Evidence for Human Adaptation and Foodborne Transmission of Livestock-Associated Methicillin-Resistant Staphylococcus aureus
- Clinical infectious diseases : an official publication of the Infectious Diseases Society of America
- Published 12 months ago
We investigated the evolution and epidemiology of a novel livestock-associated methicillin-resistant Staphylococcus aureus strain, which colonizes and infects urban-dwelling Danes even without a Danish animal reservoir. Genetic evidence suggests both poultry and human adaptation, with poultry meat implicated as a probable source.
Microbial communities associated with agricultural animals are important for animal health, food safety, and public health. Here we combine high-throughput sequencing (HTS), quantitative-PCR assays, and network analysis to profile the poultry-associated microbiome and important pathogens at various stages of commercial poultry production from the farm to the consumer. Analysis of longitudinal data following two flocks from the farm through processing showed a core microbiome containing multiple sequence types most closely related to genera known to be pathogenic for animals and/or humans, including , and . After the final stage of commercial poultry processing, taxonomic richness was ca. 2-4 times lower than the richness of fecal samples from the same flocks and abundance was significantly reduced. Interestingly, however, carcasses sampled at 48 hr after processing harboured the greatest proportion of unique taxa (those not encountered in other samples), significantly more than expected by chance. Among these were anaerobes such as , , , and multiple sequence types. Retail products were dominated by , but also contained 27 other genera, most of which were potentially metabolically active and encountered in on-farm samples. Network analysis was focused on the foodborne pathogen and revealed a majority of sequence types with no significant interactions with other taxa, perhaps explaining the limited efficacy of previous attempts at competitive exclusion of . These data represent the first use of HTS to characterize the poultry microbiome across a series of farm-to-fork samples and demonstrate the utility of HTS in monitoring the food supply chain and identifying sources of potential zoonoses and interactions among taxa in complex communities.
Evaluation of poultry protein isolate (PPI) as a food ingredient was carried out by substituting nonmeat ingredients such as soy protein isolate (SPI) or meat protein in turkey bologna. Two concentrations (1.5 and 2% dry weight basis) of PPI prepared from mechanically separated turkey meat were used in this study. Two control samples were prepared with 11 and 13% meat protein, respectively. Physicochemical characteristics of turkey bologna containing PPI were compared with those of control and SPI-containing samples. Batter strength was higher for 2% PPI and 13% meat protein control samples (control-2) compared with all other treatments. Cooking yield of the 11% meat protein control was significantly (P < 0.05) less compared with other treatments. However, there was no significant difference in the expressible moisture or purge loss among all the treatments. Control-2 showed lower L* values and was more reddish during refrigerated storage. Addition of protein isolates caused a significant increase (b* value varied between 11.48 and 12.52) in yellowness of products. Turkey bologna with added protein isolates showed significantly lower lipid oxidation as indicated by induced TBA reactive substance analysis. Results from this study suggest that SPI or meat protein could be replaced by PPI without negatively affecting product characteristics as evident from cooking yield and purge loss values.
Avian influenza viruses affect both poultry production and public health. A subtype H5N8 (clade 220.127.116.11) virus, following an outbreak in poultry in South Korea in January 2014, rapidly spread worldwide in 2014-2015. Our analysis of H5N8 viral sequences, epidemiological investigations, waterfowl migration, and poultry trade showed that long-distance migratory birds can play a major role in the global spread of avian influenza viruses. Further, we found that the hemagglutinin of clade 18.104.22.168 virus was remarkably promiscuous, creating reassortants with multiple neuraminidase subtypes. Improving our understanding of the circumpolar circulation of avian influenza viruses in migratory waterfowl will help to provide early warning of threats from avian influenza to poultry, and potentially human, health.
Objective To determine the association of different types of meat intake and meat associated compounds with overall and cause specific mortality.Design Population based cohort study.Setting Baseline dietary data of the NIH-AARP Diet and Health Study (prospective cohort of the general population from six states and two metropolitan areas in the US) and 16 year follow-up data until 31 December 2011.Participants 536 969 AARP members aged 50-71 at baseline.Exposures Intake of total meat, processed and unprocessed red meat (beef, lamb, and pork) and white meat (poultry and fish), heme iron, and nitrate/nitrite from processed meat based on dietary questionnaire. Adjusted Cox proportional hazards regression models were used with the lowest fifth of calorie adjusted intakes as reference categories.Main outcome measure Mortality from any cause during follow-up.Results An increased risk of all cause mortality (hazard ratio for highest versus lowest fifth 1.26, 95% confidence interval 1.23 to 1.29) and death due to nine different causes associated with red meat intake was observed. Both processed and unprocessed red meat intakes were associated with all cause and cause specific mortality. Heme iron and processed meat nitrate/nitrite were independently associated with increased risk of all cause and cause specific mortality. Mediation models estimated that the increased mortality associated with processed red meat was influenced by nitrate intake (37.0-72.0%) and to a lesser degree by heme iron (20.9-24.1%). When the total meat intake was constant, the highest fifth of white meat intake was associated with a 25% reduction in risk of all cause mortality compared with the lowest intake level. Almost all causes of death showed an inverse association with white meat intake.Conclusions The results show increased risks of all cause mortality and death due to nine different causes associated with both processed and unprocessed red meat, accounted for, in part, by heme iron and nitrate/nitrite from processed meat. They also show reduced risks associated with substituting white meat, particularly unprocessed white meat.
Prevalence of ASD seems to have increase in recent decades. There have been many attempts to find the responsible agent at various levels, from genetics to environmental factors. In this paper we draw attention to the possibility that one of the hidden agents spurring the rise in autism prevalence is to be identified within the industrial system of food production, particularly meat production with special emphasis on poultry meat. The paper presents some exploratory analyses demonstrating the correlation between particular aspects of meat consumption and autism prevalence. This initial exploration has lead to the hypothesis that industrial meat production - especially of poultry meat - may involve significant risk factors requiring thorough investigation. The main suspects seem to be hormonal and other growth-promoting agents.
Since the first description of a plasmid-mediated colistin resistance gene (mcr-1) in November 2015 multiple reports of mcr-1 positive isolates indicate a worldwide spread of this newly discovered resistance gene in Enterobacteriaceae. Although the occurrence of mcr-1 positive isolates of livestock, food, environment and human origin is well documented only few systematic studies on the prevalence of mcr-1 are available yet. Here, comprehensive data on the prevalence of mcr-1 in German livestock and food isolates are presented. Over 10.600 E. coli isolates from the national monitoring on zoonotic agents from the years 2010-2015 were screened for phenotypic colistin resistance (MIC value >2 mg/l). Of those, 505 resistant isolates were screened with a newly developed TaqMan-based real-time PCR for the presence of the mcr-1 gene. In total 402 isolates (79.8% of colistin resistant isolates) harboured the mcr-1 gene. The prevalence was depending on the food production chain. The highest prevalence was detected in the turkey food chain (10.7%), followed by broilers (5.6%). A low prevalence was determined in pigs, veal calves and laying hens. The mcr-1 was not detected in beef cattle, beef and dairy products in all years investigated. In conclusion, TaqMan based real-time PCR provides a fast and accurate tool for detection of mcr-1 gene. The overall detection rate of 3.8% for mcr-1 among all E. coli isolates tested is due to high prevalence of mcr-1 in poultry production chains. More epidemiological studies of other European countries are urgently needed to assess German prevalence data.
Previous research conducted in 2009 found a significant positive association between pneumonia in humans and living close to goat and poultry farms. However, as this result might have been affected by a large goat-related Q fever epidemic, the aim of the current study was to re-evaluate this association, now that the Q-fever epidemic had ended. In 2014/15, 2,494 adults (aged 20-72 years) living in a livestock-dense area in the Netherlands participated in a medical examination and completed a questionnaire on respiratory health, lifestyle and other items. We retrieved additional information for 2,426/2,494 (97%) participants from electronic medical records (EMR) from general practitioners. The outcome was self-reported, physician-diagnosed pneumonia or pneumonia recorded in the EMR in the previous three years. Livestock license data was used to determine exposure to livestock. We quantified associations between livestock exposures and pneumonia using odds ratios adjusted for participant characteristics and comorbidities (aOR). The three-year cumulative frequency of pneumonia was 186/2,426 (7.7%). Residents within 2,000m of a farm with at least 50 goats had an increased risk of pneumonia, which increased the closer they lived to the farm (2,000m aOR 1.9, 95% CI 1.4-2.6; 500m aOR 4.4, 95% CI 2.0-9.8). We found no significant associations between exposure to other farm animals and pneumonia. However, when conducting sensitivity analyses using pneumonia outcome based on EMR only, we found a weak but statistically significant association with presence of a poultry farm within 1,000m (aOR: 1.7, 95% CI 1.1-2.7). Living close to goat and poultry farms still constitute risk factors for pneumonia. Individuals with pneumonia were not more often seropositive for Coxiella burnetii, indicating that results are not explained by Q fever. We strongly recommend identification of pneumonia causes by the use of molecular diagnostics and investigating the role of non-infectious agents such as particulate matter or endotoxins.
Next Generation Sequencing for the investigation of an Outbreak of Salmonella Schwarzengrund in Nanjing, China
- International journal of biological macromolecules
- Published 10 days ago
Salmonella Schwarzengrund is most frequently isolated from poultry meat and can cause human infections. S. Schwarzengrund was isolated from diarrheal patients in a food poisoning event in Nanjing, China.
This review presents up-to-date information about current research on nicarbazin, one of the most used anticoccidials in poultry production. The focus is to elucidate regulation concerning nicarbazin, limits for its residues in food, how maximum residue limits in different countries are calculated regarding edible chicken tissues and the possible implications in human health. Analytical methods to extract and quantify this residue, expressed as dinitrocarbanilide (DNC) are presented and discussed, including qualitative screening and quantitative/confirmatory analytical methods. Monitoring results and occurrence of DNC residues in chicken meat are discussed. Additionally, the causes of eventual chicken meat contamination and possible solutions to reduce or eliminate DNC residue in tissues are also presented. The paper concludes with perspectives, the current state of DNC residue analysis and suggestions for future research, especially considering the gap in the study of residue recycling effect due to continuous chicken litter use.