The current generation of vaccines against rotavirus, the leading cause of diarrheal disease in children under five years old, was introduced just a decade ago. In the intervening years, 81 countries have implemented rotavirus vaccination to prevent diarrheal disease.

Since the administration of the first vaccine, immunization policy has evolved to better meet public health needs around the world. This evolution is most apparent when considering immunization policy in developing countries over the past 50 years.

It takes more than a vaccine to make a successful immunization program. This World Immunization Week, we are taking a look at some of the factors that contribute to effective immunization programs.

Despite the fact that safe, effective vaccines exist to prevent rotavirus, the disease continues to kill nearly half a million children each year and hospitalizes millions more.