On Monday, I had the pleasure of attending an event hosted by the Gates Foundation called “Polio Eradication and the Power of Vaccines” hosted by Bill Gates at the newly restored Roosevelt House here in New York. At the event, Bill Gates released his 2011 Annual Letter from the Gates Foundation. The main focus of his letter – and of this event – was on polio eradication. Also present at the event were historian cum-author David Oshinsky, representatives from the Sabin Institute, the WHO, and – oddly – a very uninformed Diane Sawyer, who hosted the panel discussion during the event.
The story about polio eradication is a long complicated one. Launched in the late 1980s, buoyed by the successful smallpox eradication program, the international effort had as a goal to eradicate the disease globally. Eradication, as opposed to eliminate or control, means to eliminate it everywhere in the world. It is worth pointing out that eradication is an extremely difficult undertaking and just because one disease has been successfully eradicated, it does not mean that others will be as well. Epidemiologists have argued that some diseases, including some diseases for which global eradication efforts have been launched in the past, are not biologically eradicable (if that is even a word). For example, if there are non-human reservoirs of the infectious agent the agent could easily be reintroduced making eradication nearly impossible. This appears to be true for both malaria, yellow fever, and yaws – all three of which have been targets of failed global eradication efforts. Eradication efforts against these agents are unlikely to be successful if one takes true eradication as the goal.
Fortunately polio is biologically eradicable – in fact one strain of the virus has already been eradicated. Plus, also like smallpox, there are effective vaccines available to target polio, which was the reason why smallpox could have been eradicated. But although we have a vaccine against polio it is not as effective as the smallpox vaccine. In general, we need to give 3 doses of the vaccine and even then we don’t get full protection. There are different strains of the virus circulating and not all vaccines are equally effective against all of the vaccines. Plus, in rare cases, the use of the live version of the vaccine can also cause a mutated and virulent form of the virus – using the live polio virus has been described by some as using fire to fight fire.
Perhaps more importantly, however, is the fact that polio is a largely invisible disease. Most people who get polio are largely asymptomatic. They might have flu like symptoms but for the most part it is impossible to know when someone is infected or not – smallpox victims were easily detected from the rash and poxes that appeared on their body. Only a small fraction of those infected with polio develop paralysis or more severe symptoms. So for every reported case of polio there are literally hundreds or thousands of undetectable infections. By the time we can respond using supplementary immunization – the disease has likely spread.
Does that mean that polio should not be targeted for eradication? There has been a lot of chatter about this this past week, including some comments from experts like Donald Henderson’s whose opinion on this matter I take very seriously. The truth is we don’t know – no one, no matter how much of an expert you are on this matter knows for sure. It is feasible from a biological standpoint, but challenging due largely to issues related to poor health infrastructure in endemic countries, weak institutions, and conflict – stuff public health has not done a great job addressing in the past. Polio has been eliminated in a number of geographic regions around the world but that does not mean it can be eliminated everywhere. But the simple truth is polio will never be eradicated if we don’t try. Plus, given the progress that has been made to date, there may never be a better time than now to try.
Polio eradication is the perfect example of what economists call a public good – while most of us will benefit from polio eradication in some way, the truth is that the benefits to most people will be very small. As such, very few of us have the incentive to pay for this and so we won’t. This is a big reason why I disagree with what author David Oshinsky proposed during his talk on Monday – let’s replicate the March of Dimes efforts from 50 years ago in the United States to raise money for polio eradication. People don’t see polio anymore and as such there is very little constituency to support such efforts. Instead, I believe, it is up to governments, and fortunately for us, rich computer geeks to pay for this effort. We should be thankful, and not be too critical of Bill Gates on this issue. Polio eradication efforts were floundering a few years ago. It is because of him, and his tireless efforts that we are even talking about polio eradication today.
It has been estimated that it will cost about $1 billion a year for the next few years to move ahead with the polio eradication efforts. Some have argued that this is not a lot of money because, for example, Americans spend $18 billion a year on dog food. But that is not the right way to look at this issue. It is a lot of money. The IHME estimated that in 2010 the world allocated about $25 billion a year for development assistance for health, what will ultimately finance most of the eradication efforts. So it is a lot of money in that perspective. Some have argued that this cannot be justified on the basis of disease burden, but again this is not the right comparator. Eradication needs to be considered in a dynamic sense, investments today may lead to cost savings in the long run (actually, I believe all development assistance efforts should also consider the long-run). Investments in polio eradication are a risky investments that may or may not pay dividends in the future. We don’t know if it will be successful, we don’t know if and when we might actually be able to cease polio vaccinations – where most of the savings will come (in fact, we already know that we will likely need to switch from OPV to IPV in the near future and that may need to continue to vaccine for a long time due to that fact that some people continue to shed polio virus and will for years to come).
Bill Gates comes from a different world – he is not a public health person at heart – he is an entrepreneur. He became the worlds richest man not by playing it safe – but by taking risks. This approach has carried over to his work at the Foundation. His donations are like an investor’s portfolio with a balance of safe and risky investments. Polio eradication is certainly one of the risky investments but the high-risk-high-reward model has paid off for him in the past, and it might play out here as well. Of course, we should not just let the mission of one individual highjack the global public health apparatus but I truly believe that this is one program where it might be worth taking the risk.Share on Facebook