if not de-selected) at the same
frequency as 16–64-year-old men who were not MSM.
The numbers of additional anti-HIV-positive donations that would be
collected in scenarios B and C were calculated by applying the relevant
estimate of HIV prevalence to the number of MSM who would be expected to
give blood in those scenarios. These additional HIV-positive donations were
added to the number observed by donation testing during 1996–98 to
calculate the expected prevalence of HIV amongst all blood donations for
each scenario.
Estimation of incidence of HIV in MSM
The incidence of HIV in MSM, but who had not had sex with men within the
past 12 months, was assumed to be zero. During 1996–98 there were –
despite the donor-selection criteria in place – new HIV infections in
donors who were reported as probably infected as a result of sex between men
. Scenario B was run once with an observed HIV incidence in donors (i.e.
current compliance) and once assuming that the change to a 12-month de-
selection would result in complete compliance with the MSM de-selection, and
therefore using the incidence in donors as calculated after excluding
observed new infections from MSM.
The incidence of HIV infection in MSM who had had sex within the past 12
months was estimated as follows. First, it was assumed that MSM who do not
currently give blood, but would if not de-selected, have the same prevalence
and incidence of HIV infection as MSM who have given blood (i.e. have not
complied with de-selection). The number of MSM who donated during 1996–98
was derived from the prevalence of HIV infection in MSM (from above) and the
observed number of HIV-positive donations detected during 1996–98 from MSM
. This denominator of MSM current donors was then used (together with an
estimate of donation frequency) to give person-years observed, and with the
observed number of seroconverting donors who were MSM during 1996–98, to
estimate the incidence of HIV amongst MSM who currently donate blood. This
incidence was assumed to apply to the population of active-MSM who were
expected to donate if not de-selected, and the number of additional
seroconversions expected was calculated.
As the values of many parameters used in these prevalence and incidence
estimates differed significantly for London compared to locations outside
London, the calculations were performed separately for London and locations
outside London, and the number of additional HIV infections finally combined
to a single figure for use in the national risk calculations.
Meaningful confidence intervals were not available for many of the
assumptions and estimates used to calculate the risk estimates. Owing to
this, no error bands or probable ranges were constructed for the risk
estimates. Previous work has found that the probable ranges around the
estimates, when using observed incidence and prevalence, range from
approximately 66 to 190% of the point estimate [1]. The probable ranges
around the risk estimates for scenarios that incorporate additional
assumptions and derived prevalence and incidence, are expected to be wider.
Sensitivity analyses
For most parameters, any variation, or error, in the values used would
change the results in a similar direction in all scenarios, and the
sensitivity of the estimates to these parameters was not considered. There
was one parameter – compliance – for which this was not necessarily true,
and there could be variation depending on the scenario. Results for
scenarios A and B with current compliance and with 100% compliance were
plotted and, by assuming the relationship between risk and compliance was
linear within each scenario, the point at which better compliance with B
could result in a risk estimate equivalent to that for A was deduced.
Current compliance was calculated by dividing the estimated number of MSM
who currently donate by the estimated number of MSM who would donate if not
de-selected.
Comparative value of another criterion
For comparison, the HIV-risk calculations were also run for two scenarios
that related to another criterion also stated on the Safety of Blood leaflet:
You should not give blood for a year after sex with anyone, of any race, who
has been sexually active in Africa in the past year
The two scenarios are as follows:
D. Permanent de-selection of individuals who have had heterosexual sex in
Africa, or with a partner who has been sexually active in Africa, andE.
Complete compliance with current de-selection for 12 months of these
individuals.For these two scenarios, the fall in the number of anti-HIV-
positive donations and in the number of seroconversions amongst donors, that
would be expected, was taken directly from observed data about anti-HIV-
positive donors detected during 1996–98, i.e. the observed number of anti-
HIV-positive donations from donors who reported sex in Africa, or with a
partner from Africa, as their probable route of infection.
g********d
发帖数: 4174
13
Results
Top of page
Abstract
Introduction
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References
Review of epidemiological data from donors and other sources
The prevalence of anti-HIV in blood donors is very low. Both the number and
the proportion of anti-HIV-positive donors, reported as MSM, have fallen
over the years (Fig. 1). However, this route of infection still constituted
approximately 27% of anti-HIV-positive donations during 1998–2000. Sexual
intercourse between men and women has become relatively more important as a
route of infection for blood donors, with the majority of infections in
recent years falling into this category. Fifteen per cent of heterosexually
infected donors probably acquired their infections by sexual contact with
someone who had been sexually active in Africa (36 (9%) infections were
acquired in Africa and 25 (6%) were acquired in the UK).
Figure 1. Probable routes of infection for anti-human immunodeficiency virus
(HIV)-positive donors detected in England and Wales. Donations collected
from 01/10/85 to 31/12/2000 (in 3-year periods).
The incidence of HIV infection has also been low amongst blood donors.
Twenty-seven seroconversions for anti-HIV were observed in repeat donors
during 1996–98, resulting in an estimated incidence of 0·54 per 100 000
person-years. Sex between men was reported as the probable route of
infection for nine (33%) of these infections, and sex between men and women
for 16 (59%) (four (15%) reported sex with a partner in/from Africa).
Other risk factors predominate amongst hepatitis B virus (HBV)- and
hepatitis C virus (HCV)-infected donors, as for these infections amongst
other population groups: sex between men has been reported to account for <
1% of hepatitis B surface antigen (HBsAg)- or anti-HCV-positive donors.
Review of other data shows that MSM are at higher risk of most infections
that can be sexually transmitted – including known TTIs such as herpes
simplex virus (HSV) [11], human herpesvirus 8 (HHV8), HBV and hepatitis A
virus (HAV) – than heterosexual men and women [12]. There is also evidence
that the effects of behavioural modifications (strongly promoted in the
1980s) have not been maintained and that high-risk behaviours, and infection
transmission, continues amongst MSM. In a review of trends in sexually
transmitted infections (STIs) in the UK between 1990 and 1999, it was found
that the diagnosis of many acute STI (including infectious syphilis,
uncomplicated gonorrhoea, genital chlamydial infection and genital warts)
has been rising amongst MSM in UK since 1995 [12]. Amongst some groups of
MSM, high-risk behaviours appear to be increasing [13].
The Expert Advisory Group on AIDS (EAGA) recently issued the following
statement [14]:
There is a risk of HIV transmission during unprotected oral sex. This risk
is less than that from unprotected anal or vaginal sex. The risk of HIV and
other STIs can be reduced, but not eliminated, by using a condom for all
forms of penetrative sex, including oral sex.
While sex with a protective reduces the risk of infection transmission,
condom failures are well documented – both relating to pregnancy and to
sexual transmission of infections [15]– and their use is not considered to
remove all risk [16].
Prevalence and incidence of HIV in MSM
The parameters and values involved in estimation of the number of additional
HIV-infected donations that would be collected if MSM-past and active-MSM
were accepted as blood donors, are shown in Table 1.
Table 1. Estimation of additional human immunodeficiency virus (HIV)-
infected donations that would be collected (probably during the first year)
if active-MSM and MSM-past were accepted as blood donors London Outside
London England and Wales
MSM, men who have had sex with men.
Male population 16–64 years old 2 637 895 14 834 197
Donor panel 16–64 years old 94 923 767 149
Percentage of male 16–64 population who are donors 3·6% 5·2%
Percentage and number of males who are active MSM 3·6% 0·7%
(i.e. have had sex with men in the past 12 months) 95 341 106 065
Percentage and number of males who are MSM but 4·9% 2·2%
who have not had sex in the past year (MSM-past) 128 880 321 160
Prevalence of undiagnosed HIV in active MSM 2·8% 0·5%
Prevalence of undiagnosed HIV in MSM-past 0·84% 0·07%
Prevalence of undiagnosed HIV in all MSM 1·67% 0·17%
Number of undiagnosed HIV-positive active MSM donors, if accepted 96 27 123
Number of undiagnosed HIV-positive MSM past donors, if accepted 39 11 50
If we assume that these infected donors would donate during the first year
of acceptance as donors, the prevalence of anti-HIV amongst all blood
donations would increase from 0·89/100 000 to 2·93 per 100 000 (i.e. a
threefold increase) in scenario B, and to 7·94/100 000 (i.e. a ninefold
increase) in scenario C.
The parameters and values involved in estimation of the number of additional
HIV seroconversions that would be observed amongst donors if MSM were
accepted as blood donors, are shown in Table 2.
Table 2. Estimation of additional human immunodeficiency virus (HIV)
seroconversions that would occur amongst blood donors if active-MSM were
accepted as blood donors London Outside London England and Wales
aThe prevalence of undiagnosed anti-HIV in MSM divided by the number of anti
-HIV-positive MSM donors, i.e. 0·0167 ÷ 4·67.
bApproximately one donation every 0·8 years is used to estimate person-
years at risk.
MSM, men who have had sex with men.
Number of anti-HIV-positive donations collected per year from MSM (observed
1996–1998) 4·67 2·33
Number of anti-HIV seroconversions observed in MSM donors per year (nine
observed 1996–1998) 2 1
Number of MSM who donate (assuming the prevalence of undiagnosed HIV given
in Table 1)a 279 1337
Percentage of male 16–64-year-old donors 0·29% 0·17%
Observed incidenceb of HIV in MSM donors (% per year) 0·83% 0·09%
Expected additional seroconverters per year if active-MSM were accepted 25 4
29
Estimation of the risk of HIV-infectious donations entering the blood supply
The effect that these expected increases in HIV-positive donations and
seroconversions in donors would have on the estimated risk of an infectious
donation (from all donors) entering the blood supply is shown in Table 3.
Table 3. Estimated risk of human immunodeficiency virus (HIV) infectious
donations being released into the blood supply Scenario One infectious
donation per X million issued Infectious donations issued per year
Percentage of baseline risk Percentage change in donors
aActive-MSM, MSM within the past 12 months.
bHetero-SA, individuals who have had heterosexual contact with the high HIV
endemicity of sub-Saharan Africa.
MSM, men who have had sex with men.
Baseline:
A. Current MSM criterion 5·3 0·45 100% –
Changes to MSM de-selection:
Current with complete compliance 7·9 0·30  67% −0·09%
B. De-selection of active-MSMa with current compliance 3·2 0·75 166% +1·
17%
De-selection of active-MSM with complete compliance 4·5 0·53 118%
C. No de-selection of MSM 0·95 2·5 558% +1·66%
Changes to Hetero-SAb de-selection:
D. Hetero-SA-permanent de-selection 6·5 0·37  82% Not known
E. Hetero-SA-current with complete compliance 7·4 0·32  71% Not
known
The initial increase in risk in scenarios B and C would be expected to
decrease somewhat over time as the newly included donors with prevalent HIV
infection were identified and excluded from donating. The component of the
increase in risk as a result of increased incidence would be expected to
continue.
Sensitivity analysis
If compliance with permanent de-selection (scenario A) were to fall below 90
%, the point estimate of the risk of HIV associated with a 12-month de-
selection (scenario B) could – if 100% compliance were achieved with this
– be equivalent, or lower. Current compliance was estimated as 95%[1 – (
1616 ÷ 30 287)]: at this high level of compliance with permanent de-
selection, the point estimate of the risk associated with 12-month de-
selection was never lower, even at the point of 100% compliance with 12-
month de-selection.
Comparative value of another criterion
During 1996–98, 12 anti-HIV-positive donations were collected from donors
for whom sex in Africa, or with a partner from Africa (but not in Africa),
was reported as their probable route of infection. Four of these
seroconverted for anti-HIV between donations. For 50% of these anti-HIV
positives, for which a year of exposure was known, the last exposure had
been within the 12 months prior to their anti-HIV-positive donation. The
results of excluding these donors from the data entering the risk model are
also shown in Table 3.
Jump to…Top of pageAbstractIntroductionMaterials and
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Discussion
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Abstract
Introduction
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References
Aims of donor selection
At first, the criteria used to select blood donors were specifically aimed
to select donors at a low risk of HIV infection. More recently, particularly
since experience with HCV [16,17], the aim has been to select blood donors
who are at low risk of all TTIs, including both TTIs for which blood is
tested and TTIs for which blood is not currently tested.
Testing of blood donations does not entirely remove the risk of infectious
donations entering the blood supply, or even remove it sufficiently for
donor-selection criteria, related to these infections, to be unimportant. As
long as there are marker-negative windows during infection, and the testing
process is fallible and does not address all infections that may harm
recipients, both the incidence and the prevalence of blood-borne infections
in blood donors remain important. It may be that infections which are not
currently tested for – some currently unknown – are those that pose the
most danger to blood recipients. Individuals exposed to an increased risk of
acquiring known blood-borne infections are expected – in the absence of
direct information – to have relatively high prevalence and incidence of
unknown blood-borne infections and therefore are asked to not give blood. De
-selection for 12 months aims to avoid donation during the early stages of
infections when blood-borne infectivity is more common, and to avoid
donations from individuals with frequent exposures. Maintaining an adequate
blood supply (of all blood groups) is also an aim, and this means that
permanent de-selection of some behavioural groups (or ethnic groups) is not
feasible. Finally, criteria aim to be clear and specific, and so be easy to
use without requiring detailed recall or discussion. Further review of
particular individuals’ circumstances may follow if space and time permits.
The balance of these sometimes conflicting aims is dynamic and can change
within the UK over time and between different countries.
Estimates of the probability of HIV-infectious donations from MSM entering
the blood supply
Risk estimates, of the type used here, are increasingly being used to
monitor blood safety and evaluate new strategies for reducing the risk of
TTIs [18–20]. The assumptions used were considered the most probable given
current knowledge, but there is uncertainty in a number of the assumptions
used. For example, we assumed that GUM attenders are representative of ‘
active-MSM’. It seems probable that GUM attenders would be of higher risk
than non-attenders and the prevalence in active-MSM may therefore have been
overestimated. However, it has been estimated that a high proportion – 42%
– of gay men (recruited at gay venues) in London had attended a GUM clinic
during the past year (J. Dodds, personal communication). The same study
reported a prevalence (of 3·7%) of undiagnosed HIV amongst MSM who had not
attended a GUM clinic – higher than the 2·8% observed in the unlinked
anonymous GUM sample from London and used in the present study as the active
-MSM prevalence. If prevalence in this group was overestimated, then
prevalence in the MSM-past will, by subtraction, have been underestimated (
assuming that the estimate of total undiagnosed infections in MSM was
correct).
Our assumption, that MSM who currently donate are at equal risk of HIV
infection as MSM who do not currently donate, may mean that we have
underestimated the HIV incidence amongst all MSM who would donate if
accepted (and therefore underestimated the increased risk associated with
that scenario). A study of UA samples from MSM attending GUM clinics (
assumed to represent active MSM) estimated the incidence of HIV infection to
be considerably higher: 3·8% in London and 2·1% outside London [21].
Although not calculated, it is certain that the probable ranges around the
estimates were wide compared with the differences between the scenarios. The
point estimates should not be over-interpreted, or considered to be precise
quantifications of risk. However, inaccuracies in the parameters used would
not – in most cases – affect the relative advantage of the evaluated
scenarios.
Compliance
A US study that asked donors – after donation – to complete a confidential
questionnaire about their risk behaviours found that 0·57% of male donors
reported sex between men, which should have excluded them from donating
blood [22]. Our calculated estimate that 0·19% of current male donors are
MSM is broadly consistent with, but slightly lower than, the US observation,
suggesting either better compliance with donor selection in the UK or a
higher prevalence of sex between men in the USA.
We do not know whether compliance would improve or worsen if the criterion
was changed. However, we found that no possible improvement in compliance
could compensate for the expected increased frequency of HIV infection in
donors if the MSM criterion was changed.
Prevention of other TTIs
The risk of as-yet unidentified infections justifies the use of generic
measures to limit the risk of infection to which recipients are exposed:
these include measures to avoid unnecessary transfusion; the avoidance of
donation pooling (i.e. minimizing the number of donors to which a recipient
is exposed); the recruitment of non-remunerated donors; and the de-selection
of donors believed to be at increased risk of blood-borne infections.
MSM were found to be at increased risk of most STIs. The blood-borne viral
infections that pose the greatest danger to blood recipients have long,
asymptomatic, infectious (via blood) periods before they cause disease in
their host. These characteristics tend to be selected for in organisms that
are transmitted sexually.
Comparison with other selection criteria
The criterion relating to heterosexual sex with partners from countries with
a high HIV prevalence (simplified here to countries of sub-Saharan Africa)
primarily aims to avoid the collection of donations during the early marker-
negative period of HIV infection. There are few data that allow direct
comparison of the frequency of HIV infection in these individuals and in MSM
. The prevalence of undiagnosed HIV infection amongst heterosexuals, born in
sub-Saharan Africa, attending GUM clinics in England, Wales and Northern
Ireland during 1998–99, has been estimated as around 1·7% in London,
compared with 2·8% in MSM. Our HIV estimates suggest that there would be
reduction to the baseline risk of HIV if these donors were de-selected
permanently. With respect to other infections, there are insufficient data
to demonstrate that heterosexual sex in Africa, or with a partner from
Africa, is a significant risk factor for STIs in the UK, in general. A study
of GUM clinic patients found that the incidence of gonorrhoea in 1996 was
812 per 100 000 in homosexual males, 467 per 100 000 in black Caribbeans,
235 per 100 000 in black Africans and 22 per 100 000 in white people [23],
and concluded that homo/bisexual men and the black-Caribbean population in
England experience a disproportionate burden of gonococcal infections. Other
studies have also identified the Caribbean population in London to be at a
higher risk of STIs [24]. Although potentially important for future
improvements to donor selection, these observations about geographical
variations in STI risk amongst heterosexuals are neither as strong, or as
consistent, as for MSM. Permanent de-selection of groups of donors by
geography effectively de-selects some ethnic groups. Several blood groups (
Ro, Fy(a- b-) and S- s- U-) are very rare amongst Caucasians and Asians, but
common amongst Black ethnic groups, and are needed to provide transfusion
for patients with these blood groups. There is currently little margin
between collection of and demand for several rare blood groups, and a
decrease in the numbers of Black-African donors would threaten the supply of
these components. Donor selection must consider this as well as the risk of
HIV or other infections.
Avoidance of accepting donations from donors with heterosexually acquired
infections is harder than from MSM because individuals do not always know
their partners’ risk factors, and so full compliance is not possible. This
goes some way to explaining the rise in the relative frequency of donations
from heterosexually HIV-infected individuals over the years.
Jump to…Top of pageAbstractIntroductionMaterials and
methodsResultsDiscussionConclusionAcknowledgementsReferences
Conclusion
Top of page
Abstract
Introduction
Materials and methods
Results
Discussion
Conclusion
Acknowledgements
References
To the best of our knowledge there is currently more benefit to patients
from reducing the numbers of HIV-positive MSM men who give blood, than from
increasing the numbers of HIV-negative MSM men who may give blood.
Permanent de-selection of groups known to be at high risk of blood-borne
infections – currently MSM, intravenous drug users (IDUs) and commercial
sex workers – is expected to improve the safety of blood with regard to
other infections. This effect has not been estimated, but remains important,
irrespective of the risk of HIV infection.
Relaxing this criterion to a 12-month de-selection, or to no de-selection,
is expected to increase the risk of HIV transmission by transfusion by
approximately 60% and 500%, respectively, – at least in the first year.
This would be the cost of an increase in donor numbers of less than 2%.
Uncertainty in the assumptions used for these HIV estimates means that a
wide range of outcomes cannot be definitely excluded. However, the
likelihood of a benefit from a 12-month deferral appears to be very low.
Better compliance on its own, without moving to 12-month de-selection, would
certainly be more beneficial.
The current MSM criterion is estimated to improve the HIV-related safety of
blood by preventing the release of one HIV-infectious blood donation every 3
years when compared to 12-month de-selection, or one HIV-infectious
donation every 6 months when compared to no de-selection. The excellent
compliance of most MSM with this selection criterion over the past two
decades has undoubtedly prevented many transmissions of HIV by blood
transfusion in England.
g********d
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