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Poultry contact is a risk factor for zoonotic transmission of non-typhoidal Salmonella spp. Salmonella illness outbreaks in the United States are identified by PulseNet, the national laboratory network for enteric disease surveillance. During 2020, PulseNet observed a 25% decline in the number of Salmonella clinical isolates uploaded by state and local health departments. However, 1722 outbreak-associated Salmonella illnesses resulting from 12 Salmonella serotypes were linked to contact with privately owned poultry, an increase from all previous years. This report highlights the need for continued efforts to prevent backyard poultry-associated outbreaks of Salmonella as ownership increases in the United States.

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In December 2018, PulseNet, the national laboratory network for enteric disease surveillance, identified an increase in Salmonella Typhimurium isolates with an uncommon pulsed‐field gel electrophoresis pattern which was previously isolated from hedgehogs. CDC, state, and local health partners interviewed patients with a questionnaire that focused on hedgehog exposures, conducted traceback of patients' hedgehog purchases, and collected hedgehog faecal pellets and environmental samples. Isolates in this outbreak were analysed using core‐genome multi‐locus sequence typing (cgMLST) and compared to sequence data from historic clinical isolates from a 2011–2013 outbreak of Salmonella Typhimurium illnesses linked to pet hedgehogs. Fifty‐four illnesses in 23 states were identified between October 2018 and September 2019. Patients ranged from <1 to 95 years, and 65% were female. Eight patients were hospitalized. Eighty‐one per cent (29/36) of patients interviewed reported contact with a hedgehog before becoming ill; of these, 21 (72%) reported owning a hedgehog. Analysis of 53 clinical, 11 hedgehog, and two hedgehog bedding isolates from this outbreak, seven hedgehog isolates obtained prior to this outbreak, and two clinical isolates from the 2011–2013 outbreak fell into three distinct groupings (37 isolates in Clade 1 [0–10 alleles], 28 isolates in Clade 2 [0–7 alleles], and eight isolates in Clade 3 [0–12 alleles]) and were collectively related within 0–31 alleles by cgMLST. Purchase information available from 20 patients showed hedgehogs were purchased from multiple breeders across nine states, a pet store, and through an online social media website; a single source of hedgehogs was not identified. This outbreak highlights the ability of genetic sequencing analysis to link historic and ongoing Salmonella illness outbreaks and demonstrates the strain of Salmonella linked to hedgehogs might continue to be a health risk to hedgehog owners unless measures are taken to prevent transmission.

Successful conservation efforts for threatened species depend on accurate characterization of their distribution, habitat use, and threats. However, surveillance can be challenging for species with small size, cryptic coloring, or elusive behavior.Environmental DNA (eDNA) monitoring can provide a sensitive and noninvasive alternative to traditional surveillance techniques by detecting trace DNA shed by a target species into their environment. We evaluated the efficacy of eDNA monitoring for the four-toed salamander (Hemidactylium scutatum), a terrestrial salamander threatened throughout much of its range. Additionally, we integrated eDNA monitoring for ranavirus, a widespread pathogen of ectothermic vertebrates, to efficiently evaluate a potential disease threat to H. scutatum. We designed a novel species-specific quantitative PCR (qPCR) assay for H. scutatum, multiplexed the assay with a previously developed ranavirus qPCR assay, and validated the multiplexed tests in silico, in vitro, and in situ. We collected aquatic eDNA weekly for 8 weeks from pools with historical reports of H. scutatum (n = 6) and contemporary reports of H. scutatum on associated uplands (n = 4). We identified H. scutatum eDNA at low quantities (< 12 copies/reaction) on multiple sampling days in two pools with historic species presence.Ranavirus eDNA was widespread; nine pools tested positive including the pools where H. scutatum eDNA was detected. Ranavirus eDNA quantities increased, peaked, then decreased (i.e., were not sporadic in time) in several pools but never rose in abundance to levels associated with ranavirosis in other studies. Our results suggest that H. scutatum eDNA is distributed sporadically at low quantities in pools; we recommend that future surveillance efforts prioritize increased frequency and quantity of sample collection per site visit and include repeat surveys of candidate sites. Further work to characterize Ranavirus eDNA movement, temporal trends, relationship to infectious virion, and decay is needed to help advance this tool.

OBJECTIVE To understand large animal veterinarians’ knowledge of select zoonotic diseases that cause livestock abortions and identify barriers to using personal protective equipment (PPE). SAMPLE A convenience sample of 469 veterinarians currently working with livestock. PROCEDURES We sent an electronic survey invitation to large animal veterinarians through various veterinary organizations. Respondents answered questions addressing knowledge and prior experience with select abortion-associated zoonotic diseases, resources available for infection control, attitudes and barriers to PPE use, and demographics. RESULTS Median participant age was 49 years (range, 22 to 82 years), and 54% (235/438) were male. Half of veterinarians (185/348) were contacted 5 or fewer times per year to consult on livestock abortions. No veterinarians surveyed answered all questions on zoonotic disease transmission correctly. Personal protective equipment access varied, from 99% (289/290) having access to gloves to 20% (59/290) having access to respirators. Concerns for spreading disease to other animals (136/289 [47%]) and to other humans (108/287 [38%]) ranked as the most common reported motivators for PPE use. Reported barriers to PPE use among survey participants were the inconvenience of taking PPE into the field (101/286 [35%]) and the inconvenience of wearing PPE (97/286 [34%]). Access to PPE was not correlated with PPE use. CLINICAL RELEVANCE Surveyed veterinarians had limited knowledge of transmission of select abortion-associated zoonotic diseases. Incomplete understanding might lead to inappropriate PPE selection, preventable disease exposure, or missed opportunities for client education. Inconvenience was a primary reason PPE was not used.

Tylosin phosphate (TYL) is administered to more than 50% of U.S. beef cattle to reduce the incidence of liver abscesses but may increase the risk of macrolide-lincosamide-streptogramin-resistant bacteria disseminating from the feedlot. Limited evidence has been collected to understand how TYL affects the proportion of resistant bacteria in cattle or the feedlot environment. We created a mathematical model to investigate the effects of TYL administration on Enterococcus dynamics and examined preharvest strategies to mitigate the impact of TYL administration on resistance. The model simulated the physiological pharmacokinetics of orally administered TYL and estimated the pharmacodynamic effects of TYL on populations of resistant and susceptible Enterococcus within the cattle large intestine, feedlot pen, water trough, and feed bunk. The model parameters' population distributions were based on the available literature; 1000 Monte Carlo simulations were performed to estimate the likely distribution of outcomes. At the end of the simulated treatment period, the median estimated proportion of macrolide-resistant enterococci was only 1 percentage point higher within treated cattle compared with cattle not fed TYL, in part because the TYL concentrations in the large intestine were substantially lower than the enterococci minimum inhibitory concentrations. However, 25% of the simulated cattle had a >10 percentage point increase in the proportion of resistant enterococci associated with TYL administration, termed the TYL effect. The model predicts withdrawing TYL treatment and moving cattle to an antimicrobial-free terminal pen with a low prevalence of resistant environmental enterococci for as few as 6 days could reduce the TYL effect by up to 14 percentage points. Additional investigation of the importance of this subset of cattle to the overall risk of resistance transmission from feedlots will aid in the interpretation and implementation of resistance mitigation strategies.

Consumption of unpasteurized milk in the United States has presented a public health challenge for decades because of the increased risk of pathogen transmission causing illness outbreaks. We analyzed Foodborne Disease Outbreak Surveillance System data to characterize unpasteurized milk outbreaks. Using Poisson and negative binomial regression, we compared the number of outbreaks and outbreak-associated illnesses between jurisdictions grouped by legal status of unpasteurized milk sale based on a May 2019 survey of state laws. During 2013-2018, 75 outbreaks with 675 illnesses occurred that were linked to unpasteurized milk; of these, 325 illnesses (48%) were among people aged 0-19 years. Of 74 single-state outbreaks, 58 (78%) occurred in states where the sale of unpasteurized milk was expressly allowed. Compared with jurisdictions where retail sales were prohibited (n=24), those where sales were expressly allowed (n=27) were estimated to have 3.2 (95% CI:1.4-7.6) times greater number of outbreaks; of these, jurisdictions where sale was allowed in retail stores (n=14) had 3.6 (95% CI:1.3-9.6) times greater number of outbreaks compared with those where sale was allowed on-farm only (n=13).This study supports findings of previously published reports indicating that state laws resulting in increased availability of unpasteurized milk are associated with more outbreak-associated illnesses and outbreaks.