A mother in Tanzania cradles her week-old son as the nation’s First Lady Salma Kikwete drips a rotavirus vaccine into the tiny “O” of his mouth, helping to protect the infant against severe, and often deadly, rotavirus diarrhea.

It took a lot to arrive at this moment: community education for the mother so she knew to make the difficult journey with her baby for vaccination, the training of hundreds of health workers, new registries and immunization cards, an upgraded cold chain to store the vaccines at the right temperature, a commitment to sustainable vaccine funding—and the decision by the Tanzanian government to introduce rotavirus vaccines into the country’s immunization program.

Just weeks ago, Tanzania became the 8th country in Africa to make rotavirus vaccination part of its childhood immunization program. With the competing priorities of running a nation and keeping its citizens healthy, how did rotavirus vaccines rise to the top for Tanzania’s leaders? In part, it was because of the compelling evidence and the efforts of scientists and medical practitioners who brought it to light.

Diarrhea is one of the world’s leading killers of children, and rotavirus is the most common cause of severe, deadly diarrhea. For every child that dies, many more endure unnecessary suffering and often require hospitalization.

As doctors, we’ve witnessed the anguish of parents who brought in children too late, already limp in their arms, suffering from the life-threatening dehydration caused by rotavirus. As scientists, we know that rotavirus is extremely contagious and nearly every child is vulnerable. Improvements in hygiene, sanitation and drinking water are critical components to preventing diarrhea but do not adequately prevent the spread of rotavirus.

Vaccination offers the best hope for protecting children from rotavirus and is an essential part of comprehensive diarrhea control.

Because ninety-five percent of rotavirus deaths occur in low-income countries, seven years ago, researchers set out to conduct clinical trials in impoverished settings across Africa and Asia to better understand how rotavirus vaccines would work among the infants and children who needed them most urgently. They found that rotavirus vaccines reduced the risk of severe rotavirus in these countries by more than half during the first year of life, when children are at greatest risk. And in June 2009, based in part on the findings from these studies, the World Health Organization recommended that rotavirus vaccines be included in all national immunization programs.

The evidence is compelling and the data are powerful. Countries that have introduced these vaccines have seen major reductions in hospitalizations and deaths from diarrhea. Over the next few decades, millions of unnecessary illnesses and deaths can be prevented by accelerating access to these vaccines. Despite this, today, only 42 countries worldwide have introduced rotavirus vaccines into their national immunization programs.

Advocacy is needed, and scientists and medical practitioners are uniquely suited to step up to the challenge. We conducted the research, and as doctors, we have treated the children in need. We possess firsthand knowledge of the impact of these vaccines, and it is our responsibility to share this information with policymakers so they are fully informed to make decisions that best protect the lives of their youngest citizens.

We must commit to redoubling our efforts to ensure the evidence generated through surveillance, clinical trials and impact studies continues to inform how health programs develop so that, no matter where they are born, every child has access to health interventions that work, like rotavirus vaccines. Millions of children have already benefited from these vaccines—millions more continue to depend on us.

Dr. Mathuram Santosham and Dr. Ciro de Quadros co-chair the Rotavirus Organization of Technical Allies (ROTA) Council, an organization of technical experts working to save children’s lives and improve health by providing the evidence policymakers need to accelerate the introduction of rotavirus vaccines.

 Learn more about how rotavirus vaccines can improve health and save lives at www.ROTACouncil.org.