Neff R.A.,Johns Hopkins Center for a Livable Future
Food Policy | Year: 2015
With increasing global urbanization and environmental threats, ensuring food security for poor city residents is a critical challenge. An ongoing debate is whether urban agriculture (UA) may serve as a pathway to food security for poor urban households. To assess this potential within low-income countries, we used standard systematic review procedures to synthesize findings from 35 peer-reviewed journal articles from 1980 to 2013 that presented data on UA and food security indicators. Though data quality was often lacking, several key findings emerged. Many of the reviewed studies found subsistence to be the primary motivation for practicing UA, followed by financial benefit, with UA substantially contributing to farming households' food availability in some settings. Results regarding UA's impact on dietary diversity reveal that in some farming systems UA may provide households with greater access to specific foods. Evidence also indicates that UA can be a key source of household income, though actual returns were low. Furthermore, results show that UA can facilitate women's contribution to household food availability amid other household responsibilities, and can provide distinct benefits such as economic and social advancement. Although UA participation does not appear to fully eliminate pressure urban households face in obtaining food, a lack of supportive policies may constrain its potential. Municipal planning and agricultural policies that more effectively incorporate UA-and that integrate gender-may diminish barriers to productive UA practice. More rigorous research on UA's contribution to food security in settings where supportive policies have been enacted would more clearly elucidate these linkages. © 2015 Elsevier Ltd.
Nachman K.E.,Johns Hopkins Center for a Livable Future |
Baron P.A.,Johns Hopkins Center for a Livable Future |
Raber G.,University of Graz |
Francesconi K.A.,University of Graz |
Love D.C.,Johns Hopkins Center for a Livable Future
Environmental Health Perspectives | Year: 2013
Background: Inorganic arsenic (iAs) causes cancer and possibly other adverse health outcomes. Arsenic-based drugs are permitted in poultry production; however, the contribution of chicken consumption to iAs intake is unknown. Objectives: We sought to characterize the arsenic species profile in chicken meat and estimate bladder and lung cancer risk associated with consuming chicken produced with arsenic-based drugs. Methods: Conventional, antibiotic-free, and organic chicken samples were collected from grocery stores in 10 U.S. metropolitan areas from December 2010 through June 2011. We tested 116 raw and 142 cooked chicken samples for total arsenic, and we determined arsenic species in 65 raw and 78 cooked samples that contained total arsenic at ≥ 10 μg/kg dry weight. Results: The geometric mean (GM) of total arsenic in cooked chicken meat samples was 3.0 μg/kg (95% CI: 2.5, 3.6). Among the 78 cooked samples that were speciated, iAs concentrations were higher in conventional samples (GM = 1.8 μg/kg; 95%1.4, 2.3) than in antibiotic-free (GM = 0.7 μg/kg; 95%0.5, 1.0) or organic (GM = 0.6 μg/kg; 95%0.5, 0.8) samples. Roxarsone was detected in 20 of 40 conventional samples, 1 of 13 antibiotic-free samples, and none of the 25 organic samples. iAs concentrations in roxarsone-positive samples (GM = 2.3 μg/kg; 95%1.7, 3.1) were significantly higher than those in roxarsone-negative samples (GM = 0.8 μg/kg; 95%0.7, 1.0). Cooking increased iAs and decreased roxarsone concentrations. We estimated that consumers of conventional chicken would ingest an additional 0.11 μg/day iAs (in an 82-g serving) compared with consumers of organic chicken. Assuming lifetime exposure and a proposed cancer slope factor of 25.7 per milligram per kilogram of body weight per day, this increase in arsenic exposure could result in 3.7 additional lifetime bladder and lung cancer cases per 100,000 exposed persons. Conclusions: Conventional chicken meat had higher iAs concentrations than did conventional antibiotic-free and organic chicken meat samples. Cessation of arsenical drug use could reduce exposure and the burden of arsenic-related disease in chicken consumers.
Nachman K.E.,Johns Hopkins Center for a Livable Future |
Schwartz B.S.,Geisinger Health System
JAMA Internal Medicine | Year: 2013
IMPORTANCE: Nearly 80% of antibiotics in the United States are sold for use in livestock feeds. The manure produced by these animals contains antibiotic-resistant bacteria, resistance genes, and antibiotics and is subsequently applied to crop fields, where it may put community members at risk for antibiotic-resistant infections. OBJECTIVE: To assess the association between individual exposure to swine and dairy/veal industrial agriculture and risk of methicillin-resistant Staphylococcus aureus (MRSA) infection. DESIGN, SETTING, AND PARTICIPANTS: A population-based, nested case-control study of primary care patients from a single health care system in Pennsylvania from 2005 to 2010. Incident MRSA cases were identified using electronic health records, classified as community-associated MRSA or health care-associated MRSA, and frequency matched to randomly selected controls and patients with skin and soft-tissue infection. Nutrient management plans were used to create 2 exposure variables: seasonal crop field manure application and number of livestock animals at the operation. In a substudy, we collected 200 isolates from patients stratified by location of diagnosis and proximity to livestock operations. MAIN OUTCOMES AND MEASURES: Community-associated MRSA, health care-associated MRSA, and skin and soft-tissue infection status (with no history of MRSA) compared with controls. RESULTS: From a total population of 446 480 patients, 1539 community-associated MRSA, 1335 health care-associated MRSA, 2895 skin and soft-tissue infection cases, and 2914 controls were included. After adjustment for MRSA risk factors, the highest quartile of swine crop field exposure was significantly associated with community-associated MRSA, health care-associated MRSA, and skin and soft-tissue infection case status (adjusted odds ratios, 1.38 [95% CI, 1.13-1.69], 1.30 [95% CI, 1.05-1.61], and 1.37 [95% CI, 1.18-1.60], respectively); and there was a trend of increasing odds across quartiles for each outcome (P <.01 for trend in all comparisons). There were similar but weaker associations of swine operations with community-associated MRSA and skin and soft-tissue infection. Molecular testing of 200 isolates identified 31 unique spa types, none of which corresponded to CC398 (clonal complex 398), but some have been previously found in swine. CONCLUSIONS AND RELEVANCE: Proximity to swine manure application to crop fields and livestock operations each was associated with MRSA and skin and soft-tissue infection. These findings contribute to the growing concern about the potential public health impacts of high-density livestock production. © 2013 American Medical Association. All rights reserved.
News Article | November 16, 2016
New Johns Hopkins Bloomberg School of Public Health-led research suggests that some workers at industrial hog production facilities are not only carrying livestock-associated, antibiotic-resistant bacteria in their noses, but may also be developing skin infections from these bacteria. The findings are published Nov. 16 in PLOS ONE. "Before this study, we knew that many hog workers were carrying livestock-associated and multidrug-resistant Staphylococcus aureus strains in their noses, but we didn't know what that meant in terms of worker health," says study leader Christopher D. Heaney, PhD, an assistant professor at the Bloomberg School's departments of Environmental Health and Engineering, and Epidemiology. "It wasn't clear whether hog workers carrying these bacteria might be at increased risk of infection. This study suggests that carrying these bacteria may not always be harmless to humans." Because the study was small, the researchers say there is a need to confirm the findings, but the results highlight the need to identify ways to protect workers from being exposed to these bacteria on the job, and to take a fresh look at antibiotic use and resistance in food animal production. Hogs are given antibiotics in order to grow them more quickly for sale, and the overuse of antibiotics has been linked to the development of bacteria that are resistant to many of the drugs used to treat staph infections. The researchers, involving collaborators at the University of North Carolina at Chapel Hill, the Rural Empowerment Association for Community Help in Warsaw, NC, and the Statens Serum Institut in Copenhagen, enrolled 103 hog workers in North Carolina and 80 members of their households (either children or other adults) to have their noses swabbed to determine whether they were carrying strains of S. aureus in their nasal passages. Each person was also shown pictures of skin and soft tissue infections caused by S. aureus and asked if they had developed those symptoms in the previous three months. The researchers found that 45 of 103 hog workers (44 percent) and 31 of 80 household members (39 percent) carried S. aureus in their noses. Nearly half of the S. aureus strains being carried by hog workers were mutidrug-resistant and nearly a third of S. aureus strains being carried by household members were. Six percent of the hog workers and 11 percent of the children who lived with them reported a recent skin and soft tissue infection (no adult household members reported such infections). Those hog workers who carried livestock-associated S. aureus in their noses were five times as likely to have reported a recent skin or soft tissue infection as those who didn't carry those bacteria in their noses. The association was stronger among hog workers who carried multidrug-resistant S. aureus in their noses, who were nearly nine times as likely to have reported a recent skin or soft tissue infection. Multidrug-resistant S. aureus infections can be difficult to treat because the antibiotic drugs that doctors typically prescribe don't work. Researchers are concerned about what might happen if these bacteria develop the capacity to spread more broadly between animals and humans. While the study is small, Heaney says the findings suggest that more work is needed to figure out how to mitigate S. aureus exposure and the risk of infection among workers and to track the extent to which these livestock-associated bacteria may spread into the community at large. Since the study found that those hog workers who never wore protective masks over their nose and mouth were more likely to be carriers of the bacteria than those who did, Heaney says recommendations about wearing personal protective equipment might be prudent. Heaney says 89 percent of the hog workers in the study were Hispanic and that many are likely without health insurance. Studies like this, he says, can help focus on risks to a population that is vulnerable and may otherwise fall through the cracks. According to a Duke University analysis of U.S. Bureau of Labor Statistics data, roughly 327,350 people were employed in hog farming in the United States in 2012. Most evidence about the burden of human infections associated with drug-resistant S. aureus nasal colonization comes from studying strains that circulate in hospital settings, where patients are often tested upon admission so that medical staff can take precautions. Less is known about whether generally healthy people in the community, such as hog workers, are at increased risk of developing S. aureus infections. The rise of multidrug-resistant bacteria - often called superbugs - is a global crisis according to the World Health Organization and the use of antibiotics in food animal production has been highlighted as an important contributor. Roughly 80 percent of antibiotics sold in the United States are used in animals, with heavy nontherapeutic uses in food animal production. "This issue isn't going away and there are many more research questions that need to be answered," he says. "Livestock-associated, antibiotic-resistant Staphylococcus aureus nasal carriage and recent skin and soft tissue infection among industrial hog operation workers" was written by Maya Nadimpalli, Jill R. Stewart, Elizabeth Pierce, Nora Pisanic, David C. Love, Devon Hall, Jesper Larsen, Karen C. Carroll, Tsigereda Tekle, Trish M. Perl and Christopher D. Heaney. Funding for this study was provided by the National Institute for Occupational Safety and Health (1K01OH010193-01A1), the Johns Hopkins NIOSH Education and Research Center, the Johns Hopkins Center for a Livable Future, the Sherrilyn and Ken Fisher Center for Environmental Infectious Diseases Discovery Program at the Johns Hopkins University School of Medicine (018HEA2013), the National Science Foundation (1316318), the National Institute of Environmental Health Sciences (5T32ES007141-30), the Royster Society fellowship, an Environmental Protection Agency Science to Achieve Results fellowship the GRACE Communications Foundation and the National Institute for Allergy and Infectious Diseases (1R01AI101371-01A1).
News Article | December 7, 2016
Scientists have discovered a dangerous and highly transmissible form of multidrug-resistant bacteria lurking on a Midwestern hog farm, according to a study published yesterday. The bacteria have easily shared bits of DNA that help them fight off antibiotics called carbapenems, and this is the first time such microbes have been found on a U.S. farm. When these bacteria infect humans, they are extremely difficult to treat, and are often deadly. The discovery also poses something of a mystery. Carbapenems are not used on farms—they are mostly used in hospitals—so it is perplexing that microbes developed abilities to withstand a drug they probably did not encounter. The feat illustrates the ease with which antibiotic resistance traits travel to new locations and jump into different species, but it is still unclear what the findings mean for public health. As yet there is “no evidence that it is entering the food supply,” says Thomas Wittum, a scientist at The Ohio State University College of Veterinary Medicine who published the findings in Antimicrobial Agents and Chemotherapy along with his colleagues. “It is a rare resistant strain on a single farm,” he adds. “We will need to do a lot more research before we can say what exactly the risk is.” The researchers collected samples over the course of four visits to a farm that raises 1,500 hogs a year. They swabbed surfaces that come into contact with both animals and farm employees: crate bars, pen gates, floor mats, doorknobs and feed scoops, among other things. They also collected some hog rectal swabs and fecal samples. Wittum and his colleagues found that 18 samples, collected from surfaces that housed piglets and sows, harbored bacteria called carbapenem-resistant Enterobacteriaceae (CRE). The gene that helped them withstand the antibiotic was on a circular piece of DNA called a plasmid, and this particular circle is notorious for its ability to share copies of itself with other bacterial species in the presence of other “helper” plasmids. Indeed, “the striking evidence from this study is that they found [the resistance gene] in multiple species of bacteria, and that strongly suggests that it has moved around,” says Tim Johnson, a microbiologist at the University of Minnesota College of Veterinary Medicine. A study published in January 2016 found carbapenem-resistant bacteria in dairy cow manure on farms in New Mexico and Texas—yet these resistance genes were not on plasmids, but rather on bacterial chromosomes, which are not shared in the same way. No one is sure where these resistance genes came from or how they got to the farm but researchers have ideas. “The most logical source would be a hospital, where carbapenems are frequently used and CRE are not uncommon,” Wittum says. Farm workers might, for instance, carry CRE home from a hospital visit and then deposit the bacteria on farm equipment. But even if some bacteria were left on a doorknob by a farm employee, why did the microbes with the resistance trait stick around in animals? Resistance typically does not persist if it is not useful—and it is difficult to see the advantage of carrying a shield against an antibiotic that is not used in agriculture. One possibility is that a different antibiotic used on pigs, called ceftiofur, might be to blame. Ceftiofur molecules are structurally similar to carbapenems, and because of that genes that confer resistance to one frequently provide resistance to the other. This scenario is supported by the fact that researchers did not find CRE in samples collected from barns housing older hogs; ceftiofur is only used in young animals, and the resistance may dissipate as the hogs get older. Studies have shown that bacteria passed from people to animals can then evolve in ways to make them more dangerous. In a 2012 study published in Mbio, researchers reported that a strain of methicillin-resistant Staphylococcus aureus (MRSA) in Europe acquired its methicillin resistance as well as resistance to another drug, tetracycline, after jumping from people into pigs on farms. Then it jumped back into people again, causing serious illness. One cannot help but worry, says Keeve Nachman, director of the Food Production and Public Health Program at the Johns Hopkins Center for a Livable Future, that additional harmful genes will get off the farm in the future.
Hager E.R.,University of Maryland Baltimore County |
Cockerham A.,University of Maryland Baltimore County |
O'Reilly N.,Boise State University |
Harrington D.,University of Maryland, Baltimore |
And 3 more authors.
Public Health Nutrition | Year: 2016
Objective: To determine whether living in a food swamp (≥4 corner stores within 0·40 km (0·25 miles) of home) or a food desert (generally, no supermarket or access to healthy foods) is associated with consumption of snacks/desserts or fruits/vegetables, and if neighbourhood-level socio-economic status (SES) confounds relationships. Design: Cross-sectional. Assessments included diet (Youth/Adolescent FFQ, skewed dietary variables normalized) and measured height/weight (BMI-for-age percentiles/Z-scores calculated). A geographic information system geocoded home addresses and mapped food deserts/food swamps. Associations examined using multiple linear regression (MLR) models adjusting for age and BMI-for-age Z-score. Setting: Baltimore City, MD, USA. Subjects: Early adolescent girls (6th/7th grade, n 634; mean age 12·1 years; 90·7 % African American; 52·4 % overweight/obese), recruited from twenty-two urban, low-income schools. Results: Girls’ consumption of fruit, vegetables and snacks/desserts: 1·2, 1·7 and 3·4 servings/d, respectively. Girls’ food environment: 10·4 % food desert only, 19·1 % food swamp only, 16·1 % both food desert/swamp and 54·4 % neither food desert/swamp. Average median neighbourhood-level household income: $US 35 298. In MLR models, girls living in both food deserts/swamps consumed additional servings of snacks/desserts v. girls living in neither (β=0·13, P=0·029; 3·8 v. 3·2 servings/d). Specifically, girls living in food swamps consumed more snacks/desserts than girls who did not (β=0·16, P=0·003; 3·7 v. 3·1 servings/d), with no confounding effect of neighbourhood-level SES. No associations were identified with food deserts or consumption of fruits/vegetables. Conclusions: Early adolescent girls living in food swamps consumed more snacks/desserts than girls not living in food swamps. Dietary interventions should consider the built environment/food access when addressing adolescent dietary behaviours. Copyright © The Authors 2016
Matts C.,Michigan State University |
Conner D.S.,University of Vermont |
Fisher C.,Johns Hopkins Center for a Livable Future |
Tyler S.,Michigan State University |
Hamm M.W.,Michigan State University
Renewable Agriculture and Food Systems | Year: 2016
Local food purchasing programs at institutions such as K-12 schools, colleges and hospitals offer benefits including supporting farms and local economies, encouraging more healthful eating habits of patrons and fostering closer connections between farmers and consumers. Increasing in number and expanding in breadth, Farm to Institution (FTI) markets are promising outlets that may fulfill social and economic motivations for farmers. However, significant challenges and barriers have kept many from participating; farmers interested in this market will incur transaction costs, with high negotiation costs in particular due to product differentiation (in this case, by provenance) and less established markets and terms. Researchers have just begun to study farmers' perspectives on FTI and, to date, have primarily done so through convenience sampling. By utilizing a representative farmer sample, this study provides a major contribution to FTI research. This survey study was designed to better understand Michigan vegetable farmers' interest and willingness to participate in institutional markets and to identify perceived barriers and opportunities. Michigan is an ideal location for this research as it boasts one of the most diverse sets of agricultural crops in the US, has an economy highly reliant on the food and agriculture industry and has thriving FTI activity with extensive, ongoing outreach, education and research. Results of this survey study showed that half (50%) of the respondents (n = 311) reported interest in selling to at least one institution type (of K-12 schools, colleges and hospitals), but only a small percentage (7%) had yet sold produce to institutions. The most frequently reported motivators to sell to institutions were supplying healthy foods to customers (77%), fair, steady prices (77%) and supplying local food to consumers (76%), indicating that farmers' motivations are largely based in social values. Smaller scale farmers (less than 25 acres) were significantly less likely to rate economic factors and help in meeting logistical challenges as important, which suggests that they see more potential social value in FTI markets while larger farmers will seek to minimize their transaction costs related to this market. This research can inform the development of scale-appropriate farmer education to foster this market opportunity and its contribution to regional food system development. As demand for local food increases, it is critical to further examine the viability of FTI markets and continue to understand the opportunities and challenges to farmers of different types and scales to participate. Copyright © Cambridge University Press 2015.
Neff R.A.,Johns Hopkins Center for a Livable Future |
Merrigan K.,George Washington University |
Wallinga D.,Natural Resources Defense Council
Health Affairs | Year: 2015
Food has become a prominent focus of US public health policy. The emphasis has been almost exclusively on what Americans eat, not what is grown or how it is grown. A field of research, policy, and practice activities addresses the food-health-agriculture nexus, yet the work is still often considered "alternative" to the mainstream. This article outlines the diverse ways in which agriculture affects public health. It then describes three policy issues: farm-to-school programming, sustainability recommendations in the Dietary Guidelines for Americans, and antibiotic use in animal agriculture. These issues illustrate the progress, challenges, and public health benefits of taking a food systems approach that brings together the food, agriculture, and public health fields. © 2015 Project HOPE.
PubMed | Johns Hopkins University, Brandeis University and Johns Hopkins Center for a Livable Future
Type: Journal Article | Journal: Health promotion practice | Year: 2015
Supermarket-based interventions are one approach to improving the local food environment and reducing obesity and chronic disease in low-income populations. We implemented a multicomponent intervention that aimed to reduce environmental barriers to healthy food purchasing in a supermarket in Southwest Baltimore. The intervention, Eat Right-Live Well! used: shelf labels and in-store displays promoting healthy foods, sales and promotions on healthy foods, in-store taste tests, increasing healthy food products, community outreach events to promote the intervention, and employee training. We evaluated program implementation through store environment, taste test session, and community event evaluation forms as well as an Employee Impact Questionnaire. The stocking, labeling, and advertising of promoted foods were implemented with high and moderate fidelity. Taste test sessions were implemented with moderate reach and low dose. Community outreach events were implemented with high reach and dose. Supermarket employee training had no significant impact on employees knowledge, self-efficacy, or behavioral intention for helping customers with healthy purchasing or related topics of nutrition and food safety. In summary, components of this intervention to promote healthy eating were implemented with varying success within a large supermarket. Greater participation from management and employees could improve implementation.
PubMed | Johns Hopkins Center for a Livable Future
Type: | Journal: Annual review of public health | Year: 2015
The US food system functions within a complex nexus of social, political, economic, cultural, and ecological factors. Among them are many dynamic pressures such as population growth, urbanization, socioeconomic inequities, climate disruption, and the increasing demand for resource-intensive foods that place immense strains on public health and the environment. This review focuses on the role that policy plays in defining the food system, particularly with regard to agriculture. It further examines the challenges of making the food supply safe, nutritious, and sustainable, while respecting the rights of all people to have access to adequate food and to attain the highest standard of health. We conclude that the present US food system is largely unhealthy, inequitable, environmentally damaging, and insufficiently resilient to endure the impacts of climate change, resource depletion, and population increases, and is therefore unsustainable. Thus, it is imperative that the US embraces policy reforms to transform the food system into one that supports public health and reflects the principles of human rights and agroecology for the benefit of current and future generations.