The approval is an unambiguously good thing—or so you would think. The saliva test in question, made by OraSure Technologies and known as OraQuick, costs less than $60 and takes just 20 minutes to self-administer. According to statistics an FDA advisory committee presented at a hearing in May, it holds the potential to prevent the transmission of more than 4,000 new HIV infections in its first year of use alone. That would be about 8 percent of the roughly 50,000 new infections we currently see annually in the United States. (About 1.2 million people in the U.S. are now living with HIV, according to the Centers for Disease Control and Prevention, of whom about 20 percent don’t realize they have it. Since the epidemic began in the early 1980s, about 1.1 million people have been diagnosed with AIDS, and more than 619,000 have died from it.)

The scandal is that the approval of a rapid home test for HIV did not occur until last week—about 24 years after the FDA received its first application seeking permission to market one.

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The big advantage of a home test over a clinical test is confidentiality. HIV infection in this country has historically been associated with homosexuality and intravenous drug use, among other causes. By going to a clinic or family doctor’s office and asking for an HIV test, the patient placed his privacy at great risk. And since AIDS was initially fatal and untreatable—the “gay plague”—there was hysteria about contracting it. People with HIV had reason to fear employment discrimination and social shunning of all kinds.

At the same time, it was crucial that people at risk get tested so that they could take steps to avoid spreading the disease. The rapid home test seemed to offer a discreet, inexpensive, convenient option.

In late 1987, a company called University Hospital Laboratories, run by businessman Elliott Millenson, submitted an application seeking approval of a rapid home blood test for HIV. In March 1988, however, the FDA declined to accept it for filing—the ministerial act that ordinarily initiates the long regulatory process that leads to approval. Instead, it published a series of prerequisites for future applications seeking approval for any HIV diagnostic test which preemptively forbade rapid home tests. The only test applications that would be allowed to even enter the approval pipeline would be those that would be performed in a clinical setting.

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It’s easy to see the legitimate, public-health motivations behind such a rule. There was great concern that the patient receive proper counseling, both before and after the test. The patient needed to appreciate the possibility of false positives, so he wouldn’t panic unnecessarily if he got one. He needed to appreciate the danger of false negatives, so he wouldn’t become reckless, endangering sexual partners. And he needed to understand the options and support groups available in the event he received a true positive. (On top of all these concerns, many AIDS activists at the time were opposed to almost any form of HIV testing out of fear that results could be used to ostracize and persecute HIV-positive people—though one hopes that public health concerns were paramount to the FDA, rather than political pressure and hysteria.)

Still, the approach the FDA took—to reject out of hand all research into even the feasibility of rapid home testing—was ill-advised. Why not allow researchers to do trials to see if the apprehensions surrounding home testing were empirically justified? Why discourage medical device companies from even exploring the question and trying to mitigate the dangers? At best, the ban was paternalistic. Out of concern that some people might respond emotionally and irrationally to the extremely valuable information a home test could provide, everyone was deprived of that option and forced to go to a clinic instead. (This was so even though clinics were not private, more expensive, less convenient, and plenty of people who went to them ended up receiving no counseling or perfunctory counseling of uncertain value.)

And even if the FDA’s ban on considering home testing kits might have been defensible in 1988, it became less so as each year passed—as drugs become available to treat AIDS, as fears became less hysterical, and as political opposition abated and, in many cases, morphed into support. Yet the years did pass—17 of them—before the FDA in 2005 effectively lifted its ban and started considering applications for HIV home testing kits. It then took another seven years for the OraQuick test to wend its way to the approval finish line—the journey it completed last week.

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To be sure, the statistics suggesting that OraQuick might avert more than 4,000 HIV infections in its first year are squishy. It could be less. It might be more. But whatever the true figure turns out to be, we need to remember that even the OraQuick test, because of the FDA’s long opposition to home rapid tests, is not a state-of-the-art procedure. It’s been in use by healthcare professionals for eight years already. The FDA says that OraQuick’s “window period” is 90 days, meaning that infected people should not expect to see a positive result if they were infected less than 90 days before they give themselves that test. By today’s standards, that’s a wide window. There are other rapid tests available today—which have already won FDA approval, though, again, only for use at clinics—which have window periods as short as 12-26 days.

Window periods are important, since people are most infectious right after they are first exposed to the HIV virus. More than half of HIV transmissions are believed to pass from an infected person to a new victim during the infected person’s first 60 to 90 days of exposure.

So if OraQuick might avert 4,000 new infections this year, imagine the number that could have been prevented if a state-of-the-art test had been approved last week.

And now imagine the number that could have been averted if a rapid home test of any description had been approved five years ago.

Or ten.

Or 15.

Or 20.

Or 24.

That’s the scandal.