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SUMMARY In August 2008, a large outbreak of Shiga toxin-producing Escherichia coli (STEC) O111:NM infections associated with a buffet-style restaurant in rural Oklahoma was identified. A case-control study of restaurant patrons and a retrospective cohort study of catered event attendees were conducted coupled with an environmental investigation to determine the outbreak's source and mode of transmission. Of 1823 persons interviewed, 341 (18·7%) met the outbreak case definition; 70 (20·5%) were hospitalized, 25 (7·3%) developed haemolytic uraemic syndrome, and one died. Multiple food items were significantly associated with illness by both bivariate and multivariate analyses, but none stood out as a predominant transmission vehicle. All water, food, and restaurant surface swabs, and stool cultures from nine ill employees were negative for the presence of Shiga toxin and E. coli O111:NM although epidemiological evidence suggested the outbreak resulted from cross-contamination of restaurant food from food preparation equipment or surfaces, or from an unidentified infected food handler. [ABSTRACT FROM AUTHOR]

Background: Candidemia is a common opportunistic infection causing substantial morbidity and mortality. Because of an increasing proportion of non-albicans Candida species and rising antifungal drug resistance, the Infectious Diseases Society of America (IDSA) changed treatment guidelines in 2016 to recommend echinocandins over fluconazole as first-line treatment for adults with candidemia. We describe candidemia treatment practices and adherence to the updated guidelines., Methods: During 2017-2018, the Emerging Infections Program conducted active population-based candidemia surveillance at 9 US sites using a standardized case definition. We assessed factors associated with initial antifungal treatment for the first candidemia case among adults using multivariable logistic regression models. To identify instances of potentially inappropriate treatment, we compared the first antifungal drug received with species and antifungal susceptibility testing (AFST) results from initial blood cultures., Results: Among 1835 patients who received antifungal treatment, 1258 (68.6%) received an echinocandin and 543 (29.6%) received fluconazole as initial treatment. Cirrhosis (adjusted odds ratio = 2.06; 95% confidence interval, 1.29-3.29) was the only underlying medical condition significantly associated with initial receipt of an echinocandin (versus fluconazole). More than one-half (n = 304, 56.0%) of patients initially treated with fluconazole grew a non-albicans species. Among 265 patients initially treated with fluconazole and with fluconazole AFST results, 28 (10.6%) had a fluconazole-resistant isolate., Conclusions: A substantial proportion of patients with candidemia were initially treated with fluconazole, resulting in potentially inappropriate treatment for those involving non-albicans or fluconazole-resistant species. Reasons for nonadherence to IDSA guidelines should be evaluated, and clinician education is needed., (Published by Oxford University Press for the Infectious Diseases Society of America 2021.)

Treatment of Shiga toxin-producing Escherichia coli O157 (O157) diarrhea with antimicrobials might alter the risk of hemolytic uremic syndrome (HUS). However, full characterization of which antimicrobials might affect risk is lacking, particularly among adults. To inform clinical management, we conducted a case-control study of residents of the FoodNet surveillance areas with O157 diarrhea during a 4-year period to assess antimicrobial class-specific associations with HUS among persons with O157 diarrhea. We collected data from medical records and patient interviews. We measured associations between treatment with agents in specific antimicrobial classes during the first week of diarrhea and development of HUS, adjusting for age and illness severity. We enrolled 1308 patients; 102 (7.8%) developed confirmed HUS. Antimicrobial treatment varied by age: <5 years (12.6%), 5-14 (11.5%), 15-39 (45.4%), ≥40 (53.4%). Persons treated with a β-lactam had higher odds of developing HUS (OR 2.80, CI 1.14-6.89). None of the few persons treated with a macrolide developed HUS, but the protective association was not statistically significant. Exposure to "any antimicrobial" was not associated with increased odds of HUS. Our findings confirm the risk of β-lactams among children with O157 diarrhea and extends it to adults. We observed a high frequency of inappropriate antimicrobial treatment among adults. Our data suggest that antimicrobial classes differ in the magnitude of risk for persons with O157 diarrhea.

Background: Candidemia is a common healthcare-associated bloodstream infection with high morbidity and mortality. There are no current estimates of candidemia burden in the United States (US)., Methods: In 2017, the Centers for Disease Control and Prevention conducted active population-based surveillance for candidemia through the Emerging Infections Program in 45 counties in 9 states encompassing approximately 17 million persons (5% of the national population). Laboratories serving the catchment area population reported all blood cultures with Candida, and a standard case definition was applied to identify cases that occurred in surveillance area residents. Burden of cases and mortality were estimated by extrapolating surveillance area cases to national numbers using 2017 national census data., Results: We identified 1226 candidemia cases across 9 surveillance sites in 2017. Based on this, we estimated that 22 660 (95% confidence interval [CI], 20 210-25 110) cases of candidemia occurred in the US in 2017. Overall estimated incidence was 7.0 cases per 100 000 persons, with highest rates in adults aged ≥ 65 years (20.1/100 000), males (7.9/100 000), and those of black race (12.3/100 000). An estimated 3380 (95% CI, 1318-5442) deaths occurred within 7 days of a positive Candida blood culture, and 5628 (95% CI, 2465-8791) deaths occurred during the hospitalization with candidemia., Conclusions: Our analysis highlights the substantial burden of candidemia in the US. Because candidemia is only one form of invasive candidiasis, the true burden of invasive infections due to Candida is higher. Ongoing surveillance can support future burden estimates and help assess the impact of prevention interventions., (Published by Oxford University Press for the Infectious Diseases Society of America 2020.)

Characteristics of vaccine-associated rash illness (VARI) and confirmed measles cases were compared during a measles outbreak. Although some clinical differences were noted, measles exposure and identification of the vaccine strain were helpful for public health decision-making. Rapid, vaccine strain-specific diagnostic assays will more efficiently distinguish VARI from measles., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Injection drug use (IDU) is a known, but infrequent risk factor on candidemia; however, the opioid epidemic and increases in IDU may be changing the epidemiology of candidemia., Methods: Active population-based surveillance for candidemia was conducted in selected US counties. Cases of candidemia were categorized as IDU cases if IDU was indicated in the medical records in the 12 months prior to the date of initial culture., Results: During 2017, 1191 candidemia cases were identified in patients aged >12 years (incidence: 6.9 per 100 000 population); 128 (10.7%) had IDU history, and this proportion was especially high (34.6%) in patients with candidemia aged 19-44. Patients with candidemia and IDU history were younger than those without (median age, 35 vs 63 years; P < .001). Candidemia cases involving recent IDU were less likely to have typical risk factors including malignancy (7.0% vs 29.4%; relative risk [RR], 0.2 [95% confidence interval {CI}, .1-.5]), abdominal surgery (3.9% vs 17.5%; RR, 0.2 [95% CI, .09-.5]), and total parenteral nutrition (3.9% vs 22.5%; RR, 0.2 [95% CI, .07-.4]). Candidemia cases with IDU occurred more commonly in smokers (68.8% vs 18.5%; RR, 3.7 [95% CI, 3.1-4.4]), those with hepatitis C (54.7% vs 6.4%; RR, 8.5 [95% CI, 6.5-11.3]), and in people who were homeless (13.3% vs 0.8%; RR, 15.7 [95% CI, 7.1-34.5])., Conclusions: Clinicians should consider injection drug use as a risk factor in patients with candidemia who lack typical candidemia risk factors, especially in those with who are 19-44 years of age and have community-associated candidemia., (© Published by Oxford University Press for the Infectious Diseases Society of America 2019.)

We conducted a cohort study to identify characteristics associated with testing for, and testing positive for, coccidioidomycosis among patients with community-acquired pneumonia in southern California, USA. Limited and delayed testing probably leads to underdiagnosis among non-Hispanic black, Filipino, or Hispanic patients and among high-risk groups, including persons in whom antimicrobial drug therapy has failed.

Background: Postdiarrheal hemolytic-uremic syndrome (D+HUS) following Shiga toxin-producing Escherichia coli (STEC) infection is a serious condition lacking specific treatment. Host immune dysregulation and genetic susceptibility to complement hyperactivation are implicated in non-STEC-related HUS. However, genetic susceptibility to D+HUS remains largely uncharacterized., Methods: Patients with culture-confirmed STEC diarrhea, identified through the Centers for Disease Control and Prevention FoodNet surveillance system (2007-2012), were serotyped and classified by laboratory and/or clinical criteria as having suspected, probable, or confirmed D+HUS or as controls and underwent genotyping at 200 loci linked to nondiarrheal HUS or similar pathologies. Genetic associations with D+HUS were explored by multivariable regression, with adjustment for known risk factors., Results: Of 641 enrollees with STEC O157:H7, 80 had suspected D+HUS (41 with probable and 32 with confirmed D+HUS). Twelve genes related to cytokine signaling, complement pathways, platelet function, pathogen recognition, iron transport, and endothelial function were associated with D+HUS in multivariable-adjusted analyses (P ≤ .05). Of 12 significant single-nucleotide polymorphisms (SNPs), 5 were associated with all levels of D+HUS (intergenic SNP rs10874639, TFRC rs3804141, EDN1 rs5370, GP1BA rs121908064, and B2M rs16966334), and 7 SNPs (6 non-complement related) were associated with confirmed D+HUS (all P < .05)., Conclusions: Polymorphisms in many non-complement-related genes may contribute to D+HUS susceptibility. These results require replication, but they suggest novel therapeutic targets in patients with D+HUS., (© The Author(s) 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Infections caused by pan-azole-resistant Aspergillus fumigatus strains have emerged in Europe and recently in the United States. Physicians specializing in infectious diseases reported observing pan-azole-resistant infections and low rates of susceptibility testing, suggesting the need for wider-scale testing.

Background: Botulism is a rare, life-threatening paralytic illness. Equine-derived heptavalent botulinum antitoxin (HBAT), the only currently available treatment for noninfant botulism in the United States, was licensed in 2013. No reports have systematically examined safety and clinical benefit of HBAT among botulism patients., Methods: From March 2010 through March 2013, we collected data prospectively and through medical record reviews of patients with confirmed or suspected botulism who were treated with HBAT under an expanded-access Investigational New Drug program., Results: Among 249 HBAT-treated patients, 1 (<1%) child experienced an HBAT-related serious adverse event (hemodynamic instability characterized by bradycardia, tachycardia, and asystole); 22 (9%) patients experienced 38 nonserious adverse events reported by physicians to be HBAT related. Twelve (5%) deaths occurred; all were determined to be likely unrelated to HBAT. Among 104 (42%) patients with confirmed botulism, those treated early (≤2 days) spent fewer days in the hospital (median, 15 vs 25 days; P < .01) and intensive care (10 vs 17 days; P = .04) than those treated later. Improvements in any botulism sign/symptom were detected a median of 2.4 days and in muscle strength a median of 4.8 days after HBAT., Conclusions: HBAT was safe and provided clinical benefit in treated patients. HBAT administration within 2 days of symptom onset was associated with shorter hospital and intensive care stays. These results highlight the importance of maintaining clinical suspicion for botulism among patients presenting with paralytic illness to facilitate early HBAT treatment before laboratory confirmation might be available. Clinical consultation and, if indicated, HBAT release, are available to clinicians 24/7 through their state health department in conjunction with CDC., (Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Background: Botulism is classically described as a bilateral, symmetric, descending flaccid paralysis in an afebrile and alert patient without sensory findings. We describe the reported spectrum of clinical findings among persons >12 months of age in the United States during 2002-2015., Methods: The Centers for Disease Control and Prevention collects clinical findings reported by physicians treating suspected cases of botulism nationwide. We analyzed symptoms and signs, and neuroimaging and cerebrospinal fluid (CSF) results. A case was defined as illness compatible with botulism with laboratory confirmation or epidemiologic link to a confirmed case, and presence or absence of at least 1 sign or symptom recorded. Physicians' differential diagnoses were evaluated., Results: Clinical information was evaluated for 332 botulism cases; data quality and completeness were variable. Most had no fever (99%), descending paralysis (93%), no mental status change (91%), at least 1 ocular weakness finding (84%), and neuroimaging without acute changes (82%). Some had paresthesias (17%), elevated CSF protein level (13%), and other features sometimes considered indicative of alternative diagnoses. Five of 71 (7%) cases with sufficient information were reported to have atypical findings (eg, at least 1 cranial nerve finding that was unilateral or ascending paralysis). Illnesses on the physician differential included Guillain-Barré syndrome (99 cases) and myasthenia gravis (76 cases) and, rarely, gastrointestinal-related illness (5 cases), multiple sclerosis (3 cases), sepsis (3 cases), and Lyme disease (2 cases)., Conclusions: Our analysis illustrates that classic symptoms and signs were common among patients with botulism but that features considered atypical were reported by some physicians. Diagnosis can be challenging, as illustrated by the broad range of illnesses on physician differentials., (Published by Oxford University Press for the Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

These guidelines are intended for use by healthcare professionals who care for children and adults with suspected or confirmed infectious diarrhea. They are not intended to replace physician judgement regarding specific patients or clinical or public health situations. This document does not provide detailed recommendations on infection prevention and control aspects related to infectious diarrhea., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Invasive aspergillosis (IA) and mucormycosis contribute to substantial mortality, especially among immunocompromised persons, including those with hematopoietic stem cell transplant (HSCT), hematologic malignancy (HM), and solid organ transplant (SOT)., Methods: Using International Classification of Diseases, Ninth Revision codes available in the National Inpatient Sample, a hospital discharge database, we estimated IA-related hospitalizations (IA-RH), mucormycosis-RH (M-RH), HSCT-RH, HM-RH, and SOT-RH during 2000-2013. United States census data were used to calculate overall M-RH and IA-RH rates and present trends; estimated annual numbers of HSCT-RH, HM-RH, and SOT-RH served as denominators to calculate M-RH and IA-RH rates occurring with these conditions. Weighted least-squares technique was used to test for linear trends and calculate average annual percentage change (APC)., Results: There were an estimated 169 110 IA-RH and 9966 M-RH during 2000-2013. Overall, IA-RH and M-RH rates per million persons rose from 32.8 to 46.0 (APC = +2.9; P < .001) and 1.7 to 3.4 (APC = +5.2%; P < .001), respectively, from 2000 to 2013. Among HSCT-RH, there was no significant change in M-RH rate, but a significant decline occurred in IA-RH rate (APC = -4.6%; P = .004). Among HM-RH, the rate of M-RH increased (APC = +7.0%; P < .001), but the IA-RH rate did not change significantly (APC = +1.2%; P = .073). Among SOT-RH, M-RH (APC = +6.3%; P = .038) and IA-RH rates (APC = +4.1%; P < .001) both increased., Conclusions: Overall IA-RH and M-RH rates increased during 2000-2013, with a doubling of M-RH. Mucormycosis-related hospitalization occurring in conjunction with certain comorbidities increased, whereas IA-RH rates among patients with the comorbidities, decreased, remained stable, or increased to a lesser extent than M-RH., (Published by Oxford University Press on behalf of Infectious Diseases Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

To determine frequency and risk for sporotrichosis-associated hospitalizations, we analyzed the US 2000-2013 National (Nationwide) Inpatient Sample. An estimated 1,471 hospitalizations occurred (average annual rate 0.35/1 million persons). Hospitalizations were associated with HIV/AIDS, immune-mediated inflammatory diseases, and chronic obstructive pulmonary disease. Although rare, severe sporotrichosis should be considered for at-risk patients.

Listeria monocytogenes (Lm) causes severe foodborne illness (listeriosis). Previous molecular subtyping methods, such as pulsed-field gel electrophoresis (PFGE), were critical in detecting outbreaks that led to food safety improvements and declining incidence, but PFGE provides limited genetic resolution. A multiagency collaboration began performing real-time, whole-genome sequencing (WGS) on all US Lm isolates from patients, food, and the environment in September 2013, posting sequencing data into a public repository. Compared with the year before the project began, WGS, combined with epidemiologic and product trace-back data, detected more listeriosis clusters and solved more outbreaks (2 outbreaks in pre-WGS year, 5 in WGS year 1, and 9 in year 2). Whole-genome multilocus sequence typing and single nucleotide polymorphism analyses provided equivalent phylogenetic relationships relevant to investigations; results were most useful when interpreted in context of epidemiological data. WGS has transformed listeriosis outbreak surveillance and is being implemented for other foodborne pathogens., (Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.)

Fungi are an integral part of the natural environment and, therefore, play many roles in relation to food: some fungi are used in food production, some are food sources themselves, and some are agents of food spoilage. Some fungi that contaminate food can also be harmful to human health. The harmful but noninfectious health consequences of mycotoxins have been well-characterized, but the extent to which fungi in food pose a risk for invasive infections is unknown. We conducted a literature review to identify cases of invasive fungal infections (IFIs) believed to have resulted from ingestion or inhalation of food, beverages, or dietary supplements (excluding Saccharomyces infections). We identified 11 publications describing cases or small outbreaks of IFIs related to foods or beverages and three describing IFIs related to dietary supplements. These food-associated IFIs were predominantly mold infections, and the few yeast infections were associated with dairy products. Suspected foodborne IFIs appear to be rare, but are increasingly described in the electronically searchable literature. They are associated with a variety of foods, are due to a variety of fungal pathogens, and primarily occur in persons with immunosuppressive conditions or other predisposing factors. Various guidelines for high-risk patients recommend avoidance of certain food products that may contain high levels of fungi, but further work is needed to evaluate the effectiveness of these restrictive diets in preventing fungal infections. The relationships between food spoilage, food insecurity, and IFI risk are another area that may warrant further exploration.

On September 17, 2015, the Pennsylvania Department of Health (PADOH) notified CDC of a cluster of three potentially health care-associated mucormycete infections that occurred among solid organ transplant recipients during a 12-month period at hospital A. On September 18, hospital B reported that it had identified an additional transplant recipient with mucormycosis. Hospitals A and B are part of the same health care system and are connected by a pedestrian bridge. PADOH requested CDC's assistance with an on-site investigation, which started on September 22, to identify possible sources of infection and prevent additional infections.

We report on a case of listeriosis in a patient who probably consumed a prepackaged romaine lettuce-containing product recalled for Listeria monocytogenes contamination. Although definitive epidemiological information demonstrating exposure to the specific recalled product was lacking, the patient reported consumption of a prepackaged romaine lettuce-containing product of either the recalled brand or a different brand. A multinational investigation found that patient and food isolates from the recalled product were indistinguishable by pulsed-field gel electrophoresis and were highly related by whole genome sequencing, differing by four alleles by whole genome multilocus sequence typing and by five high-quality single nucleotide polymorphisms, suggesting a common source. To our knowledge, this is the first time prepackaged lettuce has been identified as a likely source for listeriosis. This investigation highlights the power of whole genome sequencing, as well as the continued need for timely and thorough epidemiological exposure data to identify sources of foodborne infections.

Histoplasmosis has been described as the most common endemic mycosis in the United States. However, histoplasmosis is not nationally notifiable. Its presumed geographic distribution is largely derived from skin test surveys performed during the 1940s, and information about its local features comes primarily from outbreak investigations. We conducted a literature review to assess epidemiologic features of histoplasmosis outbreaks in the United States. During 1938-2013, a total of 105 outbreaks involving 2,850 cases were reported in 26 states and the territory of Puerto Rico. Common exposure settings were chicken coops and buildings or other structures undergoing renovation or demolition. Birds, bats, or their droppings were reported to be present in 77% of outbreak settings, and workplace exposures were reported in 41% of outbreaks. The continued occurrence of histoplasmosis outbreaks, particularly work-related ones involving known disturbance of bird or bat droppings, highlights the need to increase awareness of the disease.

Fungal diseases require greater attention today than ever before, given the expanding population of immunosuppressed patients who are at higher risk for these diseases. This article reports on distribution, incidence, and prevalence of various fungal diseases and points out gaps in knowledge where such data are not available. Fungal diseases that contribute substantially to global morbidity and mortality are highlighted. Long-term, sustainable surveillance programs for fungal diseases and better noninvasive and reliable diagnostic tools are needed to estimate the burden of these diseases more accurately., (Published by Elsevier Inc.)

We examined trends in histoplasmosis-associated hospitalizations in the United States using the 2001-2012 National (Nationwide) Inpatient Sample. An estimated 50 778 hospitalizations occurred, with significant increases in hospitalizations overall and in the proportion of hospitalizations associated with transplant, diabetes, and autoimmune conditions often treated with biologic therapies; therefore, histoplasmosis remains an important opportunistic infection.

During September 2012, CDC, in collaboration with state and local health departments and the Food and Drug Administration (FDA), investigated a multistate outbreak of fungal meningitis and other infections caused by injections of contaminated methylprednisolone acetate solution (MPA). After this unprecedented outbreak, scientists in the CDC Mycotic Diseases Branch, along with infectious diseases specialists who cared for patients from the outbreak, clinical experts, and public health officials from affected states, have continued to monitor the recovery of affected patients. A long-term follow-up study involving these patients was initiated and is being conducted by the Mycoses Study Group Education and Research Consortium (MSGERC). This update summarizes subsequent information about the current state of the outbreak.

Objective: To assess the clinical spectrum of postdiarrheal hemolytic uremic syndrome (D(+)HUS) hospitalizations and sought predictors of in-hospital death to help identify children at risk of poor outcomes., Study Design: We assessed clinical variables collected through population-based surveillance of D(+)HUS in children <18 years old hospitalized in 10 states during 1997-2012 as predictors of in-hospital death by using tree modeling., Results: We identified 770 cases. Of children with information available, 56.5% (430 of 761) required dialysis, 92.6% (698 of 754) required a transfusion, and 2.9% (22 of 770) died; few had a persistent dialysis requirement (52 [7.3%] of 716) at discharge. The tree model partitioned children into 5 groups on the basis of 3 predictors (highest leukocyte count and lowest hematocrit value during the 7 days before to 3 days after the diagnosis of hemolytic uremic syndrome, and presence of respiratory tract infection [RTI] within 3 weeks before diagnosis). Patients with greater leukocyte or hematocrit values or a recent RTI had a greater probability of in-hospital death. The largest group identified (n = 533) had none of these factors and had the lowest odds of death. Many children with RTI had recent antibiotic treatment for nondiarrheal indications., Conclusion: Most children with D(+)HUS have good hospitalization outcomes. Our findings support previous reports of increased leukocyte count and hematocrit as predictors of death. Recent RTI could be an additional predictor, or a marker of other factors such as antibiotic exposure, that may warrant further study., (Published by Elsevier Inc.)

On July 19, 2014, a packing company in California (company A) voluntarily recalled certain lots of stone fruits, including whole peaches, nectarines, plums, and pluots, because of concern about contamination with Listeria monocytogenes based on internal company testing. On July 31, the recall was expanded to cover all fruit packed at their facility during June 1-July 17. After the initial recall, clinicians, state and local health departments, CDC, and the Food and Drug Administration (FDA) received many inquiries about listeriosis from concerned consumers, many of whom had received automated telephone calls informing them that they had purchased recalled fruit. During July 19-31, the CDC Listeria website received >500,000 page views, more than seven times the views received during the previous 52 weeks. However, no molecular information from L. monocytogenes isolates was available to assess whether human illnesses might be linked to these products.

In July-August 2009, eight patients with bloody diarrhea complicated by hemolytic uremic syndrome (HUS) were admitted to hospitals in Tbilisi, Georgia. We started active surveillance in two regions for bloody diarrhea and post-diarrheal HUS. Of 25 case-patients who developed HUS, including the initial 8 cases, half were ⩾15 years old, 67% were female and seven (28%) died. No common exposures were identified. Among 20 HUS case-patients tested, Shiga toxin was detected in the stools of 2 patients (one with elevated serum IgG titers to several Escherichia coli serogroups, including O111 and O104). Among 56 persons with only bloody diarrhea, we isolated Shiga toxin-producing E. coli (STEC) O104:H4 from 2 and Shigella from 10; 2 had serologic evidence of E. coli O26 infection. These cases may indicate a previously unrecognized burden of HUS in Georgia. We recommend national reporting of HUS and improving STEC detection capacity., (Copyright © 2014 Ministry of Health, Saudi Arabia. All rights reserved.)

Non-O157 Shiga toxin-producing Escherichia coli (STEC) infections are increasingly detected, but sources are not well established. We summarize outbreaks to 2010 in the USA. Single-aetiology outbreaks were defined as ⩾2 epidemiologically linked culture-confirmed non-O157 STEC infections; multiple-aetiology outbreaks also had laboratory evidence of ⩾2 infections caused by another enteric pathogen. Twenty-six states reported 46 outbreaks with 1727 illnesses and 144 hospitalizations. Of 38 single-aetiology outbreaks, 66% were caused by STEC O111 (n = 14) or O26 (n = 11), and 84% were transmitted through food (n = 17) or person-to-person spread (n = 15); food vehicles included dairy products, produce, and meats; childcare centres were the most common setting for person-to-person spread. Of single-aetiology outbreaks, a greater percentage of persons infected by Shiga toxin 2-positive strains had haemolytic uraemic syndrome compared with persons infected by Shiga toxin 1-only positive strains (7% vs. 0·8%). Compared with single-aetiology outbreaks, multiple-aetiology outbreaks were more frequently transmitted through water or animal contact.

We describe multiple-aetiology infections involving non-O157 Shiga toxin-producing Escherichia coli (STEC) identified through laboratory-based surveillance in nine FoodNet sites from 2001 to 2010. A multiple-aetiology infection (MEI) was defined as isolation of non-O157 STEC and laboratory evidence of any of the other nine pathogens under surveillance or isolation of >1 non-O157 STEC serogroup from the same person within a 7-day period. We compared exposures of patients with MEI during 2001-2010 with those of patients with single-aetiology non-O157 STEC infections (SEI) during 2008-2009 and with those of the FoodNet population from a survey conducted during 2006-2007. In total, 1870 non-O157 STEC infections were reported; 68 (3.6%) were MEI; 60 included pathogens other than non-O157 STEC; and eight involved >1 serogroup of non-O157 STEC. Of the 68 MEI, 21 (31%) were part of six outbreaks. STEC O111 was isolated in 44% of all MEI. Of patients with MEI, 50% had contact with farm animals compared with 29% (P < 0.01) of persons with SEI; this difference was driven by infections involving STEC O111. More patients with non-outbreak-associated MEI reported drinking well water (62%) than respondents in a population survey (19%) (P < 0.01). Drinking well water and having contact with animals may be important exposures for MEI, especially those involving STEC O111., (© 2014 Blackwell Verlag GmbH.)

We investigated an outbreak of 396 Salmonella enterica serotype I 4,5,12:i:- infections to determine the source. After 7 weeks of extensive hypothesis-generation interviews, no refined hypothesis was formed. Nevertheless, a case-control study was initiated. Subsequently, an iterative hypothesis-generation approach used by a single interviewing team identified brand A not-ready-to-eat frozen pot pies as a likely vehicle. The case-control study, modified to assess this new hypothesis, along with product testing indicated that the turkey variety of pot pies was responsible. Review of product labels identified inconsistent language regarding preparation, and the cooking instructions included undefined microwave wattage categories. Surveys found that most patients did not follow the product's cooking instructions and did not know their oven's wattage. The manufacturer voluntarily recalled pot pies and improved the product's cooking instructions. This investigation highlights the value of careful hypothesis-generation and the risks posed by frozen not-ready-to-eat microwavable foods.

Vibrio parahaemolyticus (Vp) is found naturally in coastal saltwater. In the United States, Vp causes an estimated 35,000 domestically acquired foodborne infections annually, of which most are attributable to consumption of raw or undercooked shellfish. Illness typically consists of mild to moderate gastroenteritis, although severe infection can occur. Demographic, clinical, and exposure information (including traceback information on implicated seafood) for all laboratory-confirmed illnesses are reported by state health departments to CDC through the Cholera and Other Vibrio Surveillance system. Vp isolates are distinguished by serotyping (>90 serotypes have been described) and by pulsed-field gel electrophoresis (PFGE).

The emergence of epidemic cholera in post-earthquake Haiti portended a public health disaster of uncertain magnitude. In order to coordinate relief efforts in an environment with limited healthcare infrastructure and stretched resources, timely and realistic projections of the extent of the cholera outbreak were crucial. Projections were shared with Government and partner organizations beginning 5 days after the first reported case and were updated using progressively more advanced methods as more surveillance data became available. The first projection estimated that 105 000 cholera cases would occur in the first year. Subsequent projections using different methods estimated up to 652 000 cases and 163 000-247 000 hospitalizations during the first year. Current surveillance data show these projections to have provided reasonable approximations of the observed epidemic. Providing the real-time projections allowed Haitian ministries and external aid organizations to better plan and implement response measures during the evolving epidemic.

Background: Shiga toxin-producing Escherichia coli (STEC) are an important cause of diarrhea and the major cause of postdiarrheal hemolytic uremic syndrome. Non-O157 STEC infections are being recognized with greater frequency because of changing laboratory practices., Methods: Foodborne Diseases Active Surveillance Network (FoodNet) site staff conducted active, population-based surveillance for laboratory-confirmed STEC infections. We assessed frequency and incidence of STEC infections by serogroup and examined and compared demographic factors, clinical characteristics, and frequency of international travel among patients., Results: During 2000-2010, FoodNet sites reported 2006 cases of non-O157 STEC infection and 5688 cases of O157 STEC infections. The number of reported non-O157 STEC infections increased from an incidence of 0.12 per 100,000 population in 2000 to 0.95 per 100,000 in 2010; while the rate of O157 STEC infections decreased from 2.17 to 0.95 per 100,000. Among non-O157 STEC, six serogroups were most commonly reported: O26 (26%), O103 (22%), O111 (19%), O121 (6%), O45 (5%), and O145 (4%). Non-O157 STEC infections were more common among Hispanics, and infections were less severe than those caused by O157 STEC, but this varied by serogroup. Fewer non-O157 STEC infections were associated with outbreaks (7% versus 20% for O157), while more were associated with international travel (14% versus 3% for O157)., Conclusions: Improved understanding of the epidemiologic features of non-O157 STEC infections can inform food safety and other prevention efforts. To detect both O157 and non-O157 STEC infections, clinical laboratories should routinely and simultaneously test all stool specimens submitted for diagnosis of acute community-acquired diarrhea for O157 STEC and for Shiga toxin and ensure that isolates are sent to a public health laboratory for serotyping and subtyping.

Fresh salsa and guacamole often contain diced raw produce, are often made in large batches, and are often poorly refrigerated, which may make them prone to contamination that can cause foodborne illness. The safety of salsa and guacamole is increasingly important as these foods gain popularity. Since 1973, local, state, and territorial health departments have voluntarily reported foodborne disease outbreaks to the Centers for Disease Control and Prevention's Foodborne Disease Outbreak Surveillance System (FDOSS) using a standard reporting form. FDOSS used paper-based reporting for 1973-1997 and switched to electronic reporting for 1998-2008. We reviewed all reports of outbreaks during 1973-2008 in which salsa or guacamole was reported as a vehicle. We found 136 outbreaks in which salsa or guacamole was reported as a possible vehicle, which resulted in 5,658 illnesses. Of these 136 salsa- or guacamole-associated (SGA) outbreaks additional possible food vehicles were reported for 33 (24%) outbreaks. There were no SGA outbreaks reported before 1984. Among reported outbreaks, most were caused by norovirus (24%), nontyphoidal Salmonella (19%), and Shigella (7%). Eighty-four percent of outbreaks were caused by foods prepared in restaurants or delis; of these, 19% reported ill foodworkers, and 29% reported improper storage as possible contributing factors. Among all foodborne disease outbreaks with a reported food vehicle during 1984-1997, 26 (0.9%) of 2,966 outbreaks were SGA, and during 1998-2008, 110 (1.4%) of 7,738 outbreaks were SGA. The number of reported foodborne disease outbreaks attributable to salsa or guacamole increased in the United States from 1984 to 2008, especially in later years, and especially in restaurants. Fresh salsa and guacamole require careful preparation and storage. Focused prevention strategies should reduce the risk of illness and ensure that these foods are enjoyed safely.

Background: Yersinia enterocolitica causes an estimated 116,716 illnesses annually in the United States. Black children have historically had the highest rates of infection, with incidence peaking in the winter., Methods: The Foodborne Diseases Active Surveillance Network (FoodNet) conducts active surveillance for laboratory-confirmed Y. enterocolitica infections, defined as the isolation of Y. enterocolitica or unspeciated Yersinia from a human clinical specimen. We calculated the average annual crude incidence rate per 100,000 persons from 1996 through 2009 and described rates by age, race, and geographic site. To account for changes in the FoodNet catchment area, we used a negative binomial model to estimate statistical changes in incidence using the average annual incidence in 1996-1998 as the baseline., Results: From 1996 through 2009, 2085 Y. enterocolitica infections were reported to FoodNet. The average annual crude incidence was 0.5 per 100,000 persons and was highest in blacks (0.9 per 100,000 persons). Over time, the rate in blacks declined from 3.9 to 0.4 per 100,000 persons. Declines among other racial groups were not as pronounced. The largest decline occurred in black children <5 years old (from 41.5 per 100,000 persons in 1996 to 3.5 per 100,000 persons in 2009). From 2007 through 2009, the highest rate of infection was in Asian children (5.1 per 100,000 persons). Compared with 1996-1998, the incidence in 2009 was 66% (95% confidence interval, 51%-77%) lower among children <5 years old., Conclusions: Y. enterocolitica infections in FoodNet sites have significantly declined since 1996. These declines were greatest in young black children, the group that initially had the highest incidence, possibly as the result of educational efforts in Georgia.

Background: Shiga toxin-producing Escherichia coli (STEC) infections cause acute diarrheal illness and sometimes life-threatening hemolytic uremic syndrome (HUS). Escherichia coli O157 is the most common STEC, although the number of reported non-O157 STEC infections is growing with the increased availability and use of enzyme immunoassay testing, which detects the presence of Shiga toxin in stool specimens. Prompt and accurate diagnosis of STEC infection facilitates appropriate therapy and may improve patient outcomes., Methods: We mailed 2400 surveys to physicians in 8 Foodborne Diseases Active Surveillance Network (FoodNet) sites to assess their knowledge and practices regarding STEC testing, treatment, and reporting, and their interpretation of Shiga toxin test results., Results: Of 1102 completed surveys, 955 were included in this analysis. Most (83%) physicians reported often or always ordering a culture of bloody stool specimens; 49% believed that their laboratory routinely tested for STEC O157, and 30% believed that testing for non-O157 STEC was also included in a routine stool culture. Forty-two percent of physicians were aware that STEC, other than O157, can cause HUS, and 34% correctly interpreted a positive Shiga toxin test result. All STEC knowledge-related factors were strongly associated with correct interpretation of a positive Shiga toxin test result., Conclusions: Identification and management of STEC infection depends on laboratories testing for STEC and physicians ordering and correctly interpreting results of Shiga toxin tests. Although overall knowledge of STEC was low, physicians who had more knowledge were more likely to correctly interpret a Shiga toxin test result. Physician knowledge of STEC may be modifiable through educational interventions.

For decades, culture has been the mainstay of diagnostic testing for bacterial enteric pathogens. This paradigm is changing as clinical laboratories adopt culture-independent methods, such as antigen-based tests and nucleic acid-based assays. Public health surveillance for enteric infections addresses 4 interrelated but distinct objectives: case investigation for localized disease control; assessment of disease burden and trends to prioritize and assess impact of population-based control measures; outbreak detection; and microbiologic characterization to improve understanding of pathogens, their virulence mechanisms, and epidemiology. We summarize the challenges and opportunities that culture-independent tests present and suggest strategies, such as validation studies and development of culture-independent tests compatible with subtyping, that could be adopted to ensure that surveillance remains robust. Many of these approaches will require time and resources to implement, but they will be necessary to maintain a strong surveillance system. Public health practitioners must clearly explain the value of surveillance, especially how outbreak detection benefits the public, and collaborate with all stakeholders to develop solutions.

Background: Raw produce is an increasingly recognized vehicle for salmonellosis. We investigated a nationwide outbreak that occurred in the United States in 2008., Methods: We defined a case as diarrhea in a person with laboratory-confirmed infection with the outbreak strain of Salmonella enterica serotype Saintpaul. Epidemiologic, traceback, and environmental studies were conducted., Results: Among the 1500 case subjects, 21% were hospitalized, and 2 died. In three case-control studies of cases not linked to restaurant clusters, illness was significantly associated with eating raw tomatoes (matched odds ratio, 5.6; 95% confidence interval [CI], 1.6 to 30.3); eating at a Mexican-style restaurant (matched odds ratio, 4.6; 95% CI, 2.1 to ∞) and eating pico de gallo salsa (matched odds ratio, 4.0; 95% CI, 1.5 to 17.8), corn tortillas (matched odds ratio, 2.3; 95% CI, 1.2 to 5.0), or salsa (matched odds ratio, 2.1; 95% CI, 1.1 to 3.9); and having a raw jalapeño pepper in the household (matched odds ratio, 2.9; 95% CI, 1.2 to 7.6). In nine analyses of clusters associated with restaurants or events, jalapeño peppers were implicated in all three clusters with implicated ingredients, and jalapeño or serrano peppers were an ingredient in an implicated item in the other three clusters. Raw tomatoes were an ingredient in an implicated item in three clusters. The outbreak strain was identified in jalapeño peppers collected in Texas and in agricultural water and serrano peppers on a Mexican farm. Tomato tracebacks did not converge on a source., Conclusions: Although an epidemiologic association with raw tomatoes was identified early in this investigation, subsequent epidemiologic and microbiologic evidence implicated jalapeño and serrano peppers. This outbreak highlights the importance of preventing raw-produce contamination.

Background: In May 2008, PulseNet detected a multistate outbreak of Salmonella enterica serotype Saintpaul infections. Initial investigations identified an epidemiologic association between illness and consumption of raw tomatoes, yet cases continued. In mid-June, we investigated two clusters of outbreak strain infections in Texas among patrons of Restaurant A and two establishments of Restaurant Chain B to determine the outbreak's source., Methodology/principal Findings: We conducted independent case-control studies of Restaurant A and B patrons. Patients were matched to well controls by meal date. We conducted restaurant environmental investigations and traced the origin of implicated products. Forty-seven case-patients and 40 controls were enrolled in the Restaurant A study. Thirty case-patients and 31 controls were enrolled in the Restaurant Chain B study. In both studies, illness was independently associated with only one menu item, fresh salsa (Restaurant A: matched odds ratio [mOR], 37; 95% confidence interval [CI], 7.2-386; Restaurant B: mOR, 13; 95% CI 1.3-infinity). The only ingredient in common between the two salsas was raw jalapeño peppers. Cultures of jalapeño peppers collected from an importer that supplied Restaurant Chain B and serrano peppers and irrigation water from a Mexican farm that supplied that importer with jalapeño and serrano peppers grew the outbreak strain., Conclusions/significance: Jalapeño peppers, contaminated before arrival at the restaurants and served in uncooked fresh salsas, were the source of these infections. Our investigations, critical in understanding the broader multistate outbreak, exemplify an effective approach to investigating large foodborne outbreaks. Additional measures are needed to reduce produce contamination.

Case-control studies conducted during a multistate outbreak of Salmonella enterica serotype Saintpaul infections in 2008 revealed associations between illness and the consumption of jalapeño peppers, Serrano peppers, and tomatoes. Traceback investigations of implicated jalapeño and Serrano peppers led to farms in Tamaulipas and Nuevo León, Mexico. We conducted a novel analysis of a U.S. Food and Drug Administration database of tomatoes and jalapeño and Serrano peppers imported from Mexico during the first half of 2008 to describe the temporal and spatial flow of these items into the United States. Shipments of all three produce items followed a south-to-northwest corridor; 87% of peppers and 97% of tomatoes produced in Mexican states located west of the Sierra Madre Occidental were transported to ports in California and Arizona, and 90% of peppers and 100% of tomatoes produced in states east of the Sierra Madre Occidental were transported to ports east of Arizona. We found a significant correlation between state-specific infection rates and quantity of imported Mexican jalapeño and Serrano peppers to U.S. states by the first-level consignee but not for imported Mexican tomatoes. We localized production regions of interest by finding that quantities of both peppers and tomatoes imported from the states of Nuevo León and Tamaulipas were correlated with infection rates. In outbreaks possibly caused by agricultural commodities, analysis of import databases may foster a better understanding of growing seasons, harvest sites, shipment itineraries, and consignee destinations, thereby adding valuable insight into findings derived from epidemiologic studies.

Context: Healthy elderly persons commonly show 4 types of change in brain structure-cortical atrophy, central atrophy, deep white-matter hyperintensities, and periventricular hyperintensities-as forms of subclinical structural brain disease (SSBD)., Objectives: To characterize the volumes of SSBD present with aging and to determine the associations of SSBD, physiology, and cognitive function., Design: Cross-sectional study., Setting: University of California, Los Angeles, Neuropsychiatric Institute., Subjects: Forty-three community-dwelling healthy control subjects, aged 60 through 93 years., Main Outcome Measures: Volumetric magnetic resonance imaging, neuropsychological testing, and quantitative electroencephalographic coherence (functional connectivity) between brain regions., Results: Regression models demonstrated significant relationships between SSBD volumes, age, cognitive performance, and connectivity. Cortical and central atrophy and periventricular hyperintensities had significant associations with age while deep white-matter hyperintensities did not. Posterior atrophy showed stronger associations with age than did anterior atrophy. Only a subset of subjects at older ages showed large SSBD volumes; older subjects primarily showed increasing variance of SSBD. Although all subjects scored within the normal range on cognitive testing, SSBD volume was inversely related to performance, most notably on the Trail-Making Test part B and the Shipley-Hartford Abstract Reasoning test. Coherence had significant associations with SSBD. Path analysis supported mediation of the effects of deep white-matter hyperintensities and periventricular hyperintensities on cognition by altered connectivity. For several measures, cognitive performance was best explained by coherence, and only secondarily by SSBD., Conclusions: Modest volumes of SSBD were associated with decrements in cognitive performance within the normal range in healthy subjects. Lower coherence was associated with greater volumes of SSBD and increasing age. Path analysis models suggest that brain functional connectivity mediates some effects of SSBD on cognition.