HIV self-testing (or ‘home testing’) is likely to have an
important place in future global HIV strategies, but at the moment there are
significant gaps in the evidence base of how it may best be made available, to
which populations and with what kind of support. So while the World Health Organization
(WHO) has clearly signalled its enthusiasm for the approach, its
new guidance on HIV testing reviews what we know so far about self-testing but does not
actually recommend it.
The guidance was launched at the 8th International AIDS Society Conference on HIV Pathogenesis, Treatment
and Prevention (IAS 2015) in Vancouver, Canada, last week, where several self-testing studies were also
presented.
WHO defines HIV self-testing as “a process in which an
individual who wants to know his or her HIV status collects a specimen, performs
a test and interprets the result by him or herself, often in private”. It
states that HIV self-test results can be accurate, so long as appropriately
regulated test kits are used and the manufacturer’s instructions are carefully
followed. But a self-test cannot itself provide an HIV diagnosis, which would
require a confirmatory test at a health facility.
WHO believes that by giving people the opportunity to test
discreetly and conveniently, HIV self-testing may increase the uptake of HIV
testing among people not reached by other HIV testing services, including many who have never taken a test. It describes several possibilities for ways in which
self-test kits could be delivered or distributed:
- Open-access:
over-the-counter in pharmacies or groceries, ordered from websites, or
distributed from vending machines.
- Semi-restricted
distribution by community health workers.
- More
restrictive distribution by health workers in clinical settings.
Taking the second or third approach, an additional option is
for a health worker to be present or available while the person takes the test.
They could offer support and linkage to care if needed. However, their presence
could undermine the attractiveness of self-testing for people who have concerns
about confidentiality, while clinic distribution is unlikely to reach people
reluctant to attend health facilities.
The uncertainty about the pros and cons of the different
approaches with different groups of people means that the World Health
Organization is not making recommendations for the moment. But “WHO is working
with collaborators to generate the evidence needed to issue recommendations and
additional guidance on this topic.”
An important evidence gap relates to implementation in
resource-limited settings with men who have sex with men, sex workers, people who inject drugs and other key populations. In places where pervasive
social stigma and concerns about confidentiality make health services difficult
to access, self-testing may have particular advantages for these groups in
terms of privacy and autonomy.
But Peter MacPherson of the Liverpool School of Tropical
Medicine said he was aware of 20 self-testing studies among the general
population in African countries, but only of six among key populations. There
are also few data on adolescents and older men, although HIV testing has low
uptake in all these groups.
Harsha Thirumurthy of the University of North Carolina described
a project which provided Kenyan women with self-testing kits for themselves and
encouraged them to distribute extra kits to people they knew. At antenatal and
postpartum clinics, women were given two extra kits, which they mostly passed
on to primary partners and to female friends. Sex workers attending a drop-in
centre were given four extra kits, which they mostly distributed to clients and
to primary partners.
The project succeeded in helping couples to test and brought
testing to men, who are generally hard to reach. Moreover, the proportion of
HIV-positive results was high: 5% in tests distributed by pregnant women and
15% in tests passed on by sex workers.
While self-tests may be used alone and in private, some
people choose to test in the presence of a friend or their partner.
Three-quarters of the test kits distributed by the Kenyan women were used while
they were in the room, with many couples testing together. This hadn’t been
suggested by the researchers.
Similarly, one quarter of transgender women offered
self-testing kits in San Francisco tested with someone else present. Sheri
Lippman of the University of California said that the qualitative data from
this project found that participants made difficult trade-offs between privacy
and support. There were concerns about confidentiality and stigma when
attending clinical settings, but social and emotional support remained
important, hence the value of having a close friend present when testing.
This was the first ever study of self-testing in transgender
women. In this highly marginalised population (many were homeless and sold sex),
almost all participants said that the tests were easy to use. Two-thirds would
prefer to use a self-test for their next HIV test but a price ticket above US$20 would be prohibitive.
The one key population for which there is a body of evidence
on self-testing is American gay men. David Katz of the University of Washington
added to this, outlining a study which randomised half a group of 230 gay men to have
self-testing kits available through the mail and the other half to just have
access to existing testing services. Those with access to self-testing tested
for HIV more frequently, with 76% testing at least every three months (as the
researchers had recommended), compared to 54% of those in the control group.
There were no differences in sexual behaviour.