Validation of good agricultural practices (GAP) on Minnesota vegetable farms.

The United States Food and Drug Administration and the Department of Agriculture jointly published the "Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables," which is used as a basis for Good Agricultural Practices (GAP) audits. To understand barriers to incorporation of GAP by Minnesota vegetable farmers, a mail survey completed in 2008 was validated with visits to a subset of the farms. This was done to determine the extent to which actual practices matched perceived practices. Two hundred forty-six producers completed the mail survey, and 27 participated in the on-farm survey. Over 75% of the on-farm survey respondents produced vegetables on 10 acres or less and had 10 or fewer employees. Of 14 questions, excellent agreement between on-farm interviews and mail survey responses was observed on two questions, four questions had poor or slight agreement, and eight questions had no agreement. Ninety-two percent of respondents by mail said "they took measures to keep animals and pests out of packing and storage buildings." However, with the on-site visit only 45% met this requirement. Similarly, 81% of respondents by mail said "measures were taken to reduce the risk of wild and/or domestic animals entering into fruit and vegetable growing areas." With direct observation, 70% of farms actually had taken measures to keep animals out of the growing areas. Additional, on-farm assessments were done regarding employee hygiene, training, presence of animals, water sources, and composting practices. This validation study demonstrated the challenge of creating nonleading and concise questions that are not open to broad interpretation from the respondents. If mail surveys are used to assess GAP, they should include open-ended questions and ranking systems to better assess farm practices. To provide the most accurate survey data for educational purposes or GAP audits, on-farm visits are recommended.

Disease risk in a dynamic environment: the spread of tick-borne pathogens in Minnesota, USA.

As humans and climate change alter the landscape, novel disease risk scenarios emerge. Understanding the complexities of pathogen emergence and subsequent spread as shaped by landscape heterogeneity is crucial to understanding disease emergence, pinpointing high-risk areas, and mitigating emerging disease threats in a dynamic environment. Tick-borne diseases present an important public health concern and incidence of many of these diseases are increasing in the United States. The complex epidemiology of tick-borne diseases includes strong ties with environmental factors that influence host availability, vector abundance, and pathogen transmission. Here, we used 16 years of case data from the Minnesota Department of Health to report spatial and temporal trends in Lyme disease (LD), human anaplasmosis, and babesiosis. We then used a spatial regression framework to evaluate the impact of landscape and climate factors on the spread of LD. Finally, we use the fitted model, and landscape and climate datasets projected under varying climate change scenarios, to predict future changes in tick-borne pathogen risk. Both forested habitat and temperature were important drivers of LD spread in Minnesota. Dramatic changes in future temperature regimes and forest communities predict rising risk of tick-borne disease.