Secondary Complement Deficiency Impairs Anti-Microbial Immunity to Klebsiella pneumoniae and Staphylococcus aureus During Severe Acute COVID-19.

A high incidence of secondary Klebsiella pneumoniae and Staphylococcus aureus infection were observed in patients with severe COVID-19. The cause of this predisposition to infection is unclear. Our data demonstrate consumption of complement in acute COVID-19 patients reflected by low levels of C3, C4, and loss of haemolytic activity. Given that the elimination of Gram-negative bacteria depends in part on complement-mediated lysis, we hypothesised that secondary hypocomplementaemia is rendering the antibody-dependent classical pathway activation inactive and compromises serum bactericidal activity (SBA). 217 patients with severe COVID-19 were studied. 142 patients suffered secondary bacterial infections. Klebsiella species were the most common Gram-negative organism, found in 58 patients, while S. aureus was the dominant Gram-positive organism found in 22 patients. Hypocomplementaemia was observed in patients with acute severe COVID-19 but not in convalescent survivors three months after discharge. Sera from patients with acute COVID-19 were unable to opsonise either K. pneumoniae or S. aureus and had impaired complement-mediated killing of Klebsiella. We conclude that hyperactivation of complement during acute COVID-19 leads to secondary hypocomplementaemia and predisposes to opportunistic infections.

Ensuring Sustainability of Continuous Kidney Replacement Therapy in the Face of Extraordinary Demand: Lessons From the COVID-19 Pandemic.

With the exponential surge in patients with coronavirus disease 2019 (COVID-19) worldwide, the resources needed to provide continuous kidney replacement therapy (CKRT) for patients with acute kidney injury or kidney failure may be threatened. This article summarizes subsisting strategies that can be implemented immediately. Pre-emptive weekly multicenter projections of CKRT demand based on evolving COVID-19 epidemiology and routine workload should be made. Corresponding consumables should be quantified and acquired, with diversification of sources from multiple vendors. Supply procurement should be stepped up accordingly so that a several-week stock is amassed, with administrative oversight to prevent disproportionate hoarding by institutions. Consumption of CKRT resources can be made more efficient by optimizing circuit anticoagulation to preserve filters, extending use of each vascular access, lowering blood flows to reduce citrate consumption, moderating the CKRT intensity to conserve fluids, or running accelerated KRT at higher clearance to treat more patients per machine. If logistically feasible, earlier transition to intermittent hemodialysis with online-generated dialysate, or urgent peritoneal dialysis in selected patients, may help reduce CKRT dependency. These measures, coupled to multicenter collaboration and a corresponding increase in trained medical and nursing staffing levels, may avoid downstream rationing of care and save lives during the peak of the pandemic.

YouTube as source of information on 2019 novel coronavirus outbreak: a cross sectional study of English and Mandarin content.

BACKGROUND: The current 2019 novel coronavirus outbreak is rapidly evolving. YouTube has been recognized as a popular source of information in previous disease outbreaks. We analyzed the content on YouTube about n-CoV in English and Mandarin languages. METHODS: YouTube was searched using the terms '2019 novel coronavirus', 'Wuhan virus' and '' (Mandarin for Wuhan virus) on 1st and 2nd February 2020. First 50 videos in each group were analyzed. Videos in other languages, duplicate videos, those without an audio and duration >15 min were excluded .72 videos in English and 42 in Mandarin were reviewed. 2 reviewers classified the videos as useful, misleading or news based on pre specified criterion. Inter-observer agreement was evaluated with kappa coefficient. Modified DISCERN index for reliability and medical information and content index (MICI) score were used for content analysis. RESULTS: These videos attracted cumulative 21,288,856 views. 67% of English and 50% Mandarin videos had useful information. The viewership of misleading Mandarin videos was higher than the useful ones. WHO accounted for only 4% of useful videos. Mean DISCERN score for reliability was 3.12/5 and 3.25/5 for English and Mandarin videos respectively. Mean cumulative MICI score of useful videos was low (6.71/25 for English and 6.28/25 for Mandarin). CONCLUSIONS: YouTube viewership during 2019 n-CoV outbreak is higher than previous outbreaks. The medical content of videos is suboptimal International health agencies are underrepresented. Given its popularity, YouTube should be considered as important platform for information dissemination.