No-one with an undetectable viral load transmits HIV in two years of study
A study to look at whether people with HIV become non-infectious if they are on antiretroviral therapy (ART) has found no cases where someone with a viral load under 200 copies/ml transmitted HIV, either by anal or vaginal sex.
The PARTNER study included 1110 couples, 37% of them male gay couples, where one partner has HIV and the other does not. So far, in the first two years of the study, there have been no transmissions within couples from a partner with an undetectable viral load, in what was estimated as 16,400 occasions of sex in the gay couples and 28,000 in the heterosexual couples.
During the follow-up period, all the heterosexual HIV-negative partners reported condomless vaginal sex, 72% with ejaculation; 70% of the gay HIV-negative partners reported receptive anal sex, 40% with ejaculation. In comparison 96% of HIV-positive partners in the HPTN 052 study reported consistent condom use.
In total, 767 couples (282 gay) were included in this two-year interim analysis and there were a total of 894 couple-years of follow-up.
This represents an average follow-up of 14 months for each couple, although average follow-up for heterosexual men and women was longer than for gay male couples. The interim analysis estimated that the true risk of transmission lies somewhere between zero and 1% a year for anal sex generally. In the case of anal sex with ejaculation where the HIV-negative partner was receptive the risk is estimated to lie between zero and 4% per year; as follow-up continues, our estimate of the true likelihood may edge nearer to zero.
The researchers report that if the HIV-positive partners had not been on treatment in this group, a median of 86 transmissions would have been expected in the gay couples, and 15 transmissions in heterosexual couples.
Although some of the HIV-negative partners in the study became HIV positive, genetic testing of the HIV revealed that in all cases the virus came from someone other than the main partner.
Comment: PARTNER is still recruiting gay male couples and its full results will not be out until 2017. Till then we need to be cautious about what it has proved, and, as principal investigator Jens Lundgren pointed out, it will probably never be possible to establish with mathematical certainty the risk, if any, of transmission from someone with an undetectable viral load.
STIs greatly increase risk of acquiring HIV in pregnancy
In the two-year study of pregnant women and new mothers, all of whom had previously tested HIV negative during antenatal care, more than half of all HIV infections diagnosed were acute infections detected during pregnancy - reinforcing the need for repeat HIV testing during pregnancy and underscoring the need to use more sensitive methods that can detect viral RNA, especially in regions with high HIV prevalence and incidence.
The women had a median age of 22, 78% were married, and 7% reported a history of sexually transmitted infections (STIs). Women with a history of STIs had 3.8 times the risk of HIV infection and syphilis increased the risk tenfold.
While much remains to be done – an estimated 35% of pregnant women in low- and middle-income countries get an HIV test – improved access to services to prevent mother-to-child transmission of HIV has resulted in significant declines in transmission rates in some African countries. Botswana and South Africa have reduced transmission rates to below 5%; without any intervention, transmission rates would range between 25 and 40%.
Comment: A good example of how a study in a resource-poor setting also has implications for other regions. This study reminds us that pregnant women continue having sex, often with partners who assume they don’t have HIV; and it underscores how important STIs are in amplifying HIV infection risks in both women and men and in creating rapid chains of transmission.
Very different levels of PrEP uptake and adherence in three US cities
One of the first studies of open-label pre-exposure prophylaxis (PrEP) for at-risk gay men in three US cities (San Francisco, Miami and Washington DC) shows that the amount of interest shown by those offered or seeking it differed substantially. It also found substantial differences in adherence between the cities.
In total, 1059 HIV-negative gay/bisexual men and transgender women were offered tenofovir/FTC (Truvada) PrEP as part of the study.
Sixty per cent of those eligible eventually started taking PrEP. A surprisingly small 8% were African-American, and 42% had no health insurance. Sixty-nine per cent of those offered PrEP had previously heard of it – a big increase from 2011, when surveys in New York and Denver showed that only 22% of gay men were aware of PrEP.
Drug-level testing detected tenofovir in samples from 98% of volunteers, but the results indicated very different adherence patterns between the three cities. In San Francisco, over half of the trial volunteers had tenofovir levels consistent with daily dosing. In Washington DC, however, the figure was just over a third and in Miami only one in seven. However, another 43% in both Miami and Washington, and 40% in San Francisco, had levels consistent with taking around four doses a week. This dose, while not recommended, has been calculated by researchers as being over 90% effective.
This meant 42.5% from Miami, 20% from Washington and 8% from San Francisco were not taking enough PrEP to significantly reduce their risk of HIV.
Comment: In San Francisco, more men assessed for PrEP were eligible according to risk criteria, but fewer chose to take it up compared with Miami, where a group that was on average younger were less likely to pass risk criteria but more likely to be interested in PrEP if offered it. Interestingly, this reflects the findings of a London study from 2012. The 57% level of reasonable adherence in the Miami study is disappointing too, but perhaps a good indicator of what may be achievable in the ‘real world’ with younger, HIV-negative gay men not used to taking antiretroviral or other medication.
Not having sex with serodiscordant partners is HIV prevention strategy for 40% of gay men
A US study has found that only having sex with men of the same HIV status (‘strict serosorting’) was by far the most common method of trying to avoid HIV transmission in gay men who did not always use condoms.
This study found that 'condom serosorting' – being open to sex with men of a different HIV status (‘serodiscordant’ partners), but always using condoms with them – was far less popular as a strategy, as was ‘seropositioning’ – being top (insertive) if you are HIV negative, bottom (receptive) if you are HIV positive.
The study was designed to find out whether the sexual risk behaviour patterns men disclosed in a typical behaviour survey were part of a considered HIV risk strategy. Researchers at an HIV/STI clinic in Seattle asked gay male service users to fill in questionnaires detailing their actual recent sexual risk behaviour (condom use, status of partners, sex role and so on) and what sexual risk strategies they tried to use. The questionnaires were filled out by 964 men, 87% HIV negative and 13% HIV positive.
Fifty-five per cent of the men (both HIV positive and negative) reported that their choice of partner or behaviour was correlated in some way with their partner’s HIV status, and 86% of men agreed this was part of a conscious strategy. The remainder used strategies like monogamy, 100% condom use, or not having anal sex.
For 42% of HIV-negative and 32% of HIV-positive men, their main strategy for keeping themselves safe was to only have sex with people they knew or presumed to be of the same HIV status, or avoid sex with people who they knew to be of the opposite HIV status.
Comment: There has been a lot of concern expressed in HIV prevention circles recently that serosorting among gay men may be counterproductive in terms of reducing an individual’s risk of exposure to HIV, since the proportion of HIV infections transmitted by men who are undiagnosed and may think they are negative is rising. There is some evidence that serosorting may reduce HIV risk to some extent compared with no strategy at all but it is clearly inferior to using condoms, and also, as the PARTNER study (above) shows, involves rejecting some partners who may pose little or no danger of HIV.
One-in-ten HIV-positive gay men report using viral load to decide on condom use
The Seattle study above did not report on ‘viral sorting’ – people living with HIV only having sex without condoms if they have an undetectable viral load. A study from Germany, however, found that 10% of men with HIV regarded themselves as non-infectious if they had an undetectable viral load, and based their choices about sex consciously on this belief.
The researchers found considerable differences in condom use, STI risk and disclosure between men who adopted a 'viral sorting' strategy and other men with HIV. They found that 57.5% of men who used this strategy had had recent condomless sex – compared with 36% of those who did not – and that they were much more likely to have had anonymous casual sex (70% versus 44%).
The researchers were concerned that the adoption of a viral sorting strategy seemed to involve discussing and disclosing HIV status much less. Only 19% of men who adopted this strategy said they had recently disclosed their HIV status versus 42% of others, and only 22% said they had discussed the topic of HIV at all, versus 44% of others.
Comment: When the ‘Swiss statement’ was published in 2008, it was assumed that viral load would be discussed as part of HIV status disclosure between partners, rather than being used as a substitute for discussion. This study reveals that, instead, some HIV-positive men are using ‘viral sorting’ as a reason not to disclose. Given, however, what the Seattle study reveals – that HIV-positive men may meet with rejection by 40% of HIV-negative prospective partners if they do disclose – it is perhaps understandable if some HIV-positive men adopt this strategy.
More HIV testing and treatment on diagnosis needed to curtail UK gay epidemic
Increasing the proportion of HIV-positive gay men in the UK who have an undetectable viral load from the current figure of around 60% to 90% could result in a substantial drop in new HIV infections, a modelling study suggests.
A substantial increase in HIV testing rates would be required in order to achieve this. In addition, any decreases in retention in care, treatment adherence or condom use would have a negative impact on these predictions.
While approximately 20% of gay men living with HIV in the UK are unaware they have HIV, over 80% of those diagnosed are taking HIV treatment and 95% of those on treatment have an undetectable viral load. In all, approximately 60% of gay men living with HIV are virally suppressed. Yet around half a per cent of UK gay men continue to acquire HIV each year, and this figure may be increasing, due at least partly to an increase in the number of men having sex without using condoms.
At present, approximately 40% of men are diagnosed within a year of acquiring their infection, but the study modelled the impact of increasing this figure, and also of immediate treatment for anyone diagnosed with HIV. Increasing the proportion of men diagnosed within one year of infection to 60% could reduce annual incidence by 32% and if they all started treatment immediately annual incidence would be reduced by 64%..
Although many more people would be taking HIV treatment in the first few years, the numbers on treatment would be falling by 2030 as fewer men acquired HIV. However, this model is very sensitive to changes in condom use. In the scenario of increased testing and treatment cited above, a 10% fall in condom use would result in a few hundred extra infections each year, but if diagnosis rates are not improved, a 10% fall in condom use could more than double incidence.
Comment: A number of other scenarios are explored in the study – see the full report for more details. The unanswered question, of course, is how to increase diagnosis rates to 60% of gay men diagnosed within a year. The proportion of late-diagnosed gay men has been falling consistently but very slowly (0.5% decrease a year) in the last decade, but not the absolute number.
NAM/AVAC webinar: the prevention needs of people who use drugs in Europe
As part of its European HIV prevention work, NAM is collaborating with AVAC to provide a series of webinars (conference calls with accompanying slides) to train and inform prevention advocates and anyone interested in the newest developments in HIV prevention technology.
The next webinar is scheduled for 1700 UK time (1800 Central European Time) on Tuesday 22 April.
The session will cover harm reduction, pre-exposure prophylaxis and hepatitis C prevention in people who use drugs, with news from studies and about new initiatives in Europe.
To register for the webinar and get phone numbers and joining instructions click this link: https://cc.readytalk.com/r/4akxejmjjq32&eom
Speakers will Include Elliot Ross Albers from the International Network of People who Use Drugs (INPUD) and Shona Schonning from the European AIDS Treatment Group.
The webinar will be conducted in English and chaired by Rebekah Webb of AVAC.
Other recent news headlines
Two studies in monkeys of an injectable formulation of the integrase inhibitor drug GSK744LA have strengthened the evidence that it may work as pre-exposure prophylaxis (PrEP) in humans, and the first human study to gauge efficacy is now planned. The idea of a quarterly PrEP injection has interesting potential. Firstly, however, GSK744LA will have to pass stringent safety tests because once injected it cannot be removed; and secondly, how it is priced will be crucial to its usefulness as a prevention measure. The same drug is also being investigated as part of an injectable treatment for HIV, and this research may help answer some of these questions.
A study from the South African township that hosted the first-ever randomised controlled trial of male circumcision for HIV prevention has found evidence that women who are partners of circumcised men are less likely to have HIV themselves. HIV prevalence was only 15% lower in women who only had circumcised partners, but this was statistically significant. The study also found no evidence that circumcised men were less likely to use condoms.
HIV incidence in young black gay men in Atlanta, Georgia in the US is running at 12.1% a year – one of the highest figures for HIV incidence ever recorded in a population in the resource-rich world. This level of incidence means that a young black gay man becoming sexually active at the age of 18 has a 60% chance of acquiring HIV by the age of 30. The study that uncovered these figures established that lack of health insurance and solely having sexual partners from the black community were almost sufficient as factors, when combined, to explain why incidence in young black men who have sex with men is so much higher than in other men who have sex with men.
A community-based self-testing programme was used by three-quarters of the local adult population in urban Malawi, a study has found. The Malawian study is the first large evaluation of the acceptability and utility of self-testing in a resource-limited setting. A total of 13,966 test kits were distributed, of which 89% were returned, used. Uptake was calculated at 76% of the population. Over 40% of people were testing for the first time.
An extremely rare case of female-to-female sexual transmission of HIV has been reported in the United States. The report concerns a 46-year-old woman who appears to have acquired HIV during a six-month monogamous HIV serodiscordant sexual relationship with a 43-year-old woman. The newly diagnosed woman had no other risk factors for HIV and phylogenetic analysis revealed that the viruses the two women have are closely related.
Editors' picks from other sources
Heavy long-term use of inhaled nitrites (poppers) has been linked to new cardiovascular disease and cancer in HIV-positive and -negative gay and bisexual men in the US Multicenter AIDS Cohort Study (MACS). Among non-smokers, annual cardiovascular disease incidence approached 0.6% in HIV-negative and -positive gay men alike, compared with 0.2% and 0.4% respectively in HIV-negative and -positive men who did not use poppers. Among HIV-negative men, cancer incidence approached 600 per 100,000 person-years in heavy users, compared with about 400 per 100,000 person-years in non-users and occasional users.
from Eurekalert Medicine & Health
Although community network studies show that sexual relationships occur between members of "risk groups" – men who have sex with men, people who inject drugs and heterosexuals, little research has been done to help explain how HIV epidemics and programmes in one population affect others and how to reduce the risks of transmission. A recent US study shows that programmes for people who use drugs – like syringe exchange, HIV counselling and testing, and drug abuse treatment – have been associated with subsequent lower rates of AIDS incidence and death among heterosexuals.
The Greek government is “in denial” about the scale of the problems created by unprecedented cuts in health spending in the southern EU country, experts have said. The humanitarian group Doctors of the World has previously revealed that while in the past most of the patients who receive free treatment at the group's clinics have been migrants, over the past year almost half of the patients have been Greek citizens, due to the financial crisis. The experts claim that there is evidence of rising infant mortality rates, soaring levels of HIV infection among drug users, the return of malaria, as well as a surge in suicides from 2009 to 2011.