This post originally appeared on PATH’s Innovation Countdown website here. Reposted with permission.

More than 200 years since Edward Jenner’s first pioneering work, vaccines continue to be one of the most innovative and cost-effective health interventions the world has ever seen. They have already paved the way for dramatic reductions in life-threatening and debilitating diseases in wealthy and many developing countries. But now, thanks to the accelerated development of new vaccines and new ways of improving access to immunization, we have the opportunity to reach every child, no matter where they live.

This is critical because, despite the great strides that have been made in increasing immunization rates, global coverage is still much lower than most people realize. At first glance, coverage has been on the rise, with the number of children receiving all doses of diphtheria-tetanus-pertussis–containing (DTP) vaccines (the traditional yardstick of immunization coverage) increasing from 73% to 83% in the last decade. However, a look at the number of children receiving all 11 vaccines recommended by the World Health Organization for universal usage—diphtheria, pertussis, tetanus, polio, Haemophilus influenzae type b, hepatitis B, measles, rubella, BCG (against tuberculosis), pneumococcal, and rotavirus—reveals a very different picture, with just 5% of the world’s children fully immunized. It’s little wonder that 1.5 million children still die from vaccine-preventable diseases every year.

Increasing the number of children who are fully immunized could make a huge impact on this figure, not least because some of these new, powerful vaccines target major killers. Rotavirus and pneumococcal vaccines, for example, protect against some of the main causes of diarrhea and pneumonia, the two biggest causes of death among children under age five.

Innovative efforts by Gavi, the Vaccine Alliance, have helped accelerate access to new and powerful vaccines. This year, we will support the introduction of one new vaccine in a Gavi-eligible country every week on average. However, introducing these vaccines is just the first step. The bigger challenge is ensuring they reach every single child, including the most remote and marginalized. This will require new tools such as digital and geographical information systems so we know where those children are and who is being missed, innovative supply chain equipment and practices so we can get vaccines everywhere they are needed, and better human resource management. Together, these can enable countries to leapfrog into much higher-performing health systems and dramatically increase access to vaccines as well as other vital health interventions.

Newer vaccines have also moved us from prevention of traditional infectious diseases to infectious causes of chronic diseases, such as cancer. Today we already have vaccines to protect against two common cancers: liver cancer (hepatitis B) and cervical cancer (human papillomavirus), and there are others in the pipeline. Given that today more than 30% of cancers in Africa have known infectious antecedents, as opposed to less than 10% in industrialized countries, this kind of innovation will prove vital.

In the long term, the trend of innovation in R&D can also lead to vaccines for many more pathogens, such as HIV, hepatitis C, malaria, and tuberculosis, all of which have thus far challenged traditional vaccinology. In the meantime, if we continue to invest in immunization innovation, by 2020 we should be able to dramatically increase the number of children who are fully immunized and come significantly closer to reaching every child.