From left: Administering polio drops to a child during a visit to a Bini health clinic (Sokoto, Nigeria, 2009); woman delivering
vaccines house-to-house on Immunization Plus Day (Sokoto, Nigeria, 2009).
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.