Sustained reductions in sexual risk behaviour following couples’ HIV testing

A programme of couples’ HIV testing and counselling in Zambia appears to result in durable reductions in sex without a condom in couples where one person has HIV and the other does not, according to an article published online ahead of print in Sexually Transmitted Infections.

Far fewer couples reported condomless sex in the months immediately following one partner’s diagnosis with HIV than before. Levels of condomless sex remained stable during up to five years of follow-up, as did biological indicators of condomless sex such as pregnancy and HIV seroconversion.

“Couples' voluntary HIV counselling and testing should be scaled up per WHO [World Health Organization] guidelines,” conclude Kristin Wall and colleagues from the Rwanda Zambia Research Group at Emory University.

Couples’ testing and counselling

Around half of couples affected by HIV in sub-Saharan Africa are ‘serodiscordant’, in which one person has HIV and the other does not. Moreover, most new infections originate from the HIV-positive main partner rather than from outside partners.

WHO guidelines recommend that couples and partners should be offered voluntary HIV testing services, with counsellors providing support to facilitate mutual disclosure of HIV status. In particular, it should be offered when one of the partners is known to have HIV. Antenatal settings are identified as particularly appropriate locations for testing couples and partners.

WHO defines couples’ HIV testing and counselling as being when two or more partners are counselled, tested and receive their results together. When couples’ testing shows that one partner has HIV and the other does not, the counsellor should emphasise the importance of preventing transmission within the couple. WHO recommends discussion of the preventive benefits of both condoms and antiretroviral therapy.  

A counselling curriculum, created with the input of the Rwanda Zambia Research Group, for the Centers for Disease Control and Prevention, provides guidance on how counsellors can help couples understand and accept that their HIV statuses are different, while diffusing difficult discussions about infidelity.

Counsellors should encourage mutual support, provide advice on the benefits of antiretroviral therapy, provide family planning advice, discuss the importance of testing the couple’s children if necessary, advise the couples on condom use, recommend avoiding outside partners, and link the couple with follow-up services.

Sexual behaviour following couples’ testing

Data come from the long-standing couples’ HIV counselling and testing programme in Zambia, collected between 1994 and 2012. Over 3000 heterosexual couples were followed up for an average of a year and a half following couples testing, with a fifth of couples providing three years or more of follow-up.

In 1656 couples the female had HIV and her male partner was HIV negative. In 1393 couples the male had HIV and his female partner did not.

Questionnaires collected data on participants’ self-reports of sex without a condom with their main partner, with data collected every three months. Relying on self-report would underestimate condomless sex, so the researchers also used biological markers – the presence of sperm on a vaginal swab, pregnancy and linked HIV infections. 

Reductions in sex without a condom following couples testing were significant and sustained over time.

In couples in which the man had HIV, there had been an average of 16.6 occasions of sex without a condom in the three months before couples testing. This dropped to 5.3 in the three months after testing, then 2.0 in the time periods after that.

Similarly, in couples in which the woman had HIV, there had been 22.4 occasions before couples testing, 5.2 in the three months afterwards, and 3.1 in the following time periods.

Turning to the biological markers, these data were only collected after couples’ testing, so a comparison with the time before testing cannot be made. But markers indicating sex without a condom did not increase or decrease in the subsequent time periods. The one exception is HIV infection in the HIV-negative partner, which was higher in the three months following testing than later on. This reflects infections acquired before couples testing but which did not initially show up because of tests’ window periods.

Although the majority of couples were followed up for just a year or two, in those couples who provided data for up to five years, there was no evidence of a relapse over time.

Data was also collected on self-reported sex with outside partners. Immediately following couples testing, men with HIV reported half as much sex with outside partners than before, and the figures did not rise again during follow-up. Few women reported sex outside partners, but there was a significant downward trend during follow-up.

“Our findings indicate that in HIV-serodiscordant heterosexual couples, reductions in unprotected sex and outside sex after CVCT [couples' voluntary HIV counselling and testing] are significant and sustained,” the authors say.

Additional findings

The study also provides clear evidence that researchers cannot rely on self-report to accurately measure sexual behaviour. For example, in couples in which the female partner had HIV, 29% of pregnancies, 39% of linked HIV seroconversions and 42% of sperm on swabs, occurred when the couples told researchers that they had always used condoms or had not had sex.

Another finding is that during almost all time periods, over 30% of couples were having condomless sex. The researchers comment that more risk reduction counselling appears to be needed.

Moreover, it can be targeted to particular couples – the study has identified the characteristics of couples more likely to have sex without a condom following couples’ testing. They are couples in which an HIV-negative woman is using injectable or oral contraceptives, drinks alcohol, or reports sex with outside partners, as well as couples in which the female partner (of either HIV status) is pregnant.