Sarah Rowland-Jones: HIV and children in Africa
Q: You work on HIV; what are the most important lines of research that have developed over the past five or ten years?
SR-J: For many people in the developed world, treatment options are so good now that for much of the HIV infected population HIV has become a chronic disease like diabetes or high blood pressure and can be managed quite well over a long period. But my interests are much more in HIV in the developing world where, even though treatment access has improved a great deal, there is still more new infections in sub-Saharan Africa each year than there are drugs available for the people who need it. So there is still a great need to think about vaccine development and there have been ups and downs in vaccine development over the last few years. The human studies have largely been disappointing, but to everyone surprise a vaccine which no one really expected to work showed some signs of efficacy in a big study in Thailand two years ago. We still don't know exactly how it worked but it has encouraged the field to think that at least it might be possible. There are now much more encouraging signs in animal experiments as well. So the field at the moment is feeling that HIV vaccine development is possible, but we are still quite a long way off that.
Q: How does HIV affect children in Africa?
SR-J: It behaves very differently in children and this is something that perhaps hasn't had enough attention. Whereas adults, once they get infected, often have a lot of virus in the blood circulating soon after infection which they then control down to low levels again, children maintain very high levels of HIV in the blood for at least the first 2 years after infection. They show almost no evidence of controlling the virus in that time and as a consequence disease progression if they aren't treated is very rapid. In a study we did in Nairobi something like 50% of the children were dead by the age of 2.
Q: How can we help?
SR-J: We have become particularly interested in the few that make it through childhood and into adolescence. This is a surprise because the rates of death are so horrifyingly high in young children; a proportion of children nevertheless make it into their teens. We have been working with a group in Harare to try and understand better how this small number of children make it through into their teens and also how best to help them. In the longer term we'd like to set up a Centre of Excellence in Harare specifically to highlight this problem of HIV in adolescence in children who were infected at birth but not previously diagnosed, to understand better about how to treat them and prevent what seemed to be very serious and life threatening complications of being infected with HIV for so long without treatment.
Q: Can you tell us about your research on the second strain of HIV in Africa?
SR-J: This came about largely because I spent four years working in West Africa seconded from the department in the MRC labs in the Gambia where I was Research Director. The labs there have a big interest in HIV-2 infection which doesn't hit the headlines like HIV-1 does because much smaller numbers of people are infected and it seems largely restricted to West Africa and in particular to places with Portuguese connections for reasons that are not entirely understood but probably relate to the war of independence in Guinea-Bissau against the Portuguese. HIV-2 is fascinating because, whereas everybody with HIV-1, if they are not treated as far as we know will eventually develop disease and die, there are quite a large number of people with HIV-2 who literally die of old age and never develop any symptoms of disease. Some of our study cohort in Guinea-Bissau are ladies in their seventies and eighties who are completely well and have had HIV-2 for two or three decades. Yet the people who do develop disease develop it in a way that you couldn't distinguish from HIV-1 infection. We are trying to understand the differences between those two groups. As far as we understand at the moment it is the immune response and not the virus that is the key to trying to understand protective immunity to HIV.
Q: How does your research fit into Translational Medicine within the department?
SR-J: The ultimate aim of the work is to try and understand protective immunity against HIV in a way that would help both design and also to evaluate new vaccine candidates. I work quite closely with investigators like Andrew McMichael and Tom Hanke, who are leading the HIV vaccine development programme in Oxford, and with Lucy Dorrell who is testing therapeutic vaccine strategies for HIV infection. I am particularly interested to work with Lucy and Tom over a HIV-2 therapeutic vaccine because the data we have at the moment suggests immune control is really important for controlling HIV-2. A therapeutic vaccine might be particularly useful in that context. I also work with the investigators in the overseas unit's particularly in Kilifi over studies of HIV in children.