Background: Lung-transplant (LT) recipients are at high risk for COVID-19 due to immunosuppression and respiratory tropism of SARS-CoV-2. The information on the effect of COVID-19 mRNA vaccines to elicit immunogenic responses after a two-dose (2D) regimen in LT recipients is sparse. Thus, we assessed the effect of Pfizer-BioNTech and Moderna mRNA vaccines’ 2D regimen on anti-spike responses in immunocompromised LT recipients. Methods: We utilized serum samples from LT recipients vaccinated for SARS-CoV-2 with 2D of either the Pfizer-BioNTech or Moderna vaccines and 2D-vaccinated naïve (non-transplanted and non-exposed to COVID-19) group. Antibody responses were assessed using the FDA-approved SARS-CoV-2 anti-nucleocapsid protein IgG assay (IgG_NC), the SARS-CoV-2 anti-spike protein IgM assay (IgM_SP), and the SARS-CoV-2 anti-spike protein IgG II assay (IgG_SP). CD4+ T-cell activity was assessed as a marker of immune competence using the ImmuKnow^® assay. Results: About 25% (18/73) of SARS-CoV-2 uninfected-LT patients generated a positive spike-IgG response following 2D of vaccines, with 36% (9/25) in the Moderna cohort and only 19% (9/48) in the Pfizer cohort. 2D in LT patients elicited a significantly lesser median IgG_SP response (1.7 AU/mL, 95% CI: 0.6–7.5 AU/mL) compared to non-transplanted, uninfected naïve subjects (14,209 AU/mL, 95% CI: 11,261–18,836 AU/mL; p < 0.0001). In LT patients, the Moderna-evoked seropositivity trend was higher than Pfizer. Conclusion: 2D COVID-19 vaccination elicits a dampened serological response in LT patients. Whether assessing other arms of host immunity combined with a higher vaccine dose can better capture and elicit improved immunogenicity in this immunocompromised population warrants investigation.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has presented significant challenges for laboratories including supply chain limitations with restricted access to reagents and sample collection materials (i.e. swabs, viral transport media (VTM)) for patients testing. Therefore, saliva has been evaluated as an alternative specimen for COVID-19 diagnosis. comparable performance between dry nasal swabs (NS) and nasopharyngeal swabs (NPS) collected in VTM has been observed with the ID NOW for SARS-CoV-2; the majority of false-negative results occur with higher cycle number (CN) or cycle threshold (Ct) values suggesting low viral load in these specimens. We performed clinical validation of saliva specimens on the ID NOW molecular platform to detect SARS-CoV-2. Saliva was compared to nasopharyngeal swabs tested on the ID NOW and the Cepheid molecular assay. We also performed stability studies of saliva samples over 5 days. A total of 96 saliva samples and 64 paired NPS were analyzed. We observed 78% (18/23) positive percent agreement (PPA) and 100% (44/44) negative percent agreement (NPA) between matched saliva and nasopharyngeal specimens performed on ID NOW. We found 83% (19/23) PPA and 100% NPA (25/25) between saliva run on the ID NOW and Cepheid assay. Six saliva specimens positive for SARS-CoV-2 were continuously positive for five days when stored at room temperature. Therefore, we propose further investigation of saliva as an alternative sample type for testing symptomatic patients with ID NOW as a promising method to address COVID-19 testing.

Background: The persisting Coronavirus disease 2019 (COVID-19) pandemic and limited vaccine supply has led to a shift in global health priorities to expand vaccine coverage. Relying on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) molecular testing alone cannot reveal the infection proportion, which could play a critical role in vaccination prioritization. We evaluated the utility of a combination orthogonal serological testing (COST) algorithm alongside RT-PCR to quantify prevalence with the aim of identifying candidate patient clusters to receive single and/or delayed vaccination. Methods: We utilized 108,505 patients with suspected COVID-19 in a retrospective analysis of SARS-CoV-2 RT-PCR vs. IgG-nucleocapsid (IgG_NC) antibody testing coverage in routine practice for the estimation of prevalence. Prospectively, an independent cohort of 21,388 subjects was simultaneously tested by SARS-CoV-2 RT-PCR and IgG_NC to determine the prevalence. We used 614 prospective study subjects to assess the utility of COST (IgG_NC, IgM-spike (IgM_SP), and IgG-spike (IgG_SP)) in establishing the infection proportion to identify a single-dose vaccination cohort. Results: Retrospectively, we observed a 6.3% (6871/108,505) positivity for SARS-CoV-2 RT-PCR, and only 2.3% (2533/108,505) of cases had paired IgG_NC serology performed. Prospectively, IgG_NC serology identified twice the number of COVID-positive cases in relation to RT-PCR alone. COST further increased the number of detected positive cases: IgG_NC+ or IgM_SP+ (18.0%); IgG_NC+ or IgG_SP+ (23.5%); IgM_SP+ or IgG_SP+ (23.8%); and IgG_NC+ or IgM_SP+ or IgG_SP+ (141/584 = 24.1%). Conclusion: COST may be an effective tool for the evaluation of infection proportion and thus could define a cohort for a single dose and/or delayed vaccination.

Concomitant infection of multiple SARS-CoV-2 variants has become an increasing concern, as this scenario increases the likelihood of recombinant variants. Detecting co-infection of SARS-CoV-2 variants is difficult to detect by whole genome sequencing approaches, but genotyping methods facilitate detection. We describe 2 cases of Delta/Omicron and 2 cases of Omicron sublineage BA.1/ BA.2 co-infection as detected by a multiplex genotyping fragment analysis method. Findings were confirmed by whole genome sequencing. Review of the patient characteristics revealed co-morbidities and conditions which weaken the immune system and may make them more susceptible to harboring SARS-CoV-2 variant co-infections.

Background: Local antibiograms are a highly useful tool to guide empiric antibiotic therapy for a variety of infections. Objectives: This study compares nitrofurantoin (NF) susceptibility in outpatient urine isolates using antibiogram data from two United States academic medical centers. Methods: In this brief report, we compare antibiograms of urinary isolates from two distinct academic institutions—the University of Texas Southwestern (UTSW) in Dallas, Texas, and the University of Kansas Medical Center (KU) in Kansas City, Kansas—focusing on the most common uropathogens susceptible to NF to evaluate whether NF remains an appropriate first-line agent for uncomplicated cystitis. Results: For the 2022 antibiogram, KU tested 5,524 urinary isolates and UTSW tested 2,530 urinary isolates. The susceptibility data were consistent across the two institutions, suggesting that NF can continue to be considered a first-line therapy for uncomplicated urinary tract infections in women. Conclusion: This report highlights the importance of clinicians consulting their local antibiograms to inform empiric antibiotic therapy.