Perspectives in Health Magazine
The Magazine of the Pan American Health Organization
Special Centennial Edition
Volume 7, Number 2, 2002

As it turned out, it was necessary to have two NID a month apart, and to repeat the effort yearly for at least three years, turning Rotary's Polio Plus campaign into a monumental task. As polio gradually came under control, it became important to detect the residual cases. Therefore, a surveillance system was instituted to bring all cases of acute paralysis (technically termed flaccid to distinguish them from strokes) to the notice of health authorities. When cases were found, two stool samples were sent to accredited laboratories to see if the polio virus could be grown. This tedious but vital surveillance task has been absolutely crucial.

Finally, "mop-up" operations, consisting of dwelling-to-dwelling immunization around the last known cases, are the last step toward eradication. Thanks to this quadruple strategy, there have been no indigenous wild polio cases in the Western Hemisphere since 1991, none in the Western Pacific Region since 1997, and none in the European Region since 1998. Even in India, wild polio is now essentially confined to two northern states.

Over the next couple of years, WHO will be concentrating on 10 countries in Africa and South Asia, five of which are conflict ridden and five others "reservoir countries" because of high population density and very poor living standards. The target year for the global eradication of the wild polio virus is 2005.

Although the Polio Plus campaign is a vertical program (as opposed to horizontal programs, which seek to provide primary health care across a broad front), it has broader implications. First, in many cases vitamin A supplements are administered simultaneously. Second, it provides a contact point between remote and disadvantaged rural poor and national health systems, often leading to a greater awareness of other available health interventions.

Global alliance
The experiences of both smallpox and polio show the extraordinary power of the vaccine approach. But what about the present state of play? In 1998, there was a sense that new energies were needed in global immunization efforts. Donor interest in EPI was fading, the vaccine infrastructure in many countries was deteriorating, and research was lagging on new vaccines for diseases occurring only in poor countries.

But as WHO, UNICEF, the World Bank and leading academics were searching for a new dynamic, help came from an unexpected source: William H. Gates III and his wife, Melinda French Gates. The Gates Foundation made an initial pledge of $100 million to a Children's Vaccine Program, at first designed to determine and overcome the chief roadblocks to the introduction of important new vaccines into the EPI. Within two years, the Gates' extraordinary generosity had led to a total of $1.4 billion com-mitted to vaccine-related projects, including considerable research and development funds and a $750 million gift earmarked for a Global Fund for Children s Vaccines, administered by UNICEF. The Vaccine Fund, as it is now known, targets the 74 poorest countries in the world, namely, those with per capita GDP of less than $1,000 per annum. Several countries have added pledges to the fund, and it now stands at more than $1 billion.

After extensive consultation with all stakeholders, the Global Alliance for Vaccines and Immunization (GAVI) was launched in 2000 as an unincorporated alliance of WHO, UNICEF, the World Bank, the Gates and Rockefeller foundations, and other nongovernmental organizations, along with bilateral donors, developing country health authorities and vaccine manufacturers from both developed and developing countries.

The GAVI board was chaired initially by WHO Director-General Gro Harlem Brundtland and is now chaired by Ms. Carol Bellamy, executive director of UNICEF, ensuring commitment of their respective organizations at the highest level.

GAVI has set itself three major goals. The first is to improve infrastructure for immunization in countries where it is inferior through cash grants dependent on a demonstrable increase in vaccination coverage.

The second is to purchase, for selected countries, vaccines beyond the traditional six, primarily hepatitis B, yellow fever and Hemophilus influenzae B, or Hib, for meningitis, pneumonia and septicemia.

The third and longer-term goal is to do applied research and development work for newer vaccines already well down the track, such as against pneumococcus and rotavirus. Already two-thirds of GAVI s target countries have grants and/or vaccine supplies flowing to them. Yet sustainability is a real worry, as the beneficiary countries will gradually have to subsume the costs of the vaccines into their own health budgets.

Future vaccines
Despite the amazing progress of immunological science, there are many diseases for which we do not yet have an effective vaccine. We could see rapid progress in the so-called "low-hanging fruit," those vaccines-in-research whose underlying principles have largely been established and that seem to require relatively straightforward development work to become available. This is probably the case for the A subtype of meningococcus, responsible for horrible meningitis epidemics in sub-Saharan Africa; for rotavirus, an important cause of infantile diarrhea; and for pneumococcus, which will involve major expense because each of many different disease-causing types will need to be included in an eventual vaccine.

It would be surprising if vaccines for these pathogens were not available within five to seven years. Again, we must seek public sector funds for their early introduction.

Somewhat more speculative are vaccines against shigellosis, or bacillary dysentery, a cause of some 800,000 deaths per year, nearly all in very poor countries; and against Helicobacter pylori, the cause of peptic ulcer disease, chronic gastritis and a big proportion of gastric cancers. It is doubtful whether the pharmaceutical industry will come up with sufficient research funding to drive these vaccines all the way to registration. The chances are better for a vaccine against human papilloma virus (HPV), the cause of cervical cancer and genital warts, because industrialized countries have a major interest in preventing these problems.

Continue