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646 Very Personal Questions

Can asking about people's toilet habits-and tailoring hygiene information to their answers-help save the lives of African children? Civil engineering professor Jenna Davis is working with Tanzanians to find out.

Robert L. Strauss

LITER MAIDS: In the Mburahati neighborhood of Dar es Salaam, girls gather water from a borehole distribution point.

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By Robert L. Strauss

In a hotel conference room five floors above Dar es Salaam, Jenna Davis is prepping a team of 22 Tanzanians who soon will begin surveying hundreds of local families about their habits regarding water, sanitation and hygiene. Two-ply or one-ply is not one of the 646 questions they will be asking.

Down in the streets of “Dar,” very few of its 2.5 million inhabitants have ever faced the dazzling array of toilet paper and bottled water that lines the aisles of American supermarkets. More commonly, for the first necessity, they use varying combinations of coarse toilet paper, water, sand, ashes, old newspapers, leaves or corn cobs. The choices for drinking water include Kilimanjaro, a locally popular brand, but more commonly involve communal taps or jerry cans filled from large tanker trucks from Whoknowswhere. Hundreds of thousands rely on brackish, stagnant water drawn from shallow wells that often look and smell like untended fish tanks. A foreigner who drinks that water is virtually guaranteed a case of raging diarrhea—if not something much, much worse.

At least 2 billion of the world's population lack adequate supplies of water and proper facilities for the safe disposal of human waste. These deficiencies contribute to the deaths each year of perhaps as many as 2 million children under 5 years of age. Billions of working hours are lost when adults care for sick children or fall ill themselves.

For Davis, an assistant professor of civil and environmental engineering and a fellow at Stanford's Woods Institute for the Environment, a great deal of the problem revolves around what she calls the “five Fs”—flies, food, fingers, feces and fields, with fields representing a genteel way of referring to people who defecate in the open because they have no other place to go.

These are not, Davis says, subjects that get her a lot of after-dinner speaking engagements. “Shit isn't sexy,” she says of the path her career has taken. As a young environmental researcher, she “got lonely looking at plants and bugs and no people. So I started thinking about a field that involved people. The places I ended up, all people wanted to talk about was diarrhea.”

Dar es Salaam, Tanzania's commercial capital and largest city, is a good proxy for much of urban, sub-Saharan Africa. People are poor—with nearly 90 percent of Tanzanians getting by on less than $2 a day. Only the old, colonial core of Dar is connected to a sewer system. Outside that core, 90 percent or more of the city's population uses on-site sanitation, meaning, Davis explains, that the household's excrement is “staying under the house.”

For many Tanzanians, the restroom is some version of a “squatter”—a small hole with two defined spaces to indicate where the user's feet should be positioned. At its simplest, a squatter might be a hole in the ground with a couple of pieces of wood on either side to elevate the feet above ground zero. Top-of-the-line squatters have a water trap that seals the smell beneath the water as in a flush toilet. Flushing might entail the opening of a spigot or the ladling of water from a bucket to swish the waste away.

Outdoor squatters sometimes look like the cartoon stereotype of an outhouse, right down to a crescent moon cut into the door. In Tanzania, particularly in rural areas, “passport” latrines are common. Those are roofless ones with walls so low that the person inside is visible to everyone passing by, but from the shoulders up—as though he or she were squatting while posing for a passport photo. And then there are composting latrines, VIP (“ventilated, improved pit”) latrines, “long drops,” “short drops” and many other permutations.

Because Dar es Salaam is coastal, it has a high water table. Human waste that goes into one type of hole in the ground or another still winds up not all that far from the surface. People without access to toilets or latrines sometimes use plastic bags that get tossed into the street. Sometimes the bag is dispensed with altogether. “Particularly during the rainy season, everything washes into everything else,” Davis says. “People come into contact with fecally contaminated water everywhere.” It's not surprising that 39 percent of hospital admissions in Dar es Salaam can be attributed to hygiene-related issues.

For Davis and her collaborators, Alexandria Boehm, an assistant professor of civil and environmental engineering, and Professor Gary Schoolnik from the School of Medicine, success will mean figuring out what information households need to make more effective decisions about hygiene.

According to Davis, much of the past research on hygiene in the developing world has looked at only one or two pieces of the puzzle at a time—such as the availability of clean water, but not facilities for the disposal of waste. Or the existence of a toilet, but not how many people use it. Or the frequency of hand washing, but not a household's ability to have soap always available. Or the number of children in a household, but not what hygiene measures their caregivers enforce.

Davis thinks the key to the puzzle is figuring out “what is it that gets people to invest—their time, money and mental energy—to improve their hygiene situation?” She thinks one of the answers might be giving people information precisely tailored to their particular circumstances.

“The huge challenge in our field is behavior change,” says Amy Pickering, a second-year PhD candidate at Stanford and a manager on the Tanzania project. “No one has discovered a surefire way to motivate behavior change. It would make me really happy to find out that giving people personalized information about their situation works.”

In Dar es Salaam, having the simplest of pit latrines dug will cost about 100,000 Tanzanian shillings, about $100 at current exchange rates. Getting one's house connected to the local water system can cost three times that amount, a significant outlay in a country where the estimated average annual income is about $750. And even if the house is connected, that's no guarantee there will always be water in the tap. As in many African cities, the supply of electric power in Dar is sketchy; often there is no juice to run the engines that pump the water from deep wells.

“We're not breaking the cycle [of hygiene-related illness],” Davis says, “because the infrastructure is lousy.” In the developed world, the cycle was broken long ago because governments invested in extensive clean water and sewerage systems that could be extended regularly, albeit at great cost. In developing countries, such systems were typically put in place by the colonial powers only in elite neighborhoods and commercial centers. Water and sanitation infrastructures have been playing a losing game of catch-up with rapidly growing populations ever since.

The view from the hotel conference room five stories above Dar es Salaam makes clear how the modernization needs of hundreds of thousands of Tanzanians compete for their sparse disposable income. Not many water or sanitation improvements are in sight. But in every direction cell-phone towers jut up above the city the way oil derricks once outlined the skyline of boomtowns in Texas.

Davis and her team recognize that “wat-san” is a low priority for many people in Tanzania and is likely to remain so. This makes sussing out what information might convince people to change their behaviors and priorities critical. Before the survey teams go into the field, Davis will have spent two weeks refining the questionnaire with them.

Each question is checked to make sure it has been translated clearly from English to Swahili and transferred correctly to the handheld digital devices the Tanzanian enumerators will use to record responses. Getting the translation right is not always easy. “Household” is the key group Davis wishes to study, but determining just what a “household” is in the Tanzanian context leads to a lengthy discussion. In one location, the researchers found a house that had 12 family groups living in it, with 60 people using one toilet. The group must decide whether this constitutes a single household or a dozen.

Though the work is tedious, Davis manages to infuse it with a lighthearted touch. As a way of demonstrating what the Tanzanian team members should not do, she pantomimes searching a household for waste, flies and feces. She looks behind the curtains. She peers under the conference room tables. She pretends to enter a disgusting outhouse and reels back, holding her nose. The enumerators, some of whom have expertise in social work or environmental health, break into laughter. They know that an overzealous researcher can easily alienate a respondent and are happy to see that Davis is not an ivory tower researcher, but someone who has spent time in the trenches (and latrines).

The project, sponsored by a $210,070 grant from Stanford's Presidential Fund for Innovation in International Studies and a $137,026 grant from the Woods Institute for the Environment, is unusually ambitious and complicated. In addition to the vast survey information, the Tanzanian enumerators will, on four different occasions, collect water samples from each of 330 households. Samples, too, will be gathered from the hands of each household's children and their caregivers.

To get those samples, the enumerators will have people immerse their hands in plastic bags filled with clean water. Davis and her assistants explain that the immersed hand must be massaged for a full 15 seconds to make sure that germs the person might be carrying get washed into the water. Air must be squeezed out of the bags in a prescribed manner before they are tied off.

An unexpected societal subtlety crops up. In many African cultures, a man tickling the inside of a woman's hand signals that he has more on his mind than just the strength of her grip. Some of the enumerators express concern that Tanzanian men won't look favorably on another man rubbing his wife's, daughter's or girlfriend's hand, even if it is for the advancement of science. The Tanzanians confer and come up with a solution. Each two-person team will consist of a man and a woman, and only female enumerators will massage any female hands.

The thousands of samples will be taken, cultured and analyzed in a laboratory that doubles as one of the Stanford researchers' communal apartments in Dar. Samples also will be sent back to Stanford for genetic analysis that will help identify the origin of any possible pathogens.

To better understand how people respond to different levels of information, the 330 Tanzanian households will be divided into four different cohorts. By the end of the research period, all four groups will have received the same information. During the study, however, they will get differing levels of feedback. The researchers hope that by comparing the incidence of diarrheal disease among the four different groups they will have a better idea whether highly specific information is more effective at getting people to alter their behavior than general-awareness messages that go out to the public as a matter of course.

In more earthy terms, what Davis wants to know is whether a family with a high incidence of diarrheal disease will change its behavior after learning that the sources of its problems might include the uncovered outdoor latrine that it shares with dozens of others, or its failure to protect food from feces-carrying flies, or any of a number of highly specific disease vectors. Will it have less disease than a comparable family who heard only admonitions such as “Always boil your water and wash your hands”? The Dar es Salaam Water and Sewerage Authority (DAWASA), Stanford's partner in this project, hopes that the research will clarify why, despite the drilling of dozens of boreholes that provide water to more than 150,000 local residents, the incidence of hygiene-related morbidity has barely budged.

Neli Msuya, DAWASA's community liaison manager, thinks part of the reason is that not much is really known about people's habits. “We have never been strong in hygiene and sanitation,” Msuya says. “They have been considered personal affairs. We don't talk about them. Just like AIDS.” During the four years she has worked at DAWASA, Msuya has noted that everyone was always talking about “water, water, water.” But when morbidity failed to drop as more and better water became available under the Community Water Supply and Sanitation Program, Msuya and other community mobilizers realized that the provision of water alone would not solve the larger problem.

The researchers and public health experts are also confounded by the fact that many Africans may consciously and rationally evaluate hygiene interventions that would improve their health but decide not to take them.

“All people understand,” says Stephen Kiberiti, a board member of HERO, the Health and Environmental Rescue Organization, a Tanzanian nongovernmental organization that is helping coordinate the fieldwork. “But then the issue is the use of resources and the issue of ownership. Most people in Dar, the houses are not theirs. Most are renting a room.” In classical economic terms, it's a question of the commons. Someone with no ownership stake is unlikely to invest in a communal solution. If the neighbors keep defecating in an adjacent field, the health benefits to the person who builds a latrine for his or her own family may turn out to be zero.

Tradition and cultural patterns also influence decision making in a significant way that is often hidden from foreigners or difficult for them to comprehend. Agnes Lwitiko, one of the Tanzanian enumerators, notes that “when you ask people about the importance of [water] treatment, they say they know, but” they also know that “it's expensive and my grandfather and grandmother didn't do it that way.”

Davis observes that in Tanzania, “decisions about expenditures tend to be dominated by men. Females have responsibility for health care.” The Tanzanian enumerators agree that if women were fully in charge of how the household shillings were spent, hygiene would get greater attention.

But some remain unconvinced. Stephen Kiberiti laments, “People will say, 'We never used a toilet; how can we use it now?' Even in a new house, the toilet will be the last priority.”

Days before the actual fieldwork is supposed to begin, the entire team has come to the Ubungo district of Dar es Salaam to perform several dry runs. Dirt paths spider-web their way between the ramshackle homes of squatters and the walled, satellite-dish-equipped compounds of the middle class. Nearby, a huge thermoelectric power plant rumbles constantly. Abandoned, broken spigots testify to the failure of a previous attempt at extending the infrastructure. Garbage carpets a steep hillside that leads down to a small enclave of houses.

At the bottom of the hill, a crowd of children gathers immediately to see what one of the two-person survey teams is up to. In much of the developing world, no matter how many boreholes are drilled or latrines are dug, children will still be children. They'll play outside, where they will be exposed to human and animal waste, uncollected garbage, litter, clogged or nonexistent drainage, and other children whose fingernails also may harbor the eggs of parasites, noxious bacteria and other assorted cooties that Westerners hardly know exist.

Davis's study, like many others, has a strong focus on young children because, like canaries in coal mines, children under age 5 are the bellwethers of public health. The bout of diarrhea and dehydration that temporarily incapacitates an adult can easily kill a child. If the problem can be solved for the more vulnerable child, it's likely to be solved for the adult. The reverse is not necessarily true.

The children's interest in the enumerators waxes and wanes as pedestrians walk past, as dogs bark and butterflies flit through the 90-degree heat. What these kids know about public hygiene is that at the earliest age possible, they should go outside the house to do their business. Foreigners visiting Africa for the first time are sometimes taken aback at seeing a diaperless baby step—or crawl—over the threshold of a house and defecate. When a stray dog or pig then comes by and eats the waste, the foreigner's chagrin may be multiplied. (It may take that foreigner several rethinks before recognizing that this African toilet training may not be any worse than creating new landfills for the disposal of loaded diapers that won't biodegrade for centuries.)

Davis understands that solving the problems of water and sanitation in developing countries represents a two-steps-forward, one-and-a-half-steps-back kind of calculus. She recalls that the 1980s were supposed to be the decade of “Water and Sanitation for All.” “I think we're realizing how daunting it is,” she says. “It's important to recognize that the U.S. didn't have a high proportion of its wastewater being treated until the 1970s. In places like Dar, you don't have the tax revenue or the ability to float bonds. So what you have is international aid.”

Until recent years, about $15 billion was spent annually on water and sanitation, most of that going to water-supply improvements. Now the United Nations' Millennium Development Goals call for cutting in half the proportion of the world's population without sustainable access to safe drinking water and basic sanitation by 2015. For that to happen, the amount of money that needs to be invested annually would have to increase by as much as $30 billion a year.

The money isn't there. Davis believes individual households must be supplied with information so that they can better grapple with their own sanitation problems.

According to the U.N.'s Human Development Report 2007/2008, in Tanzania 47 percent of the population is already using improved sanitation and 62 percent has access to improved water sources. Walking around Ubungu and other untouristed neighborhoods of Dar es Salaam, those figures are hard to believe—or at least make one question what “improved” really means. As Neli Msuya notes, “Everybody has a toilet but 83 percent are in bad shape.”

Even if the money to bring safe sanitation to all of Dar es Salaam were available today, construction could take decades. Simple logistics in the city can consume days. Davis's project is a year behind schedule because, in 2007, Davis didn't get a timely okay from the Tanzanian government—despite submitting the proposal seven months ahead of schedule. For this year's fieldwork, Davis made sure the 10 Stanford researchers took critical supplies along as checked baggage, only to have the bags wind up in Dubai, where they remained for several weeks while various security agencies rummaged through them. In Dar es Salaam, $55,000 of lab supplies were blocked at the port, where Tanzanian officials demanded more than $24,000 in import duties before finally reducing the bill to a tenth of that. Finding a liter of pure ethanol needed to sterilize some of the test equipment engaged several of Davis's students in a multiple-day treasure hunt throughout Dar.

Despite the challenges, Davis's never-say-die, always-smiling attitude seems to rub off on all those around her. Stanford junior Annalise Blum says, “I never had a particular interest in studying sewerage or people's waste, but Jenna is very persuasive at getting students to realize how important it is—even if it's not the most appealing of subjects.” Blum says that everyone told her if she wanted to be helpful she should become a doctor. She jokes that that wasn't an option because she can't “stand the sight of blood. So now I'm studying shit.” In the academic community, wits refer to this field of study as “turd herding.” At Stanford, Davis and her students are sometimes called the “Poop Group.”

Davis takes it in stride. “I'm basically optimistic,” she says. “Everybody is interested in improving the health of their families, improving the economic standing of their households. And so tapping into innovations and ideas that these communities have always yields interesting, effective and actionable ideas and strategies, which are often remarkably innovative and clever, particularly given the lack of resources they have.”

Davis says many development projects that didn't work out often failed because “we [outside researchers] come in with a preformed notion of what might work. But critically important is getting in the minds of the people. In this study, we're not going to show up with a water filter or a bottle of chlorine. The idea is to spark their imagination. We're going to talk about lots and lots of options, but then it's up to them. We're going to let them draw on their own motivation and resources to solve their problems.”

ROBERT L. STRAUSS, MA '84, MBA '84, was the country director for the Peace Corps in Cameroon from 2002 until 2007. A writer and consultant, he now lives in Madagascar.

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