Two years ago, Melinda and I challenged the health field to set a goal of eventually eradicating malaria. Because it is such a widespread disease, the foundation has backed a number of different types of innovations. In 2005 we helped fund a medium-risk pilot project in Zambia to test having most people in an area sleep under insecticide-treated bed nets and spray the inside of their house with insecticides. These interventions have proven to reduce malaria substantially, and other partners have now taken the lead on the large-scale delivery of these interventions. There has been a dramatic increase in bed net usage thanks to donations from individuals (some through church organizations and Nothing But Nets), The Global Fund, and rich governments. The countries that have had these interventions in wide-scale use for several years are seeing large reductions in malaria deaths: Rwanda has seen a 45 percent decline, Zambia 50 percent, Cambodia 50 percent, Eritrea 80 percent. These interventions are being scaled up rapidly, which will have a big impact.
But malaria is a particularly tricky disease. The current tools alone will not be enough to eradicate it, so we are funding new medium- and high-risk innovations. For example, we are funding the invention of new insecticides for use on bed nets, because some mosquitoes are developing resistance to the current one. And because bed nets aren’t accepted in some locations, we are also investing in new ways of delivering insecticide in a house—perhaps using candles or chemical sticks. We are also investing in cheaper ways to make the drugs we already have, as well as new drugs because we know the parasite will develop resistance to the current treatments.
Finally, to eradicate the disease, we will almost certainly need a malaria vaccine, which is the highest-risk malaria work we fund. The key here is that researchers are pursuing a lot of different ideas, so that if one fails, there are still several other options. One partially effective vaccine candidate, known as RTS,S, has started its Phase III trial, which is an important step. Other vaccine approaches are at an earlier stage and they also look very promising. Scientists are combining some of these other vaccine efforts with RTS,S to raise its effectiveness and duration, an approach that could lead to a highly efficacious vaccine in 8 to 15 years.
But malaria is a particularly tricky disease. The current tools alone will not be enough to eradicate it, so we are funding new medium- and high-risk innovations. For example, we are funding the invention of new insecticides for use on bed nets, because some mosquitoes are developing resistance to the current one. And because bed nets aren’t accepted in some locations, we are also investing in new ways of delivering insecticide in a house—perhaps using candles or chemical sticks. We are also investing in cheaper ways to make the drugs we already have, as well as new drugs because we know the parasite will develop resistance to the current treatments.
Finally, to eradicate the disease, we will almost certainly need a malaria vaccine, which is the highest-risk malaria work we fund. The key here is that researchers are pursuing a lot of different ideas, so that if one fails, there are still several other options. One partially effective vaccine candidate, known as RTS,S, has started its Phase III trial, which is an important step. Other vaccine approaches are at an earlier stage and they also look very promising. Scientists are combining some of these other vaccine efforts with RTS,S to raise its effectiveness and duration, an approach that could lead to a highly efficacious vaccine in 8 to 15 years.
Polio is down to fewer than 3,000 cases a year—a 99 percent reduction in 20 years—but getting rid of the last 1 percent is the hardest part of eradicating a disease. When we increased our investment in polio two years ago, we viewed it as a challenging delivery problem rather than something requiring a new tool, because the oral vaccine worked quite well. Most of our funding has supported innovative approaches to delivery. But when we saw that in some places the oral vaccine wasn’t totally effective, we also funded the creation of new forms of the vaccine, which are targeted at subsets of the three different varieties of polio virus. This is a good example of needing to stay open-minded about the best approach to solving a problem, because the new forms of the vaccine have been critical in the progress that has been made this year.
In last year’s letter I mentioned that there are four countries that account for most of the remaining cases. One was Nigeria, particularly in its northern states, where polio has been especially problematic. In 2009, thanks to new money and political support from some state, local, and traditional leaders, they were able to vaccinate more children in most states. This led to a 50 percent decline in the overall number of cases and a 90 percent decline in the most virulent strain. In 2010, they will need to get the vaccination rate up in every state.
The three other countries—India, Afghanistan, and Pakistan—shrunk the geographical areas affected by the virus. Some of the toughest remaining areas are the ones where the security situation is bad, like parts of Afghanistan and Pakistan.
When outbreaks did occur, countries responded faster and more effectively than they had before. Last year, poliovirus from Nigeria and India spread to more than 15 African countries that had been considered polio-free. But because many countries had begun using better laboratory techniques, they identified the virus quickly and started immunization campaigns right away, which limited the spread of the outbreak. Still, we haven’t gotten these countries back to zero cases yet, especially in west Africa and Chad, where the outbreak is still widespread. I will be traveling to some of these countries to meet with health leaders, and I expect I’ll be able to report even more progress in next year’s letter.
In last year’s letter I mentioned that there are four countries that account for most of the remaining cases. One was Nigeria, particularly in its northern states, where polio has been especially problematic. In 2009, thanks to new money and political support from some state, local, and traditional leaders, they were able to vaccinate more children in most states. This led to a 50 percent decline in the overall number of cases and a 90 percent decline in the most virulent strain. In 2010, they will need to get the vaccination rate up in every state.
The three other countries—India, Afghanistan, and Pakistan—shrunk the geographical areas affected by the virus. Some of the toughest remaining areas are the ones where the security situation is bad, like parts of Afghanistan and Pakistan.
When outbreaks did occur, countries responded faster and more effectively than they had before. Last year, poliovirus from Nigeria and India spread to more than 15 African countries that had been considered polio-free. But because many countries had begun using better laboratory techniques, they identified the virus quickly and started immunization campaigns right away, which limited the spread of the outbreak. Still, we haven’t gotten these countries back to zero cases yet, especially in west Africa and Chad, where the outbreak is still widespread. I will be traveling to some of these countries to meet with health leaders, and I expect I’ll be able to report even more progress in next year’s letter.
There is some encouraging news here. HIV isn’t spreading as fast as it was. The number of new people getting infected with the virus peaked in 1996 at 3.5 million and was down to 2.7 million in 2008. Prevention efforts, like the foundation’s work in India to get sex workers and their clients to use condoms more often, are part of the reason for this reduction. But 2.7 million is still 2.7 million too many, and in some places, the disease rate is still incredibly high. In South Africa, 18 percent of adults are infected, and in parts of the country more than half of the women are infected by the time they are in their mid-20s.
The number of people worldwide receiving antiretroviral (ARV) therapy for HIV increased to 4 million last year, which is a great achievement. In the early years of AIDS, it was not clear whether a large-scale treatment effort would work in Africa. Beginning in 2001, the foundation helped fund treatment in Botswana, one of several projects showing that it could work. The Global Fund and the United States’ PEPFAR program (a $50 billion program to help combat AIDS in Africa) have since taken the lead in scaling up ARV delivery. They are both doing a great job, although there is a lot of concern that limited funding will restrict the number of new patients they can treat.
Treatment is important, but we urgently need innovations to prevent the spread of HIV, which is where the foundation has focused a lot of its efforts. Trials are in progress on pills and gels that we hope will substantially reduce the chance of getting infected. We will begin to see the results from these trials late this year.
Another approach to reduce the spread of HIV is male circumcision. I mentioned in last year’s letter that studies have shown that male circumcision reduces the odds of transmission from a woman to a man by over 60 percent. In areas where transmission is widespread, if you circumcise most of the men over 14 years old you can significantly reduce the spread of HIV. The foundation funded pilot efforts to scale up circumcision, but I viewed it as high-risk because I was doubtful that enough men would volunteer to be circumcised. That is why last December I went to visit Bertran Auvert, a French scientist working in a South African township called Orange Farm. Bertran conducted one of the key studies on the effectiveness of circumcision, and now he has set out to show that doubters like me are wrong.
He and his co-leader, Dirk Taljaard, are modest about their work but, amazingly, they are getting over 750 men a month to come to their facility. They have already circumcised 14,000 men, and within a year they think they will be able to circumcise almost all of the men in the community. It looks like a very high percentage will participate. Bertran’s approach is very efficient, with costs of only $40 for the surgery. Based on this success, a number of facilities are being set up in South Africa and in other countries with high HIV prevalence to do the same thing. In many African countries, if a high percentage of men volunteer for circumcision, it will reduce the number of cases at least 30 percent over time, which shows what an impact a great scientist like Bertran can have.
The major news in AIDS this year, which you may have read about, concerned an HIV vaccine. A trial done in Thailand reported its results in September. The foundation’s biggest spending on AIDS focuses on vaccine work, but we didn’t fund this trial. Although there are several ways of analyzing the data and the vaccine had only modest effects, the results of the trial were good news. They showed the scientific community that a vaccine is possible.
The AIDS community is working on a number of candidate vaccines, many of which show better results in tests on monkeys than the vaccine used in the Thai trial. Since only a few vaccines can be picked for a trial, the community will have to collaborate and figure out which ones should go forward. Although a vaccine for widespread use is still more than a decade away, the scientific progress this year was better than most peopl
The number of people worldwide receiving antiretroviral (ARV) therapy for HIV increased to 4 million last year, which is a great achievement. In the early years of AIDS, it was not clear whether a large-scale treatment effort would work in Africa. Beginning in 2001, the foundation helped fund treatment in Botswana, one of several projects showing that it could work. The Global Fund and the United States’ PEPFAR program (a $50 billion program to help combat AIDS in Africa) have since taken the lead in scaling up ARV delivery. They are both doing a great job, although there is a lot of concern that limited funding will restrict the number of new patients they can treat.
Treatment is important, but we urgently need innovations to prevent the spread of HIV, which is where the foundation has focused a lot of its efforts. Trials are in progress on pills and gels that we hope will substantially reduce the chance of getting infected. We will begin to see the results from these trials late this year.
Another approach to reduce the spread of HIV is male circumcision. I mentioned in last year’s letter that studies have shown that male circumcision reduces the odds of transmission from a woman to a man by over 60 percent. In areas where transmission is widespread, if you circumcise most of the men over 14 years old you can significantly reduce the spread of HIV. The foundation funded pilot efforts to scale up circumcision, but I viewed it as high-risk because I was doubtful that enough men would volunteer to be circumcised. That is why last December I went to visit Bertran Auvert, a French scientist working in a South African township called Orange Farm. Bertran conducted one of the key studies on the effectiveness of circumcision, and now he has set out to show that doubters like me are wrong.
He and his co-leader, Dirk Taljaard, are modest about their work but, amazingly, they are getting over 750 men a month to come to their facility. They have already circumcised 14,000 men, and within a year they think they will be able to circumcise almost all of the men in the community. It looks like a very high percentage will participate. Bertran’s approach is very efficient, with costs of only $40 for the surgery. Based on this success, a number of facilities are being set up in South Africa and in other countries with high HIV prevalence to do the same thing. In many African countries, if a high percentage of men volunteer for circumcision, it will reduce the number of cases at least 30 percent over time, which shows what an impact a great scientist like Bertran can have.
The major news in AIDS this year, which you may have read about, concerned an HIV vaccine. A trial done in Thailand reported its results in September. The foundation’s biggest spending on AIDS focuses on vaccine work, but we didn’t fund this trial. Although there are several ways of analyzing the data and the vaccine had only modest effects, the results of the trial were good news. They showed the scientific community that a vaccine is possible.
The AIDS community is working on a number of candidate vaccines, many of which show better results in tests on monkeys than the vaccine used in the Thai trial. Since only a few vaccines can be picked for a trial, the community will have to collaborate and figure out which ones should go forward. Although a vaccine for widespread use is still more than a decade away, the scientific progress this year was better than most peopl
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