Celebrated aids doc Brian Gazzard made headlines earlier this year when he kicked off treatment-conservative Britain’s first-ever program to give HAART -- with a nuke or non-nuke combo -- to folks brand-newly HIV positive. By treating within three months of infection while the immune system is still intact, Gazzard says, HIVers may not only spare the protease inhibitors but can stop their combo after 12 to 18 months. “The little bit of virus left may then be controlled by the immune system,” Gazzard says. And while similar small experiments are being conducted by cutting-edge U.S. researchers, Gazzard’s is the only one set to enroll large numbers of civilians.
The trick, however, is how to catch these new infections in time. While Gazzard is not recommending it, one solution would be to persuade all high-risk folks -- gay men, drug users, sex workers -- to test every three months. But lacking any such community standard, technology may hasten what culture cannot.
The standard ELISA test detects HIV antibodies in the blood within three to four weeks of infection. A less sensitive (“detuned”) version, however, can ID antibodies only once reproduction has lasted 120 days. But by combining the two tests, a more precise pinpointing of infection is possible. For example, if a person tests positive on the standard but negative on the detuned, the infection is more than three weeks but less than three months old.
Another screening technique slouching its way to approval is a heat-treated p24 antigen assay. Less costly than the HIV PCR test -- which, like p24, tests for HIV itself rather than antibodies, and so can diagnose within a week or less of infection. This new diagnostic has equalled or surpassed the sensitivity of PCR.
If the argument against more frequent HIV testing is financial, the new p24 test might offer the means for stepped-up screening. And if Gazzard’s hypothesis is correct, routine quarterly testing followed by a short-term course of HAART could dramatically improve our ability to control HIV.