scholarly journals 43. SARS-CoV-2 Cycle threshold (Ct) values predict future COVID-19 cases

2021 ◽  
Vol 8 (Supplement_1) ◽  
pp. S31-S32
Author(s):  
Matthew Phillips ◽  
David Quintero ◽  
Susan Butler-Wu

Abstract Background The threat of surging COVID-19 cases prompted many hospitals in the United States to preemptively suspend elective procedures throughout the pandemic. Utilizing samples from a large hospital in Los Angeles, we sought to determine if temporal trends in SARS-CoV-2 Cycle threshold (Ct) values (proxy for viral RNA loads) were predictive for the number of future COVID-19 cases. Methods Nasopharyngeal specimens on symptomatic patients and asymptomatic admissions were tested using the Xpert Xpress SARS-CoV-2 and SARS-CoV-2/Flu/RSV assays (Cepheid). Ct values for all SARS-CoV-2 detections between October 2020 to March 2021 were compiled for analysis. Results A total of 2,114 SARS-CoV-2-positive samples were included. The number of tests performed per week increased dramatically in December peaking the first week of January before returning to pre-surge numbers by Mid-February. Ct values fell during this same period with values in December and January (25.6±7.8 and 27±7.9, respectively) significantly lower than those of the other months (30±9.3 to 37.7±6.3). Average weekly Ct values for all patients were significantly, negatively correlated with the number of tests run the following week (R= -0.71, P< 0.001) and two weeks later (R= -0.75, P< 0.0001). Ct values for patients who were asymptomatic at the time of testing most strongly correlated with total number of tests performed one month later (R= -0.86, P< 0.0001). Average weekly Ct values and number of test run As cases (light grey) increased during December and January, there was a significant decrease in Ct values (dark grey) during that same time period. Average Ct values are a leading indicator of cases Average weekly Ct values for all patients (light grey) were significantly, negatively correlated with the number of tests run the following week (R= -0.71, P<0.001) and two weeks later (R= -0.75, P<0.0001). Ct values for patients who were asymptomatic at the time of testing (dark grey) most strongly correlated with total number of tests performed one month later (R= -0.86, P<0.0001). Conclusion Lower Ct values, representing higher levels of viral RNA, have been associated with risk of intubation and infectivity. During the winter surge, we observed significantly lower Ct values suggesting that the increased transmission and morbidity of COVID-19 was temporarily associated with higher viral loads. Interestingly, Ct values for asymptomatic patients were most strongly associated with number of cases observed 1 months in the future, suggesting that asymptomatic viral load may be a leading indicator for forthcoming outbreaks. Given this association, Ct values may be a useful tool for predicting regional outbreaks of COVID-19 and more judicious cessation of elective procedures. Disclosures All Authors: No reported disclosures

Author(s):  
Teppei Sakano ◽  
Mitsuyoshi Urashima ◽  
Hiroyuki Takao ◽  
Kohei Takeshita ◽  
Hiroe Kobashi ◽  
...  

In the coronavirus disease 2019 (COVID-19) pandemic, more than half of the cases of transmission may occur via asymptomatic individuals, which makes it difficult to contain. However, whether viral load in the throat during admission is different between asymptomatic and symptomatic patients is not well known. By conducting a prospective cohort study of patients with asymptomatic or mild COVID-19, cycle threshold (Ct) values of the polymerase chain reaction test for COVID-19 were examined every other day during admission. The Ct values during admission increased more steadily in symptomatic patients and febrile patients than in asymptomatic patients, with significance (p = 0.01 and p = 0.004, respectively), although the Ct values as a whole were not significantly different between the two groups. Moreover, the Ct values as a whole were higher in patients with dysosmia/dysgeusia than in those without it (p = 0.02), whereas they were lower in patients with a headache than those without (p = 0.01). Patients who were IgG-positive at discharge maintained higher Ct values, e.g., more than 35, during admission than those with IgG-negative (p = 0.03). Assuming that viral load and Ct values are negatively associated, the viral loads as a whole and their changes by time may be different by symptoms and immune reaction, i.e., IgG-positive at discharge.


Author(s):  
Phillip P Salvatore ◽  
Patrick Dawson ◽  
Ashutosh Wadhwa ◽  
Elizabeth M Rabold ◽  
Sean Buono ◽  
...  

Abstract Background Detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has principally been performed through the use of real-time reverse-transcription polymerase chain reaction testing. Results of such tests can be reported as cycle threshold (Ct) values, which may provide semi-quantitative or indirect measurements of viral load. Previous reports have examined temporal trends in Ct values over the course of a SARS-CoV-2 infection. Methods Using testing data collected during a prospective household transmission investigation of outpatient and mild coronavirus disease 2019 cases, we examined the relationships between Ct values of the viral RNA N1 target and demographic, clinical, and epidemiological characteristics collected through participant interviews and daily symptom diaries. Results We found that Ct values are lowest (corresponding to a higher viral RNA concentration) soon after symptom onset and are significantly correlated with the time elapsed since onset (P < .001); within 7 days after symptom onset, the median Ct value was 26.5, compared with a median Ct value of 35.0 occurring 21 days after onset. Ct values were significantly lower among participants under 18 years of age (P = .01) and those reporting upper respiratory symptoms at the time of sample collection (P = .001), and were higher among participants reporting no symptoms (P = .05). Conclusions These results emphasize the importance of early testing for SARS-CoV-2 among individuals with symptoms of respiratory illness, and allow cases to be identified and isolated when their viral shedding may be highest.


1970 ◽  
Vol 09 (02) ◽  
pp. 75-80
Author(s):  
B. G. Lamson ◽  
W. S. Russell ◽  
J. Fullmore ◽  
W. E. Nix

Total information and communication systems within hospitals have been designed, but successful complete implementation, to date, has not been achieved. Limited applications with both patient medical data, notably in the clinical laboratories, and in the hospital accounting offices have been numerous. Although total programs are not yet a reality, it is apparent that the computer will serve ultimately many communication requirements, both medical and financial, within the hospital.Sound hospital management requires that costs of all component operations be known in order that value judgments concerning worth and efficiency may be made. Accrual accounting systems which match revenue and expense over the same time period are a prerequisite. Cash and modified cash hospital accounting cannot provide current reliable data for sound decision making.Costs of hospital operations cannot be evaluated unless related to the characteristics of the patient service load. Average per diem costs mean little except when large similar populations of patients are being compared. A modern hospital accrual accounting system should be able to provide information concerning the costs of caring for specific diseases in patients with known age and sex and disease severity characteristics. Without information of this type, it will not be possible to objectively evaluate alternative systems of financing and organizing patient care.Medical record management offers the promise of prospective use of patient disease information in the planning and scheduling of facilities. The prose content of medical record summaries, such as diagnostic statements in tissue pathology, radiology, and admission and discharge diagnoses, may be susceptible to non-coded, full prose input into computer controlled diagnostic files. Thesauri in the several medical specialties will be necessary for this achievement.There is little immediate prospect for complete hospital communication systems that can be made available as a package to any hospital without substantial local alteration. Pilot projects in teaching centers should be viewed for the time being as opportunities to define objectives, evaluate feasibility, and determine degree of risk and expense.A brief survey of applications in the United States which have been successfully implemented or which appear suitable for successful implementation is recorded.Eleven general principles which have been associated with successful implementation of computer applications within the UCLA Hospital are enumerated.


2003 ◽  
Vol 1 (2) ◽  
pp. 44-51
Author(s):  
Kristine Brown ◽  
James Sturges

With the continued influx of Mexican immigrants to the United States, especially to Southern California, health concerns and needs have increased among this population over the last several years. California State Polytechnic University, Pomona (Cal Poly Pomona) obtained a federal grant that provided resources to establish the Community Outreach Partnership Center (COPC). COPC consists of comprehensive efforts to improve the overall well-being of the Angela Chanslor area within the City of Pomona in East Los Angeles. Focus areas of the project include 1) Education and Integrated Services, 2) Community Planning and Capacity Building for Neighborhood Revitalization and Safety, and 3) Job Development and Training. The focus of this paper is health promotion activities within Education and Integrated Services. The primary objective of this portion of the program was to provide residents with physical examinations and health screenings, health education, and medical and social service referrals. Topics discussed are the target community, general overview of COPC, Family Services Information and Referral Program (i.e. health promotion program within Education and Integrated Services), program impact and results, and suggestions for continued implementation and future efforts. / Con la influencia continua de inmigrantes Mexicanos a los Estados Unidos, especialmente al sur de California, ciertas necesidades con respecto a la salud han incrementado en esta poblacion en los ultimos anos. California State Polytechnic University, Pomona (Cal Poly Pomona). Obtuvo ayuda Federal para establecer El Community Outreach Partnership Center (COPC). El centro COPC consiste de esfuerzos conprensivos para mejorar el bienestar del area Angela Chanslor que esta ubicado en la Ciudad de Pomona en la parte Este de Los Angeles. Las partes enfocadas del proyecto incluyen, 1) Educacion y servicios Integrados, 2) Plan para la Comunidad y un Edificio de Capacitacion para la comunidad que dara revitalizacion y seguridad, 3) Y habrira trabajos y entrenamientos. El enfoque de este proyecto es de actividades en Promocion de Salud aliadas con educacion y Servicios Integrados. El objetivo principal de esta porcion del programa era de proveer a los residentes con examinaciones fisicas, educacion para la salud, y eran referidas a servicios medicos y sociales. Los topicos que son tratados son: La comunidad que sera ayudada, El enfoque general de COPC, informacion del programa para referir a servicios familiares, el impacto del programa y resultados, y sugerencias para implementar futuros esfuerzos.


2020 ◽  
Vol 20 (2) ◽  
pp. 45-54
Author(s):  
Samuel H. Yamashita

In the 1970s, Japanese cooks began to appear in the kitchens of nouvelle cuisine chefs in France for further training, with scores more arriving in the next decades. Paul Bocuse, Alain Chapel, Joël Robuchon, and other leading French chefs started visiting Japan to teach, cook, and sample Japanese cuisine, and ten of them eventually opened restaurants there. In the 1980s and 1990s, these chefs' frequent visits to Japan and the steady flow of Japanese stagiaires to French restaurants in Europe and the United States encouraged a series of changes that I am calling the “Japanese turn,” which found chefs at fine-dining establishments in Los Angeles, New York City, and later the San Francisco Bay Area using an ever-widening array of Japanese ingredients, employing Japanese culinary techniques, and adding Japanese dishes to their menus. By the second decade of the twenty-first century, the wide acceptance of not only Japanese ingredients and techniques but also concepts like umami (savory tastiness) and shun (seasonality) suggest that Japanese cuisine is now well known to many American chefs.


2020 ◽  
Vol 13 (1) ◽  
pp. 5
Author(s):  
William Straka ◽  
Shobha Kondragunta ◽  
Zigang Wei ◽  
Hai Zhang ◽  
Steven D. Miller ◽  
...  

The COVID-19 pandemic has infected almost 73 million people and is responsible for over 1.63 million fatalities worldwide since early December 2019, when it was first reported in Wuhan, China. In the early stages of the pandemic, social distancing measures, such as lockdown restrictions, were applied in a non-uniform way across the world to reduce the spread of the virus. While such restrictions contributed to flattening the curve in places like Italy, Germany, and South Korea, it plunged the economy in the United States to a level of recession not seen since WWII, while also improving air quality due to the reduced mobility. Using daily Earth observation data (Day/Night Band (DNB) from the National Oceanic and Atmospheric Administration Suomi-NPP and NO2 measurements from the TROPOspheric Monitoring Instrument TROPOMI) along with monthly averaged cell phone derived mobility data, we examined the economic and environmental impacts of lockdowns in Los Angeles, California; Chicago, Illinois; Washington DC from February to April 2020—encompassing the most profound shutdown measures taken in the U.S. The preliminary analysis revealed that the reduction in mobility involved two major observable impacts: (i) improved air quality (a reduction in NO2 and PM2.5 concentration), but (ii) reduced economic activity (a decrease in energy consumption as measured by the radiance from the DNB data) that impacted on gross domestic product, poverty levels, and the unemployment rate. With the continuing rise of COVID-19 cases and declining economic conditions, such knowledge can be combined with unemployment and demographic data to develop policies and strategies for the safe reopening of the economy while preserving our environment and protecting vulnerable populations susceptible to COVID-19 infection.


2021 ◽  
Vol 9 (4) ◽  
pp. 798
Author(s):  
Giorgia Caruana ◽  
Antony Croxatto ◽  
Eleftheria Kampouri ◽  
Antonios Kritikos ◽  
Onya Opota ◽  
...  

Following the Swiss Federal Office of Public Health (FOPH) authorization of the rapid antigen test (RAT), we implemented the use of the RAT in the emergency ward of our university hospital for patients’ cohorting. RAT triaging in association with RT-PCR allowed us to promptly isolate positive patients and save resources. Among 532 patients, overall sensitivities were 48.3% for Exdia and 41.2% for Standard Q®, PanbioTM and BD Veritor™. All RATs exhibited specificity above 99%. Sensitivity increased to 74.6%, 66.2%, 66.2% and 64.8% for Exdia, Standard Q®, PanbioTM and BD Veritor™, respectively, for viral loads above 105 copies/mL, to 100%, 97.8%, 96.6% and 95.6% for viral loads above 106 copies/mL and 100% for viral loads above 107 copies/mL. Sensitivity was significantly higher for patients with symptoms onset within four days (74.3%, 69.2%, 69.2% and 64%, respectively) versus patients with the evolution of symptoms longer than four days (36.8%, 21.1%, 21.1% and 23.7%, respectively). Among COVID-19 asymptomatic patients, sensitivity was 33%. All Immunoglobulin-A-positive patients resulted negative for RAT. The RAT might represent a useful resource in selected clinical settings as a complementary tool in RT-PCR for rapid patient triaging, but the lower sensitivity, especially in late presenters and COVID-19 asymptomatic subjects, must be taken into account.


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