Limiting the Spread of AIDS
January 30, 2009
During my discussions about Development-in-a-Box™, I have often made the point that frontier economies progress faster when they have achieved a few pre-conditions that help them attract foreign direct investment. One of the things that investors look for is a healthy workforce. As Americans are well aware, healthcare places an enormous overhead burden on businesses offering insurance for their workers. Even more onerous, however, is the burden of trying to operate a business using people whose health is so poor that they cannot be relied upon. The healthier the workforce the more productive and cost-effective a business can be. One of the developing world’s health scourges is AIDS and the virus that causes it (HIV). The Holy Grail of AIDS researchers is discovering a vaccine that can prevent the spread of the disease; but, according to The Economist, that discovery remains elusive. As a result, healthcare providers are exploring alternative ways to limit the spread of AIDS [“The ideal and the good,” 29 November 2009 print edition].
“It has become a cliché among doctors who deal with AIDS that the only way to stop the epidemic is to develop a vaccine against HIV, the virus that causes it. Unfortunately, there is no sign of such a thing becoming available soon. The best hope was withdrawn from trials just over a year ago amid fears that it might actually be making things worse. As a result, vaccine researchers have mostly gone back to the drawing board of basic research. Meanwhile, the virus marches on. [In 2007], according to UNAIDS, the international body charged with combating it, 2.7m people were infected, bringing the estimated total to 33m. Reuben Granich and his colleagues at the World Health Organisation (WHO), though, have been exploring an alternative approach. Instead of a vaccine, they wonder, as they write in the Lancet, whether the job might be done with drugs.”
The world is filled with adages and the appropriate one here is: “Better is the enemy of good enough.” That is the basic argument of the article. The vaccine may be the ideal, but drugs may be good enough. The article also discusses the fact that the war on AIDS needs to be two-pronged — one prong for helping those already infected and the other prong helping the uninfected remain that way. The “good enough” drug approach can help both the infected and uninfected, but it requires a massive PR campaign and the cooperation of those carrying the virus.
“In the spread of any contagious disease, each act of infection has two parties, one who already has the disease and one who does not. Vaccination works by treating the uninfected individual prophylactically. Since it is impossible to say in advance who might be exposed, that means vaccinating everybody. The alternative, as Dr Granich observes, is to treat the infected individual and thus stop him being infectious. For this to curb an epidemic would require an enormous public-health campaign of the sort used to promote vaccination. But that campaign would be of a different kind. It would have to identify all (or, at least, almost all) of those infected. It would then have to persuade them to undergo not a short, simple vaccination course, but rather a drug regime that would continue indefinitely.”
Anyone familiar with the history of AIDS knows that treating it has always been complicated by the fact that those who carry the virus are often treated as social pariahs. As a result, many infected individuals never come forward. If the social stigma of having AIDS remains, it could cripple any effort “to identify all (or, at least, almost all) of those infected” and then persuade them to undergo treatment. As the article notes, this leads to the overriding question about whether such an approach could work — even in principle.
“It is this [question] that Dr Granich and his colleagues have tried to answer. Using data from several African countries, they have constructed a computer model to test the idea. In their ideal world, everyone over the age of 15 would volunteer for testing once a year. If found to be infected, they would be put immediately onto a course of what are known as first-line antiretroviral drugs (ARVs). These are reasonably cheap, often generic, pharmaceuticals that, although they do not cure someone, do lower the level of the virus in his body to the extent that he suffers no symptoms. They also—and this is the point of the study—reduce the level enough to make him unlikely to pass the virus on. For the 3% or so of people per year for whom the first-line ARVs do not work, more expensive second-line treatments would be used. When Dr Granich crunched the numbers through the model, he concluded that if this scheme could be implemented, it would do the trick. The rate of new infections (now 20 per 1,000 people per year) would fall within ten years of full implementation to one per 1,000 per year. Within 50 years the prevalence of HIV would drop below 1%, compared with up to 30% at the moment in the worst-affected areas.”
So, in principle, the approach could work. A favorite saying of many military strategists is “that no plan survives first engagement with the enemy.” As aside note, according to Ralph Keyes, “This observation actually originated with Helmuth von Moltke in the mid-nineteenth century. The Prussian field marshal’s version was not so succinct, however. What von Moltke wrote was ‘Therefore no plan of operations extends with any certainty beyond the first contact with the main hostile force.'” The question in the war on AIDS is whether the drug plan could survive first contact with reality. That’s the question next addressed in the article.
“Whether such an approach could be made to work in practice—and if it could, whether it should—are two other questions. The existing plan for combating HIV centres on saving the lives of those already infected. The intention is to make ARVs available to everyone who needs them, in rich and poor countries alike, by buying the drugs cheaply and building the infrastructure of doctors, nurses and clinics to prescribe and provide them. ‘Needs’, however, is defined as ‘at risk of developing symptoms’. People with HIV often remain asymptomatic for years, and conventional wisdom is that treating such people brings little clinical benefit while exposing them to unpleasant side effects such as nausea, vomiting and diarrhoea. Even vaccination bothers some medical ethicists because, although it does protect the vaccinated individual, governments promote it in order to create ‘herd immunity’—from which the unvaccinated will also benefit. Treating asymptomatic carriers of HIV causes greater qualms if it brings no benefit to the people actually taking the medicine. However, Kevin De Cock, one of Dr Granich’s colleagues, points out that the latest research suggests such people are not as asymptomatic as had once been thought. They may suffer from illnesses such as heart, kidney and liver diseases and cancers that are not classical symptoms of AIDS. Indeed, a recent study suggested that deferring treatment until classical symptoms appear increases the chance of someone dying by 70%. If that result is confirmed, it would change the ethics completely. It would also make it easier to persuade people to come in once a year for testing at their local clinic, even if they felt well. And it would create pressure for the current policy to be reviewed anyway, so that something like the scheme Dr Granich and his colleagues have been investigating might end up happening by default.”
Ethics aside, the next big question is whether the international community could afford to pay for the drug program.
“If the scheme were implemented (and the WHO is at pains to point out that this paper in no way indicates a change of policy), it would be more costly to begin with than the existing plan of universal access. However, that would change over the years, as the caseload fell. This seems, therefore, to be an approach worth exploring. AIDS doctors are not so spoilt for options that they can afford to ignore new ones. Employing the logic of vaccination using proven drugs may be an idea whose time has come.”
In other words, the question is not whether the international community can afford the program but whether it can afford NOT to support it. A well-educated and healthy workforce is the most important natural resource that any country can possess. Companies that value their employees normally do well. Countries that value their citizens also find themselves climbing the economic ladder. The turning point in the battle against AIDS will take place when there is more social stigma attached to those unwilling to help AIDS victims than there is to the victims themselves. The developed world has demonstrated that people infected with HIV can live long and productive lives. Victims in the developing world deserve that same chance.