Detecting national human enteric disease outbreaks linked to animal contact in the United States of America.

Enteric pathogens, such as non-typhoidal Salmonella, Campylobacter and Escherichia coli, can reside in the intestinal tract of many animals, including livestock, companion animals, small mammals and reptiles. Often, these animals can appear healthy; nonetheless, humans can become infected after direct or indirect contact, resulting in a substantial illness burden. An estimated 14% of the 3.2 million illnesses that occur in the United States of America (USA) each year from such enteric pathogens are attributable to animal contact. Surveillance for enteric pathogens in the USA includes the compilation and interpretation of both laboratory and epidemiologic data. However, the authors feel that a collaborative, multisectoral and transdisciplinary - or One Health - approach is needed for data collection and analysis, at every level. In addition, they suggest that the future of enteric illness surveillance lies in the development of improved technologies for pathogen detection and characterisation, such as genomic sequencing and metagenomics. In particular, using whole-genome sequencing to compare genetic sequences of enteric pathogens from humans, food, animals and the environment, can help to predict antimicrobial resistance among these pathogens, determine their genetic relatedness and identify outbreaks linked to a common source. In this paper, the authors describe three recent, multi-state human enteric illness outbreaks linked to animal contact in the USA and discuss how integrated disease surveillance was essential to outbreak detection and response. Additional datasharing between public health and animal health laboratories and epidemiologists at the local, national, regional and international level may help to improve surveillance for emerging animal and human health threats and lead to new opportunities for prevention.

Les agents pathogènes entériques tels que les Salmonella non typhiques, Campylobacter et Escherichia coli peuvent coloniser le tractus intestinal d'un grand nombre d'animaux y compris les espèces d'élevage, les animaux de compagnie, les petits mammifères et les reptiles. Les animaux porteurs sont souvent sains en apparence ; néanmoins, les humains peuvent contracter l'infection après un contact direct ou indirect avec un animal atteint, ce qui induit un fardeau significatif associé à ces maladies. D'après les estimations, environ 14 % des 3,2 millions de cas annuels d'infections par des agents pathogènes entériques aux États-Unis d'Amérique ont pour origine un contact avec des animaux. Aux États-Unis, la surveillance des agents pathogènes entériques est basée sur la collecte et l'interprétation des résultats de laboratoire et des données épidémiologiques. Les auteurs sont néanmoins convaincus de la nécessité de recourir à une approche collaborative, multisectorielle et transdisciplinaire (en d'autres termes, une approche Une seule santé) pour la collecte et l'analyse des données, à tous les niveaux. Ils considèrent également que la surveillance des infections entériques reposera à l'avenir sur le développement de technologies avancées dans le domaine de la détection et de la caractérisation des agents pathogènes, notamment le séquençage génomique et la métagénomique. En particulier, le recours au séquençage du génome entier afin de comparer les séquences d'agents pathogènes d'origine humaine, alimentaire, animale et environnementale permettra d'anticiper l'apparition d'antibiorésistances, de déterminer le degré de parenté génétique de ces agents et d'identifier les foyers provenant d'une même source. Les auteurs décrivent trois foyers récents d'infections entériques humaines survenus dans plusieurs états des États-Unis et soulignent à quel point l'exercice d'une surveillance sanitaire intégrée a été déterminant pour la détection de ces foyers et la mise en œuvre d'une réponse appropriée. Un partage accru d'informations entre les laboratoires et les épidémiologistes de santé publique et animale aux niveaux local, national, régional et international pourrait contribuer à améliorer la surveillance des menaces émergentes pesant sur la santé animale et humaine et à mettre en œuvre de nouvelles modalités de prévention.

En el tracto intestinal de muchos animales, entre ellos ganado, mascotas, pequeños mamíferos o reptiles, puede haber patógenos intestinales como salmonelas no tifoideas, Campylobacter o Escherichia coli. A menudo los animales parecen sanos, pese a lo cual las personas pueden infectarse por contacto directo o indirecto con ellos, lo que da lugar a una considerable carga de morbilidad. Se calcula que, de los 3,2 millones de casos de enfermedad que estos patógenos intestinales causan al año en los EE. UU., un 14% es atribuible al contacto con animales. La vigilancia de patógenos intestinales que se practica en los EE. UU. incluye la compilación e interpretación de datos tanto epidemiológicos como de laboratorio. En opinión de los autores, sin embargo, es preciso que la obtención y el análisis de datos respondan a un planteamiento de colaboración multisectorial y transdisciplinar ­ esto es, a la lógica de Una sola salud ­ que abarque todos los niveles. Los autores apuntan además que el futuro de la vigilancia de las enfermedades intestinales pasa por el desarrollo de tecnologías más eficaces de detección y caracterización de patógenos, como la secuenciación genómica o la metagenómica. En particular, el uso de la secuenciación de genomas completos para comparar entre sí las secuencias genéticas de patógenos intestinales presentes en personas, alimentos, animales y el medio ambiente puede ayudar a predecir la aparición de resistencias a los antimicrobianos en estos patógenos, determinar su parentesco genético e identificar brotes vinculados con un origen común. Los autores, tras describir tres recientes brotes de enfermedad intestinal humana ligados al contacto con animales que afectaron a varios estados de los EE. UU., explican la función esencial que cumplió la vigilancia integrada de enfermedades para detectar esos brotes y responder a ellos. El intercambio de más datos entre los laboratorios de salud pública y sanidad animal y los epidemiólogos a escala local, nacional, regional e internacional puede ser de ayuda para mejorar la vigilancia de amenazas sanitarias y zoosanitarias emergentes y abrir nuevas posibilidades de prevención.

New product, old problem(s): multistate outbreak of Salmonella Paratyphi B variant L(+) tartrate(+) infections linked to raw sprouted nut butters, October 2015.

A cluster of Salmonella Paratyphi B variant L(+) tartrate(+) infections with indistinguishable pulsed-field gel electrophoresis patterns was detected in October 2015. Interviews initially identified nut butters, kale, kombucha, chia seeds and nutrition bars as common exposures. Epidemiologic, environmental and traceback investigations were conducted. Thirteen ill people infected with the outbreak strain were identified in 10 states with illness onset during 18 July-22 November 2015. Eight of 10 (80%) ill people reported eating Brand A raw sprouted nut butters. Brand A conducted a voluntary recall. Raw sprouted nut butters are a novel outbreak vehicle, though contaminated raw nuts, nut butters and sprouted seeds have all caused outbreaks previously. Firms producing raw sprouted products, including nut butters, should consider a kill step to reduce the risk of contamination. People at greater risk for foodborne illness may wish to consider avoiding raw products containing raw sprouted ingredients.

An outbreak of Escherichia coli O157:H7 infections following a dairy education school field trip in Washington state, 2015.

On 27 April 2015, Washington health authorities identified Escherichia coli O157:H7 infections associated with dairy education school field trips held in a barn 20-24 April. Investigation objectives were to determine the magnitude of the outbreak, identify the source of infection, prevent secondary illness transmission and develop recommendations to prevent future outbreaks. Case-finding, hypothesis generating interviews, environmental site visits and a case-control study were conducted. Parents and children were interviewed regarding event activities. Odds ratios (OR) and 95% confidence intervals (CI) were computed. Environmental testing was conducted in the barn; isolates were compared to patient isolates using pulsed-field gel electrophoresis (PFGE). Sixty people were ill, 11 (18%) were hospitalised and six (10%) developed haemolytic uremic syndrome. Ill people ranged in age from <1 year to 47 years (median: 7), and 20 (33%) were female. Twenty-seven case-patients and 88 controls were enrolled in the case-control study. Among first-grade students, handwashing (i.e. soap and water, or hand sanitiser) before lunch was protective (adjusted OR 0.13; 95% CI 0.02-0.88, P = 0.04). Barn samples yielded E. coli O157:H7 with PFGE patterns indistinguishable from patient isolates. This investigation provided epidemiological, laboratory and environmental evidence for a large outbreak of E. coli O157:H7 infections from exposure to a contaminated barn. The investigation highlights the often overlooked risk of infection through exposure to animal environments as well as the importance of handwashing for disease prevention. Increased education and encouragement of infection prevention measures, such as handwashing, can prevent illness.

Multistate outbreak of Salmonella Paratyphi B variant L(+) tartrate(+) and Salmonella Weltevreden infections linked to imported frozen raw tuna: USA, March-July 2015.

Foodborne non-typhoidal salmonellosis causes approximately 1 million illnesses annually in the USA. In April 2015, we investigated a multistate outbreak of 65 Salmonella Paratyphi B variant L(+) tartrate(+) infections associated with frozen raw tuna imported from Indonesia, which was consumed raw in sushi. Forty-six (92%) of 50 case-patients interviewed ate sushi during the week before illness onset, and 44 (98%) of 45 who specified ate sushi containing raw tuna. Two outbreak strains were isolated from the samples of frozen raw tuna. Traceback identified a single importer as a common source of tuna consumed by case-patients; this importer issued three voluntary recalls of tuna sourced from one Indonesian processor. Four Salmonella Weltevreden infections were also linked to this outbreak. Whole-genome sequencing was useful in establishing a link between Salmonella isolated from ill people and tuna. This outbreak highlights the continuing foodborne illness risk associated with raw seafood consumption, the importance of processing seafood in a manner that minimises contamination with pathogenic microorganisms and the continuing need to ensure imported foods are safe to eat. People at higher risk for foodborne illness should not consume undercooked animal products, such as raw seafood.

Flea market finds and global exports: Four multistate outbreaks of human Salmonella infections linked to small turtles, United States-2015.

Zoonotic transmission of Salmonella infections causes an estimated 11% of salmonellosis annually in the United States. This report describes the epidemiologic, traceback and laboratory investigations conducted in the United States as part of four multistate outbreaks of Salmonella infections linked to small turtles. Salmonella isolates indistinguishable from the outbreak strains were isolated from a total of 143 ill people in the United States, pet turtles, and pond water samples collected from turtle farm A, as well as ill people from Chile and Luxembourg. Almost half (45%) of infections occurred in children aged <5 years, underscoring the importance of the Centers for Disease Control and Prevention recommendation to keep pet turtles and other reptiles out of homes and childcare settings with young children. Although only 43% of the ill people who reported turtle exposure provided purchase information, most small turtles were purchased from flea markets or street vendors, which made it difficult to locate the vendor, trace the turtles to a farm of origin, provide education and enforce the United States federal ban on the sale and distribution of small turtles. These outbreaks highlight the importance of improving public awareness and education about the risk of Salmonella from small turtles not only in the United States but also worldwide.

Milk production and composition from cows fed small amounts of fish oil with extruded soybeans.

Eight Holstein (189 +/- 57 DIM) and 4 Brown Swiss (126 +/- 49 DIM) multiparous cows were used in a replicated 4 x 4 Latin square with 28-d periods to determine the minimal dietary concentration of fish oil necessary to maximize milk conjugated linoleic acid (CLA) and vaccenic acid (VA). Treatments consisted of a control diet with a 50:50 ratio of forage to concentrate (dry matter basis), and 3 diets with 2% added fat consisting of 0.33% fish oil, 0.67% fish oil, and 1% fish oil with extruded soybeans providing the balance of added fat. Dry matter intake (23.1, 22.6, 22.8, and 22.9 kg/d, for control, low, medium, and high fish oil diets, respectively) was similar for all diets. Milk production (21.5, 23.7, 22.7, and 24.2 kg/d) was higher for cows fed the fat-supplemented diets vs. the control. Milk fat (4.42, 3.81, 3.80, and 4.03%) and true protein (3.71, 3.58, 3.54, and 3.55%) concentrations decreased when cows were fed diets containing supplemental fat. Concentration of milk cis-9,trans-11 CLA (0.55, 1.17, 1.03, and 1.19 g/100 g of fatty acids) was increased similarly by all diets containing supplemental fat. Milk VA (1.12, 2.47, 2.13, and 2.63 g/100 g of fatty acids) was increased most in milk from cows fed the low and high fish oil diets. Milk total n-3 fatty acids were increased (0.82, 0.96, 0.92, and 1.01 g/100 g of fatty acids) by all fat-supplemented diets. The low fish oil diet was as effective at increasing VA and CLA in milk as the high fish oil diet, showing that only low concentrations of dietary fish oil are necessary for increasing concentrations of VA and CLA in milk.

Determination of vitamin B12 in dry feeds by atomic absorption spectrophotometry.

Vitamin B12 was determined in dry feeds by atomic absorption spectrophotometry (AAS). Samples containing B12 were extracted with an assay solution, 5 g EDTA was added to the filtrate, the pH was adjusted to 7 with NH4OH, and 5 g charcoal was added. The charcoal was removed by filtering through ashless paper which was then placed in a beaker and ashed at 600 degrees C. After dissolving the cobalt oxide from the ash in 5N HNO3, cobalt content was determined by using AAS. To determine mg B12/lb feed, ppm cobalt in the feed is multiplied by 10.43. The sensitivity of the proposed procedure is 1 mg vitamin B12/lb. The procedure is rapid and precise, and results compare favorably with AOAC method 43.109.

Feeding fish meal and extruded soybeans enhances the conjugated linoleic acid (CLA) content of milk.

Twelve multiparous Holstein cows averaging 65 (33 to 122) DIM were used in a 4 x 4 Latin square for 4-wk periods to determine whether feeding fish oil as fish meal would stimulate increased amounts of milk conjugated linoleic acid (cis-9, trans-11 C18:2; CLA) and transvaccenic acid (trans-11 C18:1; TVA) when the cows were fed extruded soybeans to supply additional linoleic acid. Treatment diets were 1) control; 2) 0.5% fish oil from fish meal; 3) 2.5% soybean oil from extruded soybeans; and 4) 0.5% fish oil from fish meal and 2% soybean oil from extruded soybeans. Diets were formulated to contain 18% crude protein and were composed (dry basis) of 50% concentrate mix, 25% corn silage, and 25% alfalfa hay. Intake of DM was not affected by diet. Milk production was increased by diets 2, 3, and 4 compared with diet 1 (control). Milk fat and milk protein percentages decreased with diets 3 and 4. Milk fat yield was not affected by treatments, but yield of milk protein was increased with supplemental fish meal and extruded soybeans or their blend. When diets 2, 3, or 4 were fed, concentrations of cis-9, trans-11 CLA in milk fat increased by 0.4-, 1.4-, and 3.2-fold, and TVA concentrations in milk fat increased by 0.4-, 1.8-, and 3.5-fold compared with the control milk fat. Increases in TVA and cis-9, trans-11 CLA were 91 to 109% greater when a blend of fish meal and extruded soybeans was fed than the additive effect of fish meal and extruded soybeans. This suggested that fish oil increased the production of CLA and TVA from other dietary sources of linoleic acid such as extruded soybeans.

Short communication: Consumer evaluation of milk high in conjugated linoleic acid.

A consumer evaluation was undertaken to determine whether there were differences in the acceptability of milk from cows fed a control or a fish oil diet. The two treatments included a control diet of a 50:50 ratio of forage-to-concentrate and fish oil added to the control diet with 2% (on dry matter basis) added fat from menhaden fish oil. Milk from cows fed the control or fish oil diet contained 3.31 and 2.58% fat and 0.56 and 2.30 g of total conjugated linoleic acid/100 g of fatty acids, respectively. Consumer evaluation of control and fish oil milks found no difference in acceptability.

Milk production and composition from cows fed high oil or conventional corn at two forage concentrations.

Twelve multiparous Holstein cows (63 +/- 24 d in milk) were used in a replicated 4 x 4 Latin square with 28-d periods to evaluate conventional and high oil corn grains when fed at two different forage-to-concentrate ratios. Dietary treatments consisted of conventional or high oil corn supplementing a diet with a 25:25:50 mixture of corn silage: alfalfa: concentrate mix, or a high forage diet with a 30:30:40 mixture of corn silage: alfalfa: concentrate mix. Dry matter intake (28.1, 28.7, 26.9, and 26.2 kg/d for normal diets with conventional and high oil corn, and high forage diets with conventional and high oil corn, respectively) and milk yields (36.8, 37.2, 35.5, and 35.2 kg/d) were similar for conventional and high oil corn diets and were lower with the high forage diet, regardless of corn source. Milk fat concentrations were greater when cows were fed diets containing 60% forage (4.03 vs. 3.88%, for the 60 and 50% forages, respectively), but milk protein concentrations were not affected by forage content. Corn source did not affect milk fat or protein concentrations. Long-chain fatty acid concentrations, unsaturated fatty acid concentrations, and total 18:1 fatty acid concentrations were greater when cows were fed high oil corn but were unaffected by forage content of the diet. Concentrations of transvaccenic acid (0.58, 0.81, 0.62, and 0.69 g/100 g of fatty acids) and cis-9, trans-11 conjugated linoleic acid (0.28, 0.39, 0.32, and 0.33 g/100 g of fatty acids) were greater when cows were fed high oil compared with conventional corn when fed 50% forage but were similar for both corn sources at 60% forage. Total n-3 fatty acids were not affected by corn source or forage content. High forage diets decreased milk production and increased milk fat concentration. Feeding high oil corn increased concentrations of long-chain, unsaturated, transvaccenic, and conjugated linoleic fatty acids in milk; however, production of transvaccenic and conjugated linoleic acids were attenuated by high forage diet.

Fatty acid profiles of milk and rumen digesta from cows fed fish oil, extruded soybeans or their blend.

Four fistulated primiparous cows (two Holstein and two Brown Swiss) averaging 102 DIM were used in a 4 x 4 Latin square with 3-wk periods to determine the effect of feeding fish oil, extruded soybeans, or their combination on fatty acid profiles of milk and rumen digesta. Experimental diets consisted of: 1) control diet; 2) a diet with 2% (DM basis) added fat from menhaden fish oil; 3) a diet with 2% added fat from extruded soybeans; and 4) a diet with 1% added fat from fish oil and 1% fat from extruded soybeans. All diets consisted of 25% corn silage, 25% alfalfa hay, and 50% concentrate. Milk yields (28.6, 29.7, 29.2, and 28.1 kg/d for control, fish oil, extruded soybeans, and combination diets, respectively) were similar for all fat supplements and control. Milk fat and protein percentages (3.49, 3.08; 3.25, 2.96; 3.47, 3.01; 3.48, 2.99 for diets 1, 2, 3, and 4, respectively) were not affected by fat supplements compared with control. Dry matter intake (23.0, 21.6, 22.7, and 21.6 kg/d) was reduced when diets containing fish oil were fed. Concentrations of conjugated linoleic acid [CLA; cis-9, trans-11 CLA, 0.40, 0.88, 0.87, and 0.80 g/100 g fatty acids (FA)] and transvaccenic acid (TVA, 1.02, 2.34, 2.41, and 2.06 g/100 g of FA) were increased in milk fat by all fat supplements, with no differences in milk CLA and TVA observed among fat supplements. As with milk fat, proportions of ruminal CLA (0.09, 0.26, 0.18, and 0.21 g/100 g of FA) and TVA (2.61, 4.56, 4.61, and 4.39 g/100 g of FA) increased with fat supplements. The effects of fat supplements on ruminal TVA and CLA concentrations were also reflected in rumen FA-salts, free fatty acids, and neutral lipids. The higher TVA to CLA ratio in the rumen compared with milk indicated that fat supplements increased milk CLA concentration mainly by increasing ruminal production of TVA, which also implied the significant role that mammary delta-9 desaturase plays in milk CLA concentrations.

Composition and flavor of milk and butter from cows fed fish oil, extruded soybeans, or their combination.

Milk was collected from eight multiparous Holstein and four multiparous Brown Swiss cows that were distributed into four groups and arranged in a randomized complete block design with four 4-wk periods. The four treatments included a control diet of a 50:50 ratio of forage-to-concentrate; a fish oil diet of the control diet with 2% (on dry matter basis) added fat from menhaden fish oil; a fish oil with extruded soybean diet of the control diet with 1% (on dry matter basis) added fat from menhaden fish oil and 1% (on dry matter basis) added fat from extruded soybeans; and an extruded soybean diet of the control diet with 2% (on dry matter basis) added fat from extruded soybeans. Milk from cows fed control, fish oil, fish oil with extruded soybean, and extruded soybean diets contained 3.31, 2.58, 2.94, and 3.47% fat, respectively. Concentrations of conjugated linoleic acid in milk were highest in the fish oil (2.30 g/100 g of fatty acids) and fish oil with extruded soybean (2.17 g/100 g of fatty acids) diets compared with the control (0.56 g/100 g fatty acids) diet. Milk, cream, butter, and buttermilk from the fish oil, fish oil with extruded soybean, and extruded soybean diets had higher concentrations of transvaccenic acid and unsaturated fatty acids compared with the controls. Butter made from the extruded soybean diet was softest compared with all treatments. An experienced sensory panel found no flavor differences in milks or butters.

Fish oil and extruded soybeans fed in combination increase conjugated linoleic acids in milk of dairy cows more than when fed separately.

Eight multiparous Holstein and four multiparous Brown Swiss (78 +/- 43 DIM) cows were used in a 4 x 4 Latin square with 28-d periods to evaluate if feeding fish oil with a source of linoleic acid (extruded soybeans) would stimulate additional amounts of conjugated linoleic acid in milk. Four treatments consisted of a control diet with a 50:50 ratio of forage to concentrate (DM basis), a control diet with 2% added fat from either menhaden fish oil or extruded soybeans, or a combination of fish oil and extruded soybeans each adding 1% fat. DM intake (24.3, 21.6, 24.5, and 22.5 kg/d, for control, fish oil, extruded soybeans, and combination diets, respectively), milk production (32.1, 29.1,34.6, and 31.1 kg/d), and milk fat content (3.51, 2.79, 3.27, and 3.14%) were lower for cows that consumed either fish oil-containing diet, especially the 2% fish oil diet. The proportion of n-3 fatty acids in milk fat increased similarly among all three fat-supplemented diets. Concentrations of transvaccenic acid (1.00, 4.16, 2.17, and 3.51 g/100 g of fatty acids) and cis-9, trans-11 conjugated linoleic acid (0.60, 2.03, 1.16, and 1.82 g/100 g of fatty acids) in milk fat increased more with fish oil than with extruded soybeans. When fed the combination diet, these fatty acids were approximately 50% higher than expected for Holsteins, whereas concentrations were similar for Brown Swiss compared with feeding each fat source separately. These data indicated that fish oil modifies ruminal or systemic functions, stimulating increased conversion of linoleic acid into transvaccenic and conjugated linoleic acids.