Publications Directory

Publications Directory

Solar inactivation of four Salmonella serovars in fresh and marine waters
Ali Boehm, Cherrie Soetjipto, Dan Wang

This study sought to document the photo-inactivation of environmental isolates of Salmonella in filter-sterilized natural seawater and freshwater and to test the hypothesis that diverse Salmonella serovars decay at similar rates both within and between water matrices. The inactivation of Salmonella enterica Typhimurium LT2, Typhimurium ST19, Heidelberg, and Mbandaka was examined in sunlit and dark microcosms. The results document intra-species variation in photo-inactivation, likely owing to differences in intracellular concentrations of photo-sensitizing molecules or molecules that quench reactive species.

Water, Sanitation and Health Other Sunday, January 1, 2012 Visit Website
Comparison of enterovirus and adenovirus concentration and enumeration methods in seawater from Southern California, USA and Baja Malibu, Mexico
Lauren M. Sassoubre, David C. Love, Andrea I. Silverman, Kara L. Nelson, Ali Boehm

This study examines enterovirus and adenovirus concentrations in coastal water samples collected from four beaches impacted by microbial pollution: (1) Malibu Lagoon, Malibu; (2) Tijuana River, Imperial Beach; (3) Baja Malibu, Baja California; and (4) Punta Bandera, Baja California. The detection of viruses by MF and (RT)QPCR was positively correlated with the presence of infectious viruses. Further research is needed to determine if detection of viruses by rapid methods such as (RT)QPCR can be a useful water quality monitoring tool to assess health risks in recreational waters.

Water, Sanitation and Health North America Sunday, January 1, 2012 Visit Website
Smallholder irrigation as a poverty alleviation tool in sub-Saharan Africa
Jennifer A. Burney, Rosamond Naylor

Burney and Naylor evaluate three important sub-components of irrigation technology--access, distribution, and use-- and the ways in which the design of the technology can either bridge, or succumb to, institutional gaps as they apply to a solar-powered drip irrigation project in rural, northern Benin. The combined evidence highlights the technical and institutional requirements for project success and points to two important areas of research in the scale-up of any small-scale irrigation strategy: the risk behavior of water users, and the evolution of institutions that either support or obstruct project replication over space and time.

WASH and Development Sub-Saharan Africa Sunday, January 1, 2012 Visit Website
Climate trends and global crop production since 1980
David Lobell, Wolfram Schlenker, Justin Costa-Roberts

A study of how trends in climate have affected crop productivity in different regions, and the relevant importance of temperature and rainfall.

Sustainable Service Models, WASH and Development Other Friday, July 29, 2011 Visit Website
Understanding Household Behavioral Risk Factors for Diarrheal Disease in Dar es Salaam: A Photovoice Community Assessment
Natalie Badowski, Cynthia M. Castro, Maggie Montgomery, Amy Pickering, Simon Mamuya, Jenna Davis

This study utilized a qualitative, cross-sectional, modified Photovoice method to capture daily activities of Dar es Salaam mothers. The photographs and interviews revealed insufficient hand washing procedures, unsafe disposal of wastewater, uncovered household drinking water containers, a lack of water treatment prior to consumption, and inappropriate toilets for use by small children. The results draw attention to the real economic and behavioral challenges faced in reducing the spread of disease.

Water, Sanitation and Health Sub-Saharan Africa Wednesday, July 27, 2011 Visit Website
Swimmer risk of gastrointestinal illness from exposure to tropical coastal waters contaminated with terrestrial runoff
Emily J. Viau, Debbie Lee, Ali Boehm

This study used molecular methods to measure concentrations of four enteric viruses (adenovirus, enterovirus, norovirus GI, and norovirus GII) and fecal source tracking markers (human, ruminant, and pig Bacteroidales) in land-based runoff from 22 tropical streams on O’ahu, Hawai’i. Virus concentrations and culturable Salmonella and Campylobacter were used as inputs to a quantitative microbial risk assessment model to estimate the risk of acquiring gastrointestinal illness from swimming in tropical marine waters adjacent to discharging streams. The results of the study suggest land-based runoff in the tropics as a potential source of GI illness risk, with pathogens coming from both human and nonhuman nonpoint sources including septic tanks.

Water, Sanitation and Health North America Friday, July 22, 2011 Visit Website
The landscape epidemiology of foot-and-mouth disease in South Africa: A spatially-explicit multi-agent simulation
Elise Diona, Louis VanSchalkwyk, Eric Lambin

This study aimed at understanding how landscape heterogeneity influences outbreaks of contagious diseases in southern Africa. A multi-agent simulation was developed to represent the spatial and temporal dynamics of pathogens between human-livestock and wildlife interfaces at the fringe of large wildlife conservation areas. Results show that cattle–buffalo contacts mostly depend on the range of displacements of cattle and buffaloes, as influenced by the landscape configuration, and on the number of fence breakages multiplied by the time between breakage and repair.

Water, Sanitation and Health Sub-Saharan Africa Sunday, July 10, 2011 Visit Website
The Effect of Handwashing at Recommended Times with Water Alone and With Soap on Child Diarrhea in Rural Bangladesh: An Observational Study
Stephen Luby, Halder AK, Huda T, Unicomb L, Johnston RB

This observational study was conducted in rural Bangladesh among low-income communities. The findings suggest that handwashing before preparing food is an important opportunity to prevent childhood diarrhea, and also that handwashing with water alone can significantly reduce childhood diarrhea. This is the first study to find that handwashing with water alone can lead to health benefits.

Water, Sanitation and Health South Asia Tuesday, June 28, 2011 Visit Website
Expanding the boundaries of agricultural development

This paper explores several ways in which the traditional field of agricultural development needs to expand to address the broader issues of international security and human welfare. It focuses on five key interrelated issues: the macroeconomic and energy contexts of agricultural development; climate change; deforestation, land access, and land markets; farming systems and technology for the ultra-poor; and food-health linkages with a specific focus on infectious disease.

WASH and Development Other Thursday, April 21, 2011 Visit Website
Water supply services for Africa's urban poor: the role of resale
Valentina Zuin, Len Ortolano, Manuel Alvarinho, Kory Russel, Anne Thebo, Odete Muximpua , Jenna Davis

Water resale is often prohibited because of concerns about affordability and risks to public health. Using data collected from 1,377 households in Maputo, Mozambique, this study compares the microbiological quality, as well as the time and money costs of water supply from individual house connections, public standpipes, and water obtained from neighbors. Resale competes favorably with standpipes along a number of service quality dimensions; however, after controlling for water supply characteristics, households purchasing water from neighbors are significantly less likely to be satisfied with their water service as compared with those using standpipes.

Expanding Access Sub-Saharan Africa Saturday, January 1, 2011 Visit Website
The Effects of Informational Interventions on Household Water Management, Hygiene Behaviors, Stored Drinking Water Quality, and Hand Contamination in Peri-Urban Tanzania
Jenna Davis, Amy Pickering, Kirsten Rogers, Simon Mamuya, Ali Boehm

This study investigates the extent to which personalized information about Escherichia coli contamination of stored water and hands influenced knowledge, reported behaviors, and subsequent contamination levels among 334 households with less than 5-year-old children in peri-urban Dar es Salaam, Tanzania. Findings from this study suggest that additional work is needed to elucidate the conditions under which such testing represents a cost-effective strategy to motivate improved household water management and hand hygiene.

Water, Sanitation and Health Sub-Saharan Africa Saturday, January 1, 2011 Visit Website
Food security in an era of economic volatility
Rosamond Naylor, Walter P. Falcon

In this article, Naylor and Falcon delineate the nature and causes of recent food price volatility, gauge whether movements in world prices for the major cereal crops (maize, wheat, and rice) are good indicators of movements in food prices actually paid by poor households, and delve deeper into the question of how price instability affects food security among different groups in low-income countries. Three main factors distinguish food price volatility in the twenty-first century and underlie the authors' analysis: the important role of financial markets in determining international and domestic commodity prices; the new connection between agriculture and energy markets; and changes in agricultural trade policies that have caused some developing countries to rely more heavily than previously on trade in staples, and other to move toward self-sufficiency.

WASH and Development Other Wednesday, December 15, 2010 Visit Website
Bacterial hand contamination among Tanzanian mothers varies temporally and following household activities
Amy Pickering, Timothy R. Julian, Simon Mamuya, Ali Boehm, Jenna Davis

This study characterized the mechanisms of hand contamination with faecal indicator bacteria and assessed the presence of selected pathogens on mothers’ hands in Tanzania. The results showed that Escherichia coli and enterococci on hands can be significantly increased by various household activities, including those involving the use of soap and water. Thus, faecal indicator bacteria should be considered highly variable when used as indicators of handwashing behaviour.

Water, Sanitation and Health Sub-Saharan Africa Tuesday, November 23, 2010 Visit Website
Global land use change, economic globalization, and the looming land scarcity
Eric Lambin, Patrick Meyfroidt

This paper analyzes the challenges and opportunities for preserving natural forest ecosystems while enhancing food production in tropical developing countries under conditions of scarcity of unused productive cropland and economic globalization. It does so by drawing on examples from a few developing countries that have succeeded in increasing simultaneously their forest cover and agricultural production. These successes suggest that designing policies to reconcile development with nature conservation requires understanding land change as part of global-scale, open systems.

WASH and Development Other Sunday, November 21, 2010 Visit Website
Pathogenic landscapes: Interactions between land, people, disease vectors, and their animal hosts
Eric Lambin, Annelise Tran, Sophie O Vanwambeke, Catherine Linard, Valérie Soti

This study presents a review of the key findings from eight case studies that the authors conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium.

Water, Sanitation and Health Sub-Saharan Africa Wednesday, October 27, 2010 Visit Website