Cronobacter sakazakii is an opportunistic pathogen associated with bloodstream infections and meningitis in neonates and infants. C. sakazakii isolated from infants under 1 year of age has been reportable in Minnesota since 2003. Invasive Cronobacter infections in infants was recently made notifiable nationally in 2024. Therefore, this summary of over 20 years of reportable surveillance for C. sakazakii from Minnesota infants will inform other jurisdictions. During 2002-2024, 23 C. sakazakii cases in infants, including 8 invasive and 15 non-invasive cases, were identified and confirmed using MALDI-TOF or conventional biochemical methods. Invasive cases were younger (median, 18 days; range, 8 days to 10 months) than non-invasive cases (median, 98 days; range, 7 days to 8 months). Cronobacter isolates from infant (21), child (4), and adult (15) cases were submitted for whole genome sequencing (WGS) to obtain a contextual understanding of potential relatedness. In addition, C. sakazakii isolated from powdered infant formula (PIF) in 2003 was sequenced for comparison. Sequence type (ST) 4 was responsible for the majority of C. sakazakii cases overall (65%) and invasive infant cases (88%). Opened and unopened PIF was cultured from 10 investigations representing both invasive and non-invasive cases. Two (25%) opened PIF samples tested positive for C. sakazakii ST 4 while one (11%) unopened PIF sample tested positive for C. sakazakii ST 4. WGS demonstrated that no clinical cases were associated with a recognized outbreak. Several cases were likely due to contamination of PIF in the home during preparation, highlighting the importance of infant caregiver education to prevent infections.

Introduction Erysipelothrix rhusiopathiae is a gram-positive, rod-shaped bacterium that can cause infections in livestock, marine mammals and humans. Human infections are traditionally affiliated with occupational exposures to E. rhusiopathiae through farming, butchering, or cooking. In July 2024, the Minnesota Department of Health was notified of two E. rhusiopathiae infections in the Minneapolis-St. Paul metropolitan area. Concerned about a possible outbreak, an investigation was initiated to determine the possible source(s) of infection.Methods Epidemiologists conducted reiterative, semi-structured interviews with the families of each case-patient. Cultures were forwarded to the MDH Public Health Laboratory for next-generation sequencing to determine the relatedness of the two samples, and additional queries of electronic health records (EHRs) were utilised to detect any additional cases of E. rhusiopathiae occurring in the Minneapolis-St. Paul area.Results Both case-patients were adults from the Hmong community with underlying health conditions that presented to emergency care on two separate occasions. Interviews with the case-patients' families elucidated that they may have had direct or indirect exposures to raw or undercooked meat, possibly from a live animal market, but otherwise had no similar exposures. At MDH-PHL, the isolates were confirmed as E. rhusiopathiae and were noted to be 23,328 single nucleotide polymorphisms different. No additional case-patients were identified through a query of EHRs.Conclusions Given the lack of an epidemiological linkage and no apparent genetic relatedness of these two samples, epidemiologists considered these cases to likely not be part of an outbreak. While the true source of infection for these cases could not be determined, interviews helped elucidate possible exposure routes of infection, including contact with undercooked meat or environmental exposure to surfaces contaminated by raw meat. Given its rarity, E. rhusiopathiae cases should be studied when they occur to establish greater epidemiological and molecular evidence to support future outbreak investigations of the pathogen.

Evidence suggests that Shiga toxin-producing Escherichia coli (STEC) strains do not persist at the farm level. We hypothesized that ecosystem-level STEC persistence occurs and contributes significantly to disease burden. We tested this by identifying locally persistent lineages (LPLs) of STEC O157:H7 in Minnesota. We identified 15 distinct LPLs, which were associated with 35.3% of reported cases in Minnesota and persisted for 1.3-8.6 years. Locally persistent lineages were associated with multiple outbreaks with Minnesota sources and no multi-state outbreaks, and LPL cases were spatially clustered. Our findings show long-term persistence in defined geographic areas, suggesting the importance of ecosystem-level persistence.

Abstract Campylobacter jejuni is a leading cause of foodborne gastroenteritis globally and is classified by the CDC as a serious public health threat due to increasing resistance to fluoroquinolones and macrolides. This study used whole-genome sequencing to characterize the virulence and antimicrobial resistance profiles of 2,783 clinical C. jejuni isolates collected from Minnesota residents from 2018 through 2021. More than 90% of the isolates had genes related to stress defense ( rpoN and htrB ), cytolethal distending toxin ( cdtA, cdtB , and cdtC ), and cell adhesion and invasion ( ciaB, cadF , and flaC ). A diverse array of antimicrobial resistance genes was detected, with beta-lactam resistance genes having a particularly high prevalence. The gyrA point mutation associated with quinolone resistance was present in 29% of isolates. To evaluate the correlation between genotypic and phenotypic antimicrobial resistance profiles, the antimicrobial susceptibility testing results from a subset of isolates were compared with genotypic resistance profiles. Results showed a strong overall correlation, particularly for tetracycline and quinolones, though 24 discrepancies were detected. In the majority of discrepancies (n=21), genomic antimicrobial resistance markers were absent in isolates that were phenotypically resistant, suggesting possible unknown resistance mechanisms or limitations in current sequencing methods. The remaining three discrepancies occurred in isolates that had the tet (O) resistance gene but were susceptible to tetracycline phenotypically. These findings highlight the value of whole genome sequencing in improving antimicrobial resistance surveillance and understanding virulence factors in C. jejuni , supporting its integration into routine monitoring practices to better manage and understand antimicrobial resistance in foodborne pathogens.

BACKGROUND & AIMS: Postinfection irritable bowel syndrome (PI-IBS) is well-known epidemiologically; however, its physiological and molecular characteristics are not well studied. We aimed to determine the physiological phenotypes, colonic transcriptome, fecal microbiome, and metabolome in PI-IBS. METHODS: Fifty-one Rome III Campylobacter PI-IBS patients and 39 healthy volunteers (HV) were enrolled. Participants completed questionnaires, in vivo intestinal permeability, gastrointestinal transit, and rectal sensation. Fecal samples were collected for shotgun metagenomics, untargeted metabolomics, and sigmoid colonic biopsies for bulk RNAseq. Differential gene expression, differences in microbiota composition, and metabolite abundance were determined. Gene and metabolite clusters were identified via weighted gene correlation network analysis and correlations with clinical and physiological parameters determined. RESULTS: PI-IBS (59% female; 46 +/- 2 years) and HV (64% female; 42 +/- 2 years) demographics were comparable. Mean IBS-symptom severity score was 227; 94% were nonconstipation. Two- to 24-hour lactulose excretion was increased in PI-IBS, suggesting increased colonic permeability (4.4 +/- 0.5 mg vs 2.6 +/- 0.3 mg; P [ .01). Colonic transit and sensory thresholds were similar between the 2 groups. Overall, expression of 2036 mucosal genes and 223 fecal metabolites were different, with changes more prominent in females. Fecal N-acetylputrescine was increased in PI-IBS and associated with colonic permeability, worse diarrhea, and negatively correlated with abundance of Collinsella aerofaciens. Histamine and N-acetylhistamine positively associated with 2- to 24-hour lactulose excretion. Eight weighted gene coexpression modules significantly correlated with phenotypes (sex, stool frequency, colonic permeability, transit). CONCLUSIONS: Campylobacter PI-IBS patients demonstrate higher colonic permeability, which associated with changes in polyamine and histamine metabolites. Female patients demonstrated greater molecular changes.

The control of zoonotic foodborne pathogens, including Shiga toxin-producing Escherichia coli (STEC), has proven difficult, in part because we know remarkably little about how these pathogens are maintained in an ecosystem. In response to this gap, we have developed a method for identifying pathogen strains that persistently infect defined human populations, which we call locally persistent lineages (LPLs). Using STEC O157:H7 in Minnesota as a model, we show that LPLs are widespread across the O157 phylogenetic tree, contribute significantly to local disease burden, and can persist for several years. They are also spatially clustered in an area with large populations of cattle, considered O157 STEC's primary reservoir. Our results suggest that STEC O157:H7 LPLs are established in ecological niches that support persistence. Identifying LPLs, and ultimately their reservoirs, can advance understanding of their disease ecology and provide opportunities for disease control at both local and national levels.

Objective: Food safety progress depends on the ability of public health agencies to detect and investigate foodborne disease outbreaks. The Integrated Food Safety Centers of Excellence identify and implement best practices and serve as resources for public health professionals who investigate enteric disease outbreaks. To target the needs of this diverse workforce, the Integrated Food Safety Centers of Excellence developed and assessed a professional tier framework and competencies. Methods: We described the characteristics of public health professionals who investigate enteric disease outbreaks in the epidemiology role in a conceptual tiered framework. We mapped core competencies to each tier and disseminated a survey to practitioners at local (June 2019) and state (August 2018) US public health agencies to evaluate the importance and frequency of each competency. Results: We developed 15 competencies on surveillance, outbreak detection, interview skills, investigation team, specimen testing, data analysis, hypothesis generation, study design, communication, enteric disease biology, control measures, legal authority, quality improvement, environmental health, and reporting to surveillance. The 286 survey respondents selected interview skills, surveillance, control measures, and hypothesis generation as the competencies most important to their work and most frequently performed. Conclusion: The Integrated Food Safety Centers of Excellence created the first published workforce framework and competencies for public health professionals who detect and investigate enteric disease outbreaks in the epidemiology role, in collaboration with local, state, and federal public health agencies and national organizations. These tools have been integrated into existing programs and can be used to develop training curricula, assess workforce competency over time, and identify priorities for continuing education and training.

Understanding drivers of disease vectors’ population dynamics is a pressing challenge. For short-lived organisms like mosquitoes, landscape-scale models must account for their highly local and rapid life cycles. Aedes aegypti, a vector of multiple emerging diseases, has become abundant in desert population centers where water from precipitation could be a limiting factor. To explain this apparent paradox, we examined Ae. aegypti abundances at > 660 trapping locations per year for 3 years in the urbanized Maricopa County (metropolitan Phoenix), Arizona, USA. We created daily precipitation layers from weather station data using a kriging algorithm, and connected localized daily precipitation to numbers of mosquitoes trapped at each location on subsequent days. Precipitation events occurring in either of two critical developmental periods for mosquitoes were correlated to suppressed subsequent adult female presence and abundance. LASSO models supported these analyses for female presence but not abundance. Precipitation may explain 72% of Ae. aegypti presence and 90% of abundance, with anthropogenic water sources supporting mosquitoes during long, precipitation-free periods. The method of using kriging and weather station data may be generally applicable to the study of various ecological processes and patterns, and lead to insights into microclimates associated with a variety of organisms’ life cycles.

Foodborne illness complaint systems that collect consumer reports of illness following exposure at a food establishment or event are a primary tool for detecting outbreaks of foodborne illness. Approximately, 75% of outbreaks reported to the national Foodborne Disease Outbreak Surveillance System are detected through foodborne illness complaints. The Minnesota Department of Health added an online complaint form to their existing statewide foodborne illness complaint system in 2017. During 2018-2021, online complainants tended to be younger than those who used traditional telephone hotlines (mean age 39 vs 46 years; p value < 0.0001), reported illnesses sooner following onset of symptoms (mean interval 2.9 vs 4.2 days; p value = 0.003), and were more likely to still be ill at the time of the complaint (69% vs 44%; p value < 0.0001). However, online complainants were less likely to have called the suspected establishment to report their illness than those who used traditional telephone hotlines (18% vs 48%; p value < 0.0001). Of the 99 outbreaks identified by the complaint system, 67 (68%) were identified through telephone complaints alone, 20 (20%) through online complaints alone, 11 (11%) using a combination of both, and 1 (1%) through email alone. Norovirus was the most common outbreak etiology identified by both complaint system methods, accounting for 66% of outbreaks identified only via telephone complaints and 80% of outbreaks identified only via online complaints. Due to the COVID-19 pandemic in 2020, there was a 59% reduction in telephone complaint volume compared to 2019. In contrast, online complaints experienced a 25% reduction in volume. In 2021, the online method became the most popular complaint method. Although most outbreaks detected by complaints were reported by telephone complaints alone, adding an online form for complaint reporting increased the number of outbreaks detected.

Culture-independent diagnostic tests (CIDTs) are increasingly used for clinical diagnosis of gastrointestinal diseases such as salmonellosis, Shiga toxin-producing E. coli disease, and shigellosis because of their speed, convenience, and generally high-performance characteristics. These tests are also used to screen potentially infectious asymptomatic persons during outbreak investigations in sensitive settings such as childcare, food service, and healthcare. However, only limited performance data are available for CIDTs used on specimens from asymptomatic persons. The Association of Public Health Laboratories (APHL) and Council of State and Territorial Epidemiologists (CSTE) convened a workgroup to examine the available scientific data to inform interim decision-making related to exclusion and readmission criteria for potentially infectious persons in sensitive settings, the risks and benefits of different testing strategies, and to identify knowledge gaps for further research. This is the report on the Workgroup findings.

Background No human rabies post-exposure prophylaxis (PEP) failure has been documented in the United States using modern cell culture-based vaccines. In January 2021, an 84-year-old male died from rabies 6 months after being bitten by a rabid bat despite receiving timely rabies PEP. We investigated the cause of breakthrough infection.Methods We reviewed medical records, laboratory results, and autopsy findings and performed whole-genome sequencing (WGS) to compare patient and bat virus sequences. Storage, administration, and integrity of PEP biologics administered to the patient were assessed; samples from leftover rabies immunoglobulin were evaluated for potency. We conducted risk assessments for persons potentially exposed to the bat and for close patient contacts.Results Rabies virus antibodies present in serum and cerebrospinal fluid were nonneutralizing. Antemortem blood testing revealed that the patient had unrecognized monoclonal gammopathy of unknown significance. Autopsy findings showed rabies meningoencephalitis and metastatic prostatic adenocarcinoma. Rabies virus sequences from the patient and the offending bat were identical by WGS. No deviations were identified in potency, quality control, administration, or storage of administered PEP. Of 332 persons assessed for potential rabies exposure to the case patient, 3 (0.9%) warranted PEP.Conclusions This is the first reported failure of rabies PEP in the Western Hemisphere using a cell culture-based vaccine. Host-mediated primary vaccine failure attributed to previously unrecognized impaired immunity is the most likely explanation for this breakthrough infection. Clinicians should consider measuring rabies neutralizing antibody titers after completion of PEP if there is any suspicion for immunocompromise. A patient died of bat-borne rabies despite receipt of post-exposure prophylaxis. Rabies biologics failure was ruled out; undiagnosed immunosuppression was the most likely explanation for the rare outcome. Post-vaccination serology should be considered for high-risk exposures and suspicion of immunocompromise.

Background On October 15, 2021, the Minnesota Department of Health began investigating a school cluster of students experiencing tic-like behaviors thought to be related to recent COVID-19. The objective of this report is to describe the investigation, key findings, and public health recommendations. Methods Affected students and proxies were interviewed with a standardized questionnaire including validated depression and anxiety screens. Results Eight students had tic-like behaviors lasting >24 h after initial report with onset during September 26–October 30, 2021. All eight students were females aged 15–17 years. All students either had a history of depression or anxiety or scored as having more than minimal anxiety or depression on validated screens. Four students previously had confirmed COVID-19: the interval between prior COVID-19 and tic symptom onset varied from more than a year prior to tic symptom onset to at the time of tic symptom onset. Conclusion The onset of tic-like behaviors at one school in Minnesota appeared to be related more to underlying mental health conditions than recent COVID-19. These findings highlight the need to better understand functional tic-like behaviors and adolescent mental health.

IMPORTANCE Characterizing rates of SARS-CoV-2 infection among vaccinated and unvaccinated persons with the same exposure is critical to understanding the association of vaccination with the risk of infection with the Delta variant. Additionally, evidence of Delta variant transmission by children to vaccinated adults has important public health implications. OBJECTIVE To characterize transmission and infection of SARS-CoV-2 among vaccinated and unvaccinated attendees of an indoor wedding reception. DESIGN, SETTING, AND PARTICIPANTS This cohort study included attendees at an indoor wedding reception in Minnesota in July 2021. Data were collected from REDCap surveys and routine surveillance interviews. The full list of attendees and a partial list of emails were obtained. Fiftyseven attendees completed the emailed survey. Eighteen additional attendees were identified from the state health department COVID-19 surveillance database. EXPOSURES Attendance at an indoor event. MAIN OUTCOMES AND MEASURES Risk of SARS-CoV-2 infection among vaccinated and unvaccinated attendees, identification of an index case, whole genome sequencing (WGS) to identify the COVID-19 variant, understanding of transmission patterns, and assessment of secondary transmission. The primary case definition was an individual with a positive SARS-CoV-2 test who attended the wedding in the 14 days prior to their illness. RESULTS Data were gathered for 75 attendees (mean [SE] age, 37.5 [13.7] years; 57 [ 76%] female individuals), of whom 56 (75%) were fully vaccinated, 4 (5%) were partially vaccinated, and 15 (20%) were unvaccinated. Of 62 attendees who were tested, 29 (47%) tested positive, including 16 of 46 fully vaccinated attendees (35%), 2 of 4 partially vaccinated attendees (50%), and 11 of 12 unvaccinated attendees (92%). Being unvaccinated was associated with a higher risk of infection compared with being vaccinated (risk ratio, 2.64; 95% CI, 1.71-4.06; P =.001). One unvaccinated adult required hospitalization. An unvaccinated child who was symptomatic on the event date was identified as the index case. Eleven specimens were available forWGS. All sequenced specimens were closely related andwere identified as the Delta variant. WGS supported secondary transmission from a vaccinated individual with SARS-CoV-2. CONCLUSIONS AND RELEVANCE This cohort study identified a COVID-19 Delta variant outbreak at an indoor event despite a high proportion of vaccinated attendees. It found that vaccination was associated with a reduced risk of infection.

The Minnesota Department of Health investigated a coronavirus disease 2019 (COVID-19) outbreak at a fitness center in Olmsted County, Minnesota. Twenty-three severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections (5 employees and 18 members) were identified. An epidemiological investigation supported by whole genome sequencing demonstrated that transmission of SARS-CoV-2 occurred at the fitness center despite following recommended prevention strategies.

AbstractCongregate settings and high-density workplaces have endured a disproportionate impact from COVID-19. In order to provide further understanding of the transmission patterns of SARS-CoV-2 in these settings, whole genome sequencing (WGS) was performed on samples obtained from 8 selected outbreaks in Minnesota from March – June, 2020. WGS and phylogenetic analysis was conducted on 319 samples, constituting 14.4% of the 2,222 total SARS-CoV-2-positive individuals associated with these outbreaks. Among the sequenced specimens, three LTCFs and both correctional facilities had spread associated with a single genetic sequence. A fourth LTCF had outbreak cases associated with two distinct sequences. In contrast, cases associated with outbreaks in the two meat processing plants represented multiple SARS-CoV-2 sequences. These results suggest that a single introduction of SARS-CoV-2 into a facility can result in a widespread outbreak, and early identification and cohorting of cases, along with continued vigilance with infection prevention and control measures is imperative.

Since the reemergence of St. Louis Encephalitis (SLE) Virus (SLEV) in the Southwest United States, identified during the 2015 outbreak in Arizona, SLEV has been seasonally detected within Culex spp. populations throughout the Southwest United States. Previous work revealed the 2015 outbreak was caused by an importation of SLEV genotype III, which had only been detected previously in Argentina. However, little is known about when the importation occurred or the transmission and genetic dynamics since its arrival into the Southwest. In this study, we sought to determine whether the annual detection of SLEV in the Southwest is due to enzootic cycling or new importations. To address this question, we analyzed 174 SLEV genomes (142 sequenced as part of this study) using Bayesian phylogenetic analyses to estimate the date of arrival into the American Southwest and characterize the underlying population structure of SLEV. Phylogenetic clustering showed that SLEV variants circulating in Maricopa and Riverside counties form two distinct populations with little evidence of inter-county transmission since the onset of the outbreak. Alternatively, it appears that in 2019, Yuma and Clark counties experienced annual importations of SLEV that originated in Riverside and Maricopa counties. Finally, the earliest representatives of SLEV genotype III in the Southwest form a polytomy that includes both California and Arizona samples. We propose that the initial outbreak most likely resulted from the importation of a population of SLEV genotype III variants, perhaps in multiple birds, possibly multiple species, migrating north in 2013, rather than a single variant introduced by one bird.

Campylobacter enterocolitis can lead to post-infection irritable bowel syndrome (PI-IBS) but the factors promoting its emergence are poorly understood. While some C. jejuni strains are more significant for human disease, genomic and virulence characteristics that promote PI-IBS development are unknown. We combined pangenome-wide association studies and laboratory microbiology to compare C. jejuni from patients that develop PI-IBS with those that do not. Variation in bacterial stress response (Cj0145_phoX), adhesion protein (Cj0628_CapA), and core biosynthetic pathway genes (biotin: Cj0308_bioD; purine: Cj0514_purQ; isoprenoid: Cj0894c_ispH) associated with PI-IBS development. In vitro assays demonstrated enhanced adhesion, invasion, epithelial barrier disruption, and IL-8 secretion with PI-IBS strains. Twenty-two genomic markers, four of which in an uncharacterized gene Cj1631c, were used to develop a risk-score for PI-IBS development. Demonstrating that specific Campylobacter genotypes confer greater in vitro virulence and increased risk of PI-IBS has potential to improve understanding of the complex host-pathogen interactions underlying this condition.