The Challenge

Holden Maeker, PhD, Director, Human Immune Monitoring Center (HIMC)

Developing successful vaccines to eradicate infectious diseases in the developing world

Vaccines save millions of lives each year and are among the most cost-effective health interventions ever developed. Immunization has led to the eradication of smallpox, a 74 percent reduction in childhood deaths from measles over the past decade, and the near-eradication of polio. Illnesses like mumps and measles are now preventable.

Despite these great strides, there remains an urgent need to reach all children with life-saving vaccines. One in five children worldwide are not fully protected with even the most basic vaccines.

Successful Development of New Vaccines Remains a Challenge

Scientists have been stymied in their efforts to fight diseases such as HIV and malaria. In part, this is because large-scale clinical trials can cost hundreds of millions of dollars and can take up to 10 years to determine the success--or often failure–of a vaccine candidate.

Efforts to develop vaccines against some of the most devastating diseases that are current in the developing world, HIV, TB in adults, Malaria, and Dengue have all largely failed or been only partially successful.

In addition, malnutrition and other factors in developing countries significantly reduce the efficacy of vaccines that work well in developed countries (such as Polio, Rotavirus etc.). It is clear that we need to design more sophisticated vaccines and vaccination strategies, and for this we need a better understanding of the overall immune response to a particular disease in terms of what constitutes broad correlates of protection.

Further Study Will Reveal the Characteristics of Successful Vaccines

We need a more sophisticated and evolved understanding of what makes an effective vaccine and what the key biomarkers are that would allow us to predict with greater accuracy which new vaccine formulations are likely to be successful, especially in the developing world. This requires both the employment of new assay methods, to ongoing and future vaccine trials, and the development of additional technologies and analysis methods.

There is also a great deal more to be learned about various diseases, particularly about why some individuals are resistant and others are not. Natural history studies and small but highly focused experimental medicine studies, coupled with advanced technology and analytical methods that comprehensively characterize the host-pathogen interaction, should yield important new insights.