Genetics and Genomics Commons^™

Intellectual Disability Related To De Novo Germline Loss Of The Distal End Of The P-Arm Of Chromosome 17: A Case Report, Eden Pope, Matthew Huertas, Amar Paul, Braden Cunningham, Matthew Jennings, Ryan Perry, Stephanie Chavez, John A. Kriak, Kyle B. Bills, David W. Sant

Annual Research Symposium

Hypothesis/Purpose: In this report we present a case of a 20-year-old female with congenital intellectual disability, stunted growth, and hypothyroidism. Competitive genetic hybridization (CHG) revealed a loss of 17p13.3, and the deletion was not present in either parent. This deletion has not previously been characterized, but mutations on the p-arm of chromosome 17 are responsible for Miller-Dieker Syndrome and Isolated Lissencephaly Sequence, both of which share symptoms in common with the patient.

Methods: Peripheral mononuclear cells (PBMCs) were used for karyotyping and competitive genetic hybridization (CHG). Bioinformatic analysis was carried out using the Genome Data Viewer (ncbi.nlm.nih.gov/genome/gdv).

Results: Karyotype was …

Determination Of Feasibility And Plausibility Of Using Various Biological Samples For Remote Genetic Testing, Cole Farnsworth, Molly Henley, Walker Kay, Varos Victer Manukyan, Jonathon Reynolds, John A. Kriak, Kyle B. Bills, David W. Sant

Annual Research Symposium

No abstract provided.

Effects Of B4galnt1 Expression On Metastatic Phenotype And Response To Treatment In Osteosarcoma Cell Lines, Fatemeh Zareihajiabadi

Annual Research Symposium

No abstract provided.

Effects Of Post-Translational Histone Modifications On Transcription Rate, Aaron Bohn

Annual Research Symposium

No abstract provided.

Molecular Diagnosis Of Non X-Linked Ectodermal Dysplasias Using Next Generation Sequencing, Eman Abdelalim Rabie

Theses and Dissertations

Ectodermal Dysplasias (EDs) are rare heterogenous monogenic developmental disorders sharing the impairment of at least two surface ectoderm-derived organs. Symptoms characteristically manifest developmental abnormalities of the teeth, and three skin derivatives: hair follicles, nails, and sweat glands. The disease-causing gene was identified for only fewer than half of 160 characterized ED phenotypes. Expectedly, ED-causing genes regulate or function in ectodermal-developmental processes. The most common phenotype is hypohidrotic ED featuring teeth agenesis, and diminished or complete absence of hair and sweat production. Disease-causing variants of EDA, EDAR, EDARADD and WNT10A genes were identified in 60-90% of ED patients in …

Directed Carbapenemase Testing Is No Longer Just For Enterobacterales: Cost, Labor, And Workflow Assessment Of Expanding Carbapenemase Testing To Carbapenem-Resistant P. Aeruginosa, Fred C. Tenover, Christian M. Gill, Poonam Rajkotia, Amity L. Roberts, David P. Nicolau

Biology Faculty Publications

Molecular carbapenem-resistance testing, such as for the presence of carbapenemases genes, is commonly implemented for the detection of carbapenemase-producing Enterobacterales. Carbapenemase-producing P. aeruginosa is also associated with significant morbidity and mortality, although; prevalence may be underappreciated in the United States due to a lack of carbapenemase testing. The present study sought to compare hands-on time, cost and workflow implementation of carbapenemase gene testing in Enterobacterales and P. aeruginosa isolates versus sending out isolates to a public health laboratory (PHL) for testing to assess if in-house can provide actionable results. The time to carbapenemase gene results were compared. Differences in cost …

Genetic Determinants Involved In Acquisition Of Iron In The Opportunistic Pathogen Mycobacterium Abscessus, Manal F. Farhat

Dissertations, Theses, and Capstone Projects

The opportunistic pathogen Mycobacterium abscessus subsp. abscessus (Mab) has become an emerging public health threat due to the increasing number of Mab-associated chronic pulmonary disease cases. Infection cure rates are only 50% due to the complex resistance of Mab to most antimicrobial drugs and chemotherapy.

Deeper knowledge of Mab biology is needed to illuminate potential candidates for development of improved therapeutics against Mab infections. The ESX-3 type VII protein secretion system of Mab plays an important role in host inflammatory and pathological responses during infection.

In this study, we demonstrate a functional link between the ESX-3 secretion …

Biallelic Variants In Ogdh Encoding Oxoglutarate Dehydrogenase Lead To A Neurodevelopmental Disorder Characterized By Global Developmental Delay, Movement Disorder, And Metabolic Abnormalities, Ella F Whittle, Madison Chilian, Ehsan Ghayoor Karimiani, Helga Progri, Daniela Buhas, Melis Kose, Rebecca D Ganetzky, Mehran Beiraghi Toosi, Paria Najarzadeh Torbati, Reza Shervin Badv, Ivan Shelihan, Hui Yang, Houda Zghal Elloumi, Sukyeong Lee, Yalda Jamshidi, Alan M Pittman, Henry Houlden, Erika Ignatius, Shamima Rahman, Reza Maroofian, Wan Hee Yoon, Christopher J Carroll

Faculty, Staff and Students Publications

PURPOSE: This study aimed to establish the genetic cause of a novel autosomal recessive neurodevelopmental disorder characterized by global developmental delay, movement disorder, and metabolic abnormalities.

METHODS: We performed a detailed clinical characterization of 4 unrelated individuals from consanguineous families with a neurodevelopmental disorder. We used exome sequencing or targeted-exome sequencing, cosegregation, in silico protein modeling, and functional analyses of variants in HEK293 cells and Drosophila melanogaster, as well as in proband-derived fibroblast cells.

RESULTS: In the 4 individuals, we identified 3 novel homozygous variants in oxoglutarate dehydrogenase (OGDH) (NM_002541.3), which encodes a subunit of the tricarboxylic acid cycle enzyme …

Investigating The Absence Of A Dietary Response At The Neuromuscular Junction In Larval Drosophila Melanogaster, Suzanna Louise Marbach

Honors Program Theses and Research Projects

Research in Drosophila melanogaster (D. melanogaster) has been growing in order to identify the fundamental processes of human disorders of the central nervous system such as Alzheimer’s disease, diabetes, and other neurological disorders at a molecular level. Altered insulin signaling itself has been linked to widespread nervous system dysfunction including cognitive dysfunction, neuropathies, and susceptibility to neurodegenerative disease. However, knowledge of the cellular mechanisms underlying the effects of insulin on nervous system function is still incomplete. The focus behind investigating the insulin signaling pathway is derived from our observations in the adult D. melanogaster neuromuscular junction (NMJ) to changes in …

Molecular Regulation Of The Salicylic Acid Hormone Pathway In Plants Under Changing Environmental Conditions, Christina A. M. Rossi, Eric J. R. Marchetta, Jong Hum Kim, Christian Castroverde

Biology Faculty Publications

Salicylic acid (SA) is a central plant hormone mediating immunity, growth, and development. Recently, studies have highlighted the sensitivity of the SA pathway to changing climatic factors and the plant microbiome. Here we summarize organizing principles and themes in the regulation of SA biosynthesis, signaling, and metabolism by changing abiotic/biotic environments, focusing on molecular nodes governing SA pathway vulnerability or resilience. We especially highlight advances in the thermosensitive mechanisms underpinning SA-mediated immunity, including differential regulation of key transcription factors (e.g., CAMTAs, CBP60g, SARD1, bHLH059), selective protein–protein interactions of the SA receptor NPR1, and dynamic phase separation of the recently identified …

Nuclear Phylogeny And Insights Into Whole-Genome Duplications And Reproductive Development Of Solanaceae Plants, Jie Wang, Weibin Xu, Junwen Zhai, Yi Hu, Jing Guo, Caifei Zhang, Yiyong Zhao, Lin Zhang, Christopher T. Martine, Hong Ma, Chien-Hsun Huang

Faculty Journal Articles

Solanaceae, the nightshade family, have ∼2700 species, including the important crops potato and tomato, ornamentals, and medicinal plants. Several sequenced Solanaceae genomes show evidence for whole-genome duplication (WGD), providing an excellent opportunity to investigate WGD and its impacts. Here, we generated 93 transcriptomes/genomes and combined them with 87 public datasets, for a total of 180 Solanaceae species representing all four subfamilies and 14 of 15 tribes. Nearly 1700 nuclear genes from these transcriptomic/genomic datasets were used to reconstruct a highly resolved Solanaceae phylogenetic tree with six major clades. The Solanaceae tree supports four previously recognized subfamilies (Goetzeioideae, Cestroideae, Nicotianoideae, …

Selective Gsk3b Overexpression In Medial Prefrontal Cortex Camkiia Cells Produces Sex-Specific Changes In Ethanol Self-Administration, Anxiety-Like Behavior, And Working Memory, Sam Gottlieb, Zachary Tatom, Michael F. Miles

Graduate Research Posters

Background: Glycogen synthase kinase 3 beta (Gsk3b) is central in a gene network regulated by ethanol in mouse medial prefrontal cortex (mPFC). GSK3B abundance/activity modulations regulate ethanol consumption, suggesting GSK3B could be a target in treating alcohol use disorder. However, the critical cell type in this ethanol response is not yet known, nor have sex differences in GSK3B modulations been fully investigated. Here we report results of GSK3B overexpression selectively in CamKIIa⁺ mPFC cells on multiple behaviors.

Methods: Mice underwent stereotaxic injections to overexpress GSK3B in mPFC CamKIIa⁺ cells or control virus (n=4-6/sex/virus). We assayed working …

Morphological And Genetic Analysis Of The Root System In Two American Grapevines (Vitis Species), Parinaz Mohtasebi

Graduate Theses/Dissertations

The North American grapes species Vitis rupestris Scheele and Vitis riparia Michx have been the pillars of rootstock breeding for many decades. Though a large body of viticultural knowledge has been accumulated on their impact on grafted scions, the genetic basis of their root system architecture (RSA) has received limited scientific attention. In this study, I generated and analyzed adventitious root systems from dormant cuttings of 22 V. riparia and 19 V. rupestris accessions, as well as 162 interspecific F1 hybrid progeny from a cross between V. rupestris (♀) and V. riparia (♂). I photographed the roots and then extracted …

Novel Strategies In Head And Neck Tumor Therapy; Contribution Of Senescence In Therapy Response, And Resistance Development After Cisplatin Treatment, Fereshteh Ahmadinejad

Theses and Dissertations

Therapeutic outcomes achieved in head and neck squamous cell carcinoma (HNSCC) patients by concurrent cisplatin-based chemoradiotherapy initially reflect both tumor regression and tumor stasis. However, local, and distant metastasis and disease relapse as well as cisplatin-induced resistance are common in HNSCC patients. In the current work, we demonstrate that cisplatin treatment induces senescence in both p53 wild- type HN30 and p53 mutant HN12 head and neck cancer models. We also show that tumor cells can escape from senescence both in vitro and in vivo. We further established a cisplatin-resistant cell line from HN30 parental cell line that underwent brief senescence …

Hmgb2 Regulates The Differentiation And Stemness Of Exhausted Cd8+ T Cells During Chronic Viral Infection And Cancer, Emily N. Neubert, Julia M. Derogatis, Sloan A. Lewis, Karla M. Viramontes, Pedro Ortega, Monique L. Henriquez, Rémi Buisson, Ilhem Messaoudi, Roberto Tinoco

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chronic infections and cancers evade the host immune system through mechanisms that induce T cell exhaustion. The heterogeneity within the exhausted CD8⁺ T cell pool has revealed the importance of stem-like progenitor (Tpex) and terminal (Tex) exhausted T cells, although the mechanisms underlying their development are not fully known. Here we report High Mobility Group Box 2 (HMGB2) protein expression is upregulated and sustained in exhausted CD8⁺ T cells, and HMGB2 expression is critical for their differentiation. Through epigenetic and transcriptional programming, we identify HMGB2 as a cell-intrinsic regulator of the differentiation and maintenance of Tpex cells during …

Revolutionary Advances In The Treatment Of Genetic Disease, Emma Kaitlyn Carrigan

Honors Theses and Capstones

No abstract provided.

Campylobacter Vaccination Reduces Diarrheal Disease And Infant Growth Stunting Among Rhesus Macaques, Sara M. Hendrickson, Archana Thomas, Hans-Peter Raué, Kamm Prongay, Andrew J. Haertel, Nicholas S. Rhoades, Jacob F. Slifka, Lina Gao, Benjamin K. Quintel, Ian J. Amanna, Ilhem Messaoudi, Mark K. Slifka

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Campylobacter-associated enteric disease is estimated to be responsible for more than 160 million cases of gastroenteritis each year and is linked to growth stunting of infants living under conditions of poor sanitation and hygiene. Here, we examine naturally occurring Campylobacter-associated diarrhea among rhesus macaques as a model to determine if vaccination could reduce severe diarrheal disease and infant growth stunting. Compared to unvaccinated controls, there are no Campylobacter diarrhea-associated deaths observed among vaccinated infant macaques and all-cause diarrhea-associated infant mortality is decreased by 76% (P = 0.03). By 9 months of age, there is a 1.3 cm increase in dorsal …

Chronic Alcohol Consumption Dysregulates Innate Immune Response To Sars-Cov-2 In The Lung, Sloan A. Lewis, Isaac R. Cinco, Brianna M. Doratt, Madison B. Blanton, Cherise Hoagland, Natali Newman, Michael Davies, Kathleen A. Grant, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Background Alcohol consumption is widespread with over half of the individuals over 18 years of age in the U.S. reporting alcohol use in the last 30 days. Moreover, 9 million Americans engaged in binge or chronic heavy drinking (CHD) in 2019. CHD negatively impacts pathogen clearance and tissue repair, including in the respiratory tract, thereby increasing susceptibility to infection. Although, it has been hypothesized that chronic alcohol consumption negatively impacts COVID-19 outcomes; the interplay between chronic alcohol use and SARS-CoV-2 infection outcomes has yet to be elucidated.

Methods In this study we employed luminex, scRNA sequencing, and flow cytometry to …

Monoclonal Antibody Therapy Of Breastfeeding Patient Infected With Sars-Cov-2: A Case Report, Nicole E. Marshall, Madison B. Blanton, Brianna M. Doratt, Delphine C. Malherbe, Monica Rincon, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Introduction: Although safety data demonstrated the efficacy and effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination for all individuals over 6 months of age, including pregnant and breastfeeding individuals, optimal treatment courses for symptomatic pregnant and lactating individuals infected with SARS-CoV-2 remain to be defined. Case Description: A coronavirus disease 2019 (COVID-19)-vaccinated breastfeeding woman received anti-SARS-CoV-2 monoclonal antibody treatment casirivimab–imdevimab 5 days after diagnosis of a symptomatic breakthrough SARS-CoV-2 infection. Results and Conclusions: The patient did not present with obvious defects in innate or adaptive cellular subsets, but compared with controls had minimal maternal antibody response to recommended …

Mild/Asymptomatic Covid-19 In Unvaccinated Pregnant Mothers Impairs Neonatal Immune Responses, Brianna M. Doratt, Suhas Sureshchandra, Heather E. True, Monica Rincon, Nicole E. Marshall, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Maternal SARS-CoV-2 infection triggers placental inflammation and alters cord blood immune cell composition. However, most studies focus on outcomes of severe maternal infection. Therefore, we analyzed cord blood and chorionic villi from newborns of unvaccinated mothers who experienced mild/asymptomatic SARS-CoV-2 infection during pregnancy. We investigated immune cell rewiring using flow cytometry, single-cell RNA sequencing, and functional readouts using ex vivo stimulation with TLR agonists and pathogens. Maternal infection was associated with increased frequency of memory T and B cells and nonclassical monocytes in cord blood. Ex vivo T and B cell responses to stimulation were attenuated, suggesting a tolerogenic state. …

Integrated Single Cell Analysis Shows Chronic Alcohol Drinking Disrupts Monocyte Differentiation In The Bone Marrow, Sloan A. Lewis, Brianna M. Doratt, Qi Qiao, Madison B. Blanton, Kathleen A. Grant, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Chronic heavy alcohol drinking (CHD) rewires monocytes and macrophages toward heightened inflammatory states with compromised antimicrobial defenses that persist after 1-month abstinence. To determine whether these changes are mediated through alterations in the bone marrow niche, we profiled monocytes and hematopoietic stem cell progenitors (HSCPs) from CHD rhesus macaques using a combination of functional assays and single cell genomics. CHD resulted in transcriptional profiles consistent with increased activation and inflammation within bone marrow resident monocytes and macrophages. Furthermore, CHD resulted in transcriptional signatures associated with increased oxidative and cellular stress in HSCP. Differentiation of HSCP in vitro revealed skewing toward …

Multimodal Profiling Of Term Human Decidua Demonstrates Immune Adaptations With Pregravid Obesity, Suhas Sureshchandra, Brianna M. Doratt, Heather E. True, Norma Mendoza, Monica Rincon, Nicole E. Marshall, Ilhem Messaoudi

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Leukocyte diversity of the first-trimester maternal-fetal interface has been extensively described; however, the immunological landscape of the term decidua remains poorly understood. We therefore profiled human leukocytes from term decidua collected via scheduled cesarean delivery. Relative to the first trimester, our analyses show a shift from NK cells and macrophages to T cells and enhanced immune activation. Although circulating and decidual T cells are phenotypically distinct, they demonstrate significant clonotype sharing. We also report significant diversity within decidual macrophages, the frequency of which positively correlates with pregravid maternal body mass index. Interestingly, the ability of decidual macrophages to respond to …

Foraging Behavior In The Eastern Subterranean Termite, Reticulitermes Flavipes (Kollar) (Isoptera: Rhinotermitidae), Anugerah Fajar

Theses and Dissertations--Entomology

Foraging is essential for survival, but it can be unpredictably dangerous due to organismal interactions like competition and predation to various environmental factors. Animals have come up with strategies to safeguard foraging. Social insects, with their elaborate division of labor, have developed sophisticated systems of foraging task allocation that allow them to capitalize resources beyond their competitors. In this thesis, I delve into the subjects of foraging behavior, allocation strategies, and the genetic basis of foraging in the eastern subterranean termite, Reticulitermes flavipes, the most widely distributed termite species in North America and one of the most economically important …

Taxonomic Classification Of Viral And Bacterial Dna Following 2021 Avian Mass Mortality Event, Tessa Baillargeon

Honors Theses and Capstones

From May through July 2021, an unusual mortality event occurred along the eastern coast and Midwest of the United States. Thousands of birds, mostly from the order Passeriformes, were part of the die-off including blue jays (Cyanocitta cristata), common grackles (Quiscalus quiscula), European starlings (Sturnus vulgaris), American robins (Turdus migratorius). Clinical signs included crusted eyes, swollen conjunctiva, otitis, seizures, and ataxia.

The New Hampshire Veterinary Diagnostic Laboratory (NHVDL) received over 100 affected birds from various collaborators throughout the United States including Washington DC, NJ, CT, MD, and OH. Given the timing and geologic …

Therapeutic Neutralizing Monoclonal Antibody Administration Protects Against Lethal Yellow Fever Virus Infection, Michael J. Ricciardi, Lauren N. Rust, Nuria Pedreño-Lopez, Sofiya Yusova, Sreya Biswas, Gabriela M. Webb, Lucas Gonzalez-Nieto, Thomas B. Voigt, Johan J. Louw, Fernanda D. Laurino, John R. Dibello, Hans-Peter Raué, Aaron M. Barber-Axthelm, Kimberly Chun, Samantha Uttke, Lidiane M. S. Raphael, Aaron Yrizarry-Medina, Brandon C. Rosen, Rebecca Agnor, Lina Gao, Caralyn Labriola, Michael Axthelm, Jeremy Smedley, Justin G. Julander, Myrna C. Bonaldo, Laura M. Walker, Ilhem Messaoudi, Mark K. Slifka, Dennis R. Burton, Esper G. Kallas, Jonah B. Sacha, David I. Watkins, Benjamin J. Burwitz

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Yellow fever virus (YFV) is a reemerging global health threat, driven by several factors, including increased spread of the mosquito vector and rapid urbanization. Although a prophylactic vaccine exists, vaccine hesitancy, supply deficits, and distribution difficulties leave specific populations at risk of severe YFV disease, as evidenced by recent outbreaks in South America. To establish a treatment for patients with severe YFV infection, we tested 37 YFV-specific monoclonal antibodies isolated from vaccinated humans and identified two capable of potently neutralizing multiple pathogenic primary YFV isolates. Using both hamster and nonhuman primate models of lethal YFV infection, we demonstrate that a …

Molecular Genetic Studies Of Horses, Especially With Reference To Aggrecan And Dwarfism, John Edmund Eberth

Theses and Dissertations--Veterinary Science

This work consists of studies on dwarfism in Miniature horses and a study on breakdowns in Thoroughbreds in relation to gene aggrecan. A correction of the description and designation of D3 dwarf variant in aggrecan (ACAN) from the master’s thesis Chondrodysplasia-like dwarfism in the Miniature horse (2013). Commercial sequencing showed previous sequencing reads presented an artifact and not a single base deletion. Analysis showed a single base missense mutation in exon 8 identified as D3* was the actual cause. Multiple alleles of ACAN associated with chondrodysplastic dwarfism in Miniature horses by Eberth et al. (2018), corrected the …

Use Of Molecular Genetics To Investigate Population Structure And Swayback In Horses, Navid Yousefimashouf

Theses and Dissertations--Veterinary Science

The present research incorporated molecular genetic methods to 1) investigate the genetic basis of Juvenile Onset Lordosis or Swayback in the American Saddlebred horses; and 2) conduct a population genetic study to compare the Persian Kurdish, Persian Arabian and American Thoroughbred horse populations.

Juvenile-onset lordosis, or swayback, is a condition in horses where the conformational topline back curvature drops significantly within the first two years of life. The trait has a higher prevalence in Saddlebreds (5%). Prior research on them quantified the trait using a Measurement of Back Contour (MBC), defining an MBC of >7.0 centimeters as swayback, and8.0) MBC …

Sequencing Antisense Transcriptome Of Populus Through Antisense/Sense Transcript Pair Enrichment, Emma V. Burke

Dissertations, Master's Theses and Master's Reports

Past transcriptome research on plants focused primarily on protein coding genes, and only recently researchers began looking into the non-protein coding regions that may play significant roles in gene regulation. Antisense RNA transcripts that are found naturally in the cell share complementary sequence with sense transcripts and have been shown to regulate expression of their sense counterparts. Since antisense RNA has been largely under-studied and difficult to sequence because of their low relative abundance, new methods are needed to target antisense RNA for efficient genome-wide profiling. To address this gap in methods to efficiently and cost effectively enrich antisense RNA …

White-Tailed Deer In A Winter-Wonderland: Long-Term Deer Yard Use And Methodological Considerations For Ungulate Fecal Dna Metabarcoding, Melanie A. Ottino

Dissertations, Master's Theses and Master's Reports

Northern white-tailed deer (Odocoileus virginianus) mitigate the increased energetic costs of severe winter conditions through obligate migration to densely congregated areas with abundant conifer cover, a behavior referred to as yarding. “Deer yards” in the Western Upper Peninsula (UP) of Michigan are principally located within the reduced snowpack and increased ambient temperature microclimates of densely canopied eastern hemlock (Tsuga canadensis) stands, but specific drivers of long-term site fidelity and utilization are largely uncharacterized. As an important game species of high economic and cultural value and a keystone herbivore with critical impact of plant community composition and structure, identifying winter yarding …

Can Testing The Environment For Severe Acute Respiratory Coronavirus Virus 2 (Sars-Cov-2) Be A Signal For Coronavirus Disease 2019 (Covid-19) Cases Among Nursing Home Staff?, Gabrielle M. Gussin, Raveena D. Singh, Izabela Coimbra Ibraim, Raheeb Saavedra, Thomas T. Tjoa, Micaila Curtis, Kristine P. Nguyen, Ilhem Messaoudi, Susan S. Huang

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Prior to widespread COVID-19 vaccination, nursing homes were required to perform comprehensive weekly testing of staff. After the vaccine became available, testing became symptom-based for vaccinated staff despite continued waves of different severe acute respiratory coronavirus virus 2 (SARS-CoV-2) variants. Nursing homes need pragmatic, affordable strategies to identify SARS-CoV-2–positive staff because financial and job-related pressures drive reluctance to disclose mild symptoms. We sought to determine whether positive environmental samples for SARS-CoV-2 could serve as trigger for comprehensive staff testing in lieu of weekly testing of all staff.