Over the past decade, genomic characterization of Bordetella pertussis isolates recovered from US pertussis patients has unveiled noteworthy structural gene order variations. Whole-genome sequencing (WGS) shows that although B. pertussis exhibits little gene sequence variation, genomes from clinical isolates frequently differ in gene order through rearrangement between insertion sequence elements. To better understand rates of genome rearrangement and single nucleotide polymorphism (SNP) in B. pertussis, intra-patient genomic diversity was examined. Five states submitted, on average, five isolates per patient specimen following culture confirmation to the US Centers for Disease Control and Prevention for molecular characterization. Analysis of 149 patient specimen sets revealed only rare SNP variation, while isolate sets from 12 patients included genomic rearrangements that did not impact vaccine antigen production. To investigate the frequency and stability of such rearrangements during laboratory culture, replicate cultures of two pairs of isolates differing by duplication and inversion were subcultured for eight serial passages. WGS confirmed the initial presence of rare duplication mutations that became dominant in later passages, as well as the stable maintenance of a large, inverted genomic region during passage. These findings suggest that B. pertussis exhibits genomic diversity within a single clinical diagnostic specimen and acquires genomic variations during serial laboratory passages, indicative of bacterial genomic plasticity. Importantly, these rearrangements did not impact the frequency or distribution of SNPs. These results underscore the importance of minimizing the laboratory passaging of clinical isolates used for infectious disease surveillance. IMPORTANCE: The whooping cough-causing bacterium Bordetella pertussis can alter its genetic structure while conserving areas essential for vaccine efficacy. By examining B. pertussis from infected patients, we demonstrate the significance of reducing laboratory manipulation of bacteria to maintain reliable monitoring data from laboratory cultures. Public health officials can use these data to develop efficient disease control tactics and better understand B. pertussis's adaptability. This study highlights the importance of immunizations and the necessity of thorough genetic surveillance in the fight against this chronic and avoidable respiratory illness.

Persons who work in close contact with dairy cattle and poultry that are infected with highly pathogenic avian influenza (HPAI) A(H5N1) virus are at increased risk for infection. In July 2024, the Colorado Department of Public Health & Environment responded to two poultry facilities with HPAI A(H5N1) virus detections in poultry. Across the two facilities, 663 workers assisting with poultry depopulation (i.e., euthanasia) received screening for illness; 109 (16.4%) reported symptoms and consented to testing. Among those who received testing, nine (8.3%) received a positive influenza A(H5) virus test result, and 19 (17.4%) received a positive SARS-CoV-2 test result. All nine workers who received positive influenza A(H5) test results had conjunctivitis, experienced mild illness, and received oseltamivir. This poultry exposure-associated cluster of human cases of influenza A(H5) is the first reported in the United States. The identification of these cases highlights the ongoing risk to persons who work in close contact with infected animals. Early response to each facility using multidisciplinary, multilingual teams facilitated case-finding, worker screening, and treatment. As the prevalence of HPAI A(H5N1) virus clade 2.3.4.4b genotype B3.13 increases, U.S. public health agencies should prepare to rapidly investigate and respond to illness in agricultural workers, including workers with limited access to health care.

A COVID-19 outbreak occurred among Cameron Peak Fire responders in Colorado, USA, during August 2020-January 2021. The Cameron Peak Fire was the largest recorded wildfire in Colorado history, lasting August-December 2020. At least 6,123 responders were involved, including 1,260 firefighters in 63 crews who mobilized to the fire camps. A total of 79 COVID-19 cases were identified among responders, and 273 close contacts were quarantined. State and local public health investigated the outbreak and coordinated with wildfire management teams to prevent disease spread. We performed whole-genome sequencing and applied social network analysis to visualize clusters and transmission dynamics. Phylogenetic analysis identified 8 lineages among sequenced specimens, implying multiple introductions. Social network analysis identified spread between and within crews. Strategies such as implementing symptom screening and testing of arriving responders, educating responders about overlapping symptoms of smoke inhalation and COVID-19, improving physical distancing of crews, and encouraging vaccinations are recommended.

BACKGROUND: Nasopharyngeal specimens (NPS) are commonly used for SARS-CoV-2 testing but can be uncomfortable for patients. Self-collected saliva or anterior nasal specimens (ANS) for SARS-CoV-2 detection are less invasive but the sensitivity of these specimen types has not been thoroughly evaluated. METHODS: During September-November 2020, 730 adults undergoing SARS-CoV-2 testing at community testing events and homeless shelters in Denver provided self-collected saliva and ANS specimens before NPS collection and answered a short survey about symptoms and specimen preference. Specimens were tested for SARS-CoV-2 by rRT-PCR; viral culture was performed on a subset of specimens positive by rRT-PCR. Sensitivity of saliva and ANS for SARS-CoV-2 detection by rRT-PCR was measured against NPS. Subgroup analyses included test outcomes by symptom status and culture results. RESULTS: Sensitivity for SARS-CoV-2 detection by rRT-PCR appeared higher for saliva than for ANS (85% vs. 80%) and among symptomatic participants than among those without symptoms (94% vs. 29% for saliva; 87% vs. 50% for ANS). Among participants with culture-positive SARS-CoV-2 by any specimen type, sensitivity of saliva and ANS by rRT-PCR was 94% and 100%, respectively. Saliva and ANS were equally preferred by participants; most would undergo NPS again despite being least preferred. CONCLUSIONS: Saliva was slightly more sensitive than ANS for SARS-CoV-2 detection by rRT-PCR. Both saliva and ANS reliably detected SARS-CoV-2 among participants with symptoms. Self-collected saliva and ANS offer practical advantages, are preferred by patients, and might be most useful for testing people with COVID-19 symptoms.

OBJECTIVES: Public health laboratories (PHLs) provide essential services in the diagnosis and surveillance of diseases of public health concern, such as tuberculosis. Maintaining access to high-quality laboratory testing is critical to continued disease detection and decline of tuberculosis cases in the United States. We investigated the practical experience of sharing tuberculosis testing services between PHLs through the Shared Services Project. METHODS: The Shared Services Project was a 9-month-long project funded through the Association of Public Health Laboratories and the Centers for Disease Control and Prevention during 2012-2013 as a one-time funding opportunity to consortiums of PHLs that proposed collaborative approaches to sharing tuberculosis laboratory services. Submitting PHLs maintained testing while simultaneously sending specimens to reference laboratories to compare turnaround times. RESULTS: During the 9-month project period, 107 Mycobacterium tuberculosis complex submissions for growth-based drug susceptibility testing and molecular detection of drug resistance testing occurred among the 3 consortiums. The median transit time for all submissions was 1.0 day. Overall, median drug susceptibility testing turnaround time (date of receipt in submitting laboratory to result) for parallel testing performed in house by submitting laboratories was 31.0 days; it was 43.0 days for reference laboratories. The median turnaround time for molecular detection of drug resistance results was 1.0 day (mean = 2.8; range, 0-14) from specimen receipt at the reference laboratories. CONCLUSIONS: The shared services model holds promise for specialized tuberculosis testing. Sharing of services requires a balance among quality, timeliness, efficiency, communication, and fiscal costs.