Aids drugs not only keep people alive but reduce the chances of the syndrome spreading, according to a study published on Monday, which makes a strong case for stepping up the roll-out of treatment in affected countries.
About five million people are now on antiretroviral drugs, but 10-million more in the developing world are in need of them. The G8 group of industrialised nations made a commitment to universal access at their Gleneagles summit in 2005, but the cost of achieving it is high — not just in terms of the price of drugs but also the supply and distribution systems and clinics that are needed.
The paper, though, from leading Aids researchers in Canada, suggests that there are greater benefits to medication than are generally added into the equation. Drugs are not only for treatment, but also for prevention, it says.
Professor Julio Montaner, director of the British Columbia Centre for Excellence in HIV/Aids in Vancouver, and colleagues point out that no cure or vaccine appears likely in the foreseeable future. Strategies to prevent the spread of HIV/Aids, however, have had limited effect due to various factors including poor implementation, insufficient support and logistical difficulties.
“As a result, the global effect of HIV/Aids continues to grow,” they write in their paper, published online by the Lancet.
“In 2008, an estimated 33,4-million people were living with HIV, there were two million Aids-related deaths and an alarming 2,7-million new HIV infections occurred.” As a result, they say, the UN has called for an urgent redoubling of efforts against the virus.
Highly active antiretroviral therapy (Haart) — the triple drug combination that suppresses the viral load in the body — has saved at least three million years of life in the United States in the decade to 2006, they write.
People who were HIV-positive on Haart could expect to live for roughly two-thirds the lifespan of uninfected people. But because the virus can disappear to undetectable levels, although it is still present, experts began to wonder whether people on the drugs would be less infectious also.
Montaner and colleagues tested this thesis in British Columbia, but say their findings are applicable elsewhere in the world. Between 1996 and 2009, they say, the number of people on Haart rose from 837 to 5 413, but over the same period of time newly diagnosed infections fell by more than half, from 702 to 338 a year.
For every 100 patients put on drug treatment, new HIV diagnoses fell by 3%. When the use of Haart expanded, from 1996-2000 and from 2004-09, diagnoses fell. When the numbers being put on drugs remained fairly stable between 2001-03, so did the rate of diagnoses — a small fall of 2% compared with a drop of 30% and 17% in the earlier and later time periods.
The fall in HIV diagnosis was not connected with safer sexual behaviour, they say, because rates of sexually-transmitted infections went up in the last 15 years of the study.
Treatment 2.0
“Our results support the proposed secondary benefit of Haart used within existing medical guidelines to reduce HIV transmission … [and] provide a strong rationale for re-examination of the HIV prevention and treatment dichotomy, as has been strongly advocated by the UN joint programme on HIV/Aids (Unaids) as part of a comprehensive combination prevention strategy. Furthermore, our results should serve to re-energise the G8’s universal access pledge as a means to curb the effect of Aids and the growth of the HIV pandemic,” the authors write.
UNAids last week announced a strategy which it calls Treatment 2.0, that aims to get drugs to the 10-million who are still in need. The agency hopes to engage drug companies in creating simpler, cheaper pills to reduce the costs. The results announced on Monday will strengthen the argument for improving access to drugs and may help persuade cash-strapped donors that treatment, as well as traditional prevention tools such as education, deserves extra funds.
In a commentary with the Lancet paper, two more HIV experts, Dr Franco Maggiolo and Dr Sebastiano Leone from the division of infectious diseases at Ospedali Riuniti in Bergamo, Italy, say: “While waiting for an effective vaccine, experiences such as those reported today should be strongly considered by clinicians, national and international agencies, policy makers and all parties involved in the development of treatment guidelines, because the population-based dimension of Haart might play an important part in the future control of the HIV epidemic.” – guardian.co.uk