Syndromic Gastrointestinal Panel Diagnostic Tests Have Changed our Understanding of the Epidemiology of Yersiniosis-Foodborne Diseases Active Surveillance Network, 2010-2021.

Background: In the US, yersinosis was understood to predominantly occur in winter and among Black or African American infants and Asian children. Increased use of culture-independent diagnostic tests (CIDTs) has led to marked increases in yersinosis diagnoses. Methods: We describe differences in the epidemiology of yersiniosis diagnosed by CIDT versus culture in 10 US sites, and identify determinants of health associated with diagnostic method. Results: Annual reported incidence increased from 0.3/100 000 in 2010 to 1.3/100 000 in 2021, particularly among adults ≥18 years, regardless of race and ethnicity, and during summer months. The proportion of CIDT-diagnosed infections increased from 3% in 2012 to 89% in 2021. An ill person's demographic characteristics and location of residence had a significant impact on their odds of being diagnosed by CIDT. Conclusions: Improved detection due to increased CIDT use has altered our understanding of yersinosis epidemiology, however differential access to CIDTs may still affect our understanding of yersinosis.

Extended-Spectrum Beta-Lactamase Shigella sonnei Cluster Among Men Who Have Sex with Men in Chicago, Illinois-July-October 2022.

Drug-resistant shigellosis is increasing, particularly among men who have sex with men (MSM). During July-October 2022, an extended-spectrum beta-lactamase producing Shigella sonnei cluster of 9 patients was identified in Chicago, of whom 8 were MSM and 6 were festival attendees. The cluster also included 4 domestic travelers to Chicago. Sexual health care for MSM should include shigellosis diagnosis and prevention.

Outbreak of multidrug-resistant Salmonella infections in people linked to pig ear pet treats, United States, 2015-2019: results of a multistate investigation.

Background: International distribution of contaminated foods can be a source of Salmonella infections in people and can contribute to the spread of antimicrobial-resistant bacteria across countries. We report an investigation led by the United States Centers for Disease Control and Prevention, the Food and Drug Administration (FDA), and state governmental officials into a multistate outbreak of salmonellosis linked to pig ear pet treats. Methods: Pig ear treats and companion dogs were tested for Salmonella by state officials and the FDA. Products were traced back to the country of origin when possible. Cases were defined as outbreak illnesses in people associated with one of seven Salmonella serotypes genetically related to samples from pig ear pet treats, with isolation dates from June 2015 to September 2019. Whole genome sequencing (WGS) of isolates was used to predict antimicrobial resistance. Findings: The outbreak included 154 human cases in 34 states. Of these, 107 of 122 (88%) patients reported dog contact, and 65 of 97 (67%) reported contact with pig ear pet treats. Salmonella was isolated from 137 pig ear treats, including some imported from Argentina, Brazil, and Colombia, and from four dogs. WGS predicted 77% (105/137) of human and 43% (58/135) of pig ear treat isolates were resistant to ≥3 antimicrobial classes. Interpretation: This was the first documented United States multistate outbreak of Salmonella infections linked to pig ear pet treats. This multidrug-resistant outbreak highlights the interconnectedness of human health and companion animal ownership and the need for zoonotic pathogen surveillance to prevent human illness resulting from internationally transported pet food products. Funding: Animal Feed Regulatory Program Standards award. Animal and product testing conducted by FDA Vet-LIRN was funded by Vet-LIRN infrastructure grants (PAR-22-063).

Multistate nontyphoidal Salmonella and Shiga toxin-producing Escherichia coli outbreaks linked to international travel-United States, 2017-2020.

Enteric bacterial infections are common among people who travel internationally. During 2017-2020, the Centers for Disease Control and Prevention investigated 41 multistate outbreaks of nontyphoidal Salmonella and Shiga toxin-producing Escherichia coli linked to international travel. Resistance to one or more antimicrobial agents was detected in at least 10% of isolates in 16 of 30 (53%) nontyphoidal Salmonella outbreaks and 8 of 11 (73%) Shiga toxin-producing E. coli outbreaks evaluated by the National Antimicrobial Resistance Monitoring System. At least 10% of the isolates in 14 nontyphoidal Salmonella outbreaks conferred resistance to one or more of the clinically significant antimicrobials used in human medicine. This report describes the epidemiology and antimicrobial resistance patterns of these travel-associated multistate outbreaks. Investigating illnesses among returned travellers and collaboration with international partners could result in the implementation of public health interventions to improve hygiene practices and food safety standards and to prevent illness and spread of multidrug-resistant organisms domestically and internationally.

Clinical Outcomes of Patients With Nontyphoidal Salmonella Infections by Isolate Resistance-Foodborne Diseases Active Surveillance Network, 10 US Sites, 2004-2018.

BACKGROUND: Nontyphoidal Salmonella causes an estimated 1.35 million US infections annually. Antimicrobial-resistant strains are a serious public health threat. We examined the association between resistance and the clinical outcomes of hospitalization, length-of-stay ≥3 days, and death. METHODS: We linked epidemiologic data from the Foodborne Diseases Active Surveillance Network with antimicrobial resistance data from the National Antimicrobial Resistance Monitoring System (NARMS) for nontyphoidal Salmonella infections from 2004 to 2018. We defined any resistance as resistance to ≥1 antimicrobial and clinical resistance as resistance to ampicillin, azithromycin, ceftriaxone, ciprofloxacin, or trimethoprim-sulfamethoxazole (for the subset of isolates tested for all 5 agents). We compared outcomes before and after adjusting for age, state, race/ethnicity, international travel, outbreak association, and isolate serotype and source. RESULTS: Twenty percent of isolates (1105/5549) had any resistance, and 16% (469/2969) had clinical resistance. Persons whose isolates had any resistance were more likely to be hospitalized (31% vs 28%, P = .01) or have length-of-stay ≥3 days (20% vs 16%, P = .01). Deaths were rare but more common among those with any than no resistance (1.0% vs 0.4%, P = .01). Outcomes for patients whose isolates had clinical resistance did not differ significantly from those with no resistance. After adjustment, any resistance (adjusted odds ratio 1.23, 95% confidence interval 1.04-1.46) remained significantly associated with hospitalization. CONCLUSIONS: We observed a significant association between nontyphoidal Salmonella infections caused by resistant pathogens and likelihood of hospitalization. Clinical resistance was not associated with poorer outcomes, suggesting that factors other than treatment failure (eg, strain virulence, strain source, host factors) may be important.

Healthcare providers' knowledge and clinical practice surrounding shigellosis - DocStyles Survey, 2020.

BACKGROUND: Shigellosis is an acute diarrheal disease transmitted through contaminated food, water, objects, poor hand hygiene, or sexual activity. Healthcare providers (HCP) may not be aware of the multiple routes of Shigella transmission, populations at increased risk, or importance of antibiotic susceptibility testing (AST). This study assessed HCP knowledge and clinical practices regarding shigellosis and antibiotic resistance. METHODS: Porter Novelli Public Services administered a web-based survey (Fall DocStyles 2020) to HCP in the United States. Pediatricians, primary care physicians, nurse practitioners, and physician assistants completed questions about knowledge and clinical practice of acute diarrhea and shigellosis. RESULTS: Of 2196 HCP contacted, 1503 responded (68% response rate). Most identified contaminated food (85%) and water (79%) as routes of Shigella transmission; fewer recognized person-to-person contact (40%) and sexual activity (18%). Men who have sex with men (MSM) were identified as being at risk for shigellosis by 35% of respondents. Most reported counseling patients to wash hands (86%) and avoid food preparation (77%) when ill with shigellosis; 29% reported recommending avoiding sex. Many HCP reported treating shigellosis empirically with ciprofloxacin (62%) and azithromycin (32%), and 29% reported using AST to guide treatment. CONCLUSIONS: We identified several gaps in shigellosis knowledge among HCP including MSM as a risk group, person-to-person transmission, and appropriate antibiotic use. Improving HCP education could prevent the spread of shigellosis, including drug-resistant infections, among vulnerable populations.

Strain of Multidrug-Resistant Salmonella Newport Remains Linked to Travel to Mexico and U.S. Beef Products - United States, 2021-2022.

In 2016, CDC identified a multidrug-resistant (MDR) strain of Salmonella enterica serotype Newport that is now monitored as a persisting strain (REPJJP01). Isolates have been obtained from U.S. residents in all 50 states and the District of Columbia, linked to travel to Mexico, consumption of beef products obtained in the United States, or cheese obtained in Mexico. In 2021, the number of isolates of this strain approximately doubled compared with the 2018-2020 baseline and remained high in 2022. During January 1, 2021- December 31, 2022, a total of 1,308 isolates were obtained from patients, cattle, and sheep; 86% were MDR, most with decreased susceptibility to azithromycin. Approximately one half of patients were Hispanic or Latino; nearly one half reported travel to Mexico during the month preceding illness, and one third were hospitalized. Two multistate outbreak investigations implicated beef products obtained in the United States. This highly resistant strain might spread through travelers, animals, imported foods, domestic foods, or other sources. Isolates from domestic and imported cattle slaughtered in the United States suggests a possible source of contamination. Safe food and drink consumption practices while traveling and interventions across the food production chain to ensure beef safety are necessary in preventing illness.

Epidemiology and Antimicrobial Resistance of Campylobacter Infections in the United States, 2005-2018.

Background: Campylobacter is the most common cause of bacterial diarrhea in the United States; resistance to macrolides and fluoroquinolones limits treatment options. We examined the epidemiology of US Campylobacter infections and changes in resistance over time. Methods: The Foodborne Diseases Active Surveillance Network receives information on laboratory-confirmed Campylobacter cases from 10 US sites, and the National Antimicrobial Resistance Monitoring System receives a subset of isolates from these cases for antimicrobial susceptibility testing. We estimated trends in incidence of Campylobacter infection, adjusting for sex, age, and surveillance changes attributable to culture-independent diagnostic tests. We compared percentages of isolates resistant to erythromycin or ciprofloxacin during 2005-2016 with 2017-2018 and used multivariable logistic regression to examine the association of international travel with resistance. Results: Adjusted Campylobacter incidence remained stable or decreased for all groups analyzed since 2012. Among 2449 linked records in 2017-2018, the median patient age was 40.2 years (interquartile range, 21.6-57.8 years), 54.8% of patients were male, 17.2% were hospitalized, and 0.2% died. The percentage of resistant infections increased from 24.5% in 2005-2016 to 29.7% in 2017-2018 for ciprofloxacin (P < .001) and from 2.6% to 3.3% for erythromycin (P = .04). Persons with recent international travel had higher odds than nontravelers of having isolates resistant to ciprofloxacin (adjusted odds ratio [aOR] varied from 1.7 to 10.6 by race/ethnicity) and erythromycin (aOR = 1.7; 95% confidence interval, 1.3-2.1). Conclusions: Campylobacter incidence has remained stable or decreased, whereas resistance to antimicrobials recommended for treatment has increased. Recent international travel increased the risk of resistance.

Estimating Waterborne Infectious Disease Burden by Exposure Route, United States, 2014.

More than 7.15 million cases of domestically acquired infectious waterborne illnesses occurred in the United States in 2014, causing 120,000 hospitalizations and 6,600 deaths. We estimated disease incidence for 17 pathogens according to recreational, drinking, and nonrecreational nondrinking (NRND) water exposure routes by using previously published estimates. In 2014, a total of 5.61 million (95% credible interval [CrI] 2.97-9.00 million) illnesses were linked to recreational water, 1.13 million (95% CrI 255,000-3.54 million) to drinking water, and 407,000 (95% CrI 72,800-1.29 million) to NRND water. Recreational water exposure was responsible for 36%, drinking water for 40%, and NRND water for 24% of hospitalizations from waterborne illnesses. Most direct costs were associated with pathogens found in biofilms. Estimating disease burden by water exposure route helps direct prevention activities. For each exposure route, water management programs are needed to control biofilm-associated pathogen growth; public health programs are needed to prevent biofilm-associated diseases.

Salmonella Outbreaks Linked to Beef, United States, 2012-2019.

The Centers for Disease Control and Prevention (CDC) has identified nontyphoidal Salmonella as one of the top five pathogens contributing to foodborne illnesses in the United States. Beef continues to be a common source of Salmonella outbreaks, despite the implementation of interventions at slaughter and processing facilities to reduce contamination of beef. We described Salmonella outbreaks linked to beef in the United States during 2012-2019, examined trends, and identified potential targets for intervention and prevention strategies. We queried CDC's Foodborne Disease Outbreak Surveillance System (FDOSS) for all foodborne nontyphoidal Salmonella outbreaks linked to beef as the single contaminated ingredient or implicated food, with the date of first illness onset from 2012 to 2019. Information on antimicrobial resistance (AR) for outbreak-related isolates was obtained from CDC's National Antimicrobial Resistance Monitoring System (NARMS). We calculated the number of outbreaks, outbreak-related illnesses, hospitalizations, and deaths overall, by beef processing category and Salmonella serotype. During 2012-2019, 27 Salmonella outbreaks were linked to beef consumption, resulting in 1103 illnesses, 254 hospitalizations, and two deaths. The most common category of beef implicated was nonintact raw, ground beef (12 outbreaks, 44%), followed by intact raw (six outbreaks, 22%). Ground beef was responsible for the most illnesses (800, 73%), both of the reported deaths, and was the source of the largest outbreak. AR data were available for 717 isolates from 25 (93%) outbreaks. Nine (36%) of these outbreaks had isolates resistant to one or more of the antibiotics tested by NARMS, of which eight (89%) contained multidrug-resistant isolates. Several outbreaks reported highlight challenges faced during investigations, areas where further research may be warranted, and opportunities to prevent future outbreaks along the farm-to-fork continuum.

First Known Report of mcr-Harboring Enterobacteriaceae in the Dominican Republic.

Colistin is a last-resort antibiotic used to treat infections caused by multidrug-resistant Gram-negative bacteria. People with a history of travel to the Dominican Republic have become sick with pathogenic bacteria carrying the mobile colistin resistance gene, mcr-1, during and after traveling. This investigation aimed to identify mcr genes in Enterobacteriaceae isolated from food animal sources in the Dominican Republic. Three hundred and eleven samples were tested, from which 1354 bacterial isolates were obtained. Real-time PCR tests showed that 70.7% (220 out of 311) of the samples and 3.2% (44 out of 1354) of the isolates tested positive for the mcr gene. All RT-PCR presumptive mcr-positive isolates (n = 44) and a subset (n = 133) of RT-PCR presumptive mcr-negative isolates were subjected to whole-genome sequencing. WGS analysis showed that 39 isolates carried the mcr gene, with 37 confirmed as positive through RT-PCR and two as negative. Further, all of the mcr-positive genomes were identified as Escherichia coli and all contained a IncX4 plasmid replicon. Resistant determinants for other antibiotics important for human health were found in almost all isolates carrying mcr genes.

Antibiotic prescribing for acute gastroenteritis during ambulatory care visits-United States, 2006-2015.

OBJECTIVE: To describe national antibiotic prescribing for acute gastroenteritis (AGE). SETTING: Ambulatory care. METHODS: We included visits with diagnoses for bacterial and viral gastrointestinal infections from the National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey (NAMCS/NHAMCS; 2006-2015) and the IBM Watson 2014 MarketScan Commercial Claims and Encounters Database. For NAMCS/NHAMCS, we calculated annual percentage estimates and 99% confidence intervals (CIs) of visits with antibiotics prescribed; sample sizes were too small to calculate estimates by pathogen. For MarketScan, we used Poisson regression to calculate the percentage of visits with antibiotics prescribed and 95% CIs, including by pathogen. RESULTS: We included 10,210 NAMCS/NHAMCS AGE visits; an estimated 13.3% (99% CI, 11.2%-15.4%) resulted in antibiotic prescriptions, most frequently fluoroquinolones (28.7%; 99% CI, 21.1%-36.3%), nitroimidazoles (20.2%; 99% CI, 14.0%-26.4%), and penicillins (18.9%; 99% CI, 11.6%-26.2%). In NAMCS/NHAMCS, antibiotic prescribing was least frequent in emergency departments (10.8%; 99% CI, 9.5%-12.1%). Among 1,868,465 MarketScan AGE visits, antibiotics were prescribed for 13.8% (95% CI, 13.7%-13.8%), most commonly for Yersinia (46.7%; 95% CI, 21.4%-71.9%), Campylobacter (44.8%; 95% CI, 41.5%-48.1%), Shigella (39.7%; 95% CI, 35.9%-43.6%), typhoid or paratyphoid fever (32.7%; (95% CI, 27.2%-38.3%), and nontyphoidal Salmonella (31.7%; 95% CI, 29.5%-33.9%). Antibiotics were prescribed for 12.3% (95% CI, 11.7%-13.0%) of visits for viral gastroenteritis. CONCLUSIONS: Overall, ∼13% of AGE visits resulted in antibiotic prescriptions. Antibiotics were unnecessarily prescribed for viral gastroenteritis and some bacterial infections for which antibiotics are not recommended. Antibiotic stewardship assessments and interventions for AGE are needed in ambulatory settings.

Genomic Diversity, Antimicrobial Resistance, and Virulence Gene Profiles of Salmonella Serovar Kentucky Isolated from Humans, Food, and Animal Ceca Content Sources in the United States.

Salmonella serovar Kentucky is frequently isolated from chickens and dairy cattle, but recovery from humans is comparatively low based on the U.S. National Antimicrobial Resistance Monitoring System (NARMS) reports. We aimed to better describe the genetic diversity, antimicrobial resistance, and virulence determinants of Salmonella Kentucky isolates from humans, food animal ceca, retail meat and poultry products, imported foods and food products, and other samples. We analyzed the genomes of 774 Salmonella Kentucky isolates and found that 63% (54/86) of human isolates were sequence type (ST)198, 33% (29/86) were ST152, and 3.5% (3/86) were ST314. Ninety-one percent (570/629) of cecal isolates and retail meat and poultry isolates were ST152 or ST152-like (one allele difference), and 9.2% (58/629) were ST198. Isolates from imported food were mostly ST198 (60%, 22/37) and ST314 (29.7%, 11/37). ST198 isolates clustered into two main lineages. Clade ST198.2 comprised almost entirely isolates from humans and imported foods, all containing triple mutations in the quinolone resistance-determining region (QRDR) that confer resistance to fluoroquinolones. Clade ST198.1 contained isolates from humans, ceca, retail meat and poultry products, and imported foods that largely lacked QRDR mutations. ST152 isolates from cattle had a lineage (Clade 2) distinct from ST152 isolates from chicken (Clade 4), and half of ST152 human isolates clustered within two other clades (Clades 1 and 3), largely distinct from Clades 2 and 4. Although clinical illness associated with Salmonella Kentucky is low, ST198 appears to account for most human infections in the Unites States but is uncommon among ceca of domestic food animals and retail meat and poultry products. These findings, combined with human exposure data, suggest that fluoroquinolone-resistant ST198 infections may be linked to the consumption of food products that are imported or consumed while traveling. We also found unique differences in the composition of virulence genes and antimicrobial resistance genes among the clades, which may provide clues to the host specificity and pathogenicity of Salmonella Kentucky lineages.

Outbreak of Multidrug-Resistant Salmonella Heidelberg Infections Linked to Dairy Calf Exposure, United States, 2015-2018.

In August 2016, the Wisconsin Department of Health Services notified the U.S. Centers for Disease Control and Prevention of multidrug-resistant (MDR) Salmonella enterica serovar Heidelberg infections in people who reported contact with dairy calves. Federal and state partners investigated this to identify the source and scope of the outbreak and to prevent further illnesses. Cases were defined as human Salmonella Heidelberg infection caused by a strain that had one of seven pulsed-field gel electrophoresis (PFGE) patterns or was related by whole genome sequencing (WGS), with illness onset from January 1, 2015, through July 2, 2018. Patient exposure and calf purchase information was collected and analyzed; calves were traced back from the point of purchase. Isolates obtained from animal and environmental samples collected on-farm were supplied by veterinary diagnostic laboratories and compared with patient isolates using PFGE and WGS. Antimicrobial susceptibility testing by standardized broth microdilution was performed. Sixty-eight patients from 17 states were identified. Forty (63%) of 64 patients noted cattle contact before illness. Thirteen (33%) of 40 patients with exposure to calves reported that calves were sick or had died. Seven individuals purchased calves from a single Wisconsin livestock market. One hundred forty cattle from 14 states were infected with the outbreak strain. WGS indicated that human, cattle, and environmental isolates from the livestock market were genetically closely related. Most isolates (88%) had resistance or reduced susceptibility to antibiotics of ≥5 antibiotic classes. This resistance profile included first-line antibiotic treatments for patients with severe salmonellosis, including ampicillin, ceftriaxone, and ciprofloxacin. In this outbreak, MDR Salmonella Heidelberg likely spread from sick calves to humans, emphasizing the importance of illness surveillance in animal populations to prevent future spillover of this zoonotic disease.

Characteristics of Reported Deaths Among Fully Vaccinated Persons With Coronavirus Disease 2019-United States, January-April 2021.

BACKGROUND: Vaccines against coronavirus disease 2019 (COVID-19) are highly efficacious, but severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections do occur after vaccination. We characterized COVID-19 cases among fully vaccinated persons with an outcome of death. METHODS: We analyzed COVID-19 cases voluntarily reported to the Centers for Disease Control and Prevention by US health departments from 1 January to 30 April 2021. We included cases among US residents with a positive SARS-CoV-2 test result ≥14 days after completion of an authorized primary vaccine series and who had a known outcome (alive or dead) as of 31 May 2021. When available, specimens were sequenced for viral lineage and death certificates were reviewed for cause(s) of death. RESULTS: Of 8084 fully vaccinated persons with reported COVID-19 during the surveillance period, 245 (3.0%) died. Compared with patients who remained alive, those who died were older (median age, 82 vs 57 years;), more likely to reside in a long-term care facility (51% vs 18%), and more likely to have ≥1 underlying health condition associated with risk for severe disease (64% vs 24%) (all P < .01). Among 245 deaths, 191 (78%) were classified as COVID-19 related. Of 106 deaths with available death certificates, COVID-19 was listed for 81 deaths (77%). There were no differences in the type of vaccine administered or the most common viral lineage (B.1.1.7). CONCLUSIONS: COVID-19 deaths are rare in fully vaccinated persons, occurring most commonly in those with risk factors for severe disease, including older age and underlying health conditions. All eligible persons should be fully vaccinated against COVID-19 and follow other prevention measures to mitigate exposure risk.

Extensively Drug-Resistant Typhoid Fever in the United States.

Cases of extensively drug-resistant (XDR) typhoid fever have been reported in the United States among patients who did not travel internationally. Clinicians should consider if and where the patient traveled when selecting empiric treatment for typhoid fever. XDR typhoid fever should be treated with a carbapenem, azithromycin, or both.

Mild Botulism From Illicitly Brewed Alcohol in a Large Prison Outbreak in Mississippi.

Botulism is typically described as a rapidly progressing, severe neuroparalytic disease. Foodborne botulism is transmitted through consuming food or drink that has been contaminated with botulinum toxin. During a botulism outbreak linked to illicitly brewed alcohol (also known as "hooch" or "pruno") in a prison, 11 (35%) of 31 inmates that consumed contaminated hooch had mild illnesses. This includes 2 inmates with laboratory confirmed botulism. The most frequently reported signs and symptoms among the 11 patients with mild illness included dry mouth (91%), hoarse voice (91%), difficulty swallowing (82%), fatigue (82%), and abdominal pain (82%). Foodborne botulism is likely underdiagnosed and underreported in patients with mild illness. Botulism should be considered on the differential diagnosis for patients with cranial nerve palsies.

Nasopharyngeal Carriage of Streptococcus pneumoniae Among Young Children in Haiti Before Pneumococcal Conjugate Vaccine Introduction.

BACKGROUND: Streptococcus pneumoniae, or pneumococcus, is a leading cause of morbidity and mortality in children worldwide. Pneumococcal conjugate vaccines (PCV) reduce carriage in the nasopharynx, preventing disease. We conducted a pneumococcal carriage study to estimate the prevalence of pneumococcal colonization, identify risk factors for colonization, and describe antimicrobial susceptibility patterns among pneumococci colonizing young children in Port-au-Prince, Haiti, before introduction of 13-valent PCV (PCV13). METHODS: We conducted a cross-sectional study of children aged 6-24 months at an immunization clinic in Port-au-Prince between September 2015 and January 2016. Consenting parents were interviewed about factors associated with pneumococcal carriage; nasopharyngeal swabs were collected from each child and cultured for pneumococcus after broth enrichment. Pneumococcal isolates were serotyped and underwent antimicrobial susceptibility testing. We compared frequency of demographic, clinical, and environmental factors among pneumococcus-colonized children (carriers) to those who were not colonized (noncarriers) using unadjusted bivariate analysis and multivariate logistic regression. RESULTS: Pneumococcus was isolated from 308 of the 685 (45.0%) children enrolled. Overall, 157 isolates (50.8%) were PCV13 vaccine-type serotypes; most common were 6A (13.3%), 19F (12.6%), 6B (9.7%), and 23F (6.1%). Vaccine-type isolates were significantly more likely to be nonsusceptible to ≥1 antimicrobial (63.1% vs 45.4%, P = .002). On bivariate analysis, carriers were significantly more likely than noncarriers to live in a household without electricity or running water, to share a bedroom with ≥3 people, to have a mother or father who did not complete secondary education, and to have respiratory symptoms in the 24 hours before enrollment (P < .05 for all comparisons). On multivariable analysis, completion of the pentavalent vaccination series (targeting diphtheria, pertussis, tetanus, hepatitis B, and Haemophilus influenzae type b) remained significantly more common among noncarriers. CONCLUSIONS: Nearly a quarter of healthy children surveyed in Haiti were colonized with vaccine-type pneumococcal serotypes. This baseline carriage study will enable estimation of vaccine impact following nationwide introduction of PCV13.

Ongoing Outbreak of Extensively Drug-Resistant Campylobacter jejuni Infections Associated With US Pet Store Puppies, 2016-2020.

Importance: Extensively drug-resistant Campylobacter jejuni infections cannot be treated with any commonly recommended antibiotics and pose an increasing public health threat. Objectives: To investigate cases of extensively drug-resistant C jejuni associated with pet store puppies and describe the epidemiologic and laboratory characteristics of these infections. Design, Setting, and Participants: In August 2017, health officials identified, via survey, patients with C jejuni infections who reported contact with puppies sold by pet stores. In conjunction with state and federal partners, the Centers for Disease Control and Prevention investigated cases of culture-confirmed C jejuni infections in US patients with an epidemiologic or molecular association with pet store puppies between January 1, 2016, and February 29, 2020. Available records from cases occurring before 2016 with genetically related isolates were also obtained. Main Outcomes and Measures: Patients were interviewed about demographic characteristics, health outcomes, and dog exposure during the 7 days before illness onset. Core genome multilocus sequence typing was used to assess isolate relatedness, and genomes were screened for resistance determinants to predict antibiotic resistance. Isolates resistant to fluoroquinolones, macrolides, and 3 or more additional antibiotic classes were considered to be extensively drug resistant. Cases before 2016 were identified by screening all sequenced isolates submitted for surveillance using core genome multilocus sequence typing. Results: A total of 168 patients (median [interquartile range] age, 37 [19.5-51.0] years; 105 of 163 female [64%]) with an epidemiologic or molecular association with pet store puppies were studied. A total of 137 cases occurred from January 1, 2016, to February 29, 2020, with 31 additional cases dating back to 2011. Overall, 117 of 121 patients (97%) reported contact with a dog in the week before symptom onset, of whom 69 of 78 (88%) with additional information reported contact with a pet store puppy; 168 isolates (88%) were extensively drug resistant. Traceback investigation did not implicate any particular breeder, transporter, distributer, store, or chain. Conclusions and Relevance: Strains of extensively drug-resistant C jejuni have been circulating since at least 2011 and are associated with illness among pet store customers, employees, and others who come into contact with pet store puppies. The results of this study suggest that practitioners should ask about puppy exposure when treating patients with Campylobacter infection, especially when they do not improve with routine antibiotics, and that the commercial dog industry should take action to help prevent the spread of extensively drug-resistant C jejuni from pet store puppies to people.

Comparison of Molecular Subtyping and Antimicrobial Resistance Detection Methods Used in a Large Multistate Outbreak of Extensively Drug-Resistant Campylobacter jejuni Infections Linked to Pet Store Puppies.

Campylobacter jejuni is a leading cause of enteric bacterial illness in the United States. Traditional molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE) and 7-gene multilocus sequence typing (MLST), provided limited resolution to adequately identify C. jejuni outbreaks and separate out sporadic isolates during outbreak investigations. Whole-genome sequencing (WGS) has emerged as a powerful tool for C. jejuni outbreak detection. In this investigation, 45 human and 11 puppy isolates obtained during a 2016-2018 outbreak linked to pet store puppies were sequenced. Core genome multilocus sequence typing (cgMLST) and high-quality single nucleotide polymorphism (hqSNP) analysis of the sequence data separated the isolates into the same two clades containing minor within-clade differences; however, cgMLST analysis does not require selection of an appropriate reference genome, making the method preferable to hqSNP analysis for Campylobacter surveillance and cluster detection. The isolates were classified as sequence type 2109 (ST2109)-a rarely seen MLST sequence type. PFGE was performed on 38 human and 10 puppy isolates; PFGE patterns did not reliably predict clustering by cgMLST analysis. Genetic detection of antimicrobial resistance determinants predicted that all outbreak-associated isolates would be resistant to six drug classes. Traditional antimicrobial susceptibility testing (AST) confirmed a high correlation between genotypic and phenotypic antimicrobial resistance determinations. WGS analysis linked C. jejuni isolates in humans and pet store puppies even when canine exposure information was unknown, aiding the epidemiological investigation during the outbreak. WGS data were also used to quickly identify the highly drug-resistant profile of these outbreak-associated C. jejuni isolates.