ABSTRACT
We propose a new modeling framework for evaluating the risk of disease transmission during a pandemic in small‐scale settings driven by stochasticity in the arrival and service processes, that is, congestion‐prone confined‐space service facilities. We propose a novel metric, system‐specific basic reproduction rate, inspired by the "basic reproduction rate” concept from epidemiology, which measures the transmissibility of infectious diseases. We derive our metric for various queueing models of service facilities by leveraging a novel queueing‐theoretic notion: sojourn time overlaps. We showcase how our metric can be used to explore the efficacy of a variety of interventions aimed at curbing the spread of disease inside service facilities. Specifically, we focus on some prevalent interventions employed during the COVID‐19 pandemic: limiting the occupancy of service facilities, protecting high‐risk customers (via prioritization or designated time windows), and increasing the service speed (or limiting patronage duration). We discuss a variety of directions for adapting our transmission model to incorporate some more nuanced features of disease transmission, including heterogeneity in the population immunity level, varying levels of mask usage, and spatial considerations in disease transmission.
ABSTRACT
BACKGROUND: Convalescent plasma therapy is used for the treatment of critically ill patients for newly discovered infectious diseases, such as coronavirus disease 2019 (COVID-19) pneumonia, under the premise of lacking specific treatment drugs and corresponding vaccines. But the best timing application of plasma therapy and whether it is effective by antiviral and antibiotic treatment remain unclear. CASE SUMMARY: We describe a patient with COVID-19, a 100-year-old, high-risk, elderly male who had multiple underlying diseases such as stage 2 hypertension (very high-risk group) and infectious pneumonia accompanied by chronic obstructive pulmonary disease and emphysema. We mainly describe the diagnosis, clinical process, and treatment of the patient, including the processes of two plasma transfusion treatments. CONCLUSION: This provides a reference for choosing the best timing of convalescent plasma treatment and highlights the effectiveness of the clinical strategy of plasma treatment in the recovery period of patients with COVID-19 pneumonia.
ABSTRACT
We propose a new modeling framework for evaluating the risk of disease transmission during a pandemic in small-scale settings driven by stochasticity in the arrival and service processes, i.e., congestion-prone confined-space service facilities, such as grocery stores. We propose a novel metric ($R_0^{\mathsf{sys}}$) inspired by $R_0$, the "basic reproduction number" concept from epidemiology, which measures the transmissibility of infectious diseases. We derive the $R_0^{\mathsf{sys}}$ metric for various queueing models of service facilities by leveraging a novel queueing-theoretic notion: sojourn time overlaps. We showcase how our metric can be used to explore the efficacy of a variety of interventions aimed at curbing the spread of disease inside service facilities. Specifically, we focus on some prevalent interventions employed during the COVID-19 pandemic: limiting the occupancy of service facilities, protecting high-risk customers (via prioritization or designated time windows), and increasing the service speed (or limiting patronage duration). We discuss a variety of directions for adapting our transmission model to incorporate some more nuanced features of disease transmission, including heterogeneity in the population immunity level, varying levels of mask usage, and spatial considerations in disease transmission.
Subject(s)
COVID-19 , Communicable DiseasesABSTRACT
The 2019 novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally, while the routes of transmission of this virus are still controversial. We enrolled 33 patients, without any ocular manifestation, with their ocular surface swabs collected for virus detection. RNA was detected strong positive in samples of both eyes from two patients. Therefore, SARS-CoV-2 may exist in the normal ocular surface of COVID-19 patients, suggesting that this virus might be spread through conjunctival contact.