Other public health issues, such as malaria, are better-known causes, Winch notes, even though they might not be responsible for as many child deaths. "Malaria has a clearer image in people's minds," he adds. There are mosquitoes, nets and it is "something that appears you could make progress on." Diarrhea, aside from a less comfortable conversation topic, often stems from unclean water and poor sanitation services, infrastructural issues that appear more difficult—and more expensive—to tackle, he explains. "Policymakers don't see diarrhea as a big problem," Winch says. "There's a lot more funding out there for AIDS, malaria and tuberculosis, and funding gets people's attention."
Zinc may give agencies and public health groups a new, tenable solution to the widespread problem. "What drives the international effort for scaling up zinc is its preventive role," Larson says. Widespread adoption could avert some 400,000 deaths of children under five each year, according to a 2003 study in The Lancet.
Figuring out just how to spread the word about zinc will require more work and better understanding of the communities that would benefit. Studying how—and why—people change their behavior has helped other public health campaigns, including malaria, with the wider use of bed nets. Larson notes that, after advertising, it is important to promote the image of individuals making the decision for themselves. It also comes down to involving the stakeholders, such as mid-level government officials and physician groups, who ultimately play a large role in a program's success.
For all of the lessons learned in Bangladesh, Larson stresses, "one size doesn't fit all. There's no template here." For zinc—or any other public health program like this—to succeed, it is crucial to do the legwork. His group laid the foundation for the project by first talking to the target populations: citizens—rich and poor—who had kids that suffered from diarrhea. Before assembling the project's components, Larson's team asked simple questions, such as how much people paid for other treatments and why they might use them. The answers helped the researchers to set appropriate prices, decide how to position zinc as a treatment and, in the end, aided in disseminating a new weapon against a condition that causes some 19 percent of all under-five childhood deaths worldwide.