Severe Acute Respiratory Syndrome Coronavirus 2 Vasculopathy in a Syrian Golden Hamster Model.

Clinical evidence of vascular dysfunction and hypercoagulability as well as pulmonary vascular damage and microthrombosis are frequently reported in severe cases of human coronavirus disease 2019 (COVID-19). Syrian golden hamsters recapitulate histopathologic pulmonary vascular lesions reported in patients with COVID-19. Herein, special staining techniques and transmission electron microscopy further define vascular pathologies in a Syrian golden hamster model of human COVID-19. The results show that regions of active pulmonary inflammation in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are characterized by ultrastructural evidence of endothelial damage with platelet marginalization and both perivascular and subendothelial macrophage infiltration. SARS-CoV-2 antigen/RNA was not detectable within affected blood vessels. Taken together, these findings suggest that the prominent microscopic vascular lesions in SARS-CoV-2-inoculated hamsters likely occur due to endothelial damage followed by platelet and macrophage infiltration.

SARS-CoV-2 vasculopathy in a Syrian golden hamster model

Clinical evidence of vascular dysfunction and hypercoagulability as well as pulmonary vascular damage and microthrombosis are frequently reported in severe cases of human COVID-19 disease. Syrian golden hamsters recapitulate histopathologic pulmonary vascular lesions reported in COVID-19 patients. Here, special staining techniques and transmission electron microscopy further define vascular pathologies in a Syrian golden hamster model of human COVID-19 disease. The results show that regions of active pulmonary inflammation in SARS-CoV-2 infection are characterized by ultrastructural evidence of endothelial damage with platelet marginalization and both perivascular and subendothelial macrophage infiltration. SARS-CoV-2 antigen/RNA was not detectable within affected blood vessels. Taken together, these findings suggest that the prominent microscopic vascular lesions in SARS-CoV-2 inoculated hamsters are likely due to endothelial damage followed by platelet and macrophage infiltration.

Neonatal Use of Acute Care Services During the COVID-19 Pandemic.

OBJECTIVE: To describe changes in neonatal use of acute care services during the coronavirus disease 2019 (COVID-19) pandemic. We hypothesized neonatal visits would decrease and the degree of decline would vary by condition. METHODS: We conducted a retrospective cohort study of neonatal visits to the urgent cares, emergency departments, inpatient units, and intensive care units at a free-standing pediatric healthcare system during the COVID-19 pandemic and a comparator period. We included visits of infants presenting for acute care within the first 30 days of life. Transfers from a referring nursery, inpatient unit, or ICU were excluded. Data collected included demographics, patient characteristics, and visit characteristics. Descriptive statistics and χ2 tests were used for analyses and to determine statistically significant differences. RESULTS: We identified 4439 neonatal acute care visits, of which 2677 occurred in the prepandemic period and 1762 in the COVID-19 pandemic period, representing a 34.2% decline. Urgent cares and emergency departments experienced the greatest decline in visits for infectious conditions (49%) and the proportion of these visits also significantly decreased. Similarly, the largest clinically significant declines in hospitalizations were for infectious and respiratory diagnoses (48% and 52%, respectively) and the proportions of these hospitalizations also significantly decreased. Despite a small decline in hospitalizations for jaundice, the proportion of jaundice hospitalizations significantly increased by 5.7% (P = .02). CONCLUSIONS: The COVID-19 pandemic was associated with a significant reduction in neonatal visits across a spectrum of acute care settings. The impact on use varied by diagnosis with the most notable decline in visits for infectious conditions.