The coronavirus pandemic has created worldwide shortages of N95 respirators. We analyzed 4 decontamination methods for effectiveness in deactivating severe acute respiratory syndrome coronavirus 2 virus and effect on respirator function. Our results indicate that N95 respirators can be decontaminated and reused, but the integrity of respirator fit and seal must be maintained.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA is frequently detected in the feces of infected individuals. While infectious SARS-CoV-2 has not previously been identified in wastewater, infectious SARS-CoV-2 has been isolated from the feces of at least one patient, raising concerns about the presence of infectious SARS-CoV-2 in wastewater. The fate and inactivation characteristics of SARS-CoV-2 in water and wastewater are unknown, with current inactivation estimates based on surrogate models. In this study, the persistence of SARS-CoV-2 infectivity and RNA signal was determined in water and wastewater. The times for 90% reduction ( T 90 ) of viable SARS-CoV-2 in wastewater and tap water at room temperature were 1.5 and 1.7 days, respectively. In high-starting titer (10 5 TCID 50 mL –1 ) experiments, infectious virus persisted for the entire 7-day sampling time course. In wastewater at 50 and 70 °C, the observed T 90 values for infectious SARS-CoV-2 were decreased to 15 and 2 min, respectively. SARS-CoV-2 RNA was found to be significantly more persistent than infectious SARS-CoV-2, indicating that the environmental detection of RNA alone does not substantiate risk of infection.

SARS-CoV-2 emerged in late 2019 and resulted in the ongoing COVID-19 pandemic. Several animal models have been rapidly developed that recapitulate the asymptomatic to moderate disease spectrum. Now, there is a direct need for additional small animal models to study the pathogenesis of severe COVID-19 and for fast-tracked medical countermeasure development. Here, we show that transgenic mice expressing the human SARS-CoV-2 receptor (angiotensin-converting enzyme 2 [hACE2]) under a cytokeratin 18 promoter (K18) are susceptible to SARS-CoV-2 and that infection resulted in a dose-dependent lethal disease course. After inoculation with either 104 TCID50 or 105 TCID50, the SARS-CoV-2 infection resulted in rapid weight loss in both groups and uniform lethality in the 105 TCID50 group. High levels of viral RNA shedding were observed from the upper and lower respiratory tract and intermittent shedding was observed from the intestinal tract. Inoculation with SARS-CoV-2 resulted in upper and lower respiratory tract infection with high infectious virus titers in nasal turbinates, trachea and lungs. The observed interstitial pneumonia and pulmonary pathology, with SARS-CoV-2 replication evident in pneumocytes, were similar to that reported in severe cases of COVID-19. SARS-CoV-2 infection resulted in macrophage and lymphocyte infiltration in the lungs and upregulation of Th1 and proinflammatory cytokines/chemokines. Extrapulmonary replication of SARS-CoV-2 was observed in the cerebral cortex and hippocampus of several animals at 7 DPI but not at 3 DPI. The rapid inflammatory response and observed pathology bears resemblance to COVID-19. Additionally, we demonstrate that a mild disease course can be simulated by low dose infection with 102 TCID50 SARS-CoV-2, resulting in minimal clinical manifestation and near uniform survival. Taken together, these data support future application of this model to studies of pathogenesis and medical countermeasure development.

Middle East Respiratory Syndrome coronavirus (MERS-CoV) causes a highly lethal pulmonary infection with ∼35% mortality. The potential for a future pandemic originating from animal reservoirs or healthcare-associated events is a major public health concern. There are no vaccines or therapeutic agents currently available for MERS-CoV. Using a probe-based single B cell-cloning strategy, we have identified and characterized multiple neutralizing mAbs specifically binding to the receptor binding domain (RBD) or S1 (non-RBD) regions from a convalescent MERS-CoV-infected patient and from immunized rhesus macaques. RBD-specific mAbs tended to have greater neutralizing potency than non-RBD S1-specific mAbs. Six RBD-specific and five S1-specific mAbs could be sorted into four RBD and three non-RBD distinct binding patterns, based on competition assays, mapping neutralization escape variants, and structural analysis. We determined co-crystal structures for two mAbs targeting RBD from different angles and show they can only bind RBD in the "out" position. We then showed that selected RBD-specific, non-RBD S1, and S2-specific mAbs given prophylactically prevented MERS-CoV replication in lungs and protected mice from lethal challenge. Importantly, combining RBD- and non-RBD mAbs delayed the emergence of escape mutations in a cell-based virus-escape assay. These studies identify mAbs targeting different antigenic sites on S that will be useful for defining mechanisms of MERS-CoV neutralization, and for developing more effective interventions to prevent or treat MERS-CoV infections. MERS-CoV causes a highly lethal respiratory infection for which no vaccines or antiviral therapeutic options are currently available. Based on continuing exposure from established reservoirs in dromedary camels and bats, transmission of MERS-CoV into humans and future outbreaks are expected. Using structurally-defined probes for the MERS-CoV Spike (S) glycoprotein, the target for neutralizing antibodies, single B cells were sorted from a convalescent human and immunized non-human primates (NHPs). mAbs produced from paired immunoglobulin gene sequences were mapped to multiple epitopes within and outside the receptor-binding domain (RBD) and protected against lethal MERS infection in a murine model following passive immunization. Importantly, combining mAbs targeting distinct epitopes prevented viral neutralization escape from RBD-directed mAbs. These data suggest that antibody responses to multiple domains on CoV Spike may improve immunity and will guide future vaccine and therapeutic development efforts.