Eubacterium callanderi bacteremia: A case report.

Eubacterium species are a group of obligated anaerobic gram-positive bacilli that are recognized as commensals of the gastrointestinal tract flora. Cases of bacteremia mediated by Eubacterium are rare. This report describes a case of bacteremia caused by Eubacterium callanderi in an 82-year-old female with a history of a cecal perforation secondary to an obstructing sigmoid stricture. The results showed the utility of using whole genome sequencing to identify the causative agent and underlined the significance to identify anaerobic organisms in diagnostic microbiology practice and to perform antimicrobial susceptibility testing to guide therapy and enhance patient outcomes.

Confirmed Case of Longstanding Respiratory Francisella tularensis holarctica Infection: Nebraska, 2022.

A male patient with distant history of extensive rabbit contact and pulmonary nodules for 6 years developed empyema. Francisella tularensis holarctica was isolated from thoracentesis fluid. Retrospective immunohistochemical examination of a pulmonary nodule, biopsied 3 years prior, was immunoreactive for F. tularensis. These findings suggest the potential for chronic tularemia.

Significant variation of filamentation phenotypes in clinical Candida albicans strains.

Introduction: Candida albicans is an opportunistic human pathogen that typically resides as part of the microbiome in the gastrointestinal and genitourinary tracts of a large portion of the human population. This fungus lacks a true sexual cycle and evolves in a largely clonal pattern. The ability to cause disease is consistent across the species as strains causing systemic infections appear across the known C. albicans intra-species clades. Methods: In this work, strains collected from patients with systemic C. albicans infections isolated at the Nebraska Medicine clinical laboratory were typed by MLST analysis. Since the ability to form filaments has been linked to pathogenesis in C. albicans, these clinical strains, as well as a previously genotyped set of clinical strains, were tested for their ability to filament across a variety of inducing conditions. Results: Genotyping of the clinical strains demonstrated that the strains isolated at one of the major medical centers in our region were as diverse as strains collected across the United States. We demonstrated that clinical strains exhibit a variety of filamentation patterns across differing inducing conditions. The only consistent pattern observed in the entire set of clinical strains tested was an almost universal inability to filament in standard solid inducing conditions used throughout the C. albicans field. A different solid filamentation assay that produces more robust filamentation profiles from clinical strains is proposed in this study, although not all strains expected to filament in vivo were filamentous in this assay. Discussion: Our data supports growing evidence that broad phenotypic diversity exists between the C. albicans type strain and clinical strains, suggesting that the type strain poorly represents filamentation patterns observed in most clinical isolates. These data further highlight the need to use diverse clinical strains in pathogenesis assays.

Fatal Primary Amebic Meningoencephalitis in Nebraska: Case Report and Environmental Investigation, August 2022.

Primary amebic meningoencephalitis (PAM) is a rare and lethal infection caused by Naegleria fowleri. We report an epidemiological and environmental investigation relating to a case of PAM in a previously healthy boy age 8 years. An interview of the patient's family was conducted to determine the likely exposure site and to assess risk factors. Data from the United States Geological Survey site at Waterloo, NE, on the Elkhorn River were used to estimate water temperature and streamflow at the time and site of exposure. Data from the National Weather Service were used to estimate precipitation and ambient air temperature at the time and site of exposure. Despite conventional treatment, the patient died 2 days after hospital admission. The patient participated in recreational water activities in the Elkhorn River in northeastern Nebraska 5 days before symptom onset. In the week before exposure, water and ambient air high temperatures reached annual highs, averaging 32.4°C and 35.8°C, respectively. The day before infection, 2.2 cm of precipitation was reported. Streamflow was low (407 ft3/s). Infections in several northern states, including Nebraska, suggest an expanding geographic range of N. fowleri transmission, which may lead to increased incidence of PAM in the United States. Similar environmental investigations at suspected exposure sites of future cases will allow data aggregation, enabling investigators to correlate environmental factors with infection risk accurately.

A Public Health Laboratory Information System in Support of Health Emergencies: The Nebraska Public Health Laboratory COVID-19 Experience.

OBJECTIVES: Public health laboratories (PHLs) are essential components of US Public Health Service operations. The health information technology that supports PHLs is central to effective and efficient laboratory operations and overall public health response to infectious disease management. This analysis presents key information on how the Nebraska Public Health Laboratory (NPHL) information technology system evolved to meet the demands of the COVID-19 pandemic. MATERIALS AND METHODS: COVID-19 presented numerous, unforeseen information technology system challenges. The most notable challenges requiring changes to NPHL software systems and capability were improving efficiency of the laboratory operation due to high-volume testing, responding daily to demands for timely data for analysis by partner systems, interfacing with multiple testing (equipment) platforms, and supporting community-based specimen collection programs. RESULTS: Improvements to the NPHL information technology system enabled NPHL to perform >121 000 SARS-CoV-2 polymerase chain reaction tests from March 2020 through January 2022 at a sustainable rate of 2000 SARS-CoV-2 tests per day, with no increase in laboratory staffing. Electronic reporting of 62 000 rapid antigen tests eliminated paper reporting and extended testing services throughout the state. Collection of COVID-19 symptom data before specimen collection enabled NPHL to make data-driven decisions to perform pool testing and conserve testing kits when supplies were low. PRACTICE IMPLICATIONS: NPHL information technology applications proved essential for managing health care provider workload, prioritizing the use of scarce testing supplies, and managing Nebraska's overall pandemic response. The NPHL experience provides useful examples of a highly capable information technology system and suggests areas for additional attention in the PHL environment, including a focus on end users, collaboration with various partners, and investment in information technology.

Investigation of a SARS-CoV-2 B.1.1.529 (Omicron) Variant Cluster - Nebraska, November-December 2021.

The B.1.1.529 (Omicron) variant of SARS-CoV-2 (the virus that causes COVID-19) was first detected in specimens collected on November 11, 2021, in Botswana and on November 14 in South Africa;* the first confirmed case of Omicron in the United States was identified in California on December 1, 2021 (1). On November 29, the Nebraska Department of Health and Human Services was notified of six probable cases† of COVID-19 in one household, including one case in a man aged 48 years (the index patient) who had recently returned from Nigeria. Given the patient's travel history, Omicron infection was suspected. Specimens from all six persons in the household tested positive for SARS-CoV-2 by reverse transcription-polymerase chain reaction (RT-PCR) testing on December 1, and the following day genomic sequencing by the Nebraska Public Health Laboratory identified an identical Omicron genotype from each specimen (Figure). Phylogenetic analysis was conducted to determine if this cluster represented an independent introduction of Omicron into the United States, and a detailed epidemiologic investigation was conducted. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.§.

Genotypic Characterization of Multidrug-Resistant Pseudomonas aeruginosa Using Whole-Genome Sequencing.

Multidrug-resistant Pseudomonas aeruginosa is a serious threat worldwide causing health care-acquired infections and is associated with significant morbidity and mortality. This report describes the draft genome sequences of five multidrug-resistant Pseudomonas aeruginosa strains isolated from human infections.

Identification of an mcr-9-Carrying Salmonella enterica Serotype Heidelberg Strain Isolated from Blood.

Salmonella enterica, represented by a large number of serotypes, can cause a broad variety of diseases that range from mild gastroenteritis to severe systemic infections. This report provides a draft genome sequence of an mcr-9-carrying Salmonella enterica serotype Heidelberg strain isolated from blood.

Characterization of Carbapenem-Resistant Acinetobacter baumannii Isolates from Clinical Specimens.

Carbapenem-resistant Acinetobacter baumannii is an urgent threat worldwide. This bacterium is associated with high morbidity and mortality, with limited available treatment options. Here, we report the draft genome sequences of five carbapenem-resistant Acinetobacter baumannii isolates from human samples.

Differences in Blood-derived Francisella tularensis Type B Strains from Clinical Cases of Tularemia.

Francisella tularensis can cause the zoonotic disease tularemia and is partitioned into subspecies due to differences in chromosomal organization and virulence. The subspecies holarctica (type B) is generally considered more clonal than the other subpopulations with moderate virulence compared to the hypervirulent A.I clade. We performed whole genome sequencing (WGS) on six type B strains isolated from the blood of patients with tularemia within a one-year period from the same United States region, to better understand the associated pathogenicity. The WGS data were compared to the prototype strain for this subspecies, specifically FSC200, which was isolated from a patient with tularemia in Europe. These findings revealed 520-528 single nucleotide polymorphisms (SNPs) between the six United States type B strains compared to FSC200, with slightly higher A+T content in the latter strain. In contrast, comparisons between the six type B isolates showed that five of the six type B isolates had only 4-22 SNPs, while one of the strains had 47-53 SNPs. Analysis of SNPs in the core genome for the six United States type B isolates and the FSC200 strain gave similar results, suggesting that some of these mutations may have been nonsynonymous, resulting in altered protein function and pathogenicity.

Assessment of Specimen Pooling to Conserve SARS CoV-2 Testing Resources.

Objectives To establish the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2. Methods The most efficient pool size was determined to be 5 specimens using a web-based application. From this analysis, 25 experimental pools were created using 50 microliter from one SARS-CoV-2 positive nasopharyngeal specimen mixed with 4 negative patient specimens (50 microliter each) for a total volume of 250 microliter l. Viral RNA was subsequently extracted from each pool and tested using the CDC SARS-CoV-2 RT-PCR assay. Positive pools were consequently split into individual specimens and tested by extraction and PCR. This method was also tested on an unselected group of 60 nasopharyngeal specimens grouped into 12-pools. Results All 25 pools were positive with Cycle threshold (Ct) values within 0 and 5.03 Ct of the original individual specimens. The analysis of 60 specimens determined that two pools were positive followed by identification of two individual specimens among the 60 tested. This testing was accomplished while using 22 extractions/PCR tests, a savings of 38 reactions. Conclusions When the incidence rate of SARS-CoV-2 infection is 10% or less, group testing will result in the saving of reagents and personnel time with an overall increase in testing capability of at least 69%.

Tests in short supply? Try group testing.

Christopher R. Bilder, Peter C. Iwen, Baha Abdalhamid, Joshua M. Tebbs and Christopher S. McMahan explain how, by pooling specimens, testing capacity for SARS-CoV-2 can be increased.

Assessment of Specimen Pooling to Conserve SARS CoV-2 Testing Resources.

OBJECTIVES: To establish the optimal parameters for group testing of pooled specimens for the detection of SARS-CoV-2. METHODS: The most efficient pool size was determined to be five specimens using a web-based application. From this analysis, 25 experimental pools were created using 50 µL from one SARS-CoV-2 positive nasopharyngeal specimen mixed with 4 negative patient specimens (50 µL each) for a total volume of 250 µL. Viral RNA was subsequently extracted from each pool and tested using the CDC SARS-CoV-2 RT-PCR assay. Positive pools were consequently split into individual specimens and tested by extraction and PCR. This method was also tested on an unselected group of 60 nasopharyngeal specimens grouped into 12 pools. RESULTS: All 25 pools were positive with cycle threshold (Ct) values within 0 and 5.03 Ct of the original individual specimens. The analysis of 60 specimens determined that 2 pools were positive followed by identification of 2 individual specimens among the 60 tested. This testing was accomplished while using 22 extractions/PCR tests, a savings of 38 reactions. CONCLUSIONS: When the incidence rate of SARS-CoV-2 infection is 10% or less, group testing will result in the saving of reagents and personnel time with an overall increase in testing capability of at least 69%.

Genotyping and Subtyping Cryptosporidium To Identify Risk Factors and Transmission Patterns - Nebraska, 2015-2017.

Cryptosporidium is an enteric pathogen that is transmitted through animal-to-person or person-to-person contact or through ingestion of contaminated water or food. In the United States, Cryptosporidium affects an estimated 750,000 persons each year; however, only approximately 11,000 cases are reported nationally (1,2). Persons infected with Cryptosporidium typically develop symptoms within 2 to 10 days after exposure. Common symptoms include watery diarrhea, abdominal cramps, nausea, vomiting, or fever, which can last 1 to 2 weeks. Cryptosporidiosis is a nationally notifiable disease in the United States. Nebraska presents a unique setting for the evaluation of this pathogen because, compared with other states, Nebraska has a greater reliance on agriculture and a higher proportion of the population residing and working in rural communities. Cryptosporidium species and subtypes are generally indistinguishable using conventional diagnostic methods. Using molecular characterization, Nebraska evaluated the genetic diversity of Cryptosporidium and found a dichotomy in the distribution of cases of cryptosporidiosis caused by Cryptosporidium parvum and Cryptosporidium hominis among rural and urban settings. Characterizing clusters of C. hominis cases revealed that several child care facilities were affected by the same subtype, suggesting community-wide transmission and indicating a need for effective exclusion policies. Several cases of cryptosporidiosis caused by non-C. parvum or non-C. hominis species and genotypes indicated unique animal exposures that were previously unidentified. This study enhanced epidemiologic data by validating known Cryptosporidium sources, confirming outbreaks, and, through repeat interviews, providing additional information to inform cryptosporidiosis prevention and control efforts.