To establish a possible role for the natural environment in the transmission of clinically relevant AMR bacteria to humans, a literature review was conducted to systematically collect and categorize evidence for human exposure to extended-spectrum β-lactamase-producing Enterobacteriaceae, methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus spp. in the environment. In total, 239 datasets adhered to inclusion criteria. AMR bacteria were detected at exposure-relevant sites (35/38), including recreational areas, drinking water, ambient air, and shellfish, and in fresh produce (8/16). More datasets were available for environmental compartments (139/157), including wildlife, water, soil, and air/dust. Quantitative data from exposure-relevant sites (6/35) and environmental compartments (11/139) were scarce. AMR bacteria were detected in the contamination sources (66/66) wastewater and manure, and molecular data supporting their transmission from wastewater to the environment (1/66) were found. The abundance of AMR bacteria at exposure-relevant sites suggests risk for human exposure. Of publications pertaining to both environmental and human isolates, however, only one compared isolates from samples that had a clear spatial and temporal relationship, and no direct evidence was found for transmission to humans through the environment. To what extent the environment, compared to the clinical and veterinary domains, contributes to human exposure needs to be quantified. AMR bacteria in the environment, including sites relevant for human exposure, originate from contamination sources. Intervention strategies targeted at these sources could therefore limit emission of AMR bacteria to the environment.
A full history of the management practices and the prevalence of upper respiratory tract disease (URTD) at 218 rescue shelters, breeding establishments and private households with five or more cats was recorded. Oropharyngeal and conjunctival swabs and blood samples were taken from 1748 cats. The prevalences of feline herpesvirus (FHV), feline calicivirus (FCV), Chlamydophila felis and Bordetella bronchiseptica were determined by PCR on swab samples. An ELISA was applied to determine the prevalence of antibodies to B bronchiseptica. The rates of detection by PCR of each pathogen in the cats in catteries with and without ongoing URTD were, respectively, FHV 16 per cent and 8 per cent; FCV 47 per cent and 29 per cent; C felis 10 per cent and 3 per cent; and B bronchiseptica 5 per cent and 1·3 per cent; the seroprevalences of B bronchiseptica were 61 per cent and 41 per cent, respectively. There was evidence that FHV, FCV and B bronchiseptica played a role in URTD. The risk factors associated with the disease were less than excellent hygiene, contact with dogs with URTD, and larger numbers of cats in the cattery or household.
SUMMARYTo determine methicillin-resistant Staphylococcus aureus (MRSA) carriage in poultry and slaughterhouse personnel, 40 Dutch broiler flocks, in six slaughterhouses and 466 personnel were sampled. Of the employees, 26 were positive (5 . 6 %), indicating a higher risk of exposure when compared to the general Dutch population (0 . 1 %). This risk was significantly higher for personnel having contact with live animals (5 . 2 %) -especially hanging broilers on the slaughterline (20 . 0%) -than for all other personnel (1 . 9 %). Conventional electric stunning conferred a significantly higher risk of MRSA carriage for employees than CO 2 stunning (9 . 7% vs. 2 . 0%). A total of 405 broilers were sampled upon their arrival at the slaughterhouse, of which 6 . 9% were positive. These broilers originated from 40 Dutch slaughter flocks of which 35 . 0% were positive. MRSA contamination in the different compartments of slaughterhouses increased during the production day, from 8 % to 35 %. Of the 119 MRSA isolates, predominantly livestock-associated MRSA ST398 was found, although 27 . 7 % belonged to ST9 (spa type t1430). There is an increased risk of MRSA carriage in personnel working at broiler slaughterhouses, particularly those having contact with live animals.
The prevalence among people on broiler farms was higher than in previous studies involving patients and the general population. Furthermore, an increased risk of carriage was shown among individuals having a high degree of contact with live broilers. The (relative) contribution of transmission routes that might play a role in the dissemination of ESBL/AmpC-encoding resistance genes to humans on broiler farms should be pursued in future studies.
Egg storage longer than 7 d is associated with a delay in hatch time and a decline in hatchability and chick quality. Prestorage incubation is suggested as a method to reduce the negative effects of prolonged storage times by altering the developmental stage of the embryo, but earlier research has shown that prestorage incubation can both be detrimental and beneficial for hatchability. The reason for these ambiguous results is not clear and the effect of prestorage incubation on chick quality is not studied extensively. The objective of this study was to investigate changes in developmental stage of embryos during prestorage incubation and the effect of prestorage incubation on hatchability and chick quality. Two experiments were conducted. In experiment I, eggs were stored for 3, 5, 8, or 12 d. In experiment II, eggs were stored for 5 or 11 d. Half of the eggs was stored immediately at 16 to 18 degrees C and the other half was exposed to prestorage incubation for 6 h in experiment I and for 4.5 h in experiment II. According to the classification table of Eyal-Giladi and Kochav (EG), embryonic development was advanced by prestorage incubation from developmental stage EG11.67 to developmental stage EG13.26 in experiment I (P = 0.02) and from developmental stage EG9.22 to developmental stage EG12.63 in experiment II (P< 0.0001). In experiment I, prestorage incubation reduced hatchability of set eggs from 59.3 to 51.5% when storage time was 12 d but did not reduce hatchability when storage time was 3, 5, or 8 d (interaction P = 0.02). Prestorage incubation increased chick length (P = 0.004). In experiment II, prestorage incubation increased hatchability of fertile eggs from 80.6 to 85.9% when storage time was 11 d but did not increase hatchability when storage time was 5 d (interaction P = 0.0009). Prestorage incubation increased percentage of second grade chicks (P = 0.0007). It seems that storage time, embryonic development at egg collection, and prestorage incubation duration determine the effect of prestorage incubation on hatchability and chick quality.
The objective of this study was to evaluate Fourier transform infrared (FTIR) spectrometry to measure milk ketone bodies to detect hyperketonemic cows and compare this method with milk fat to protein ratio to detect hyperketonemia. Plasma and milk samples were obtained weekly from calving to wk 9 postpartum from 69 high-producing dairy cows. The reference test for hyperketonemia was defined as plasma concentration of β-hydroxybutyrate (BHBA) ≥1,200 μmol/L. The weekly prevalence of hyperketonemia during the first 9 wk of lactation was, on average, 7.1%. Both BHBA and acetone in milk, determined by FTIR, had a higher sensitivity (80%) to detect hyperketonemia compared with milk fat to protein ratio (66%). Specificity was similar for the 3 diagnostic tests (71, 70, and 71%). In conclusion, FTIR predictions of BHBA or acetone in milk can detect cows with hyperketonemia in early lactation with a higher accuracy compared with the use of milk fat to protein ratio. Because of the high proportion of false-positive tests, there are concerns about the practical applicability of FTIR predictions of acetone, BHBA, and fat to protein ratio in milk to detect hyperketonemic cows.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.