Since the mid-19th century, the health benefits of handwashing with soap have been common knowledge in many countries. Despite this, poor hygiene is a major contributor to diarrhea and acute respiratory infection—two of the most common killers of children in low- and middle-income countries.

A study conducted in Peru in 2000 found that an average of 15 percent of children under five had experienced diarrhea within the previous two weeks. source And as of 2004, a mere 14 percent of mothers washed their hands with soap after using the toilet, and only 6 percent of mothers did so before cooking. source But improving handwashing habits is hard, even when knowledge about the benefits is widespread and soap and water are readily available. source

The Peruvian government began a handwashing initiative (HWI) in 2003 as a multisectoral effort to increase handwashing among mothers and young children. The HWI, which was a collaboration with the Global Public-Private Partnership for Handwashing with Soap, used public education and media messaging to spread the word in 14 of the country’s 25 regions. The program got a major boost in 2007 when the World Bank’s Water and Sanitation Program and Bill & Melinda Gates Foundation added their resources and know-how through the Global Scaling Up Handwashing Project, an evidence-based program to improve handwashing behavior in real-world settings.

Short-term, small-scale projects have shown that handwashing with soap can reduce childhood diarrhea; the problem is in scaling up those programs.

The HWI strategy was to surround the target group—mothers, caregivers, and children under 12—with consistent messages using mass media, direct consumer contact, and community- and school-based activities. The initiative reached its target audience, increased their knowledge, and improved self-reported handwashing behavior. However, evidence from an impact evaluation found that the combination of efforts were neither potent nor consistent enough to significantly improve child health.source The evidence has suggested that aspects of delivery, commitment, and capacity limited the impact. Peru’s rapid economic growth and improved living conditions over the past decade may also have muted the initiative’s impact.

Despite its disappointing results, the Global Scaling Up Handwashing Project provided the first-ever opportunity to study the impact of a large-scale, real-world handwashing program on a range of health outcomes. The experience yields important lessons on sanitation and hygiene promotion efforts for Peru and beyond.