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Genetic Analysis of Asymptomatic Antinuclear Antibody Production.

OBJECTIVE: Antinuclear antibodies (ANA) are detected in up to 14% of the population, and many individuals with ANA are asymptomatic. The literature on the genetic contribution to asymptomatic ANA positivity is limited. In this study, we aimed to perform a genome-wide association study of asymptomatic ANA positivity in multiple populations. METHODS: Asymptomatic individuals who were either ANA positive or ANA negative from the All of Us Research Program were included in this study, selecting those with an ANA test performed by immunofluorescence and no evidence of autoimmune disease. Imputation was performed, and a multipopulation meta-analysis including approximately 6 million single-nucleotide polymorphisms (SNPs) was conducted. Genome-wide SNP-based heritability was estimated using the Genome-wide Complex Trait Analysis&#xa0;software. A cumulative genetic risk score for lupus was constructed using previously reported genome-wide significant loci. RESULTS: A total of 1,955 asymptomatic ANA positive and 3,634 asymptomatic ANA negative individuals across three populations were included. The multipopulation meta-analysis revealed SNPs with a suggestive association (P <1 &#xd7; 10-5) across 8 different loci, but no genome-wide significant loci were identified. A gene variant upstream of HLA-DQB1, (rs17211748, P = 1.4 &#xd7; 10-6, odds ratio 0.82, 95% confidence interval 0.76-0.89), showed the most significant association. The heritability of asymptomatic ANA positivity was estimated to be 24.9%. Individuals who were asymptomatic and ANA positive did not exhibit increased cumulative genetic risk for lupus compared with individuals who were ANA negative. CONCLUSION: ANA production is not associated with significant genetic risk and is primarily determined by environmental factors.

Humans

Comparison of phylogenetic metrics of transmission in symptomatic and asymptomatic tuberculosis.

BACKGROUND: Understanding drivers of Mycobacterium tuberculosis (Mtb) transmission remains a critical challenge in high-burden settings. Tuberculosis control efforts traditionally target symptomatic individuals, yet the role of asymptomatic cases in sustaining transmission is increasing recognized. METHODS: We conducted a genomic and epidemiological analysis of Mtb isolates collected in Mato Grosso do Sul, Brazil, between 2008 and 2024. From 2017 to 2022, active case finding was performed in three of the state's largest prisons, whereby sputum was collected from individuals irrespective of symptoms and tested by GeneXpert and culture. We evaluated several metrics of recent transmission from symptomatic and asymptomatic individuals, including phylogenetic clustering, Time-scaled Haplotype Density (THD), Local Branching Index (LBI), and transmission probabilities inferred using the Bayesian Reconstruction and Evolutionary Analysis of Transmission Histories (BREATH). FINDINGS: We sequenced 2,362 Mtb strains, of which 3.5% (115/2,362) were resistant to at least one drug, and 0.6% (16/2,362) were multi-drug resistant. Most strains were lineage 4, and 78.2% of all isolates were part of a genomic cluster. Among 2,362 individuals with tuberculosis, 1,137 were incarcerated at the time of diagnosis. Among these, 505 were identified through active case finding: 277 had symptomatic disease and 228 had asymptomatic tuberculosis. There was no significant difference in phylogenetic clustering proportion (77% vs. 85%; p= 0.816), THD (median 0.50 vs. 0.39; p = 0.120), or LBI (median 0.00863 vs. 0.00871; p = 0.086) between symptomatic and asymptomatic individuals. Bayesian transmission trees revealed no significant difference in the number of secondary infections inferred from symptomatic compared with asymptomatic individuals (p = 0.56). These findings were consistent across genomic clusters and robust to model assumptions. INTERPRETATION: We identified no differences in transmission from symptomatic compared with asymptomatic individuals, using several genomic measures of transmission, underscoring the substantial contribution that asymptomatic tuberculosis makes to transmission at the population level.

Asymptomatic

Comparison of phylogenetic metrics of transmission between symptomatic and asymptomatic tuberculosis in individuals who were incarcerated in Brazil in 2008-24: a retrospective genomic epidemiology study.

BACKGROUND: Tuberculosis control efforts have traditionally targeted symptomatic individuals; however, the role of asymptomatic cases in sustaining transmission is increasingly recognised. We aimed to quantify the contribution of asymptomatic tuberculosis to recent transmission using genomic and epidemiological data from a high-transmission setting. METHODS: We conducted a retrospective genomic epidemiology study of Mycobacterium tuberculosis isolates collected in Mato Grosso do Sul, Brazil, between Aug 25, 2008, and March 19, 2024. Available isolates underwent whole-genome sequencing. Demographic, clinical, incarceration history, and laboratory metadata were obtained from surveillance records. From Jan 1, 2017, to March 19, 2024, active case finding was conducted in the state's three largest prisons (all male-only facilities), during which sputum samples were collected from individuals irrespective of symptoms and tested using GeneXpert and culture. Comparisons of transmission between individuals with and without symptoms were restricted to individuals who were incarcerated and were identified through active case finding and for whom high-quality, M tuberculosis lineage 4 genomes were available. Metrics of recent transmission included phylogenetic clustering, time-scaled haplotype density (THD), local branching index (LBI), and transmission probabilities inferred using Bayesian Reconstruction and Evolutionary Analysis of Transmission Histories. FINDINGS: 4448 tuberculosis cases were notified in Mato Grosso do Sul in 2008-24. After excluding cases for which M tuberculosis isolates were not available or had low sequencing quality, who had contaminated cultures or mixed infection, or who were infected with non-lineage 4 M tuberculosis, we included 2362 lineage 4 M tuberculosis isolates with high-quality genome sequences. 1849 (78&#xb7;3%) of 2362 isolates were part of a genomic cluster. Among 2362 individuals with tuberculosis, 1137 (48&#xb7;1%) were incarcerated at diagnosis. Of these individuals, 505 were identified through active case finding in three male-only prisons. The median age was 30 years (IQR 25-37); 304 (60&#xb7;2%) had mixed ethnicity, 90 (17&#xb7;8%) were White, 56 (11&#xb7;1%) were Black, 13 (2&#xb7;6%) were Indigenous, and six (1&#xb7;2%) were Asian. 277 (54&#xb7;9%) had symptomatic disease and 228 (45&#xb7;1%) had asymptomatic tuberculosis. There were no significant differences between symptomatic and asymptomatic individuals in phylogenetic clustering (213 [76&#xb7;9%] of 277 vs 195 [85&#xb7;5%] of 228; p=0&#xb7;37), THD (median 0&#xb7;39 [IQR 0&#xb7;06-0&#xb7;62] vs 0&#xb7;50 [0&#xb7;09-0&#xb7;65]; p=0&#xb7;12), or LBI (0&#xb7;00863 [0&#xb7;00810-0&#xb7;00988] vs 0&#xb7;00871 [0&#xb7;00829-0&#xb7;01020]; p=0&#xb7;088). Bayesian transmission trees showed no significant difference in the number of secondary infections inferred from symptomatic compared with asymptomatic individuals (p=0&#xb7;56). These findings were consistent across genomic clusters and robust to model assumptions. INTERPRETATION: We identified no differences in transmission between individuals who were symptomatic and those who were asymptomatic using multiple genomic measures. In this high-transmission setting, where systematic screening is implemented, our findings indicate that asymptomatic tuberculosis substantially contributes to tuberculosis transmission at the population level. These results suggest that symptom-based case detection alone is likely to be insufficient to interrupt transmission and highlight the importance of expanded screening strategies in high-risk populations. FUNDING: US National Institutes of Health and the Brazilian National Research Council (CNPq).

Humans

Clinical Phenotype and Prognosis of Asymptomatic Patients With Transthyretin Cardiac Amyloid Infiltration.

IMPORTANCE: Patients with transthyretin (ATTR) cardiac amyloid infiltration are increasingly diagnosed at earlier disease stages with no heart failure (HF) symptoms and a wide range of cardiac amyloid infiltration. OBJECTIVE: To characterize the clinical phenotype and natural history of asymptomatic patients with ATTR cardiac amyloid infiltration. DESIGN, SETTING, AND PARTICIPANTS: This cohort study analyzed data of all patients at 12 international centers for amyloidosis from January 1, 2008, through December 31, 2023. Inclusion criteria were asymptomatic ATTR cardiac amyloid infiltration, defined as an absence of HF history, HF signs and symptoms, diuretic therapy, and plasma cell dyscrasia with evidence of myocardial uptake on bone scintigraphy. If plasma cell dyscrasia was present, histologic confirmation of ATTR amyloid was required. EXPOSURE: Asymptomatic ATTR cardiac amyloid infiltration. MAIN OUTCOMES AND MEASURES: The primary outcomes were all-cause and cardiovascular (CV) mortality. The secondary outcomes were unplanned HF hospitalization, unplanned CV-related hospitalization, and a composite outcome of CV mortality and HF hospitalization. RESULTS: The study comprised 485 patients with asymptomatic ATTR cardiac amyloid infiltration (mean [SD] age, 74.9 [9.9] years, 85.8% male, 112 [23.1%] with hereditary ATTR amyloidosis), with 369 (76.1%) having grade 2 or 3 and 116 (23.9%) having grade 1 cardiac uptake at baseline. Patients with grade 2 or 3 uptake exhibited significantly more cardiac functional and structural abnormalities vs patients with grade 1 uptake. At 3 years, compared with grade 1 uptake, patients with grade 2 or 3 uptake had greater development of HF (54.3% [95% CI, 47.7%-61.3%] vs 23.1% [95% CI, 14.8%-35.1%]), greater outpatient diuretic initiation and N-terminal pro-B-type natriuretic peptide progression (35.0% [95% CI, 28.0%-43.2%] vs 12.4% [95% CI, 6.3%-23.7%]), and greater HF hospitalization (8.7% [95% CI, 5.9%-12.9%] vs 0%) and unplanned CV hospitalization (20.0% [95% CI, 15.7%-25.3%] vs 4.3% [95% CI, 1.6%-11.3%]). Over a median follow-up of 37 months (IQR, 20-64 months), the all-cause death rate was similar between patients with grade 1 vs 2 and 3 uptake; however, those with grade 2 or 3 compared with grade 1 uptake had a significantly higher risk of CV mortality (unadjusted hazard ratio, 5.30; 95% CI, 1.92-14.65). CONCLUSIONS AND RELEVANCE: This study shows that asymptomatic ATTR cardiac amyloid infiltration encompasses a wide spectrum of disease severity, with patients with grade 2 or 3 cardiac uptake experiencing an increased rate of CV events and CV mortality and patients with grade 1 uptake experiencing a lower CV event rate and predominantly non-CV mortality. These findings support the use of disease-modifying treatments in asymptomatic patients with grade 2 or 3 uptake and highlight the need of large-scale studies to assess their role in grade 1 uptake.

Humans

A pan-beta-coronavirus vaccine bearing conserved and asymptomatic B- and T-cell epitopes protects against highly pathogenic Delta and highly transmissible Omicron SARS-CoV-2 variants.

Over the last five years of the COVID-19 pandemic, the repetitive mutations and deletions in the SARS-CoV-2 genome, primarily targeting the Spike gene, resulted in the emergence of multiple viral variants and sub-variants. The non-updated mismatched Spike-based sub-unit vaccines are less effective due to the ability of these SARS-CoV-2 variants and sub-variants to evade vaccine-induced humoral immunity. To reduce reliance on neutralizing antibodies and prevent potential mismatches between circulating variants, sub-variants, and the vaccines, we have identified highly conserved Spike and non-Spike viral epitopes associated with protective asymptomatic B- and T-cell immune responses, respectively. We demonstrated that unvaccinated asymptomatic patients with COVID-19 recognized these conserved B- and T-cell epitopes. Using the mRNA-LNP-based antigen delivery system, we developed a multi-epitope vaccine that incorporates the conserved B-cell epitopes, CD4+ T-cell epitopes, and CD8+ T-cell epitopes. To assess the efficacy of this "asymptomatic" multi-epitope vaccine, we used the HLA-A*02:01/HLA-DRB1*&#x2009;01:01-hACE-2 triple transgenic mouse model. We demonstrated that this "asymptomatic" multi-epitope vaccine conferred robust protection against infection and disease caused by the SARS-CoV-2 Delta (B.1.617.2) and Omicron (XBB.1.5) variants as assessed by: (i) prevention of weight loss, (ii) reduction of virus replication, and (iii) lung pathology. This protection was associated with: (i) strong antibody responses; and (ii) high frequency of anti-viral IFN-&#x3b3;-producing CD4+ and CD8+ T-cells. These findings illustrate the possibility of developing a pan-beta-coronavirus vaccine to induce broad-spectrum protective immunity against SARS-CoV-2 variants and sub-variants by targeting highly conserved "asymptomatic" B- and T-cell epitopes identified from both structural and non-structural viral proteins.

Epitopes, T-Lymphocyte

Assessment of differentially culturable tubercle bacteria assays for the detection of tuberculosis infection in asymptomatic household contacts and the implications for intra-household transmission: a longitudinal cohort study.

BACKGROUND: Conventional culture methods for tuberculosis diagnosis miss differentially culturable tubercle bacteria (DCTB), which grow only in liquid assays supplemented with growth-enhancing factors. This limitation, combined with inadequate contact tracing and screening, often fails to identify asymptomatic individuals, with live bacilli detectable by enhanced culture methods. This shortfall results in undiagnosed reservoirs of bacteria, potentially fuelling ongoing transmission. In this study, we aimed to investigate whether DCTB assays provide greater sensitivity by detecting more Mycobacterium tuberculosis infections than conventional culture and whether this enhanced detection improves the resolution of intrahousehold transmission mapping. In addition, we sought to evaluate whether DCTB populations can progress to conventional culture positivity, thereby highlighting their clinical and epidemiological relevance. METHODS: In this prospective observational longitudinal cohort study, drug-susceptible or rifampicin-resistant tuberculosis index participants aged 12 years or older, were recruited from primary healthcare clinics from two South African districts. Inclusion criteria were informed consent, Xpert MTB/RIF Ultra-positive results, tuberculosis symptoms (>2 weeks), provision of baseline samples, at least one consenting household contact, and documented HIV status. Household contacts of the index patients and control households were also recruited. Sputum specimens were collected at baseline and 2, 4, 8, 12, and 16 months from the index participants and household contacts. Samples were analysed by conventional mycobacterial growth indicator tube (MGIT) culture, and colony-forming unit assays to identify viable bacteria. Enhanced culture to detect DCTB involved serial dilution of sputum in liquid culture, supplemented with M tuberculosis culture filtrate as a source of growth stimulatory factors. Whole-genome sequencing (WGS) of cultured isolates was performed to trace household transmission. FINDINGS: Between June 1, 2020, and Feb 6, 2024, 293 index participants (183 [62%] male), 701 household contacts (453 [65%] female), and 122 control participants (67 [55%] female) were enrolled. At baseline, 249 (85%) of 293 index participants and 110 (16%) of 701 household contact sputum samples were positive for M tuberculosis by MGIT conventional culture. For baseline MGIT-negative specimens, DCTB assays detected M tuberculosis in an additional 21 (7%) of 293 index participants and 26 (4%) of 701 household contacts. Over 16 months of follow-up, DCTB assays identified 61 (8&#xb7;7%) of 701 additional tuberculosis-positive household contacts not detected by conventional culture. WGS-guided transmission mapping using conventional culture identified transmission in 16 (15%) of 104 households, whereas DCTB assays detected an additional 19 (18%) of 104 transmission events. No evidence of intrahousehold transmission was found in the remaining 69 (66%) of 104 tuberculosis-positive households. Over the 16-month follow-up period, conventional culture identified 233 positive household contacts, of which 195 (84%) were asymptomatic. DCTB assays detected an additional 94 cases of M tuberculosis positivity in household contacts, of which 79 (84%) were asymptomatic. In control households, tuberculosis prevalence at baseline was two (2%) of 122, with an additional three (3%) of 122 identified during follow-up. INTERPRETATION: DCTB assays provide substantial value by detecting asymptomatic individuals missed by conventional culture, revealing a potentially important reservoir of subclinical infection, which could sustain transmission. In addition, DCTB detection uncovers transmission linkages missed by conventional culture, providing a more comprehensive understanding of M tuberculosis transmission dynamics and highlighting the need to incorporate enhanced culture methods into diagnostic and surveillance strategies, to strengthen early case identification and tuberculosis control efforts. FUNDING: National Institutes of Health.

Humans

A viral clonality evenness score to predict progression to adult T-cell leukaemia in asymptomatic carriers of human T-lymphotropic virus type 1 in Japan: a retrospective longitudinal cohort study.

BACKGROUND: Adult T-cell leukaemia/lymphoma (ATL) is a highly aggressive T-cell malignancy that occurs in approximately 2-7% of individuals with human T-lymphotropic virus type 1 (HTLV-1), after decades of asymptomatic infection. To address the urgent need for predictive biomarkers to identify asymptomatic carriers of HTLV-1 at high risk of progression to ATL, we aimed to evaluate viral clonality sequencing as a potential tool for risk stratification. METHODS: This retrospective longitudinal cohort study involved HTLV-1 carriers enrolled in the Joint Study on Predisposing Factors of ATL Development, a nationwide cohort study initiated in Japan in 2002. Participants were selected from this cohort on the basis of their baseline proviral load at the time of enrolment as an asymptomatic carrier, length of follow-up, and clinical outcome. The cohort was subdivided into three subgroups: the first comprising HTLV-1 carriers who developed ATL, the second comprising carriers with high proviral load (&#x2265;4%) who did not progress to ATL, and the third comprising carriers with low proviral load (<4%) who did not progress to ATL. DNA extracted from peripheral blood mononuclear cells collected at enrolment and at least one follow-up visit was analysed by HTLV-1 clonality sequencing and the proviral load was quantified. We calculated a viral clonality evenness (VCE) score, based on the Shannon Evenness Index, to quantify the uniformity of the clonal distribution of samples, for which 0 represents a perfectly monoclonal architecture and 1 indicates a completely polyclonal landscape. We then estimated the performance of proviral load thresholds and VCE scoring to classify the risk of progression to ATL using the area under the receiver operating characteristic curve (AUC), the accuracy, and Matthews correlation coefficient. VCEs were compared between participant subgroups with the Wilcoxon rank sum test. FINDINGS: 56 participants followed up by JSPFAD between Feb 6, 2003, and July 19, 2022, were included in this study: 17 who progressed to ATL (mean follow-up 8&#xb7;3 years [SD 4&#xb7;0]), 18 who had a high proviral load and did not progress to ATL (9&#xb7;7 years [3&#xb7;4]), and 21 who had a low proviral load and did not progress to ATL (7&#xb7;5 years [3&#xb7;0]). Clonality sequencing of samples from 39 participants who did not progress to ATL revealed hundreds to thousands of HTLV-1 integration sites at both timepoints, corresponding to multiple clones of low and uniform abundance, and these participants had high VCE scores (&#x2265;0&#xb7;694) at baseline. By contrast, most participants (14 of 17) who progressed to ATL had a single predominant clone or two to four predominant clones at both timepoints, and lower VCE scores (<0&#xb7;694) at baseline than those who did not progress (p<0&#xb7;0001). AUCs were very similar for proviral load thresholds (91 [95% CI 80-98]) and VCE scoring (91 [78-100]), although when using methods that give equal weight to every individual, VCE scoring outperformed proviral load thresholds in predicting progression to ATL (accuracy: proviral load 0&#xb7;76 [95% CI 0&#xb7;76-0&#xb7;77], VCE scoring 1&#xb7;00 [0&#xb7;99-1&#xb7;00]; Matthews correlation coefficient: proviral load 0&#xb7;23 [95% CI 0&#xb7;19-0&#xb7;24], VCE scoring 0&#xb7;91 [0&#xb7;80-1&#xb7;00]). Prediction based on VCE scoring indicated no false positives, compared with 20% when using proviral load, although VCE scoring yields a greater number of false negatives (0&#xb7;3% vs 0&#xb7;1%). INTERPRETATION: The implementation of VCE scoring in clinical practice could inform early pre-emptive therapeutic interventions, exclusively targeting individuals with HTLV-1 at high risk and aiming to prevent progression to aggressive, treatment-refractory disease. Further validation, including independent confirmation of the performance of VCE scoring in multiple populations and the characterisation of its temporal dynamics, will be crucial to determine its clinical utility and potential integration into care pathways. FUNDING: Association Jules Bordet, FNRS-T&#xe9;l&#xe9;vie, FCC, WALInnov, FLF, JSPS-KAKENHI, and CoBiA.

Humans

Antimicrobial resistance in Staphylococcus pseudintermedius isolated from asymptomatic and symptomatic dogs in Montevideo, Uruguay: characterization of MRSP strains and genetic determinants of resistance.

Staphylococcus pseudintermedius&#xa0;is a common opportunistic pathogen in dogs and an increasing concern in veterinary medicine due to rising antimicrobial resistance, particularly to methicillin. This study aimed to characterize resistance profiles and genetic mechanisms in isolates from healthy and diseased dogs in Montevideo, Uruguay. A total of 133 isolates was analyzed (83 from clinical infections and 50 from asymptomatic carriers). Antimicrobial susceptibility was assessed by disk diffusion following veterinary guidelines. Resistance genes and SCCmec types were detected by PCR. Ten representative isolates underwent whole genome sequencing. High resistance rates were observed for penicillin (81%), erythromycin (49.6%), and clindamycin (45%). Overall, 48.9% of isolates were multidrug-resistant. Phenotypic resistance to oxacillin was detected in 26% of isolates; however, 23% carried mecA gene and were therefore classified as genotypic MRSP. These isolates were more frequent among dogs with clinical infections. These strains showed higher resistance to all antimicrobials tested. SCCmec type V was the most prevalent, and greater genetic diversity was found among isolates from symptomatic dogs. Genomic analysis revealed circulating strains of unassigned sequence types (STs), a variety of resistance genes within specific lineages, the circulation of SCCmec XIV cassette carrying strains, and an Oxacillin-susceptible Methicillin-resistant Staphylococcus pseudintermedius (OS-MRSP) isolate. These findings demonstrate the clinical and epidemiological relevance of&#xa0;S. pseudintermedius&#xa0;in Uruguay and the role of asymptomatic dogs as reservoirs of resistant strains. The results emphasize the need for surveillance, prudent antimicrobial use, and integrated control strategies within a One Health framework.

Animals

Ossification variants of the distal femoral condyle: longitudinal 3&#xa0;T MRI evidence of progression to juvenile osteochondritis dissecans in asymptomatic siblings of patients with JOCD.

OBJECTIVE: Ossification variants (OVs) of the femoral condyles are traditionally regarded as benign developmental findings distinct from juvenile osteochondritis dissecans (JOCD). We aimed to characterize the longitudinal MRI behavior of OVs and JOCD lesions in asymptomatic siblings of JOCD patients. MATERIALS AND METHODS: In this HIPAA-compliant longitudinal pilot study, seven asymptomatic siblings of JOCD patients underwent serial 3&#xa0;T bilateral knee MRI. Two fellowship-trained musculoskeletal radiologists independently assessed 56 studies for bone marrow edema, lesion location, and MRI-defined category (OV or JOCD). RESULTS: OV and MRI-defined JOCD lesions were identified in 21 of 28 condyles (75%, 95% CI: 56.6-87.3%), while 7 condyles (25%, 95% CI: 12.7-43.4%) remained normal throughout follow-up. Six condyles demonstrated MRI-defined JOCD lesions at one or more timepoints. Three OV lesions evolved over time: two progressed to MRI-defined JOCD but remained clinically silent, and one progressed from OV to MRI-defined JOCD and subsequently to clinically manifest JOCD requiring surgery. Using Generalized Linear Mixed model, a statistically significant association was found between bone marrow edema and MRI-defined category (F&#x2009;=&#x2009;31.73, p&#x2009;<&#x2009;0.001). OV lesions showed absent or trace edema, whereas JOCD showed definite edema. Inter-reader agreement using Cohen's Kappa was moderate to substantial between the radiologists (&#x3ba;&#x2009;=&#x2009;0.479-0.739, 95% CI: 0.314-0.633, 0.644-0.845, p&#x2009;<&#x2009;0.001). CONCLUSIONS: In siblings of patients with JOCD, OV lesions are common and may represent dynamic MRI phenotypes along a continuum of epiphyseal ossification abnormalities, with occasional progression to MRI-defined JOCD and rare progression to clinically manifest JOCD.

Humans

Multicancer Detection Tests for Population-Wide Screening of Asymptomatic Individuals: A Systematic Review.

PURPOSE: Multicancer detection (MCD) tests aim to detect different cancer types using a single test. However, evidence on their potential for screening asymptomatic populations remains limited. We consolidated evidence from prospective cohort studies evaluating blood-based MCD tests in primarily asymptomatic adults to contextualize upcoming randomized controlled trial results. MATERIALS AND METHODS: We updated and extended a prior review (to September 2023), conducting comprehensive Medline/Embase searches to February 1, 2026. Key outcomes included cancers detected and not detected by MCD tests, false-positive MCD tests, and diagnostic investigation pathways. Risk of bias (RoB) was assessed using a modified Quality Assessment of Diagnostic Accuracy Studies-2 tool. RESULTS: From 2,723 screened records (244 previously shortlisted to 2023, 2,479 records for 2023-2026), we included 18 articles (12 studies, nine MCD tests); of these, 11 articles had not appeared in prior reviews. Cancer detection rates varied widely between studies, for example, new MCD-test-detected invasive cancers diagnosed &#x2264;12 months post-test ranging from 18.8 (95% CI, 11.0 to 30.1) to 43.8 (95% CI, 29.4 to 62.8) per 10,000 tested, with MCD-test-detected invasive stage I to II cancers ranging from 9.0 (95% CI, 4.2 to 17.2) to 21.0 (95% CI, 11.6 to 35.5) per 10,000 tested. False-positives exceeded MCD-test-detected cancers (eg, approximately 1.6-fold in PATHFINDER, 1.5-fold K-DETEK, 4.2-fold DETECT-A, 8.1-fold SeekInCare studies). Diagnostic investigation pathways were prespecified/suggested in four of eight interventional studies. Where reported, the median time to diagnostic resolution varied from <0.1 months to 4 months for MCD-test-detected cancers, with substantially higher 75th percentiles (3.1-7 months), and similar patterns were observed for false-positive MCD tests. No study was judged to have overall low RoB. CONCLUSION: Substantial heterogeneity in cancer yield metrics likely reflects differences in MCD technologies, diagnostic pathways, follow-up duration, and background standard-of-care screening. Long-term follow-up, randomized trials, fully-paired test comparisons, and implementation research are essential to determine the potential of MCD tests for population screening.

Journal Article

Asymptomatic SARS-CoV-2 Infection: Association Involving the HLA-B*15 Allele Group in Brazilian Individuals.

The aim of this study was to investigate the influence of HLA-A, -B and -C polymorphisms on the clinical course of SARS-CoV-2 infection and on the progression of COVID-19 in a population from southeastern Brazil. This study included 478 unvaccinated individuals. Of these, 369 were hospitalised with critical/severe (n&#x2009;=&#x2009;309) or moderate/mild (n&#x2009;=&#x2009;60) symptoms, and 109 were asymptomatic. The control group consisted of 150 volunteer bone marrow donors, recruited in the pre-pandemic period. The HLA-B*15 allele group (adjusted p value&#x2009;<&#x2009;0.001) was associated with a protective factor against symptomatic infection. Investigating the effects of the distribution of HLA alleles on susceptibility and resistance to SARS-CoV-2 may provide a better understanding of the clinical course of infection in different geographical regions.

Humans

Prevalence and persistence of high-risk HPV genotypes in unvaccinated asymptomatic women: a six-year study in Peru.

OBJECTIVE: This study was to determine the frequency of HPV-hr and describe the distribution by categories (HPV16, HPV18, HPV-hr non16/18) among unvaccinated asymptomatic women in Peru over a 6-year period (2013-2018). In addition, the disease clearance rate is assessed in a percentage of cases. RESULTS: Of the 6,665 samples, 2,240 (33.6%) tested positive for HPV. Among the positive cases, single-genotype infections were caused by HPV-16 (14.8%), followed by HPV-18 (2.2%) and clustered high-risk HPV (HR-HPV) genotypes (66.7%). Multiple HPV-16 infections were more common than HPV-18 infections. In addition, 22 cases (1%) presented with infection with HPV-16, HPV-18, and HR-HPV genotypes. A subset of 116 samples from patients with 1 to 2 years of follow-up was analyzed further. Clearance rates were high, at 68.8% for HPV-16 infections and 67.5% for HR-HPV infections. However, the elimination rate of multiple infections with HPV-16 and HR-HPV genotypes was slightly lower, at 55.6%.

Prevalence

Development and validation of a serum peptidomic signature for early detection of asymptomatic ovarian cancer: A multi-center prospective study.

Early detection of asymptomatic ovarian cancer (asym-OC) remains a critical challenge, the failure of which underlies its high mortality. Performing serum peptidomic profiling of 843 participants in the cohort SOCFCP, we distill 1,081 initial features into a 7-marker panel for asym-OC detection via a biology-informed machine-learning (ML)-based feature selection strategy. Three markers significantly revert toward non-OC levels after surgery. Integrating the panel with age, CA125, and HE4, we develop and externally validate (n = 159) a LightGBM model, ProMS+. For early-stage OC detection, ProMS+ shows a specificity of 92.6% at 95.0% sensitivity, outperforming CA125 (44.7%), HE4 (11.2%), and Risk of Ovarian Malignancy Algorithm (ROMA) (24.0%), with an area under the curve (AUC) of 0.993. In a simulated high-risk population (n = 100,000; OC prevalence = 1%), ProMS+ yields a high AUC (0.983) and a higher positive predictive value than CA125, HE4, and Age + CA125 + HE4 combined model (0.201 vs. 0.027, 0.090, and 0.064). ProMS+ offers a promising, non-invasive, and interpretable approach for the early detection of asym-OC.

Humans

Untargeted metabolomics in a prospective cross-sectional observational study reveals differences in plasma and cerebrospinal fluid between asymptomatic neurosyphilis and serofast syphilis.

Asymptomatic neurosyphilis (ANS), a diagnostically elusive complication of Treponema pallidum infection, necessitates invasive cerebrospinal fluid (CSF) analysis for detection. This study investigated metabolic differences between patients with ANS and those with serofast syphilis. Using untargeted metabolomics, we analyzed plasma and CSF from 15 patients with ANS, 15 patients with serofast syphilis, and 16 healthy controls via liquid chromatography-mass spectrometry. Univariate statistical analyses identified differential metabolites, followed by pathway enrichment through Kyoto encyclopedia of genes and genomes enrichment analysis and biomarker evaluation. Plasma analysis identified dysregulated tryptophan metabolism as a central feature in ANS, with key alterations in 4-(2-aminophenyl)-2,4-dioxobutanoic acid and 2-formylaminobezaldehyde. Comparative analysis further distinguished ANS through perturbations in inositol phosphate metabolism in both plasma and CSF. Spearman correlation analysis identified positive associations of the plasma biomarkers 1D-myo-inositol-1,3,4,6-tetrakisphosphate, inositol-1,3-bisphosphate, 4-(2-aminophenyl)-2,4-dioxobutanoic acid, and 2-formylaminobezaldehyde with CSF total protein. Our findings suggest that dysregulation in tryptophan and inositol phosphate metabolism may play an important role in ANS pathogenesis, warranting further confirmatory studies.

Humans

Plasma Proteomic Profiles of Pediatric Patients With Human Herpesvirus 6B Encephalitis Following Umbilical Cord Blood Transplantation.

Human herpesvirus 6B (HHV-6B) encephalitis is a rare but severe complication of hematopoietic cell transplantation. This study investigated the pathogenesis of HHV-6B encephalitis by comparing plasma proteomic profiles of four pediatric patients with HHV-6B encephalitis to three with asymptomatic HHV-6B reactivation following umbilical cord blood transplantation (UCBT). Plasma proteomic profiling was conducted using liquid chromatography-mass spectrometry. Overall, 260 proteins were identified and quantified in plasma samples. At the onset of HHV-6B encephalitis and asymptomatic reactivation, 20 and 24 proteins, respectively, were significantly upregulated compared to their respective pre-onset levels. Of these, 11 proteins were uniquely upregulated in HHV-6B encephalitis. S100-A9 and S100-A8 were the most and second-most upregulated proteins in HHV-6B encephalitis, respectively. Elevated plasma S100A8/A9 heterodimer levels were confirmed via enzyme-linked immunosorbent assay in three of the four patients with HHV-6B encephalitis. Pathway analysis identified neutrophil degranulation as the most enriched category among upregulated proteins in HHV-6B encephalitis. Additionally, proteins related to the protein-lipid complex remodeling pathway were more prominently upregulated in HHV-6B encephalitis than in asymptomatic reactivation. Proteomic analysis revealed distinct plasma protein profiles between HHV-6B encephalitis and asymptomatic HHV-6B reactivation in pediatric UCBT recipients. The inflammatory response mediated by S100A8/A9 proteins may play a critical role in the pathogenesis of HHV-6B encephalitis. These findings indicate that proteomic analysis may provide novel insights into the host response to HHV-6B reactivation and the subsequent development of HHV-6B encephalitis.

Humans

Vaccine efficacy of NVX-CoV2373 against SARS-CoV-2 infection in adolescents in the USA: an ancillary study to a phase 3, observer-blinded, randomised, placebo-controlled trial.

BACKGROUND: Although existing COVID-19 vaccines are known to be highly effective against severe disease and death, data are needed to assess their ability to reduce SARS-CoV-2 infection. We aimed to estimate the efficacy of the NVX-CoV2373 protein subunit vaccine against SARS-CoV-2 infection, regardless of symptoms, among adolescents. METHODS: We performed an ancillary observational study (SNIFF) to the phase 3, observer-blinded, randomised, placebo-controlled PREVENT-19 trial that assessed vaccine efficacy against symptomatic COVID-19 in the USA. Participants in the PREVENT-19 trial included healthy adolescents aged 12-17&#xa0;years and with no history of laboratory-confirmed SARS-CoV-2 infection. They were randomly assigned (2:1) to receive either the NVX-CoV2373 (Novavax, Gaithersburg, MD, USA) vaccine (immediate NVX-CoV2373 group) or placebo (delayed NVX-CoV2373 group) on days 0&#xa0;and 21 (initial series). After 2&#xa0;months, in a crossover series, participants received two doses, 21&#xa0;days apart, of the intervention that they did not receive in their initial series. Participants at 47 of the PREVENT-19&#xa0;sites were invited to participate in the SNIFF study and self-collect nasal swabs at home twice weekly for SARS-CoV-2 testing to assess vaccine efficacy against SARS-CoV-2 infection. This primary outcome was defined as the first identification of SARS-CoV-2 detected by RT-PCR, regardless of symptoms, with onset within 4&#xa0;weeks after the second dose of the initial vaccination series until the second dose of the crossover series. Secondary outcomes were vaccine efficacy against asymptomatic and minimally symptomatic SARS-CoV-2 infection, durability of vaccine efficacy against SARS-CoV-2 infection, and durability of vaccine efficacy against asymptomatic and minimally symptomatic infections. Outcomes were analysed in the modified intention-to-treat population, which included all participants without previous SARS-CoV-2 infection and was restricted to participants enrolled within 4&#xa0;weeks of the second dose of the primary (primary analysis population) or crossover (post-crossover analysis population) series. This&#xa0;study is registered with ClinicalTrials.gov (NCT04611802). FINDINGS: Between June 1 and Dec 17, 2021, 1196 (53&#xb7;2%) of the 2247&#xa0;adolescent participants recruited in the PREVENT-19 trial enrolled in the SNIFF study. The primary analysis population included 471&#xa0;participants in the immediate NVX-CoV2373 group and 220&#xa0;in the delayed NVX-CoV2373 group. Incidence of SARS-CoV-2 infection was 14&#xb7;9&#xa0;cases per 100 person-years (95% CI 7&#xb7;9-25&#xb7;5) in the immediate group and 54&#xb7;2&#xa0;cases per 100 person-years (33&#xb7;6-82&#xb7;9) in the delayed group; vaccine efficacy was 73&#xb7;5% (95% CI 47&#xb7;1-86&#xb7;7; p=0&#xb7;0002). Incidence of minimally symptomatic or asymptomatic SARS-CoV-2 infection was 10&#xb7;3&#xa0;cases per 100 person-years (95% CI 4&#xb7;7-19&#xb7;6) in the&#xa0;immediate group and 36&#xb7;1&#xa0;cases per 100 person-years (19&#xb7;8-60&#xb7;7) in the delayed group; vaccine efficacy was 72&#xb7;8% (95% CI 37&#xb7;1-88&#xb7;2; p=0&#xb7;0023). After the second crossover dose, incidence of SARS-CoV-2 was 14&#xb7;6&#xa0;cases per 100 person-years (95% CI 8&#xb7;6-23&#xb7;0) in the immediate group (receiving placebo at crossover) and 9&#xb7;1&#xa0;cases per 100&#xa0;person-years (3&#xb7;0-21&#xb7;3) in the delayed group, with a durability ratio of 160&#xb7;3 (95% CI 59&#xb7;5-431&#xb7;6; p=0&#xb7;35). Almost all infections after crossover were minimally symptomatic or asymptomatic, with a durability ratio of 151&#xb7;4&#xa0;(55&#xb7;9-410&#xb7;4; p=0&#xb7;41). INTERPRETATION: Among adolescents participating in the PREVENT-19 trial during the delta (B.1.617.2) variant wave of the COVID-19 pandemic, the NVX-CoV2373 vaccine was highly efficacious against SARS-CoV-2 infection regardless of symptoms, indicating its potential to reduce the reservoir of infections that contribute to community transmission. FUNDING: US Department of Health and Human Services, Administration for Strategic Preparedness and Response, Biomedical Advanced Research and Development Authority, National Institute of Allergy and Infectious Diseases, and National Institutes of Health.

Adolescent

Spatial-temporal and phylogenetic analyses of epidemiologic data to help understand the modes of transmission of endemic typhoid fever in Samoa.

Salmonella enterica serovar Typhi (S. Typhi) is either widely distributed or proximally transmitted via fecally-contaminated food or water to cause typhoid fever. In Samoa, where endemic typhoid fever has persisted over decades despite water quality and sanitation improvements, the local patterns of S. Typhi circulation remain unclear. From April 2018-June 2020, epidemiologic data and GPS coordinates were collected during household investigations of 260 acute cases of typhoid fever, and 27 asymptomatic shedders of S. Typhi were detected among household contacts. Spatial and temporal distributions of cases were examined using Average Nearest Neighbor and space-time hotspot analyses. In rural regions, infections occurred in sporadic, focal clusters contrasting with persistent, less clustered cases in the Apia Urban Area. Restrictions to population movement during nationwide lockdowns in 2019-2020 were associated with marked reductions of cases. Phylogenetic analyses of isolates with whole genome sequences (n = 186) revealed one dominant genotype 3.5.4 (n = 181/186) that contains three Samoa-exclusive sub-lineages: 3.5.4.1, 3.5.4.2, and 3.5.4.3. Variables of patient sex, age, and geographic region were examined by phylogenetic groupings, and significant differences (p<0.05) associated genetically-similar isolates in urban areas with working ages (20-49 year olds), and in rural areas with age groups typically at home (<5, 50+). Isolates from asymptomatic shedders were among all three sub-lineages. Whole genome sequencing provided evidence of bacterial genetic similarity, which corroborated 10/12 putative epidemiologic linkages among cases and asymptomatic shedders, as well as 3/3 repeat positives (presumed relapses), with a median of one single nucleotide polymorphism difference. These findings highlight various patterns of typhoid transmission in Samoa that differ between urban and rural regions as well as genomic subtypes. Asymptomatic shedders, detectable only through household investigations, are likely an important reservoir and mobile agent of infection. This study advances a "Samoan S. Typhi framework" that supports current and future typhoid surveillance and control efforts in Samoa.

Humans

Automated Deep Learning-Based Detection of Early Atherosclerotic Plaques in Carotid Ultrasound Imaging.

BACKGROUND: Carotid plaque presence is associated with cardiovascular risk, even among asymptomatic individuals. While deep learning has shown promise for carotid plaque phenotyping in patients with advanced atherosclerosis, its application in population-based settings of asymptomatic individuals remains unexplored. METHODS: We developed a YOLOv8-based model for plaque detection using carotid ultrasound images from 19,499 participants of the population-based UK Biobank (UKB) and fine-tuned it for external validation in the BiDirect study (N = 2,105). Cox regression was used to estimate the impact of plaque presence and count on major cardiovascular events. To explore the genetic architecture of carotid atherosclerosis, we conducted a genome-wide association study (GWAS) meta-analysis of the UKB and CHARGE cohorts. Mendelian randomization (MR) assessed the effect of genetic predisposition to vascular risk factors on carotid atherosclerosis. RESULTS: Our model demonstrated high performance with accuracy, sensitivity, and specificity exceeding 85%, enabling identification of carotid plaques in 45% of the UKB population (aged 47-83 years). In the external BiDirect cohort, a fine-tuned model achieved 86% accuracy, 78% sensitivity, and 90% specificity. Plaque presence and count were associated with risk of major adverse cardiovascular events (MACE) over a follow-up of up to seven years, improving risk reclassification beyond the Pooled Cohort Equations. A GWAS meta-analysis of carotid plaques uncovered two novel genomic loci, with downstream analyses implicating targets of investigational drugs in advanced clinical development. Observational and MR analyses showed associations between smoking, LDL cholesterol, hypertension, and odds of carotid atherosclerosis. CONCLUSIONS: Our model offers a scalable solution for early carotid plaque detection, potentially enabling automated screening in asymptomatic individuals and improving plaque phenotyping in population-based cohorts. This approach could advance large-scale atherosclerosis research.

atherosclerosis