When the Centers for Disease Control and Prevention (CDC) dramatically broadened its HIV screening recommendations in September 2006, many healthcare policy experts applauded the move, pointing out that roughly 250,000 Americans are unaware of their HIV status. And there is no question that a large percentage of these individuals are unknowingly passing the disease on to others. However, a new analysis of the revised recommendations-which call for opt-out HIV screening for all individuals aged 13-64, without the need for risk assessment or counseling-raises serious questions about whether a more targeted approach to screening that zeros in on high-risk groups and regions might be more effective.
In fact, the new analysis, by David Holtgrave, PhD, an expert on HIV prevention at the Johns Hopkins Bloomberg School of Public Health in Baltimore, suggests that for the same amount of dollars required to carry out the CDC's broad recommendations for opt-out screening, a more targeted HIV screening and counseling approach could identify more than three times as many HIV cases, and it could prevent four times as many new HIV infections as the CDC's strategy.
The provocative report, which appears in the June PLoS Medicine, has generated considerable discussion about the relative merits of various testing strategies. In fact, rather than opting for one strategy or another, many experts contend that the best approach may well involve implementing a number of different strategies simultaneously.
Targeted approach may offer dividends
Holtgrave, who used to head the CDC's division of HIV/AIDS prevention, decided to take a closer look at the CDC's new HIV screening recommendations because no one seemed to know how much an opt-out testing program would cost to implement nationwide and what the specific consequences of implementing such a program would be. "I thought it was really important to try and do some analyses to get a sense of those two issues . . . and whether there are other policies that might, perhaps, be even more effective or more efficient in trying to achieve the same ends," he says.
Consequently, using basic methods of cost-effective analysis, Holtgrave considered four scenarios. First, he calculated what it would cost to implement the CDC's opt-out HIV testing strategy, a policy that calls for routine testing, but with the option for patients to decline. Then he considered the CDC's testing strategy with the added caveat (or behavioral offset) that, in the absence of any HIV counseling, a certain percentage of people who test negative for the virus might continue to engage in risky behavior, thereby eventually resulting in infections.
The third scenario that Holtgrave considered looked at what the costs and effect of routine HIV testing would be if everyone also received pretest counseling and risk assessment. And the fourth scenario considered the costs and effect of an HIV testing and counseling approach whereby high-risk groups, urban areas, and healthcare settings known to have populations with at least a 1% prevalence of HIV would be targeted for HIV screening and counseling.
What Holtgrave concluded was that for the same $864 million that it would cost to implement the CDC's recommended opt-out testing program, a targeted approach that included both testing and counseling would be far more effective at both diagnosing new cases of HIV as well as averting new transmissions.1
Risk-based screening presents problems
Given the dramatic differences between opt-out testing and targeted testing and counseling in Holtgrave's calculations, it is curious that a targeted testing and counseling approach is pretty much what the CDC had recommended for a decade before broadening its recommendations last fall.
However, those recommendations were never fully implemented-perhaps because the CDC never had an $864 million budget for the approach, although Holtgrave points out that all of those funds need not come from public resources. Nonetheless, the CDC broadened its recommendations with the hope that more providers and healthcare settings would implement HIV screening policies without a burdensome requirement for counseling, and that more people would benefit from being diagnosed earlier on in the course of the disease, according to Bernard Branson, MD, from CDC's division of HIV/AIDS.
"Our concern was that [the earlier CDC recommendations for targeted screening] were never implemented," says Branson. "The other issue is we have evidence from several studies indicating that targeting on the basis of risk misses about half the people who are HIV infected."
Branson also suggests that Holtgrave's conclusions with regard to the effects of HIV counseling may be overly optimistic. "To be effective, counseling has to be relatively structured, people have to be trained, and there has to be quality assurance," he says. "The question is whether that is feasible with a large group of providers in a variety of circumstances."
Prevention delivers cost-savings
Holtgrave acknowledges that funding has never been available to fully carry out either the targeted approach to HIV screening and testing he outlines in his study or the opt-out testing strategy recommended by the CDC. However, he emphasizes that policymakers should consider the huge savings that could potentially be achieved by preventing new infections and transmissions.
"It is very legitimate to say that for every infection averted, we save somewhere between $200,000 and $300,000 over the course of a lifetime, depending on whose paper you take from the literature as offering the best estimate of the cost of treatment," he says, noting that when you do the math, both the opt-out and targeted screening and counseling strategies outlined in his study are either cost-saving or very close to cost-saving.
1Holtgrave D. "Costs and Consequences of the US Centers for Disease Control and Prevention's Recommendations for Opt-Out HIV Testing." PLoS Medicine 2007; 4:e194