A year ago there was virtually no evidence on the
acceptability and feasibility of HIV self-testing in female sex workers, but a
series of presentations from Zimbabwe, Zambia, Uganda and Kenya at the 9th
International AIDS Society Conference on HIV Science (IAS 2017) in Paris, France, this
week suggest that self-testing has potential in improving the uptake of testing
among sex workers in Africa.
In follow-up questionnaires, 100% said the test was easy to use, 100% trusted the result they had been given and 98% were comfortable learning the result without someone else present.
Self-testing might have advantages for sex workers of privacy
and flexibility, allowing women to test themselves at a time of their choosing,
without needing to fit in with the hours of clinical services, or to interact
with healthcare workers who may have stigmatising attitudes. Its convenience
may also make regular, repeat testing more feasible.
Policy makers have great interest in self-testing because
they hope it may be a more acceptable option for groups of people who have
limited engagement with existing HIV testing services. The proportion of people
living with HIV who remain undiagnosed is particularly high in some groups and
sub-populations, including female sex workers.
Sue
Mavedzenge of RTI International reported on work she has done in Zimbabwe.
Female sex workers are disproportionately affected by HIV (prevalence over 50%,
compared to 14% in the general population), but their engagement with health
services does not reflect their heightened risk. Of all sex workers living with
HIV, only 64% are aware of their status, 43% are taking HIV treatment, and 34%
are virally suppressed. Increasing HIV testing is the necessary first step to
better engagement with both prevention and treatment services.
When self-testing was given as an option to around 600 women
seeking HIV testing in a dedicated sex worker clinic, 54% chose the
self-testing option. Self-testing doesn’t need to take place at home, and in
fact 96% of those using the self-testing kit did so in a private room at the
clinic. This gives the possibility of seeking staff assistance in case of difficulty
or of dealing with a reactive result – which 30% of those testing did have.
In follow-up questionnaires, 100% said the test was easy to
use, 100% trusted the result they had been given and 98% were comfortable
learning the result without someone else present. Substantial proportions
expressed a willingness to pay for testing kits (for example, 36% said they
would be willing to pay under USD$1 and 27% would be willing to pay between
USD$2 and USD$3).
Of those testing positive, 99% had connected with follow-up
services within two weeks of the test.
What’s the best way to distribute self-test kits to sex
workers? Among the Zimbabwean respondents, there were preferences for
distribution through clinics (62%), pharmacies (18%), peer networks (14%) and
workplaces (13%). However this was a sample of sex workers recruited through
clinics and there was also recognition that not all sex workers are engaged
with clinics.
Distribution models in Uganda and Zambia
Two randomised controlled trials, conducted in Uganda and
Zambia, explored distribution methods in more detail. While the studies were
done separately they had virtually identical methods.
Study staff recruited peer educators, who were current or
former female sex workers working in sex worker organisations. The peer
educators then recruited up to eight study participants each; to be eligible,
participants had to have exchanged sex for money or goods in the past month and
not be diagnosed with HIV.
Once a group of participants had been recruited they were
randomised, as a group, to one of three study arms:
- Direct distribution – the peer educator provides a
self-testing kit to participants, both at the beginning of the study and three
months later.
- Coupon – the peer educator provides a coupon which participants
can take to a drug store or health clinic and exchange for a self-testing kit,
both at the beginning of the study and three months later.
- Standard of care – the peer educator provides information
about existing HIV testing services.
In each country, just under 1000 female sex workers were
recruited as study participants. While women who had tested for HIV in the past
three months were excluded, testing rates were relatively high before the
intervention was provided – in each country, around two-thirds had tested
within the past year. It is possible that the researchers could have
demonstrated a greater impact of self-testing if they had recruited women with
less familiarity with HIV testing.
When the studies completed after four months, testing rates
were very high in all study arms. In Uganda, 100% of women in the direct distribution
arm had taken a test in the previous four months, compared to 97% of women in
the coupon arm and 87% of those in the standard of care arm. In Zambia, the
comparable figures were 95, 84 and 89% respectively. While the differences in
Uganda were statistically significant, they were not in Zambia.
Based on the Ugandan data, Katrina Ortblad concluded that
either model of self-testing achieved higher uptake than the standard of care,
but that direct distribution by peer educators performed better than the coupon
system.
However, in both studies, linkage to care appeared to be a
little poorer in the self-testing arms, although these differences were not
statistically significant.
Although intimate partner violence (IPV) is common in both
these study populations, there were only five cases of IPV that were linked to
self-testing recorded in the two studies.
Text message promotion to female sex workers and to truckers
A randomised controlled trial in Kenya tested the impact of
a very simple text message intervention on the uptake of self-testing by female
sex workers – and by truck drivers, many of whom may be their clients.
The setting was the North Star Alliance network of healthcare
clinics on major transport routes in Kenya. Using the clinics’ database of
electronic patient records, the researchers sent text messages (in English and
Kiswahili) to people who had not recently tested and were either female sex
workers or male truckers. In the intervention arm, the message informed clients
about the availability of self-testing at North Star Alliance clinics. In the standard
of care arm, the message simply encouraged clients to test for HIV.
Among sex workers, 6.1% in the control group and 15.9% in
the intervention group took an HIV test in the two months after text messages
were sent. This represents a statistically significant three-fold increased
odds of taking a test.
While the male truckers were much less likely to test, the
intervention also increased their odds of taking a test three-fold. Among
truckers, 1.3% in the control group and 4.1% in the intervention group took an
HIV test.
The right test?
Each of these studies employed the OraQuick HIV Self-Test, an oral-fluid based assay which this week
became the first self-testing device to be prequalified by the World Health
Organization. However, during questions and answers, Barry Kosloff of the
London School of Hygiene and Tropical Medicine asked whether this is the ideal
testing device to promote to individuals at high risk of having a recently
acquired HIV infection – such as female sex workers.
The window period of OraQuick
is relatively long, meaning that recent infections could be missed. The
development and licensing of self-test kits that are more sensitive to recent
HIV infection may be necessary if self-testing is truly to meet sex workers’
needs.