CATIE News

28 November 2019 

CDC study finds that HIV self-test kits increase testing frequency and uncover infections

  • Access to self-test kits increased HIV testing rates among men who have sex with men
  • More cases of HIV were diagnosed among study participants offered self-testing
  • Participants who used self-testing were just as likely to be linked to care upon diagnosis

Although Canada and other high-income countries are making progress against the HIV epidemic, gaps in the continuum of testing, care and treatment remain. For instance, the Public Health Agency of Canada estimates that 14% of people with HIV are not aware of their infection.

Making opportunities for HIV testing more convenient and widespread could help reduce the proportion of undiagnosed people with this virus. One possible way to increase HIV testing is by making self-test kits for use at home available.

To explore this idea, scientists at the U.S. Centers for Disease Control and Prevention (CDC) conducted a clinical trial with about 2,600 gay, bisexual and other men who have sex with men (MSM), all of whom disclosed that their previous HIV test result was negative. All participants had access to online HIV testing resources that identified local places where HIV testing could be done. They also had access to telephone counselling should they find it necessary. Scientists randomly assigned participants to one of two groups: access to self-test kits or no self-test kits (this latter group acted as a control, or comparison, group). The study lasted for one year.

Over the course of the study, scientists found the following trends among participants who received the self-test kits:

  • higher rates of HIV testing
  • more cases of HIV infection were uncovered

Participants who received the self-test kits were encouraged by the scientists to give some of them to friends and family. These kits helped to uncover HIV infections among participants’ social networks.

The CDC scientists concluded that “the distribution of HIV self-test kits provides a worthwhile mechanism to increase awareness of HIV infection and prevent transmission among MSM.”

Study details

The CDC scientists called their study eSTAMP. To recruit volunteers, those on the study team stated that they placed advertisements on “social network, music and dating sites frequented by MSM.”

All participants completed a survey upon study entry and were then randomly assigned to either receive self-test kits or to not receive them.

Focus on the group that received self-test kits

Participants who received the self-test kits were mailed the following:

  • “2 oral fluid self-tests” – the OraQuick in-home HIV test, made by OraSure Technologies
  • “2 fingerstick whole blood HIV self-tests” – the Sure Check HIV 1/2 Assay, made by Chembio Diagnostics Systems

Once participants had completed quarterly surveys, they could receive additional testing kits.

Participants received links to online videos with instructions on how to use the kits. They had several ways to report their test kit results: through the study website, in quarterly surveys or on the telephone.

Most participants were recruited from dating (57%) and music (40%) websites and were younger than 30 years of age; all were adults. The distribution of major ethno-racial groups was as follows: white – 58%; Hispanic – 23%; black – 10%. All participants disclosed that they had engaged in anal intercourse with other men in the past year.

Results

According to the scientists, participants who received the self-test kits “reported testing more frequently” – on average, five tests versus two tests.

Most participants (77%) in the self-test group “reported testing 3 times or more before their 12-month survey, compared with 22% of the participants in the control group.”

When the scientists compared testing behaviour prior to and during the study, they found that there was “a 56% increase in annual HIV testing among self-test kit participants.” Among people in the control group, the scientists found only a 7% increase in annual testing.

Focus on HIV infections over time

There were 36 cases of HIV infection identified during the study. Here are some findings about those cases:

  • During the first three months of the study more HIV infections were reported by participants in the self-test group – 12 infections versus two infections in the control group.
  • During the entire 12 months of the study, twice as many HIV infections were identified in the self-test group – 25 infections versus 11 infections in the control group. According to the scientists, “nearly half of these infections were among participants who had not been tested in the preceding year.”

Linking to care

Of the 36 people who became aware of their HIV infection during the study, 72% disclosed that they had been linked to care after their diagnosis. There was no difference between rates of linkage to care between participants who tested positive in either of the study groups.

HIV in social networks

According to the scientists, participants in the self-testing group “reported that 52 of their social network members obtained a positive test rest.” Of these 52 people, 29 were not aware of their HIV infection status prior to using the study’s self-test kits.

Key points from the study team

  • “The distribution of HIV self-tests to MSM recruited via the internet significantly increased the frequency of testing among self-test participants compared with control group participants and facilitated the distribution and use of HIV self-tests to social network members. The intervention identified more previously undiagnosed HIV infections than in the control [group] and identified infections among self-test participants’ social network members.”
  • “Distribution of HIV self-test kits had a substantial prevention benefit among social network members: during the trial, more new HIV infections were reported among social network members who used the study self-tests than among the self-test participants themselves.”
  • The scientists noted that mailing HIV self-test kits to participants allowed them to “reduce some of the barriers associated with clinical and peer-based HIV testing programs, such as patient and physician time, testing costs, stigma and face-to-face interactions. The recruitment strategy may also have resulted in reaching a higher-risk population based on the nature of sites from which participants were recruited.”
  • “These results also reinforce the importance of the [CDC HIV screening recommendations for MSM]: participants who had not tested in the past year accounted for nearly half of the newly identified infections in the study. Hence, this approach may be a useful strategy to reach MSM, especially those who are not testing at least annually and those who have never accessed existing HIV testing services.”
  • “Based on [the study’s findings], HIV prevention programs might consider adding an HIV self-testing mail distribution component to their portfolio of HIV prevention services for high-risk populations and providing high-risk MSM with additional kits to promote distribution to social network members.”

A note about the timing of HIV self-testing

The scientists made this important point: “The potential for HIV transmission exists if a false-negative result is obtained when the HIV self-test is used during acute HIV infection when [the amount of virus in the blood is very high], or if the test is performed incorrectly. Therefore, people who use HIV self-tests should be discouraged from using the self-test as a point-of-sex test.” That is, it is not a good idea to use HIV self-test kits prior to sex, as there is a possibility of a false-negative test result. Further explanations about HIV testing appear in the Resources section at the end of this article.

Bear in mind

As with all studies, the present study was imperfect. However, it is a very useful step forward and confirms previous research in the U.S. and Australia that found that many MSM would welcome opportunities to use HIV-self test kits.

Resources

Aussie study finds HIV home-based test kits welcomed by gay and bisexual menCATIE News

Reaching the first 90: how HIV self-testing can help us end the HIV epidemic – CATIE Blog

HIV Testing – I know my HIV status – CATIE

The HIV testing process – CATIE Fact sheet for service providers

HIV testing technologies – CATIE Fact sheet for service providers

—Sean R. Hosein

REFERENCE:

MacGowan RJ, Chavez PR, Borkowf CB, et al. Effect of Internet-distributed HIV self-tests on HIV diagnosis and behavioral outcomes in men who have sex with men: A randomized clinical trial. JAMA Internal Medicine. 2019; in press.