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Articles tagged with: HIV prevention


Zeroing in on zero risk

Monday, 24 March 2014 Written by // Bob Leahy - Editor Categories // As Prevention , Current Affairs, Research, Health, International , Treatment, Living with HIV, Opinion Pieces, Bob Leahy

If you have an undetectable viral load, you're probably non-infectious say the just-released PARTNER Study results. But is there still a risk from sex without condoms and why are people still arguing about what is safe? Bob Leahy reports.

Zeroing in on zero risk

“When asked what the study tells us about the chance of someone with an undetectable viral load transmitting HIV, presenter Alison Rodger said: "Our best estimate is it's zero."

“The PARTNER study still recommends using condoms.” PARTNER study Q and A document.

Confusion. Elation. Anger. All were much in evidence following this month's release of the interim PARTNER study results from CROI 2014. "No-one with an undetectable viral load, gay or heterosexual, transmits HIV in first two years of PARTNER study” said the March 4 headlines. 

That was amazing news, exactly what many of us had hoped for. But reaction has been mixed.

Dazed and confused.

It’s true the message is a bit confusing. Why, for instance, would researchers recommend the use of condoms in what looks like a zero risk scenario? (One could also ask is it ever the place of researchers to recommend poz folks don rubber?  Aren’t we supposed to review the facts and make our own choices?)

Truth is what’s behind this is that the concept of zero risk is a bit hard to pin down, particularly in a sample this size (767 couples, 40% of them gay) and with a trial of this duration – two years to date, but ongoing. So researches build in to their risk calculations “confidence limits” which in this case are 95% but would increase over time. So it's mathematically possible to establish a worst case scenario which is described in thus: “PARTNER study principal investigator Dr Jens Lundgren pointed out that this meant that there was a maximum 5% chance that over a ten-year period, one in ten HIV-negative partners in a gay couple who had unprotected anal sex might acquire HIV; equally, though, it was more likely that their chance of acquiring HIV from their partner was nearer to zero, and indeed could be zero.”

So expect to hear a lot more of this 5% figure in the weeks and months to come as the prevention community, who have largely yet to speak on this issue but often take a conservative stance, will likely want to emphasize that zero risk has yet to be mathematically proven. And they are right.

We’d also point out that crossing the road is not zero risk.Travelling by air is not zero risk. Both can have dire consequences. But they are slim - so we do both. But our attitude to risk is individual, complicated and not easily or comfortably dictated by others.

“Jens Lundgren pointed out, it will probably never be possible to show with mathematical certainty that the risk of transmission from someone on successful HIV therapy is absolutely zero”

Hence the recommendation from PARTNER to use condoms. True, this make sense if you wish to avoid contracting STI’s, although whether STI’s represent a greater threat to those with an undetectable viral load than, say, to a negative individual is far from proven, although it is often implied. But do condoms make sense given what we now know is an extremely low (negligible) risk of HIV transmission? That is clearly a matter of individual judgement.

Even the medical profession seems confused. There are actually few pronouncements to date on what PARTNER means for HIV prevention but this one from HIV doctor Joel Gallant is typical. Gallant says “Seronegative MSM should understand that there is still a small possibility of becoming infected by a partner with an undetectable viral load. This could happen in one of two ways: (1) since we check the viral load every few months rather than every day, the viral load may have increased after the last test, or (2) there may be detectable virus in semen even though it’s undetectable in blood.  We know this blood/semen discordance occurs, especially in people who have not been on ART for very long. Seronegative men should still consider using condoms with a partner who has an undetectable viral load, especially for the highest risk activity: receptive anal sex with ejaculation.“ 

Dr. Gallant is theoretically right in that there could be a blip in viral load but clearly that was not evident in the PARTNER study or we would have seen infections here and epidemiological data elsewhere where virtually no recorded infections have occurred. Similarly the issue of virus in the semen, if occurring frequently - it doesn’t - and at levels sufficient to cause transmission - they don’t - would also have been reflected in PARTNER results and elsewhere, but it was not. In fact the virus in the semen issue, we’ve always maintained, is a red herring that we’ve done our best to dispel – but it lingers on like a bad smell, but thankfully getting weaker by the minute.

Hopefully the STI issue – the idea, not well proven though often repeated, that STI’s raise seminal viral load -  goes the way of the dodo with PARTNER, although expect to see it trotted out as justification for using condoms for some time to come.  But again, in PARTNER NO transmissions occurred despite quite high levels (16% occurrence rate) of STIs, especially in the gay couples. That seems to indicate that all that talk about STIS was a red herring too.

Anger in the streets

Strange as this may seem - because this is mighty good news isn’t it? -  there has been heated debate since release of the PARTNER study on how good this news really is. So vocal were the naysayers in fact that Mark S. King penned an angry postWill HIV Ever Be Safe Enough for You?” in response to what he sees as “willful ignorance coming from gay men (who are) threatened, frightened, and dismissive of science.” 

Mark goes on “To date, there is not a single confirmed report of someone with an undetectable viral load infecting someone else, in studies or in real life. Just don’t tell that to a sizable contingent of skeptical gay men, many of whom took to their keyboards to dismiss the PARTNER findings. Phrases like “false sense of security,” “positive guys lie,” “junk science,” and “if there’s even a small risk” appeared on Facebook postings and in web site comment sections.”

Web site comments? Look here for a sample of the thoughts of dozens of thoughtful people, poz and neg, who don’t believe PARTNER results change much of anything. Here's one to whet your appetite

"Obviously it is quite clear that you (and those who share your perspective) should really just go f&*k yourself. That’s safest for everyone."

Another sceptic is Dr. Adam Green, Associate Professor at the University of Toronto Department of Sociology. Raising first the 'virus in the semen' issue which doesn't really bear scrutiny he goes on to say “It's also true that science has a way of telling us "A" is true on Monday, but false on Friday.  Findings change, interpretations of data change, and in this context I think a lot of people are afraid to take this study or that study as "the gospel".   

No wonder then that Mark shot back “Regarding the study itself, we have more than one study that has delivered these results, the last being a couple of years ago. And I must strongly contend that two years, 800 couples and 30,000 documented sex acts later is good enough for me, thank you. If, in the remainder of the 8-year study they document an infection or two, it would still be so statistically remote that I'm not going to sweat it. Finding HIV in semen or hiding in cells, as evidenced by PARTNER, does not an infection make. Not a single one. I really don't know how much more clear this study could be in this regard.”

Green of course had ignored that the PARTNER study effectively confirms the findings of The Swiss Statement in 2008  and HPTN052 in 2011. 

Gus Cairns, who writes for said thus to Green  "We've known since HPTN052 in 2011 at least (in fact we knew well before, at least since the Swiss Statement in 2008) that the chances of anyone with an undetectable viral load infecting anyone were remote. This isn't a sudden and unexpected finding. We needed to have it clinched for anal sex. PARTNER has helped, though we still need our knowledge of risk narrowed down further - that's why they're continuing the study."

Elation - time for dancing in the streets?

Some (many) have hailed PARTNER as great news, the news we have been waiting for, the gay man’s HPTN 052. (HPTN 052, hailed by CATIE as a game-changer applied to heterosexual couples only so the inclusion in PARTNER of gay couples was indeed a major advancement in our knowledge.)

But what’s not to like in PARTNER? It means that those of us who are HIV+ but undetectable are likely not the least bit infectious. People need not be scared of us. It brings peace of mind to serodiscordant couples who don’t always use condoms. It potentially means reduction in the stigma surrounding HIV. It proves that treatment as prevention works and paves the way for global strategies to really get the epidemic under control. It makes the case for criminalization of non-disclosure where one is undetectable all that much thinner. Altogether, although full results of PARTNER are not in, it does look like 2014 will be a banner year in the history of the epidemic.

Says publisher John McCullagh “This is a very significant finding indeed, given that the participants were selected from among people who reported not using condoms consistently. It means that poz gay guys are unlikely to infect their negative partners. This is something that I’ve personally believed for some time, but having it confirmed through a scientific study is very liberating. It’s reassuring to know that I’m an unlikely vector of HIV transmission.

"Another important finding of the PARTNERS study, and this is new, is that it showed that poz people with an STI are not likely to transmit HIV (although, of course, they could still transmit the STI itself). This too is a departure from earlier studies which have always cautioned that the presence of an STI could increase the possibility of HIV transmission.

"This is all a big deal. It confirms that, for the most part, HIV transmission is not occurring via positive people on treatment with undetectable viral loads but rather via those who don’t know their status, or those who think they are negative but are actually positive, or those with detectable viral loads. This is significant information for prevention work. And one would hope that it would reduce the stigma towards those of us living with HIV. But we face challenges in both areas. One only has to read the dismissive comments that have appeared in the media - often, I regret, from my fellow gay men - since the PARTNERS study interim findings were released to know that community engagement and buy-in is going to be a challenging, uphill struggle.”

Mark S King said of what this all means for our community ”The PARTNER study threatens the view that positive men are nothing more than risks that must be managed. The study kills the HIV positive boogeyman. It means positive gay men who know their status might actually care enough about their health to seek out care, get on treatment, and become undetectable. And, once the positive partner is no longer a particular danger, both partners would bear responsibility for their actions. What an enormous psychic change that would require in our community."


Increasingly, risk decisions are informed by gay men themselves. True, many wait to hear what the prevention community offers them, but we have a tradition of informed voices outside the prevention community, using the same science-based approach as their professional counterparts to arrive at conclusions that are different but both correct and prescient. Recently, for instance, our own Marc-André LeBlanc anticipated PARTNER by producing the much read article Fuck Poz Guys based on the premise that sex with a poz partner with an undetectable viral load afforded a much higher degree of protection for neg guys than having sex with other neg guys. (The Ontario prevention community currently only admits to undetectable viral load affording “reduced risk”.)  Even earlier, back in January 2011 in Mark S. King’s article “Five Things About HIV (They’re Not Telling You)” POZ founder Sean Strub said “an undetectable viral load may rival a condom.” (Actually it’s become clear an undetectable viral load far exceeds the protection typically provided by condoms, whose efficacy under normal use, is in the 70-80% range, but that’s beside the point.) What has become clear is that poz guys in the know are often predictors of what eventually becomes established fact. The value of lived experience combined with a science-based approach, curiosity and a desire for the untarnished truth are not assets to be sneezed at.

So where do we go from here? Says John McCullagh ”Risk reduction counselling needs to be updated in light of these new findings on HIV transmission. While I’d like this to happen right away, I recognize it brings with it some challenges that will take time to resolve. How many gay men living with HIV, for example, actually have undetectable viral loads? In Canada we just don’t know, nor are there any estimates of how many have made it through the various steps of the HIV care and treatment cascade. However, the numbers from British Columbia are not encouraging. In that province, only 35% of all people living with HIV have made it through all those steps and achieved an undetectable status. While this figure includes all PLHIV in BC, one hopes that the percentage would be higher if just gay poz guys were included - as I think we’re probably more engaged in the cascade. But, again, we just don’t know. So this means that we will need to strategize carefully how the new information from the PARTNERS study will be shared and current programming modified in light of it. It also has implications for a stepped-up and more integrated approach to HIV testing, care, treatment and support programming so as to maximize effective outcomes.

"So thinking through how we develop and implement interventions based on the interim findings of the PARTNERS study is crucial. But the bottom line remains that gay men and others living with HIV, and those at risk for HIV, need the best information available to assist us in making informed decisions about our health.”

John is right, of course. The HIV prevention community, at least here in Ontario, has yet to speak. But we supect that whatever they tell us will be more nuanced than “The PARTNER study still recommends using condoms.”

In fact PARTNER did go further and said “the results from the PARTNER study and other studies will help inform people about the risk of transmission when not using a condom, so they can decide for themselves whether or not to use a condom.” Here, here.

Final note

PARTNER has resulted in some calling undetectable viral load “the new negative”. Said David Duran in POZ magazine “The more we open up and discuss what it means to be HIV positive with an undetectable viral load, the more society, especially those within our own community, will begin to understand, learn and accept. . . Be proud of having an undetectable viral load.”

Clearly, this is the beginning of a conversation, not the end.