Risky business?

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Post by David Menadue11 Jun 2014

For some, the PARTNER study has blurred the lines between safe and unsafe sex but, as David Menadue reports, don’t throw away the condoms just yet.

Almost zero risk of HIV transmission between poz-neg couples— that’s the initial finding from the European-based PARTNER study. There are crucial caveats, however: the positive partner must be on antiretroviral therapy (ART) and record an undetectable viral load. Still, the results from the two-year study are welcome news for couples in a serodiscordant relationship.

Almost 40% of the 1,110 couples who took part in the PARTNER study were gay. In order to qualify, couples had to be engaging in unprotected sex; the HIV-negative partner could not be on post-exposure or preexposure prophylaxis; the positive partner must be on ART, and have a viral load less than 200 copies per ml. As a consequence, 343 couples were excluded from the analysis for not meeting the requirements. The 767 couples remaining reported 44,000 instances of condom-less sex, without a single seroconversion.

(While there was HIV transmission recorded in the cohort, DNA testing suggested some negative partners had sex outside of the relationship — presumably with someone unaware of their true HIV status, or who didn’t have an undetectable viral load .)

So — providing the positive partner is on ART and undetectable — can serodiscordant couples give
condoms the flick? PARTNER principal investigator Professor Jens Lundgren said, while the results are promising, a
transmission rate of 1% a year for couples engaging in unprotected anal sex could not be ruled out; where the negative partner reported receptive anal sex with ejaculation, the transmission risk rose to 4%. When asked how safe these odds might be, Professor Lundgren replied: “It’s up to people to decide what is safe in life.”

However, serodiscordant couples have been cautioned to wait for further research results as the risks of transmission for partners who continue to have condom-less sex is likely to increase over time. There is a possibility, for instance, that an HIV-positive person’s viral load may fluctuate — particularly if they are not in the habit of taking their treatment on a regular basis. Resistance to HIV medications can certainly develop in this scenario and people can be unaware that they are no longer undetectable, and potentially infectious.

As you would expect, the study’s findings have provoked much discussion in the HIV community. Positive Living asked a range of people for their views on what the early results from PARTNER might mean.

Professor Andrew Grulich is an epidemiologist from the Kirby Institute in Sydney and chief investigator for an Australian study looking at transmission rates, called Opposites Attract. Grulich thinks the PARTNER results are encouraging news but said people should be cautious about making definitive conclusions about the study’s findings, particularly when it comes to gay men and anal sex. “It is early days yet, and the PARTNER study has two more years to go. It is going to be important to see if there are any HIV transmissions in four years when they may make their final report.”

Grulich would also like to see a bigger sample size for the Australian research. Opposites Attract currently has 120 Australian serodiscordant gay male couples enrolled in the study. “We are hopeful we can increase this to around 200 couples with recruitment from Brazil and Thailand,” he said. “We hope other Australian couples will still join too. If [Opposites Attract] can add further to the PARTNER study’s research sample of gay men, we should be able to make a stronger statement in a few years time.”

Colin Batrouney, Manager of Health Promotion at the Victorian AIDS Council thinks the study is a very important finding. “Of course for a big reduction in HIV transmissions to happen in the community, individuals will need to know they are HIV positive, so there would have to be an increase in numbers testing for HIV. If testing positive, they would need to make a decision to go on treatment, which we know many are not prepared to do unless there is a compelling clinical reason to do so,” said Batrouney. “I see another obstacle as well for some people. People will have to have a frank discussion with their sex partners about the relative safety of having unprotected sex, and for disclosure of an undetectable viral load to happen upfront.”

Brent Allan, Executive Officer at Living Positive Victoria, said, if the PARTNER results stand up, disclosing your HIV status may become easier. “Disclosure is such a vexed issue for many positive people because they fear rejection and potential legal implications if they don’t,” he said. “This study could change the perceptions of positive people in the community as being someone to be avoided as a sex partner to someone who is active in ensuring they are lowering their transmission risk to others. In other words, they are ‘healthy and responsible sexual partners’. But education of the broader community will need to happen for this to occur.”

Journalist and blogger Gus Cairns recently wrote in The Huffington Post that the biggest message to take from the PARTNER study is that gay HIV-positive men need to get on treatment and get their viral loads down to undetectable. “It confirms that we gay men have to change our ideas about infectiousness and HIV radically if we are to stand a chance of reducing HIV infection in our community.”

Addressing HIV-negative gay men, and using UK statistics, Cairns said: “Of [the] HIV-positive people you may be dating, two-thirds will know they’re positive, but won’t be infectious. But of the infectious ones, two-thirds will think they’re negative.” (Australian figures echo those of the UK.)

Cairns added: “If you’re an HIV-negative guy and you don’t use condoms every time with a new date, then just date HIV-positive guys on treatment.”

Other interesting data observed in the PARTNER study was that, even though 16% of the gay male cohort experienced a sexually transmissible infection (STI), this did not lead to an HIV infection for the negative partner. This counters evidence that having an STI increases a person’s vulnerability to HIV transmisisons. The investigators warned though that it is premature to be certain about these findings and that more research is needed.

Even so, “This is very encouraging news,” said Dr Louise Owen, Director of Sexual Health Services Tasmania. “But I would advise caution in relying on these findings about STIs just yet. It is still early days for us to be sure there is no relationship between STIs and HIV transmission in the setting of undetectable viral load, and people with HIV need to keep
up their regular STI testing practices, regardless,” she said.

“My concern is for the sexual health of my HIV-positive patients. I don’t think it is good for their personal health to get an STI . For example, syphilis can progress to neurosyphilis in an HIV-positive person much quicker than for an HIV-negative person. And as we now know, hepatitis C can be sexually transmitted; the health consequences of contracting that can be significant for people living with HIV.”

Steve and Dan have been in a relationship for five years. “I knew Dan was positive when we met and of course we used condoms pretty much 100% of the time at first,” said Steve.

“After a while,” added Dan, “we asked for advice from our local HIV-positive group. They said they couldn’t say anything definite but [unprotected sex] was certainly not as risky if I had an undetectable viral load .I did have, so that got us wondering. “We also asked other people in poz-neg relationships, including some positive women we knew. They said they hadn’t been using condoms with their negative partners for over a year and no one had seroconverted.”

“The interesting thing they told us was it was safer to do this when the HIV-positive partner was not the male,” said Steve. “In gay male terms that meant that research showed it was safer to be a bottom if you were the HIV-positive partner. Sometimes now we don’t use condoms, but it’s only when I am the top.”

“I prefer being the bottom anyway,” said Dan. “But we might re-evaluate things once we know more about studies such as PARTNER.”

There could be further implications from PARTNER for HIV-positive people. “There can be no reasonable legal action you can take against people not using condoms,” said Professor Lundgren, “assuming people had maintained their undetectable viral load .”

Could it be possible, therefore, for an HIV-positive person to argue before a court in NSW, for instance, that by taking
treatments they have “taken reasonable efforts to avoid the transmission of HIV”? (The term “reasonable efforts” currently only refers to the use of condoms.) Will prosecutors be less inclined to start legal proceedings against a poz person under HIV exposure or reckless endangerment laws if it can be proven that the positive person is extremely unlikely to transmit the virus during unprotected sex?

Legally, these are questions of fact that would need to be tested before a jury. In the past, Australian courts have been reluctant to consider undetectable viral load to be an adequate safeguard in endangerment cases. But courts are guided by expert evidence in these matters and, as the scientific consensus shifts, the courts should — eventually — follow. At the very least, such evidence provides more strength to the case for HIV advocates to push further for the decriminalisation of HIV.

Professor Lundgren also believes PARTNER shows that, if a person has had unprotected sex with an HIV-positive person who is virally suppressed, there would be no need for post-exposure prophylaxis. “The odds of transmission in one sexual act would be deemed to be so low that taking a month’s prescription of antiretrovirals to prevent infection might not be justified,” said Lundgren.

From my point of view, the PARTNER study gives greater assurance to serodiscordant couples who are regularly weighing up the risks of transmission with any unprotected sex they have. For positive people with an undetectable viral load who have a lot of casual sex, I think it should give people more confidence to disclose their status before sex — and to use the opportunity to get their partners up to speed with the latest thinking in the science on HIV transmission.

Regardless of whether you think you are uninfectious though, you owe an HIV-negative person the right to decide not to have sex with you if they are worried about infection. Failing that, you can always revert to the old tried and tested method . . . and put on a condom.