The active promotion of immediate treatment after suspected HIV transmission to minimise the risk of infection may be doing more harm than good, claim senior doctors in Sexually Transmitted Infections.
UK and US guidelines advocate prompt antiretroviral treatment for those who think they may have become infected with the virus after potentially risky sex. The procedure is known by its acronym of PEPSE in the UK and nPEP in the USA.
It needs to be given within 72 hours of suspected exposure and continued for 28 days.
But the effectiveness, impact on changing 'risky' sexual behaviour, and the financial implications of this policy have never been properly evaluated, say the experts from two sexual health clinics.
PEPSE was given to 48 patients in 2003 and 119 in 2004 in one central London clinic, they say.
And the projected cost for just one clinic in 2005 is expected to be in the region of £180,000, at a time when sexual health clinics are struggling to cope with demand for services and to contain the associated rising costs.
"We are concerned that there is pressure to make PEPSE available for homosexual men regardless of cost and without proper consideration of possible negative consequences on service delivery and HIV transmission," they write.
"We believe that there is a distinct danger that the promotion of PEPSE could reinforce rising trends in risky sexual behaviour and might add to, rather than lessen HIV transmission," they add.
In an invited response, Dr Martin Fisher at Brighton and Sussex University Hospitals NHS Trust, admits that there isn't a robust evidence base for the policy.
But he says that it would be practically and ethically extremely difficult to conduct the kind of trial that would be required for this. However, two Brazilian studies have suggested that PEPSE does reduce HIV infection.
PEPSE is also given to healthcare workers after occupational exposure, where the absolute risk is lower than that of risky sex between gay men, he says.
PEPSE not only helps to prevent HIV infection, but also offers an opportunity to screen for other sexually transmitted infections. And it may very well act as a 'wake up call,' he suggests, as some studies have shown that it results in less risky behaviour.
While he agrees that the cost of PEPSE is not insignificant at £800 to £1000 a person, it is still much cheaper than providing treatment for HIV infection, which costs up to £1 million, he suggests.
PEPSE, he concludes is "one extra tool in the battle to prevent new cases of HIV infection."
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