New highways carry pathogens and social change in Ecuador

December 04, 2006

ANN ARBOR, Mich.---Logging roads have brought a higher incidence of diarrheal disease and new social problems among communities along the Ecuadorian coast, according to a new study by an international research team led by Joseph Eisenberg, assistant professor of epidemiology at the University of Michigan School of Public Health. The new roads connect Ecuadorian villages that previously used only rivers for transport. The study suggests the importance of considering human costs when assessing the environmental impacts of large development projects. With funding from the National Institutes of Allergy and Infectious Disease, the research team examined diarrheal infections and social networks in 21 villages being connected to a new road network built by the Ecuadorian government at the southern end of the Chocó rainforest, near the Pacific Ocean and the border with Columbia.

The roads bring new people to the villages, and allow the villagers to travel more easily between villages, and also back-and-forth to larger cities. But bacteria, viruses and parasites hitch rides with the newly-mobile people, adding new strains of old bugs to the local environment and increasing infection rates, according to Eisenberg. "If you keep reintroducing strains of a given pathogen, you're increasing the endemic population of pathogens," he said.

The study looked in particular at E. coli bacteria, rotavirus and the protozoan parasite Giardia, finding different infection rates and modes of transmission for each, but the same overall trends: proximity to the road meant higher infection rates. Remote villages were found to have infection rates up to eight times lower than those close to the new road.

"The increased diversity and potency of the microbe population apparently offsets the improved health care that also comes with new roads," he said. "When you're thinking about a road, you have to also think about these impacts that will take years to unfold."

The newly busy towns also seemed to experience a breakdown of traditional social structure and supports, leading to poorer sanitation, Eisenberg said. Borbón, the boom town at the hub of the new road network, has grown to more than 1,000 homes and has an ominous "fecal film" on its river.

"When the tide goes down and you look at the river bank, you can see a number of pipes leading from all sorts of buildings," Eisenberg said.

To gather these measures, the team's surveyors visited each village three times over the course of two years. During each 15-day visit, they stopped at every home daily, asking if anyone was sick and collecting stool samples to identify the organism causing the illness.

In addition to tracking the movement and identity of diarrheal diseases, they interviewed all the villagers about their social contacts and built a social network map as a way to measure social cohesion. Social cohesion affects the maintenance of infrastructure, which is relevant to disease transmission, Eisenberg said. "The higher social cohesion is, the cleaner the village," he said.

Numerous studies have linked infectious disease with roads and road construction, including HIV transmission in Uganda and malaria in Peru, but the effects of roads on diarrheal diseases, which are a leading cause of mortality among infants and children under age 5, are relatively unknown.
-end-
The study "Environmental change and infectious disease: How new roads affect the transmission of diarrheal pathogens in rural Ecuador" appears in the Proceedings of the National Academy of Sciences the week of Dec. 4. Authors include colleagues from the University of California at Berkeley, Universidad San Francisco de Quito, Ecuador, and Trinity College in Hartford, Conn.

LINKS



Joseph Eisenberg - www.sph.umich.edu/iscr/faculty/profile.cfm"uniqname=jnse
U-M School of Public Health - www.sph.umich.edu

University of Michigan

Related Public Health Articles from Brightsurf:

COVID-19 and the decolonization of Indigenous public health
Indigenous self-determination, leadership and knowledge have helped protect Indigenous communities in Canada during the coronavirus disease 2019 (COVID-19) pandemic, and these principles should be incorporated into public health in future, argue the authors of a commentary in CMAJ (Canadian Medical Association Journal) http://www.cmaj.ca/lookup/doi/10.1503/cmaj.200852.

Public health consequences of policing homelessness
In a new study examining homelessness, researchers find that policy such a lifestyle has massive public health implications, making sleeping on the street even MORE unhealthy.

Electronic health information exchange improves public health disease reporting
Disease tracking is an important area of focus for health departments in the midst of the COVID-19 pandemic.

Pandemic likely to cause long-term health problems, Yale School of Public Health finds
The coronavirus pandemic's life-altering effects are likely to result in lasting physical and mental health consequences for many people--particularly those from vulnerable populations--a new study led by the Yale School of Public Health finds.

The Lancet Public Health: US modelling study estimates impact of school closures for COVID-19 on US health-care workforce and associated mortality
US policymakers considering physical distancing measures to slow the spread of COVID-19 face a difficult trade-off between closing schools to reduce transmission and new cases, and potential health-care worker absenteeism due to additional childcare needs that could ultimately increase mortality from COVID-19, according to new modelling research published in The Lancet Public Health journal.

The Lancet Public Health: Access to identification documents reflecting gender identity may improve trans mental health
Results from a survey of over 20,000 American trans adults suggest that having access to identification documents which reflect their identified gender helps to improve their mental health and may reduce suicidal thoughts, according to a study published in The Lancet Public Health journal.

The Lancet Public Health: Study estimates mental health impact of welfare reform, Universal Credit, in Great Britain
The 2013 Universal Credit welfare reform appears to have led to an increase in the prevalence of psychological distress among unemployed recipients, according to a nationally representative study following more than 52,000 working-age individuals from England, Wales, and Scotland over nine years between 2009-2018, published as part of an issue of The Lancet Public Health journal on income and health.

BU researchers: Pornography is not a 'public health crisis'
Researchers from the Boston University School of Public Health (BUSPH) have written an editorial in the American Journal of Public Health special February issue arguing against the claim that pornography is a public health crisis, and explaining why such a claim actually endangers the health of the public.

The Lancet Public Health: Ageism linked to poorer health in older people in England
Ageism may be linked with poorer health in older people in England, according to an observational study of over 7,500 people aged over 50 published in The Lancet Public Health journal.

Study: Public transportation use linked to better public health
Promoting robust public transportation systems may come with a bonus for public health -- lower obesity rates.

Read More: Public Health News and Public Health Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.