Severe acute respiratory coronavirus virus 2 (SARS-CoV-2) nosocomial transmission dynamics, a retrospective cohort study of two healthcare-associated coronavirus disease 2019 (COVID-19) clusters in a district hospital in England during March and April 2020.

OBJECTIVE: To understand the transmission dynamics of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in a hospital outbreak to inform infection control actions. DESIGN: Retrospective cohort study. SETTING: General medical and elderly inpatient wards in a hospital in England. METHODS: Coronavirus disease 2019 (COVID-19) patients were classified as community or healthcare associated by time from admission to onset or positivity using European Centre for Disease Prevention and Control definitions. COVID-19 symptoms were classified as asymptomatic, nonrespiratory, or respiratory. Infectiousness was calculated from 2 days prior to 14 days after symptom onset or positive test. Cases were defined as healthcare-associated COVID-19 when infection was acquired from the wards under investigation. COVID-19 exposures were calculated based on symptoms and bed proximity to an infectious patient. Risk ratios and adjusted odds ratios (aORs) were calculated from univariable and multivariable logistic regression. RESULTS: Of 153 patients, 65 were COVID-19 patients and 45 of these were healthcare-associated cases. Exposure to a COVID-19 patient with respiratory symptoms was associated with healthcare-associated infection irrespective of proximity (aOR, 3.81; 95% CI, 1.6.3-8.87). Nonrespiratory exposure was only significant within 2.5 m (aOR, 5.21; 95% CI, 1.15-23.48). A small increase in risk ratio was observed for exposure to a respiratory patient for >1 day compared to 1 day from 2.04 (95% CI, 0.99-4.22) to 2.36 (95% CI, 1.44-3.88). CONCLUSIONS: Respiratory exposure anywhere within a 4-bed bay was a risk, whereas nonrespiratory exposure required bed distance ≤2.5 m. Standard infection control measures required beds to be >2 m apart. Our findings suggest that this may be insufficient to stop SARS-CoV-2 transmission. We recommend improving cohorting and further studies into bed distance and transmission factors.

Dexamethasone treatment may mitigate adverse effects of vitamin D deficiency in hospitalized Covid-19 patients.

AIMS: We have previously demonstrated that vitamin D deficiency might be associated with worse outcomes in hospitalized Covid-19 patients. The aim of our study was to explore this relationship with dexamethasone therapy. METHODS: We prospectively studied two cohorts of hospitalized Covid-19 patients between March and April and between September and December 2020 (n = 192). Patients were tested for serum 25-hydroxyvitamin D (25-OH-D) levels during admission. The first cohort not treated with dexamethasone (n = 107) was divided into vitamin D deficient (25-OH-D ≤ 30 nmol/L) (n = 47) and replete subgroups (25-OH-D > 30 nmol/L) (n = 60). The second cohort treated with dexamethasone (n = 85) was similarly divided into deficient (25-OH-D ≤ 30 nmol/L) (n = 27) and replete subgroups (25-OH-D > 30 nmol/L) (n = 58). Primary outcome was in-hospital mortality and secondary outcomes were elevation in markers of cytokine storm and ventilatory requirement. RESULTS: No mortality difference was identified between cohorts and subgroups. The "no dexamethasone" cohort 25-OH-D deplete subgroup recorded significantly higher peak D-Dimer levels (1874 vs. 1233 µgFEU/L) (p = 0.0309), CRP (177 vs. 107.5) (p = 0.0055), and ventilatory support requirement (25.5% vs. 6.67%) (p = 0.007) compared to the replete subgroup. Among the 25-OH-D deplete subgroup higher peak neutrophil counts, peak CRP, peak LDH, peak ferritin, and lower trough lymphocyte counts were observed, without statistical significance. In the "dexamethasone" cohort, there was no apparent association between 25-OH-D deficiency and markers of cytokine storm or ventilatory requirement. CONCLUSION: Vitamin D deficiency is associated with elevated markers of cytokine storm and higher ventilatory requirements in hospitalized Covid-19 patients. Dexamethasone treatment appears to mitigate adverse effects of vitamin D deficiency.

Vitamin D status and outcomes for hospitalised older patients with COVID-19.

PURPOSE: Older adults are more likely to be vitamin D deficient. The aim of the study was to determine whether these patients have worse outcomes with COVID-19. METHODS: We conducted a prospective cohort study between 1 March and 30 April 2020 to assess the importance of vitamin D deficiency in older patients with COVID-19. The cohort consisted of patients aged ≥65 years presenting with symptoms consistent with COVID-19 (n=105). All patients were tested for serum 25-hydroxyvitamin D (25(OH)D) levels during acute illness. Diagnosis of COVID-19 was confirmed via viral reverse transcriptase PCR swab or supporting radiological evidence. COVID-19-positive arm (n=70) was sub-divided into vitamin D-deficient (≤30 nmol/L) (n=39) and -replete groups (n=35). Subgroups were assessed for disease severity using biochemical, radiological and clinical markers. Primary outcome was in-hospital mortality. Secondary outcomes were laboratory features of cytokine storm, thoracic imaging changes and requirement of non-invasive ventilation (NIV). RESULTS: COVID-19-positive arm demonstrated lower median serum 25(OH)D level of 27 nmol/L (IQR=20-47 nmol/L) compared with COVID-19-negative arm, with median level of 52 nmol/L (IQR=31.5-71.5 nmol/L) (p value=0.0008). Among patients with vitamin D deficiency, there was higher peak D-dimer level (1914.00 µgFEU/L vs 1268.00 µgFEU/L) (p=0.034) and higher incidence of NIV support and high dependency unit admission (30.77% vs 9.68%) (p=0.042). No increased mortality was observed between groups. CONCLUSION: Older adults with vitamin D deficiency and COVID-19 may demonstrate worse morbidity outcomes. Vitamin D status may be a useful prognosticator.

Pulmonary embolism in COVID-19: Clinical characteristics and cardiac implications.

BACKGROUND: The thrombogenic potential of Covid-19 is increasingly recognised. We aim to assess the characteristics of COVID-19 patients diagnosed with pulmonary embolism (PE). METHODS: We conducted a single centre, retrospective observational cohort study of COVID-19 patients admitted between 1st March and 30th April 2020 subsequently diagnosed with PE following computed tomography pulmonary angiogram (CTPA). Patient demographics, comorbidities, presenting complaints and inpatient investigations were recorded. RESULTS: We identified 15 COVID-19 patients diagnosed with PE (median age = 58 years [IQR = 23], 87% male). 2 died (13%), both male patients >70 years. Most common symptoms were dyspnoea (N = 10, 67%) and fever (N = 7, 47%). 12 (80%) reported 7 days or more of non-resolving symptoms prior to admission. 7 (47%) required continuous positive airway pressure (CPAP), 2 (13%) of which were subsequently intubated. All patients had significantly raised D-dimer levels, lactate dehydrogenase (LDH), C-reactive protein (CRP), ferritin and prothrombin times. The distribution of PEs correlated with the pattern of consolidation observed on CTPA in 9 (60%) patients; the majority being peripheral or subsegmental (N = 14, 93%) and only 1 central PE. 10 (67%) had an abnormal resting electrocardiogram (ECG), the commonest finding being sinus tachycardia. 6 (40%) who underwent transthoracic echocardiography (TTE) had structurally and functionally normal right hearts. CONCLUSION: Our study suggests that patients who demonstrate acute deterioration, a protracted course of illness with non-resolving symptoms, worsening dyspnoea, persistent oxygen requirements or significantly raised D-dimer levels should be investigated for PE, particularly in the context of COVID-19 infection. TTE and to a lesser degree the ECG are unreliable predictors of PE within this context.