As severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) infections continue, there is a substantial need for cost‐effective and large‐scale testing that utilizes specimens that can be readily collected from both symptomatic and asymptomatic individuals in various community settings. Although multiple diagnostic methods utilize nasopharyngeal specimens, saliva specimens represent an attractive alternative as they can rapidly and safely be collected from different populations. While saliva has been described as an acceptable clinical matrix for the detection of SARS‐CoV‐2, evaluations of analytic performance across platforms for this specimen type are limited. Here, we used a novel sensitive RT‐PCR/MALDI‐TOF mass spectrometry‐based assay (Agena MassARRAY®) to detect SARS‐CoV‐2 in saliva specimens. The platform demonstrated high diagnostic sensitivity and specificity when compared to matched patient upper respiratory specimens. We also evaluated the analytical sensitivity of the platform and determined the limit of detection of the assay to be 1562.5 copies/ml. Furthermore, across the five individual target components of this assay, there was a range in analytic sensitivities for each target with the N2 target being the most sensitive. Overall, this system also demonstrated comparable performance when compared to the detection of SARS‐CoV‐2 RNA in saliva by the cobas® 6800/8800 SARS‐CoV‐2 real‐time RT‐PCR Test (Roche). Together, we demonstrate that saliva represents an appropriate matrix for SARS‐CoV‐2 detection on the novel Agena system as well as on a conventional real‐time RT‐PCR assay. We conclude that the MassARRAY® system is a sensitive and reliable platform for SARS‐CoV‐2 detection in saliva, offering scalable throughput in a large variety of clinical laboratory settings.

Persistent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have been reported in immune-compromised individuals and people undergoing immune-modulatory treatments. Although intrahost evolution has been documented, direct evidence of subsequent transmission and continued stepwise adaptation is lacking. Here we describe sequential persistent SARS-CoV-2 infections in three individuals that led to the emergence, forward transmission, and continued evolution of a new Omicron sublineage, BA.1.23, over an eight-month period. The initially transmitted BA.1.23 variant encoded seven additional amino acid substitutions within the spike protein (E96D, R346T, L455W, K458M, A484V, H681R, A688V), and displayed substantial resistance to neutralization by sera from boosted and/or Omicron BA.1-infected study participants. Subsequent continued BA.1.23 replication resulted in additional substitutions in the spike protein (S254F, N448S, F456L, M458K, F981L, S982L) as well as in five other virus proteins. Our findings demonstrate not only that the Omicron BA.1 lineage can diverge further from its already exceptionally mutated genome but also that patients with persistent infections can transmit these viral variants. Thus, there is, an urgent need to implement strategies to prevent prolonged SARS-CoV-2 replication and to limit the spread of newly emerging, neutralization-resistant variants in vulnerable patients.

Monkeypox virus (MPXV) is a zoonotic orthopoxvirus within the Poxviridae family. MPXV is endemic to Central and West Africa. However, the world is currently witnessing an international outbreak with no clear epidemiological links to travel or animal exposure and with ever‐increasing numbers of reported cases worldwide. Here, we evaluated and validated a new, sensitive, and specific real‐time PCR‐assay for MPXV diagnosis in humans and compare the performance of this novel assay against a Food & Drug Administration‐cleared pan‐Orthopox RT‐PCR assay. We determined specificity, sensitivity, and analytic performance of the PKamp™ Monkeypox Virus RT‐PCR assay targeting the viral F3L‐gene. In addition, we further evaluated MPXV‐PCR‐positive specimens by viral culture, electron microscopy, and viral inactivation assays. The limit of detection was established at 7.2 genome copies/reaction, and MPXV was successfully identified in 20 clinical specimens with 100% correlation against the reference method with 100% sensitivity and specificity. Our results demonstrated the validity of this rapid, robust, and reliable RT‐PCR assay for specific and accurate diagnosis of MPXV infection in human specimens collected both as dry swabs and in viral transport media. This assay has been approved by NYS Department of Health for clinical use.

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Persistent SARS-CoV-2 infections have been reported in immune-compromised individuals and people undergoing immune-modulatory treatments. It has been speculated that the emergence of antigenically diverse SARS-CoV-2 variants such as the Omicron variant may be the result of intra-host viral evolution driven by suboptimal immune responses, which must be followed by forward transmission. However, while intrahost evolution has been documented, to our knowledge no direct evidence of subsequent forward transmission is available to date. Here we describe the emergence of an Omicron BA.1 sub-lineage with 8 additional amino acid substitutions within the spike (E96D, L167T, R346T, L455W, K458M, A484V, H681R, A688V) in an immune-compromised host along with evidence of 5 forward transmission cases. Our findings show that the Omicron BA.1 lineage can further diverge from its exceptionally mutated genome during prolonged SARS-CoV-2 infection; highlighting an urgent need to employ therapeutic strategies to limit duration of infection and spread in vulnerable patients.