EDITORIAL
Technical solutions to social issues?
T
here has always been a social dimension to infec-
tious disease, but this was not really a focus in
transfusion medicine until the emergence of
HIV/AIDS. HIV infection and AIDS were feared
due to an invariably fatal outcome for which various demo-
graphic and behavioral groups were deemed to be at ele-
vated risk, leading inevitably to the construct of “risk
groups.” To be in a risk group was devastating; not only was
it a potential death sentence, but it also was socially sensi-
tive and potentially demeaning. The intersection of risk and
transfusion medicine involved the need to assure patient
safety while facing issues of sexual and other risk behaviors
among individuals presenting to give blood. Eventually, reg-
ulators in the United States and internationally established
requirements that, in effect, resulted in the indefinite defer-
ral of risk group members from donating blood. A primary
risk group in the United States was (and still is) men who
have had sex with men (MSM), who were until recently
deferred if they acknowledged having had sex, even once,
with another man since 1977. That was the year when it
was thought that HIV had been introduced into the United
States.
1
Within the past 2 to 3 years, the equivalent of a per-
manent MSM deferral has been reduced to include only
those who acknowledge MSM in the previous year.
1
The
policy has been widely characterized as discriminatory to
MSM, recognizing that the behavior and lifestyle of MSM,
just like that of heterosexuals, is heterogeneous. While the
reduction in the time limit is rational, it has not eliminated
the perception of discrimination among many MSM. We
will return to this issue later. While demonstrating forward
momentum, other limitations to a reduction in the MSM
time-based deferral, at least in the United States, include
that only a small number of prior MSM donors have pre-
sented to donate,
2
and as mentioned, MSM still represents
the highest risk group for HIV infection in the United States.
In 2016, 67% of diagnosed HIV infections in the United
States were attributable to MSM with the greatest increase
in risk in the 13- to 29-year-old age group, of which black/
African American MSM account for 49%.
3
In South Africa, where the overall prevalence and
incidence of HIV are much higher than in the United States,
the social impact of HIV/AIDS on transfusion medicine is
somewhat different in nature, but nevertheless instructive.
As outlined by Vermeulen et al.
4
in this issue of
TRANSFUSION, the major risk group for HIV infection is
the black majority population. It should be noted that only
in the recent past (1994) was white minority rule eliminated
in South Africa and replaced by an egalitarian, multiracial
social structure. Nevertheless, the South African National
Blood System (SANBS) continued to draw most of its dona-
tions from the minority white population and structured a
risk management system for donor safety on racial grounds,
effectively eschewing many donations from black African
donors. This practice was considered within the judicial sys-
tem and was declared discriminatory and unsustainable.
The blood system cured the situation by a number of mea-
sures, but most notably by welcoming all donors, enhancing
black African representation and implementing individual-
donation nucleic acid testing (ID-NAT). South Africa was
the first country globally to implement ID-NAT nationwide.
The bottom line of these changes was remarkable, as noted
by Vermeulen and coworkers.
4
Within the 10 years from
2005 to 2015, the proportion of donations from black Afri-
can donors increased from 6% to 30%, and among first-time
black African donors from 19% to 54%.
At the same time, the overall estimated residual risk of
HIV transmission decreased from 24 per million donations
to 13.4 per million, even though the black African donor
population had an HIV infection rate 30 times greater than
that of non-black donors. In other words, careful use of a
specific testing strategy permitted acceptance of a much-
higher-risk subset of donors, while improving the overall
safety of the system. ID-NAT interdicted 481 (1:16,100) sero-
negative donations considered to be in the infectious win-
dow period, 98% of which were subtype C (whereas subtype
B is the clade commonly identified in the United States).
5
Residual risks were estimated using incidence multiplied by
the window period, with incidence calculated using the
window-period/NAT-yield ratio model.
4
ID-NAT appears to be the most sensitive test system cur-
rently available, at least in the context of the seronegative
window period. Even so, Vermeulen et al.
4
noted that, over a
10-year period, representing 7.7 million donations tested
by ID-NAT, one HIV transmission from an RBC component
did occur (0.13/million), and more may have occurred
but were undetected (i.e., of the almost 3000 suspected HIV
transfusion-transmissions investigated, a definite cause could
not be determined for 63%). Even so, this was a 20-fold
reduction as compared with the period prior to ID-NAT
when two cases per year were observed. In an earlier study,
Vermeulen et al.
6
reported a single hepatitis B virus (HBV)
transmission from an RBC unit during the HBV seronegative
window period (0.34/million) versus an estimated residual
risk in the seronegative window period of 25 per million
donations. These breakthrough infections can be compared
doi:10.1111/trf.15081
© 2019 AABB
TRANSFUSION 2019;59;9–11
Volume 59, January 2019 TRANSFUSION 9