Edward R. Atwill's research while affiliated with University of California, Davis and other places

Publications (223)

Article
Full-text available
Coastal pollution is of public health concern due to the possibility of bacterial contamination in aquaculture affecting health risk and seafood safety. This study determined the concentrations of total coliforms, fecal coliforms, E. coli, and V. parahaemolyticus and the presence of V. cholerae and Salmonella in water and measured water quality and...
Article
Full-text available
The occurrence of waterborne antimicrobial-resistant (AMR) bacteria in areas of high-density oyster cultivation is an ongoing environmental and public health threat given the popularity of shellfish consumption, water-related human recreation throughout coastal Thailand, and the geographical expansion of Thailand’s shellfish industry. This study ch...
Article
Full-text available
Cryptosporidium spp. is a parasite that can infect a wide variety of vertebrate species. The parasite has been detected in sheep worldwide with diverse species and genotypes of various levels of zoonotic potential and public health concern. The purpose of this study was to determine the distribution of genotypes of Cryptosporidium in sheep in Calif...
Article
Full-text available
Pandemics caused by pathogens that originate in wildlife highlight the importance of understanding the behavioral ecology of disease outbreaks at human–wildlife interfaces. Specifically, the relative effects of human–wildlife and wildlife-wildlife interactions on disease outbreaks among wildlife populations in urban and peri-urban environments rema...
Article
Full-text available
Microbial food safety in cultured tilapia remains a challenge to public health worldwide, due in part to intensive aquaculture leading to poor water quality and high organic matter deposition. This study aimed to determine the prevalence of indicator and potential pathogenic bacteria in hybrid red tilapia (Oreochromis spp.) and their cultivation wa...
Article
Full-text available
Background Microbiota play important roles in the gastrointestinal tract (GIT) of dairy cattle as the communities are responsible for host health, growth, and production performance. However, a systematic characterization and comparison of microbial communities in the GIT of cattle housed in different management units on a modern dairy farm are sti...
Article
Full-text available
Produce-associated foodborne outbreaks have been increasingly implicated as the significant proportion of the annual incidence of foodborne illness worldwide. The objectives of this study were to determine the concentrations of indicator bacteria and the presence of Salmonella spp., Shigella spp., Escherichia coli O157:H7, and Listeria monocytogene...
Article
Full-text available
Produce-associated foodborne outbreaks have been increasingly implicated as the significant proportion of the annual incidence of foodborne illness worldwide. The objectives of this study were to determine the concentrations of indicator bacteria and the presence of Salmonella spp., Shigella spp., Escherichia coli O157:H7, and Listeria monocytogene...
Article
Full-text available
Consumption of contaminated food causes 600 million cases, including 420,000 of fatal infections every year. Estimated cost from food-borne illnesses is USD 110 billion per year, which is an economic burden to low- and middle-income countries. Thailand is a leading producer and consumer of seafood, but little is known about bacterial contamination...
Article
Full-text available
Background The presence of Escherichia coli O157:H7 ( E. coli O157:H7) super-shedding cattle in feedlots has the potential to increase the overall number (bio-burden) of E. coli O157:H7 in the environment. It is important to identify factors to reduce the bio-burden of E. coli O157 in feedlots by clarifying practices associated with the occurrence...
Article
Full-text available
The objectives of this study were to characterize overall genomic antibiotic resistance profiles of fecal Escherichia coli and Enterococcus spp. from dairy cattle at different production stages using whole-genome sequencing and to determine the association between antimicrobial resistance (AMR) phenotypes and their corresponding genotypes. The Comp...
Preprint
Full-text available
Pandemics caused by wildlife-origin pathogens, like COVID-19, highlight the importance of understanding the ecology of zoonotic transmission and outbreaks among wildlife populations at human-wildlife interfaces. To-date, the relative effects of human-wildlife and wildlife-wildlife interactions on the likelihood of such outbreaks remain unclear. In...
Article
Full-text available
Background Understanding the effects of herd management practices on the prevalence of multidrug-resistant pathogenic Salmonella and commensals Enterococcus spp. and Escherichia coli in dairy cattle is key in reducing antibacterial resistant infections in humans originating from food animals. Our objective was to explore the herd and cow level feat...
Article
Full-text available
Between October 2013 and May 2016, 506 scat samples were collected from 22 species of wildlife located in a protected watershed of a major municipal water supply in the Pacific Northwest, USA. Overall prevalence of Cryptosporidium in the wildlife scat was 13.8% (70/506), with 15 species of wildlife found positive for Cryptosporidium. Prevalence of...
Article
Bacterial attachment on surfaces is an important biological and industrial concern. Many parameters affect cell attachment behavior, including surface roughness and other topographical features. An understanding of these relationships is critical in the light of recent outbreaks caused by foodborne bacteria. Postharvest packing lines have been iden...
Preprint
Bacteria play important roles in the gastrointestinal tract (GIT) of dairy cattle as the communities are responsible for host health, growth and production performance. However, a systematic characterization and comparison of microbial communities in the GIT of cattle housed in different management units on a modern dairy are still lacking. In this...
Article
Full-text available
Epidemiological studies of low prevalence disease problems are often hindered by the high cost of diagnostic testing. The objective of this study was to evaluate PCR screening of both individual and pooled fecal samples from culled dairy cows for the inv A gene of Salmonella followed by culture to determine if the sensitivity and specificity were c...
Article
Full-text available
This study quantified the association of rodent fruit damage and the microbiological quality of irrigation water on the risk of microbiological contamination of strawberries collected from 18 U-pick farms across five different districts in the Guangzhou metropolitan region of southern China. Fifty-four composite strawberries samples, with or withou...
Article
Social status impacts stress in primates, but the direction of the effect differs depending on species, social style, and group stability. This complicates our ability to identify broadly applicable principles for understanding how social status impacts health and fitness. One reason for this is the fact that social status is often measured as line...
Article
Full-text available
This randomized controlled trial characterized the transfer of E. coli from animal feces and/or furrow water onto adjacent heads of lettuce during foliar irrigation, and the subsequent survival of bacteria on the adaxial surface of lettuce leaves. Two experiments were conducted in Salinas Valley, California: (1) to quantify the transfer of indicato...
Article
Full-text available
Time is a valuable but limited resource, and animals' survival depends on their ability to carefully manage the amount of time they allocate to each daily activity. While existing research has examined the ecological factors affecting animals' activity budgets, the impact of anthropogenic factors on urban-dwelling animals' time budgets remains unde...
Article
Full-text available
The objective of the study was to assess the microbiological safety of popular recreational swimming sites in Central California. Water samples were collected from eleven monitoring sites across the lower reaches of two watersheds for two consecutive swimming seasons (2012–2013), and levels of indicator and pathogenic microorganisms were determined...
Article
Full-text available
This study was performed to improve the ability to predict the concentrations of Escherichia coli in oyster meat and estuarine waters by using environmental parameters, and microbiological and heavy metal contamination from shellfish growing area in southern Thailand. Oyster meat (n = 144) and estuarine waters (n = 96) were tested for microbiologic...
Article
Full-text available
Abstract Background There is growing evidence to support the beneficial effects of supplementing direct-fed microbials (DFM) on performance, health status, and immune responses of weaned pigs. Therefore, the objective of this study was to investigate dietary supplementation of Bacillus subtilis (DSM 25841) on growth performance, diarrhea, gut perme...
Article
Full-text available
In social animals, affiliative behaviours bring many benefits, but also costs such as disease risk. The ways in which affiliation may affect the risk of infectious agent transmission remain unclear. Moreover, studies linking variation in affiliative interactions to infectious agent incidence/diversity have speculated that disease transmission may h...
Article
Full-text available
Background: In this study cull dairy cows from six California dairy herds were sampled seasonally over the course of a year. The objectives were to determine the prevalence of antimicrobial resistant (AMR) Salmonella spp. shed in cull cow feces, and the factors associated with fecal shedding of AMR and multidrug resistant (MDR) Salmonella. Method...
Article
Full-text available
Keywords: anthropogenic environment humanewildlife interactions nonhuman primates social interactions stress time constraints Humans and their associated anthropogenic factors may strongly affect the demographics, activity and fragmentation of wild animal populations. Yet, the degree and nature of such impact on indicators of animals' social relati...
Article
Full-text available
Field trials were conducted in July–August and October 2012 to quantify the inactivation rate of Escherichia coli O157:H7 when mixed with fecal slurry and applied to romaine lettuce leaves. Lettuce was grown under commercial conditions in Salinas Valley, California. One-half milliliter of rabbit, chicken, or pig fecal slurry, containing an average...
Article
Cryptosporidium spp. and Giardia duodenalis are common protozoal parasites in livestock including beef cattle on rangeland and irrigated pasture. A statewide cross-sectional study was conducted to determine the prevalence, species or genotype, and risk factors for fecal shedding of Cryptosporidium and Giardia by cattle from California cow-calf oper...
Article
Most of the commercially available β-glucans are derived from yeast, while there are limited research on algae-derived β-glucan in pigs. Therefore, the objective of this experiment was to investigate the influence of dietary supplementation of algae-derived β-glucan on diarrhea, gut permeability, and immune responses of weaned pigs experimentally i...
Article
There is growing evidence that anthropogenic sources of antibiotics and antimicrobial-resistant bacteria can spill over into natural ecosystems, raising questions about the role wild animals play in the emergence, maintenance, and dispersal of antibiotic resistance genes. In particular, we lack an understanding of how resistance genes circulate wit...
Article
Full-text available
Shiga toxin-producing Escherichia coli, like E. coli O157:H7, are important human and animal pathogens. Naturally-acquired E. coli O157:H7 infections occur in numerous species but, particularly, cattle have been identified as a significant reservoir for human cases. E. coli O157:H7 are isolated from a number of domestic and wild animals, including...
Article
Full-text available
This study characterized microbiological and chemical contamination of oyster meat and estuarine water in Phang Nga, Thailand. Pooled oyster meats (n = 144), estuarine waters (n = 96) and environmental parameters were collected from March, 2016 to February, 2017, and assessed for levels of total coliforms (TC), fecal coliforms (FC), Escherichia col...
Article
In 2011, the US Congress passed the Food Safety Modernization Act, which tasks the US Food and Drug Administration to establish microbiological standards for agricultural water. However, little data are available for the microbiological quality of surface water irrigation supplies. During the 2015 irrigation season, we conducted a baseline study on...
Data
Bipartite matrix containing information on the bacterial DNA fingerprint profiles of macaques Row labels represent each individual macaque (243 in total), and column labels represent each of 66 band positions identified and optimized using automated analytical parameters to fit the dataset. Cells indicate either a presence (1) or absence (0) of a b...
Data
Definitions of social network measures computed for each group to establish adequacy in network sampling effort, using both the original data and from bootstrapped datasets of reduced degrees of sampling effort
Data
Plots of the Newman’s eigenvector-based modularity of the grooming, huddling, and aggression network measures against % sampling effort for all three groups Data-points represent mean values computed from 1,000 networks (100 under each category of % sampling effort) permuted from each natural dataset, and error bars the standard deviations. Data-po...
Data
Dataset containing values of Newman’s modularity calculated for 1,000 permutations (100 iterations within each of 10%-100% sampling effort from the original dataset) of each behavioral network for each group
Data
Multivariate MR-QAP regression models examining the effects of dyadic social behavioral interactions on the % genetic similarity of E. coli
Article
Full-text available
In group-living animals, heterogeneity in individuals’ social connections may mediate the sharing of microbial infectious agents. In this regard, the genetic relatedness of individuals’ commensal gut bacterium Escherichia coli may be ideal to assess the potential for pathogen transmission through animal social networks. Here we use microbial phylog...
Article
California has one of the largest systems of surface water reservoirs in the world, providing irrigation water to California's agriculturally productive Central Valley. Irrigation water is recognized as a vehicle for the microbial contamination of raw produce and must be monitored according to new federal regulation. The purpose of this study was t...
Article
Full-text available
Escherichia coli serotype O157:H7 is a zoonotic food- and waterborne bacterial pathogen that causes a high hospitalization rate and can cause life-threatening complications. Increasingly, E. coli O157:H7 infections appear to originate from fresh produce. Ruminants, such as cattle, are a prominent reservoir of E. coli O157:H7 in the United States. C...
Article
Full-text available
A field trial was conducted in July 2011 to quantify the inactivation rate of Escherichia coli O157:H7 when mixed with fecal slurry and applied to romaine lettuce leaves. Lettuce was grown under commercial conditions in Salinas Valley, CA. One-half milliliter of rabbit fecal slurry, containing 6.3 ? 10(7) CFU of E. coli O157:H7, was inoculated onto...
Article
Full-text available
Deer mice ( Peromyscus maniculatus ) are abundant and widely distributed rodents in North America that occupy diverse habitats, including agricultural landscapes. Giardia and Cryptosporidium are common parasites in wildlife including deer mice, which may play a role in on-farm contamination of produce. An important step in assessing the risk of pro...
Article
Full-text available
Background Climate change produces extremes in both temperature and precipitation causing increased drought severity and increased reliance on groundwater resources. Agricultural practices, which rely on groundwater, are sensitive to but also sources of contaminants, including nitrate. How agricultural contamination drives groundwater geochemistry...
Data
VizBin clustering of the Planctomycete genomic bins shows evidence of at least 6 distinct genomes. See graphical legend to determine identity of each cluster. MW5-59_1 and MW5-59_2 may be strain variants because they overlap in their pentanucleotide distribution clustering but have distinct relative abundances (S1 Table). MW6-13 also overlaps the M...
Data
MetaPhlAn 1.0 analysis of short read data. MetaPhlAn 1.0 analysis of the short reads to estimate taxonomic relative abundance at the genus level. The color scale bar indicates the percentage of reads aligning to the indicated taxon reference sequences. (PDF)
Data
Planctomycete bin MW6-09 has best (but low) homology to the Singulisphaera acidiphilus. BRIG was used to align available Planctomycete reference genomes to the MW6-09 bin by blastn. Radial colored bars in the concentric rings indicate nucleotide homology (30–100%). See graphical legend for ring identities. Contig order is that of the MW6-09 genome....
Data
MW6 genomic bin statistics including taxonomic calls, coverage, assembly metrics, and completeness estimates. (XLSX)
Data
LAG genomic bin statistics including taxonomic calls, coverage, assembly metrics, and completeness estimates. (XLSX)
Data
Homology of assembled Brocadiaceae genomes to the Brocadia sinica reference genome. BRIG was used to compare the Brocadiaceae genomic bins to the reference Jettenia caeni by blastn. Radial colored bars in the concentric rings indicate nucleotide homology (30–100%). See graphical legend for ring identities. MW5 bins are shown in green, MW6 in red, a...
Data
Total bp for FASTQ sequences for reads passing QC. (DOCX)