I noted in my post about Pakistan that a shortage of clean water for millions of flood victims may lead to outbreaks of diarrheal diseases. It’s worth getting into the issue of how unclean water causes these diseases. Basically, the problem is water contaminated by human feces.

In Clinical Microbiology Reviews, Qadri et al list the major agents behind the estimated annual toll of 1.5 million deaths from diarrheal disease: Enterotoxigenic Escherichia coli, or ETEC (the group of E. coli that produce toxins that cause diarrhea); Vibrio cholerae; Shigella; and rotavirus. These three bacteria and one virus are spread via the feces of infected people (though not exclusively by that route), and in countries without adequate sanitation the spread is often by contamination of water supplies with feces.

Fecal pathogens don’t always find their next victims via water, of course. The “F Diagram” (this one is from the World Bank’s website) lists four ways diseases can be transmitted from feces: fluids, fingers, flies, fields/floors. Hygiene is the only way to stop transmission via fingers, but adequate sanitation can block the other routes.

What constitutes adequate sanitation? The World Health Organization uses the term “improved sanitation facilities,” which it defines as “adequate excreta disposal facilities (private or shared, but not public) that can effectively prevent human, animal, and insect contact with excreta.” Toilets connected to public sewer systems or septic systems qualify, as do many latrines. Latrines that use an open pit or require manual removal of excreta don’t qualify, nor do public latrines, because they are seldom maintained adequately and may not be accessible by all populations at all times.

The ultimate goal is for everyone in the world to use improved sanitation facilities, but in the meantime the Millennium Development Goal target is to halve the number of proportion of the population without sustainable access to basic sanitation. In 1990, only 54% of the world’s population used improved sanitation facilities; the MDG target aims to bring that number up to 77% by 2015. In 2008, however, that number had only reached 61%. The increase represents 1.3 billion people who gained access to improved sanitation facilities between 1990 and 2008, but the WHO/UNICEF Joint Monitoring Programme for Water Supply and Sanitation estimates that we’ll still end up missing the target by one billion people.

One of the difficult things about the global effort to improve sanitation is that it’s not as simple as just building more toilets and latrines. The good news is that we seem to be figuring out more about what works.

When people don’t have improved sanitation facilities, they often practice open defecation, which basically entails walking to a secluded spot and squatting. In urban slums, “flying toilets” are not uncommon – people defecate into plastic bags and toss them away. And as strange as it might seem for those of us who grew up using toilets, they don’t necessarily see these habits as problematic.

In previous decades, NGOs and governments often focused on building new latrines or toilets for people, but far too often the facilities weren’t used. In some cases, people turned toilet sheds into storage facilities and continued practicing open defecation. Having learned from less-than-successful experiences, aid organizations are now supporting “demand-driven” water and sanitation services, in which governments and donors focus on creating demand rather than supplying hardware.

Driving Community Demand for Sanitation
One of the most intriguing approaches to creating demand for improved sanitation facilities is the community-led total sanitation movement, which was created in Bangladesh in 1999 by consultant Kamal Kar with the Village Education Resource Centre and WaterAid. A working paper by Kar and Katherine Pasteur describes the steps of the CLTS approach.

A team of facilitiators goes to a village, and instead of lecturing residents about the perils of open defecation, they recruit a group of community members to take them on a transect walk around the village to visit the different types of latrines used. The walks also pass by places where people often practice open defecation – and it turns out that in the presence of “dignified outsiders,” the community members are embarrassed to be visiting these dirty spots. Facilitators ask questions about who defecates in these spots and what happens during seasons of high incidence of diarrhea. The transect walks generally result in community members planning a meeting, at which facilitators help them calculate the community’s annual feces production and map routes of fecal contamination. These exercises generate disgust and a desire to address the problem, and facilitators help community members create a plan for ending open defecation. Kar offers a more succinct summary of this process in this video:

When they realize they’re ingesting each other’s shit, and nobody wants to stay in that condition, they don’t wait for any outside help or any subsidy to get out of the situation. They immediately jump into action.

The next step is usually the formation of a committee and a decision about how they’ll end open defecation. Construction of household latrines or other facilities is usually the focus, with the community members deciding which model(s) will work best in their village. Often, the committee members will first construct their own latrines, and then go about convincing their neighbors to do the same. Children can enjoy the chance to walk through the village chanting sanitation slogans, embarrassing people in the act of open defecation, and planting flags in spots where people have defecated.

By helping communities empower themselves to address their sanitation problems, CLTS lays the groundwork for a sustainable end to open defecation. UNICEF states that CLTS “has been well tested in Asia, and has enabled countries like Bangladesh to get back on track with their MDG goals in sanitation without the support of subsidies.” The organization notes that CLTS has also been successfully introduced in Ethiopia, Kenya, Sierra Leone, Nigeria, and Ghana.

Although progress on sanitation isn’t as quick as we’d like it to be, it’s cheering to see that we’re figuring out how to achieve sustainable sanitation gains. The more people we have habitually using toilets and latrines, the happier the world will be.