… though we need a combination strategy.
On 6th March I attended the latest study day organised by the National HIV Nurses Association on ‘HIV prevention strategies: The role of the nurse’. The day couldn’t have happened at a more apt time. This is particularly because of the announcement of the interim results from the PARTNER study, which showed very low risk of transmission with an undetectable viral load in sero-different partners.
In addition to the conventional prevention strategies we all know about: testing, prevention of vertical transmission, and PEP (Post Exposure Prophylaxis), the study day included talks on other strategies I would never have thought of such as negotiated safety and partner notification.
Dr Valerie Delpeche from Public Health England set the scene for the day by looking at the current picture of HIV in the UK. By the end of 2012, there were approximately 98,400 people living with HIV. 21,900 people remain unaware of their HIV status. 47% of those newly diagnosed in 2012 had a CD4 count of less than 350. The undiagnosed remain the biggest challenge and it’s clear that this is where the main focus of prevention efforts ought to be. She also reminded us of how well the UK are doing in our treatment cascade in comparison to other countries. Our treatment cascade, indicates that, amongst others, 97% of people newly diagnosed are linked to care within 3 months. Of these, at least 95% are retained in care (though it’s important to remember that this means that out of the 76,840 diagnosed, 3850 are NOT retained in care). Of those in care, 89% receive ARVs, and 95% of these achieve a viral load of below 200. Given this therefore, the UK’s Treatment Cascade should probably be referred to as a Treatment Continuum!
Home testing and non-traditional settings
Dr Miriam Taegtmeyer from the University of Liverpool presented on Home testing in non traditional settings. This was an interesting presentation especially as home testing/self testing will become legal in the UK in April 2014, when over-the-counter oral fluid tests will become available from pharmacies. A number of provider-initiated self-testing kits with varying degrees of ease of use are already available. Dt Taegtmeyer said it is only a matter of time before these become available to the public.
The key take home messages were:
- A significant number of people in the UK remain unaware of their HIV infection.
- Patients should be offered HIV testing in a wide range of settings and Point Of Care Testing (Explain?) using rapid test methods can offer this.
- There are pros and cons for home-testing and it should be offered in a framework with clear pathways for confirmation, referral and linkage to care should someone have a positive result.
- Nurses play a direct role in conducting rapid tests and in supporting the emotional and other needs of those who test at home.
Treatment as prevention: the evidence base
Juliet Bennett, an Independent Nurse Specialist, then presented the evidence base for Treatment as Prevention (TasP). Juliet clarified the definition of Treatment as Prevention as:
- The use of ART specifically for its prevention benefits irrespective of the individual’s CD4 count.
- The public health or community benefits derived from the use of ARV therapy to decrease the transmission of HIV.
- TasP refers to a method of HIV prevention for people living with HIV. It does not include PrEP, PEP, or ARV-based preventive microbicides, which are designed for HIV negative individuals.
Clearly there is a growing evidence base for TasP. However, multiple elements and considerations are needed for successful delivery of TasP in the community. These include access to testing; acceptance of diagnosis; accessible services; the nature of ARV regimes used; resource limitations; competing priorities; the impact of stigma; treatment adherence and the retention of people in long term care. In addition, for TasP to work at population level, a number of things need to be considered and be in place. There are possibly more questions than answers here! For instance, should TasP include HIV testing for all patients in all healthcare settings? And should this then be combined with treatment offered at any CD4 count? There also needs to be increased treatment uptake in hard to reach groups and changing policy, from deferred to early treatment.
HIV Prevention: Conception, Pregnancy and Infant Feeding
Dr Phillip Hay from St George’s Hospital then presented on my favourite subject. He reminded us that the rates of vertical transmissions are low when mum is on HAART (Highly Active Anti Retroviral Therapy). Although the aim is to achieve zero transmissions, there are a number of circumstances where transmission can occur. These include taking treatment too late, i.e. when transmission has already occurred; missing doses; not adhering – including when treatment is not well tolerated and where there are problems with reduced levels of drugs. This can happen in pregnancy and has been reported among some women taking protease inhibitors.
Dr Hay looked at what needs to be considered when prescribing ARVs for pregnant women living with HIV. These include the fact that women requiring ARVs for their own health need to start immediately. Other considerations can include the mother’s CD4 count and their risk of acquiring opportunistic infections.
Dr Hay discussed the advice given to sero-different couples wishing to conceive. For couples where the woman is HIV positive, the current recommendation is to include self-insemination during the fertile period of her cycle. This is done using quills, syringes and sterile containers. Couples are also advised to have fertility investigations if no success after 6-12 months of self-insemination. This should be done sooner in women above the age of 35; those with irregular cycles and those with a history suggestive of tubal disease. For couples where the man is HIV positive, then assisted conception is safest. Although transmission risk per USI (Unprotected Sexual Intercourse) is reported to be between 0.03 and 0.001%, the risk is significantly reduced if the man has a viral load below 50 copies. This risk is further reduced by limiting exposure to the woman’s fertile period as well as ensuring that all genital tract infections are treated.
The presentation covered a lot more, including the importance of routinely screening women for genitourinary tract infections both at presentation as well as re-screening in the third trimester.
Something that has always interested me is the issue around whether PrEPC (Pre Exposure Prophylaxis for Conception purposes) offers any added benefit, if the SWISS statement conditions are in place..
Dr Hay summarised a modelling study entitled Benefits of PrEP as an adjunctive method of HIV prevention during attempted conception between HIV-uninfected women and HIV-infected male partners: A modelling approach. R.Hoffman et al., which concluded that, based on the author’s input into their model, PrEP provided little added benefit if the man is on ARV; if USI is limited to the ovulation period only and if STIs are diagnosed and treated in both partners.
As regards infant feeding, although the BHIVA guidelines recommend not breastfeeding, women who strongly wish to breastfeed and who willingly engage in healthcare can now be supported to breastfeed. This should, of course be coupled with close monitoring, regular testing and be based on individual patients. In developing countries where there is no constant supply of formula feed, clean water and sterilising equipment, the WHO (World Health Organisation) recommend breastfeeding as the safer option and in particular if mum and baby are on ARVs and mothers breastfeed exclusively.
Given the shift in management with the BHIVA guidelines, the question arises, will HIV women living with HIV will be able to breastfeed in the future? The answer is not yet conclusively known although there are a number of studies in Africa are looking at the safety of breastfeeding in women given HAART for six months post-delivery or with extended infant prophylaxis. I for one am certainly watching that space!