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Porcine epidemic diarrhea virus (PEDV) emerged in the United States (U.S.) swine population in 2013, initiating an initial significant epidemic followed by a state of endemicity in the U.S. Despite continued monitoring, the epidemiology of PEDV during its endemic phase remains inadequately researched. Our study aimed to characterize the spatial–temporal distribution of postepidemic PEDV cases in the U.S. breeding herd and identify associated risk factors. Data from 1089 breeding farms in 27 states, reported to the Morrison Swine Health Monitoring Project from July 2014 to June 2021, were analyzed. We stratified the data into six U.S. regions and employed SaTScan for spatiotemporal permutation and cluster analysis. Survival analysis was used to assess risk factors. A notable seasonal clustering of PEDV cases was observed in winter (January–March; p = 0.001, relative risk = 2.2) with regional variation. Ten high‐rate spatial–temporal clusters (p < 0.05) were identified ranging from 2.5 to 833.7 km2 and lasting 1–5 months, occurring in four regions between 2015 and 2021. For the study period, a total of 625 cases of PEDV were recorded on 372 farms. The total number of PEDV cases decreased from 95 breeding farms in 32 counties (2014–2015) to 53 farms in 28 counties (2020–2021), indicating an overall reduction in occurrence and spatial extent. Feed mitigants demonstrated a protective effect, significantly reducing the risk of PEDV occurrence (hazard ratio = 0.3, p = 0.003), while air filtration systems exhibited marginal benefits (hazard ratio = 0.3, p = 0.06). Other important risk factors included county farm density with farms in high‐density regions (>31 farms/100 km2) being 1.3 times more likely to experience outbreaks than in medium‐density regions (13–31 farms/1000 km2; p < 0.001). Additionally, farms in region E had higher odds of outbreaks compared to region B. The overall decline in PEDV cases and reduced spatial extent reflect industry efforts in postepidemic control and elimination. The protective effects of feed mitigants warrant further investigation. Our findings underscore the opportunity for coordinated efforts to eliminate PEDV in the U.S. and emphasize the need for comprehensive risk profiling associated with industry practices. [ABSTRACT FROM AUTHOR]

Bovine tuberculosis (bTB) prevalence substantially increased over the past two decades with relatively high impact on large dairy herds, raising the concern of regulatory authorities and industry stakeholders, and threatening animal and public health. Lack of resources, together with the economic and social consequences of whole‐herd stamping‐out, makes depopulation an impractical disease control alternative in these herds. The increase in bTB prevalence was associated with demographic and management changes in the dairy industry in Uruguay, reducing the efficacy of the current control programme (i.e. status quo) based on intradermal serial testing with caudal fold‐ and comparative‐cervical tuberculin test‐and‐slaughter of reactors (CFT‐CCT). Here, we aimed to assess the epidemiological effectiveness of six alternative control scenarios based on test‐and‐slaughter of positive animals, using mathematical modelling to infer bTB‐within‐herd dynamics. We simulated six alternative control strategies consisting of testing adult cattle (>1 year) in the herd every 3 months using one test (in vivo or in vitro) or a combination in parallel of two tests (CFT, interferon‐gamma release assay—IGRA‐ or enzyme‐linked immunosorbent assay). Results showed no significant differences overall in the time needed to reach bTB eradication (median ranging between 61 and 82 months) or official bovine tuberculosis‐free status (two consecutive negative herd tests) between any of the alternative strategies and the status quo (median ranging between 50 and 59 months). However, we demonstrate how alternative strategies can significantly reduce bTB prevalence when applied for restricted periods (6, 12 or 24 months), and in the case of IGRAc (IGRA using peptide‐cocktail antigens), without incurring on higher unnecessary slaughter of animals (false positives) than the status quo in the first 6 months of the programme (p‐value <.05). Enhanced understanding bTB‐within‐herd dynamics with the application of different control strategies help to identify optimal strategies to ultimately improve bTB control and bTB eradication from dairies in Uruguay and similar endemic settings. [ABSTRACT FROM AUTHOR]

On March 24, 2024, the US Department of Agriculture (USDA) confirmed the first case of highly pathogenic avian influenza (HPAI) H5N1 clade 2.3.4.4b in dairy cattle. Following this initial detection, the virus was found to have spread to other species, including humans. Since then, at least 192 dairy herds across 13 states have tested positive for the virus. The emergence of HPAI H5N1 in dairy cattle poses a serious threat to the dairy industry, requiring an approach that integrates human, animal, and environmental health. Enhancing biosecurity, improving surveillance, and advancing research are critical to managing this challenge. Swift adaptation is needed to protect both public health and dairy production. Through this work, we discuss the epidemiological and clinical aspects of HPAI H5N1 in cattle by reviewing the spatiotemporal situation of the disease across the United States, the clinical signs and testing leading to a confirmed case, and the surveillance and control measures implemented at the national and state levels. Further, considering pathogenesis and risk factors, we discuss surveillance and control measures to implement within herds, and note areas where research is needed to understand how to control this emerging disease., (© 2024.)