Nine isolates of Canine parvovirus (CPV) were obtained from Vietnamese dogs and cats. One canine isolate showed a unique antigenic property which indicates a novel antigenic variant of CPV-2b when examined with hemagglutination inhibition tests using our monoclonal antibodies, 21C3 and 19D7, which were recently developed. This isolate had an amino acid substitution of residue 426, Asp to Glu, and the same substitution has recently been found in CPV from Italian dogs. This study first showed that such substitution caused an antigenic difference demonstrable by monoclonal antibodies and that a similar evolution may have occurred in CPV in Vietnam.

IMPORTANCE Former US football athletes are at increased risk of cardiovascular (CV) morbidity and mortality compared with the general population and other professional athletes. However, responsible maladaptive CV phenotypes have not been fully characterized.OBJECTIVE To address the emergence and progression of multiple independent factors associated with CV risk across serial years of collegiate US football participation. DESIGN, SETTING, AND PARTICIPANTS Collegiate US football athletes from 2 National Collegiate Athletic Association Division I programs were recruited as freshmen between June 2014 and June 2017 and analyzed at multiple points throughout 3 complete years of collegiate US football participation (until January 2019). Excluded athletes were those who did not complete any season of US football training because of injury, illness, or leaving the team. Factors associated with CV risk assessed clinically, by transthoracic echocardiography, and by vascular applanation tonometry were recorded. EXPOSURES The exposure of interest was seasonal US football exposure, including training, competition, and the training environment.MAIN OUTCOMES AND MEASURES Primary outcome measures were left ventricular mass index and geometry (cardiac structure), early diastolic myocardial relaxation velocity (E′; diastolic function), and pulse-wave velocity (arterial stiffness). RESULTS Of 186 individuals recruited as freshmen, 126 athletes were included in analyzed data. Collegiate US football athletes (62 white individuals [49%]; 63 black individuals [50%]; 77 nonlinemen [61%]; 49 linemen [39%]; 126 male individuals [100%]) weighed a mean (SD) of 101.1 (21.0) kg, with a mean systolic blood pressure of 129.1 (11.6) mm Hg at baseline of the freshman season. Adjusting for race, height, and player position, there were significant increases in weight (mean [SE] Δ, 4.

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The BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) vaccines generate potent neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the global emergence of SARS-CoV-2 variants with mutations in the spike protein, the principal antigenic target of these vaccines, has raised concerns over the neutralizing activity of vaccine-induced antibody responses. The Omicron variant, which emerged in November 2021, consists of over 30 mutations within the spike protein. Here, we used an authentic live virus neutralization assay to examine the neutralizing activity of the SARS-CoV-2 Omicron variant against mRNA vaccine-induced antibody responses. Following the 2nd dose, we observed a 30-fold reduction in neutralizing activity against the omicron variant. Through six months after the 2nd dose, none of the sera from naive vaccinated subjects showed neutralizing activity against the Omicron variant. In contrast, recovered vaccinated individuals showed a 22-fold reduction with more than half of the subjects retaining neutralizing antibody responses. Following a booster shot (3rd dose), we observed a 14-fold reduction in neutralizing activity against the omicron variant and over 90% of boosted subjects showed neutralizing activity against the omicron variant. These findings show that a 3rd dose is required to provide robust neutralizing antibody responses against the Omicron variant.

IMPORTANCEDespite the expansion of SARS-CoV-2 testing, available tests have not received Emergency Use Authorization for performance with self-collected anterior nares (nasal) swabs from children younger than 14 years because the effect of pediatric self-swabbing on SARS-CoV-2 test sensitivity is unknown.OBJECTIVE To characterize the ability of school-aged children to self-collect nasal swabs for SARS-CoV-2 testing compared with collection by health care workers.DESIGN, SETTING, AND PARTICIPANTS Cross-sectional study of 197 symptomatic children and adolescents aged 4 to 14 years old. Individuals were recruited based on results of testing in the Children's Healthcare of Atlanta system from July to August 2021.EXPOSURES Children and adolescents were given instructional material consisting of a short instructional video and a handout with written and visual steps for self-swab collection. Participants first provided a self-collected nasal swab. Health care workers then collected a second specimen. MAIN OUTCOMES AND MEASURESThe primary outcome was SARS-CoV-2 detection and relative quantitation by cycle threshold (Ct) in self-vs health care worker-collected nasal swabs when tested with a real-time reverse transcriptase-polymerase chain reaction test with Emergency Use Authorization. RESULTS Among the study participants, 108 of 194 (55.7%) were male and the median age was 9 years (IQR,(6)(7)(8)(9)(10)(11). Of the 196 participants, 87 (44.4%) tested positive for SARS-CoV-2 and 105 (53.6%) tested negative by both self-and health care worker-collected swabs. Two children tested positive by self-or health care worker-collected swab alone; 1 child had an invalid health care worker swab. Compared with health care worker-collected swabs, self-collected swabs had 97.8% (95% CI, 94.7%-100.0%) and 98.1% (95% CI, 95.6%-100.0%) positive and negative percent agreement, respectively, and SARS-CoV-2 Ct values did not differ significantly between groups (mean [SD] Ct, self-swab: 26.7 [5.4] vs health care worker swab: 26.3 [6.0]; P = .65). CONCLUSIONS AND RELEVANCEAfter hearing and seeing simple instructional materials, children and adolescents aged 4 to 14 years self-collected nasal swabs that closely agreed on SARS-CoV-2 detection with swabs collected by health care workers.

SARS-CoV-2 variant detection relies on resource-intensive whole-genome sequencing methods. We sought to develop a scalable protocol for variant detection and surveillance in Paraguay, pairing rRT-PCR for spike mutations with Nanopore sequencing. A total of 201 acute-phase nasopharyngeal samples were included. Samples were positive for the SARS-CoV-2 N2 target and tested with the Spike SNP assay to detect mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). Spike SNP calls were confirmed using amplicon (Sanger) sequencing and whole-genome (Nanopore) sequencing on a subset of samples with confirmed variant lineages. Samples had a mean N2 Ct of 20.8 (SD 5.6); 198/201 samples (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%), which was consistent with the P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%), and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). The results were confirmed using Sanger sequencing in 181/181 samples, and variant calls were consistent with Nanopore sequencing in 29/29 samples. The Spike SNP assay could improve population-level surveillance for mutations associated with SARS-CoV-2 variants and inform the judicious use of sequencing resources.

Our case report describes the rapid detection of the SARS-CoV-2 omicron variant using a combination of targeted spike SNP PCR and viral genome sequencing. This case occurred in a fully vaccinated and boosted returning traveler with mild symptoms who was identified through community surveillance rather than presentation for clinical care.

BackgroundSARS-CoV-2 mutations conferring escape from neutralizing antibodies can arise in immunocompromised patients with prolonged infection, but the conditions that facilitate immune escape are still not fully understood.MethodsWe characterized endogenous immune responses, within-host SARS-CoV-2 evolution, and autologous neutralization of the viral variants that arose in five immunocompromised patients with prolonged infection and B cell deficiencies.ResultsIn two patients treated with the monoclonal antibody bamlanivimab, viral resistance to autologous serum arose early and persisted for several months, accompanied by ongoing evolution in the spike protein. These patients exhibited deficiencies in both T and B cell arms, and one patient succumbed to disease. In contrast, we did not observe spike mutations in immunologically important regions in patients who did not receive exogenous antibodies or who received convalescent plasma and had intact T cell responses to SARS-CoV-2.ConclusionsOur results underscore the potential importance of multiple factors – the absence of an effective endogenous immune response, persistent virus replication, and selective pressure such as single-agent bamlanivimab – in promoting the emergence of SARS-CoV-2 mutations associated with immune evasion. These findings highlight the need for larger clinical studies in immunocompromised populations to better understand the ramifications of different therapies. Our results also confirm that patients with B cell deficiencies can elicit effector T cells and may suggest an important role for T cells in controlling infection, which is relevant to vaccines and therapeutics.