HIV pandemic is one of the great failures of modern science. While the identity of the virus that causes AIDS has been known since 1983, and its discoverers have won the Nobel Prize for Medicine, it has not yet proved possible to stop it from spreading.The global extent of the
Vaccine research has hit dead end after dead end, as HIV’s diabolical ability to mutate has confounded every promising candidate, and vaginal microbicides designed to prevent transmission have also disappointed.
Public health interventions such as condoms have worked, but require behaviour changes that can be difficult to achieve.
This failure, however, has been matched with one great triumph: anti–retroviral drugs are extraordinarily successful at containing the virus in patients who are already infected.
Where HIV was once seen as a death sentence, it is now regarded as a chronic condition with which people can live for decades.
There is now a good chance that this success can be exploited to prevent the spread of HIV.
As drugs reduce the amount of virus in the body, they make carriers less infectious, so they have the potential to do much of the job of a vaccine.
The universal testing and treatment programme proposed by Brian Williams has a good chance of delivering a step change in HIV prevention, particularly if combined with safe Sex Education and male circumcision.
Several important hurdles remain, however. First, the approach must be rigorously analysed in randomised trials, to confirm that it can actually work in African settings.
We need to know whether people will accept mass testing, and whether those who test positive will complete their treatment: poor compliance can build drug–resistance and make the problem worse.
There is also the matter of cost. While containing AIDS would certainly pay for itself in the long run, significant up–front investment will be needed.
The sums involved are large, but not that large: Dr Williams compared the estimated $3billion (£2 billion) needed for South Africa with the $30bn cost of the Iraq troop surge.
They are certainly not beyond the combined means of Western and African governments, and philanthropic organisations such as the Bill & Melinda Gates Foundation.
To engage these resources, though, firm evidence of efficacy will be needed. That is why the trials that start soon in South Africa are so important.
Source :Times Online
Tuesday, Feb 21st
Last update:05:44:44 AM IST