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Although millions of distinct virus species likely exist, only approximately 9000 are catalogued in GenBank's RefSeq database. We selectively enriched for the genomes of circular DNA viruses in over 70 animal samples, ranging from nematodes to human tissue specimens. A bioinformatics pipeline, Cenote-Taker, was developed to automatically annotate over 2500 complete genomes in a GenBank-compliant format. The new genomes belong to dozens of established and emerging viral families. Some appear to be the result of previously undescribed recombination events between ssDNA and ssRNA viruses. In addition, hundreds of circular DNA elements that do not encode any discernable similarities to previously characterized sequences were identified. To characterize these 'dark matter' sequences, we used an artificial neural network to identify candidate viral capsid proteins, several of which formed virus-like particles when expressed in culture. These data further the understanding of viral sequence diversity and allow for high throughput documentation of the virosphere.

Raccoon polyomavirus 1 (RacPyV1) is the suspected cause of an outbreak of fatal brain tumors among raccoons (Procyon lotor) in the western United States. Spleen samples from Georgia raccoons were screened for polyomaviruses. Although RacPyV1 was not detected, a previously unknown polyomavirus, which we designate RacPyV2, was identified and sequenced.

Background The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly transmissible in vaccinated and unvaccinated populations. The dynamics that govern its establishment and propensity toward fixation (reaching 100% frequency in the SARS-CoV-2 population) in communities remain unknown. Here, we describe the dynamics of Omicron at 3 institutions of higher education (IHEs) in the greater Boston area. Methods We use diagnostic and variant-specifying molecular assays and epidemiological analytical approaches to describe the rapid dominance of Omicron following its introduction into 3 IHEs with asymptomatic surveillance programs. Results We show that the establishment of Omicron at IHEs precedes that of the state and region and that the time to fixation is shorter at IHEs (9.5–12.5 days) than in the state (14.8 days) or region. We show that the trajectory of Omicron fixation among university employees resembles that of students, with a 2- to 3-day delay. Finally, we compare cycle threshold values in Omicron vs Delta variant cases on college campuses and identify lower viral loads among college affiliates who harbor Omicron infections. Conclusions We document the rapid takeover of the Omicron variant at IHEs, reaching near-fixation within the span of 9.5–12.5 days despite lower viral loads, on average, than the previously dominant Delta variant. These findings highlight the transmissibility of Omicron, its propensity to rapidly dominate small populations, and the ability of robust asymptomatic surveillance programs to offer early insights into the dynamics of pathogen arrival and spread. [ABSTRACT FROM AUTHOR]

CRISPR guide RNA sequences deriving exactly from natural sequences may not perform optimally in every application. Here we implement and evaluate algorithms for designing maximally fit, artificial CRISPR-Cas13a guides with multiple mismatches to natural sequences that are tailored for diagnostic applications. These guides offer more sensitive detection of diverse pathogens and discrimination of pathogen variants compared with guides derived directly from natural sequences and illuminate design principles that broaden Cas13a targeting., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Celiac disease (CD) is an autoimmune condition presenting with a wide variety of nonspecific gastrointestinal symptoms. It can be difficult to diagnose due to the vagueness of complaints such as diarrhea, anemia due to malabsorption, vitamin or electrolyte deficiencies, and/or failure to thrive. This condition is characterized by a sensitivity to ingested gluten-containing compounds. Blood tests can be used for screening, though confirmatory testing by a small intestine biopsy is needed for diagnosis. Viral infections can trigger autoimmune conditions in individuals. It is possible that viral infections, such as Ebsetein-Barr virus(EBV) or Cytomegalovirus (CMV), can trigger the clinical presentation of celiac disease in certain individuals with genetic predispositions. Early recognition of celiac disease is important to prevent both short and long-term complications and improve the quality of life for the individual. Here, we discuss a case where the patient developed celiac disease only months after a diagnosis of mononucleosis., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Welch et al.)

The COVID-19 pandemic, and the recent rise and widespread transmission of SARS-CoV-2 Variants of Concern (VOCs), have demonstrated the need for ubiquitous nucleic acid testing outside of centralized clinical laboratories. Here, we develop SHINEv2, a Cas13-based nucleic acid diagnostic that combines quick and ambient temperature sample processing and lyophilized reagents to greatly simplify the test procedure and assay distribution. We benchmarked a SHINEv2 assay for SARS-CoV-2 detection against state-of-the-art antigen-capture tests using 96 patient samples, demonstrating 50-fold greater sensitivity and 100% specificity. We designed SHINEv2 assays for discriminating the Alpha, Beta, Gamma and Delta VOCs, which can be read out visually using lateral flow technology. We further demonstrate that our assays can be performed without any equipment in less than 90 minutes. SHINEv2 represents an important advance towards rapid nucleic acid tests that can be performed in any location.

Several immunodeficiencies are associated with high susceptibility to persistent and progressive human papillomavirus (HPV) infection leading to a wide range of cutaneous and mucosal lesions. However, the HPV types most commonly associated with such clinical manifestations in these patients have not been systematically defined. Here, we used virion enrichment, rolling circle amplification, and deep sequencing to identify circular DNA viruses present in skin swabs and/or wart biopsy samples from 48 patients with rare genetic immunodeficiencies, including patients with warts, hypogammaglobulinemia, infections, myelokathexis (WHIM) syndrome, or epidermodysplasia verruciformis (EV). Their profiles were compared with the profiles of swabs from 14 healthy adults and warts from 6 immunologically normal children. Individual patients were typically infected with multiple HPV types; up to 26 different types were isolated from a single patient (multiple anatomical sites, one time point). Among these, we identified the complete genomes of 83 previously unknown HPV types and 35 incomplete genomes representing possible additional new types. HPV types in the genus Gammapapillomavirus were common in WHIM patients, whereas EV patients mainly shed HPVs from the genus Betapapillomavirus. Preliminary evidence based on three WHIM patients treated with plerixafor, a leukocyte mobilizing agent, suggest that longer-term therapy may correlate with decreased HPV diversity and increased predominance of HPV types associated with childhood skin warts. IMPORTANCE Although some members of the viral family Papillomaviridae cause benign skin warts (papillomas), many human papillomavirus (HPV) infections are not associated with visible symptoms. For example, most healthy adults chronically shed Gammapapillomavirus ( Gamma ) virions from apparently healthy skin surfaces. To further explore the diversity of papillomaviruses, we performed viromic surveys on immunodeficient individuals suffering from florid skin warts. Our results nearly double the number of known Gamma HPV types and suggest that WHIM syndrome patients are uniquely susceptible to Gamma HPV-associated skin warts. Preliminary results suggest that treatment with the drug plerixafor may promote resolution of the unusual Gamma HPV skin warts observed in WHIM patients.