SEATTLE - Vaccines work wonders. They prevent disease from striking, which is better than treating it after the fact. They are also relatively cheap and easy to deliver. Yet millions of children do not get them. This has always been stunning to me. When we started the Gates Foundation 15 years ago, we assumed that all of the obvious steps were already being taken, and that we would have to go after the expensive or unproven solutions. In fact, delivering basic vaccines is still one of our top priorities.As I look ahead to 2014, I am more optimistic than ever about the progress that we can make using the power of vaccines to give all children – wherever they live – a healthy start to life. We have new resources from generous donors worldwide. We are developing new and better vaccines to protect kids from deadly diseases. And we are finding innovative ways to deliver them, especially in hard-to-reach areas.One of the most exciting – and often overlooked – developments in the global push to give all children access to immunization is the growing role of emerging-country vaccine suppliers. Countries like Brazil, China, and India have faced many health and development challenges of their own, and they have made tremendous progress. Now they are using their experience and technical capacity to help other countries make similar progress.You have probably never heard of many of the pharmaceutical companies – Serum Institute of India, Bharat Biotech, Biological E, China National Biotec Group, and Bio-Manguinhos, to name just a few – that have become some of our most valuable partners in global health. By harnessing the same innovative spirit that transformed emerging markets into manufacturing hubs for everything from cars to computers, these companies have become leaders in supplying the world with high quality, low-cost vaccines.The increased competition and new manufacturing approaches created by these companies have made it possible to protect a child against eight major diseases – including tetanus, whooping cough, polio, and tuberculosis – for less than $30. Serum Institute produces a higher volume of vaccines than any other company in the world and has played a key role in cutting costs and boosting volumes.Thanks to the efforts of these suppliers and their close partnerships with the GAVI Alliance, multinational vaccine manufacturers, and international donors, more than 100 million children a year – more than ever before – are being immunized. As more suppliers enter the market and stimulate competition with innovative manufacturing techniques, prices will likely drop even further.Consider the progress that has been made with the lifesaving pentavalent vaccine, which protects a child against diphtheria, tetanus, whooping cough, hepatitis B, and haemophilus influenza type b (Hib) – all in one dose. When the GAVI Alliance first introduced it in 2001, there was one supplier and the cost was $3.50 per dose. As demand for the vaccine grew, GAVI encouraged other suppliers to enter the market, and the price tumbled. Now there are five suppliers, and Biological E, an Indian pharmaceutical company, announced earlier this year that it would offer the vaccine for just $1.19 per dose.We have also seen major emerging countries invest in biomedical technology to supply developing countries with new vaccines. India’s Department of Biotechnology and Bharat Biotech announced plans this year to release a new vaccine against rotavirus – which kills hundreds of thousands of children – for $1 per dose, significantly cheaper than existing vaccines. Likewise, a Chinese biotech company won approval in October from the World Health Organization to bring to market an improved vaccine protecting children against Japanese encephalitis. The same month, Brazil’s top biomedical research and development center, Bio-Manguinhos, in partnership with the Gates Foundation, announced plans to produce a combined measles and rubella vaccine.When I first got involved in global health more than 15 years ago, these kinds of announcements were rare. The vaccine field was dominated by a handful of multinational pharmaceutical companies in rich countries, and the entire sector suffered from a lack of competition. Today, emerging-country manufacturers produce about 50% of vaccines purchased by United Nations agencies for use in the developing world, up from less than 10% in 1997.The contributions of emerging-country vaccine producers often complement the work of their counterparts in developed countries. In fact, some of the most innovative ideas have come from their combined efforts. The Gates Foundation supported a major partnership between the Serum Institute of India and SynCo Bio Partners, a Dutch vaccine producer, to produce a low-cost vaccine to protect more than 450 million people in Africa from meningitis. This year, Biological E announced two major partnerships with multinational vaccine manufacturers. A joint partnership with GlaxoSmithKline will produce a six-in-one vaccine protecting children against polio and other infectious diseases; another, with Novartis, will produce two vaccines that will protect millions of people in the developing world from typhoid and paratyphoid fevers.Despite all of this progress, more must be done to target the 22 million children, mainly in the poorest countries, who do not have access to lifesaving vaccines. Without protection against deadly diseases like measles, pneumonia, and rotavirus, many of these children are being denied a chance to grow up healthy, attend school, and lead productive lives. Their countries lose, too. Disease robs a poor country of the energy and talents of its people, raises treatment costs, and stymies economic growth.We live in a world where we have the power to correct this injustice. We have the knowhow to produce effective vaccines, make them affordable, and deliver them to the children who need them. Emerging-country vaccine suppliers are a critical part of this process. Thanks to their contributions, we are moving closer to the day when all children can have a healthy start to life.Bill Gates is Co-Chair of the Bill & Melinda Gates Foundation Copyright: Project Syndicate