Quantitative Risk Assessment of Antimicrobial-Resistant Foodborne Infections in Humans Due to Recombinant Bovine Somatotropin Usage in Dairy Cows

Abstract

Recombinant bovine somatotropin (rbST) is a production-enhancing technology that allows the dairy industry to produce milk more efficiently. Concern has been raised that cows supplemented with rbST are at an increased risk of developing clinical mastitis, which would potentially increase the use of antimicrobial agents and increase human illnesses associated with antimicrobial-resistant bacterial pathogens delivered through the dairy beef supply. The purpose of this study was to conduct a quantitative risk assessment to estimate the potential increased risk of human infection with antimicrobial-resistant bacteria and subsequent adverse health outcomes as a result of rbST usage in dairy cattle. The quantitative risk assessment included the following steps: (i) release of antimicrobial-resistant organisms from the farm, (ii) exposure of humans via consumption of contaminated beef products, and (iii) consequence of the antimicrobial-resistant infection. The model focused on ceftiofur (parenteral and intramammary) and oxytetracycline (parenteral) treatment of clinical mastitis in dairy cattle and tracked the bacteria Campylobacter spp., Salmonella enterica subsp. enterica, and Escherichia coli in the gastrointestinal tract of the cow. Parameter estimates were developed to be maximum risk to overestimate the risk to humans. The excess number of cows in the U.S. dairy herd that were predicted to carry resistant bacteria at slaughter due to rbST administration was negligible. The total number of excess human illnesses caused by resistant bacteria due to rbST administration was also predicted to be negligible with all risks considerably less than one event per 1 billion people at risk per year for all bacteria. The results indicate a high probability that the use of rbST according to label instructions presents a negligible risk for increasing the number of human illnesses and subsequent adverse outcomes associated with antimicrobial-resistant Campylobacter, Salmonella, or E. coli .

Target analysis and retrospective screening of mycotoxins and pharmacologically active substances in milk using an ultra-high-performance liquid chromatography/high-resolution mass spectrometry approach

“…However, inappropriate use of pharmacologically active substances, or lack of respect for the withdrawal period, can lead to residues in animal-derived products, such as milk. In this way, pharmacologically active substances may enter the food chain and human exposure can induce acute poisoning, allergic reactions, or antibiotic resistance (Singer et al, 2017). Based on sales data published by the Ministry of Health, updated to 2016, the most commonly used veterinary drugs in Italy were penicillins, tetracyclines, and sulfonamides, which together represented 68.7% of total sales in 2016 (Ministero della salute, 2016).…”

Quantitative Microbial Risk Assessment and Infectious Disease Transmission Modeling of Waterborne Enteric Pathogens

“…Contamination sources may be wastewater irrigation, food handlers, etc. Foodstuffs of concern were primarily related to animal products—pork [35, 81, 114–117], beef [118–121], chicken [79, 122–125], shellfish [37, 126], and eggs and dairy [127–133]—but contaminated vegetable crops, such as nuts [33, 34, 134] and greens [29, 58, 61, 63, 135–137] were also studied. The pathogens most often investigated in food-related transmission context were Salmonella (N=8), Campylobacter (N=7), and E. coli (N=6).…”